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01

DESKTOP-PVTUser Guide© 2001 Landmark Graphics Corporation

Part No. 159677 R2003 September 20

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erprise,Works,FILE,

aView,

Form

Trademarks

Landmark, Landmark logo, 3DVIEW, ARIES, Automate, BLITZ, BLITZPAK, CasingSeat, COMPASS, Contouring AssistanDecision Suite, Decisionarium, DecisionDesktop, DepthTeam, DepthTeam Explorer, DepthTeam Express, DepthTeam ExDepthTeam Interpreter, DESKTOP-PVT, DESKTOP-VIP, DEX, DFW, DIMS, Discovery, Drillability Suite, DrillModel, DSS,EarthCube, EdgeCa$h, FastTrack, FZAP!, GeoDataLoad, GeoGraphix, GeoLink, GES, GESXplorer, GRIDGENR, I2 EntiDims, LeaseMap, LogEdit, LogPrep, MathPack, OpenBooks, OpenExplorer, OpenJournal, OpenSGM, OpenVision, OpenPAL, Parallel-VIP, PetroWorks, PlotView, Point Gridding Plus, Pointing Dispatcher, PostStack, PostStack ESP, PRIZM, PROProMAX, ProMAX 2D, ProMAX 3D, ProMAX 3DPSDM, ProMAX MVA, ProMAX VSP, RAVE, Reservoir Framework Builder,RESev, ResMap, RMS, SafeStart, SeisCube, SeisMap, SeisModel, SeisVision, SeisWell, SeisWorks, SeisXchange, SigmStrataMap, Stratamodel, StratAmp, StrataSim, StratWorks, StressCheck, SynTool, SystemStart, SystemStart for Clients,SystemStart for Servers, SystemStart for Storage, T2B, TDQ, TERAS, TOW/cs, TOW/cs The Oilfield Workstation, Trend Gridding, VIP, VIP-COMP, VIP-CORE, VIP-DUAL, VIP-ENCORE, VIP-EXECUTIVE, VIP-Local Grid Refinement, VIP-POLYMER, VIP-THERM, Wellbase, Wellbore Planner, WELLCAT, WELLPLAN, WellXchange, ZAP! and Z-MAP Plus aretrademarks or registered trademarks of Landmark Graphics Corporation.

All other trademarks are the property of their respective owners.

❖

Table of Contents

PrefaceAbout This Manual

Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv

Audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv

Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv

Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviMouse Buttons (Interactive Graphics)

xviMouse Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviiKey Combinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviiKeyboard Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviii

Cursor Movement Control Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . xviiiF2 Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviiiF5 Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviii

For More Information... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviii

Chapter 1Introduction

1.1 Program Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

1.2 Hardware/Software Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Chapter 2Getting Started

2.1 Starting DESKTOP-PVT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

2.2 Main Screen Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-62.2.1 Menu Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6

2.3 Data Entry Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8

2.4 Pop-Up Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-82.4.1 File Box Popup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-82.4.2 Text Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-92.4.3 Single Item Selection Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10

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2.4.4 Multiple Item Selection Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-112.4.5 Option Flag/Confirm Dialog . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-122.4.6 List Entry Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-132.4.7 Rectangular List Entry Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-142.4.8 Triangular Table Entry Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15

2.5 Invoke Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16

2.6 Get Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16

2.7 File Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-162.7.1 Batch Data File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-162.7.2 Database File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-172.7.3 EOS Data File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-172.7.4 Report Text File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-182.7.5 PostScript Output File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18

Chapter 3Input Data File

3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-19

3.2 Last Run - Recall Data From Backup File . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-19

3.3 Open - Load Batch File Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-20

3.4 New - Initialize Data To Default Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-20

3.5 Save - Save Data Into Batch Data File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-20

3.6 Load Database - Load Data From Database File . . . . . . . . . . . . . . . . . . . . . . 3-20

3.7 Save Database - Save Data To Database File . . . . . . . . . . . . . . . . . . . . . . . . . 3-20

3.8 Exit - Terminate DESKTOP-PVT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-21

Chapter 4Setup Simulation Environment

4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-23

4.2 System Info - Add Descriptive Text For Data Set . . . . . . . . . . . . . . . . . . . . . 4-24

4.3 EOS - Equation-of-State Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-24

4.4 Binary Coeff - Binary Interaction Coefficients Options . . . . . . . . . . . . . . . . 4-25

4.5 Test Type - Laboratory Tests Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-25

4.6 Regression - Automatic Parameter Adjustment Option . . . . . . . . . . . . . . . 4-27

4.7 Pseudoization - Pseudoization Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-27

4.8 Thermal - Thermal Application Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-28

4.9 Water-In-Oil - Water in Oil Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-29

4.10 Heavy - Heavy Fraction Characterization Option . . . . . . . . . . . . . . . . . . . 4-29

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4.11 Run-Time Compos - Run-Time Composition Specification Option . . . . . 4-29

Chapter 5Equation-of-State Properties

5.1 Component . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-315.1.1 System - Select Component From System Default Table . . . . . . . 5-315.1.2 User - Make User-Defined Component . . . . . . . . . . . . . . . . . . . . . . 5-325.1.3 Volatile - Define Volatile Component . . . . . . . . . . . . . . . . . . . . . . . 5-335.1.4 Composition - Global Reference Composition . . . . . . . . . . . . . . . . 5-335.1.5 Load EOS - Load Component From File . . . . . . . . . . . . . . . . . . . . . 5-345.1.6 Append EOS - Append Component From File . . . . . . . . . . . . . . . 5-34

5.2 Fluid Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-355.2.1 Property - EOS Property . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-36

Temperature & Pressure Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-36Property Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-36Volume Shift Parameters (D & E) . . . . . . . . . . . . . . . . . . . . . . . . . . 5-38

5.2.2 Binary Coeff - Binary Interaction Coefficients . . . . . . . . . . . . . . . . 5-385.2.3 Gas Enthalpy - Ideal Gas State Enthalpy Coefficients . . . . . . . . . . 5-395.2.4 LBC Visc - Lohrenz-Bray-Clark Viscosity Correlation . . . . . . . . . 5-415.2.5 Pedersen Visc - Pedersen Viscosity Correlation . . . . . . . . . . . . . . . 5-425.2.6 K-Value Correl - Component K-Value Correlation . . . . . . . . . . . . 5-445.2.7 CO2TAB Correl-Correlation of CO2 Saturated Water Properties 5-44

Chapter 6Heavy/Pseudo/Regres

6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-49

6.2 Heavy - Heavy Fraction Characterization . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-506.2.1 Parameter - Input For Heavy Fraction Characterization . . . . . . . 6-506.2.2 Calculate - Activate Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-566.2.3 Graphics - Graphic Results of Extended Analysis . . . . . . . . . . . . . 6-576.2.4 Review - Tabular Results of Pseudo-Components . . . . . . . . . . . . . 6-576.2.5 Save EOS - Save EOS Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-576.2.6 Append EOS - Add Heavy Fraction Components to System . . . . 6-576.2.7 Replace EOS - Load Heavy Fraction Components to System . . . 6-57

6.3 Pseudo - Pseudoization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-586.3.1 Pseudo Name - Assign Pseudo-Components . . . . . . . . . . . . . . . . . 6-586.3.2 Parameter - Input for Pseudoization . . . . . . . . . . . . . . . . . . . . . . . . 6-596.3.3 Calculate - Activate Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-606.3.4 Review - Tabular Results of Pseudoization . . . . . . . . . . . . . . . . . . 6-606.3.5 Save EOS - Save EOS Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-606.3.6 Replace EOS - Load Pseudo Components To System . . . . . . . . . . 6-616.3.7 Append EOS - Add Pseudo Components To System . . . . . . . . . . 6-61

6.4 Regres - Automatic Parameter Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . 6-62

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6.4.1 Variable - Regression Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-626.4.2 Limits - Upper and Lower Bounds . . . . . . . . . . . . . . . . . . . . . . . . . . 6-696.4.3 Control - Calculation and Output Control . . . . . . . . . . . . . . . . . . . 6-70

Chapter 7Input Data for Laboratory Procedures

7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-73

7.2 Common Input Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-747.2.1 Composition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-747.2.2 Laboratory Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-757.2.3 Temperature Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-757.2.4 Pressure Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-767.2.5 Density Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-767.2.6 Gas-Oil Ratio Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-767.2.7 Enthalpy Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-777.2.8 Saturation Pressure Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-777.2.9 Weight Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-77

7.3 Input Data for Laboratory Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-787.3.1 Z-Factor: Gas Compressibility Factor . . . . . . . . . . . . . . . . . . . . . . . 7-797.3.2 Density: Liquid Density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-817.3.3 Vapor Pressure: Pure Component Vapor Pressure . . . . . . . . . . . . 7-837.3.4 Sat Pressure: Mixture Dew/Bubblepoint Pressure . . . . . . . . . . . . 7-857.3.5 Viscosity: Liquid/Vapor Viscosity . . . . . . . . . . . . . . . . . . . . . . . . . . 7-877.3.6 Cnst Composition: Constant Composition Expansion . . . . . . . . . 7-887.3.7 Cnst Volume: Constant Volume Depletion . . . . . . . . . . . . . . . . . . . 7-927.3.8 Swelling: Swelling Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-977.3.9 Differential: Differential Expansion . . . . . . . . . . . . . . . . . . . . . . . . . 7-997.3.10 Multi-Contact: Multiple Contact Vaporization . . . . . . . . . . . . . 7-1027.3.11 Phas Envlop/Psat: Dew/Bubblepoint Phase Envelope . . . . . . 7-1047.3.12 Gas Enthalpy: Gas Enthalpy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1077.3.13 Liquid Enthalpy: Liquid Enthalpy . . . . . . . . . . . . . . . . . . . . . . . . 7-1097.3.14 Water Property: Liquid Water Property . . . . . . . . . . . . . . . . . . . 7-1117.3.15 Sat Pressure/H2O: Bubblepoint Pressure of Mixture

With Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1127.3.16 Distillation: Distillation Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-114

Distillation Curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-116Molecular Weight Measurements . . . . . . . . . . . . . . . . . . . . . . . . . 7-117Residue API Gravity Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-118Distillate Property Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-119Blend API Gravity Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-122Viscosity Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-123

7.3.17 Steam Distillatn: Steam Distillation Test . . . . . . . . . . . . . . . . . . . 7-1277.3.18 Separator/No Reg: Multistage Separators Without Regression 7-1307.3.19 Separator/Reg: Laboratory Separator Test With Regression . . 7-132

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7.3.20 Phas Envlop/Full: Complete Phase Envelope . . . . . . . . . . . . . . 7-1367.3.21 ZGRAD: Composition Variations With Depth . . . . . . . . . . . . . . 7-1377.3.22 CO2TAB: Properties of Carbon Dioxide Saturated Water . . . . 7-1417.3.23 Steam Vaporizatn: Multiple Contact Steam Vaporization . . . . 7-1457.3.24 Two Phase Isothermal Flash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-152

Chapter 8Calculation of Laboratory Procedures

8.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-155

8.2 Activate Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-156

8.3 Selection of Calculation Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-156

8.4 Control Parameters for Saturation Pressure Calculation . . . . . . . . . . . . . . 8-157

8.5 Control Parameters for Flash Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . 8-158

8.6 Control Parameters for Expansion Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-159

8.7 Debug Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-160

Chapter 9Report - Calculation Results

9.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-161

9.2 Graphics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1629.2.1 Selecting Test Procedure for Plot . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1629.2.2 Interactive Graphic Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-165

ZOOM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-166VALUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-168L_TYPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-168COLOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-168TEXT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-169PRINTER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-171REDRAW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-171HIGHER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-171

9.3 GraTitle - Running Title for Plot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-172

9.4 SavGraph - Save Graphic Report to File . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-172

9.5 GetGraph - Get Graphic Report from File . . . . . . . . . . . . . . . . . . . . . . . . . . 9-173

9.6 Table - Review Tabular Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-173

9.7 PrtTable - Print Tabular Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-173

9.8 SavTable - Save Tabular Report to File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-173

9.9 GetTable - Get Tabular Report from File . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-174

9.10 SaveEOS - Save PVT (EOS) Properties to File . . . . . . . . . . . . . . . . . . . . . . 9-174

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9.11 SaveKval - Save K-value Tables to File . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-174

9.12 SaveVisc - Save Component Viscosity Tables to File . . . . . . . . . . . . . . . . 9-175

9.13 SaveZgrd - Save Composition-vs-Depth Table to File . . . . . . . . . . . . . . . 9-175

9.14 SaveCO2T - Save CO2-Saturated-Water-Property Table to File . . . . . . . 9-175

9.15 SaveBOE - Save Black Oil Table to File. . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-175

Chapter 10Tutorial

10.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-177

10.2 Heavy Ends Characterization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-177

10.3 Default Fluid Predictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-179

10.4 Regression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-183

10.5 Component Pseudoization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-185

10.6 Regression After Pseudoization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-188

10.7 Regression on Viscosity Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-190

Appendix AReferencesSubject Index

viii Landmark - R2003.0

❖

List of Figures

PrefaceAbout This Manual

Chapter 1Introduction

Chapter 2Getting Started

Figure 2-1: An Example of Rectangular Push Buttons forMultiple Item Selection Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

Figure 2-2: An Example of Square Toggle Buttons for MultipleItem Selection Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

Chapter 3Input Data File

Chapter 4Setup Simulation Environment

Figure 4-1: EOS Item Selection Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-24

Figure 4-2: Test Type Selection Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-25

Figure 4-3: Composition Sor List Entry Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-28

Figure 4-4: Run Sequence Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-30

Chapter 5Equation-of-State Properties

Figure 5-1: System-Defined Component Panel . . . . . . . . . . . . . . . . . . . . . . . . . . 5-32

Figure 5-2: User Defined Fluid Component Table . . . . . . . . . . . . . . . . . . . . . . . 5-33

Figure 5-3: Volatile Component Selection Panel . . . . . . . . . . . . . . . . . . . . . . . . . 5-33

Figure 5-4: Global Reference Composition Panel . . . . . . . . . . . . . . . . . . . . . . . . 5-34

Figure 5-5: Equation-of-State Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-36

R2003.0 - Landmark ix


Figure 5-6: EOS Property Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-37

Figure 5-7: Binary Exponent Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-39

Figure 5-8: Gas Enthalpy Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-40

Figure 5-9: Coefficients of Lohrenz-Bray-Clark Viscosity Correlation . . . . . . 5-41

Figure 5-10: k-coefficients of Pedersen Viscosity Correlation . . . . . . . . . . . . . . 5-43

Figure 5-11: Tc-Binary Interaction Coefficient of PedersenViscosity Correlation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-43

Figure 5-12: Component Coefficients of K-Value Correlation . . . . . . . . . . . . . 5-44

Figure 5-13: Correlation Coefficients of Carbon Dioxide SaturatedWater Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-45

Figure 5-14: Correlation Coefficients of Solubility of Carbon Dioxide inPure Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-45

Figure 5-15: Adjusting the Salinity Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-47

Figure 5-16: Calculating Carbon Dioxide Saturation Water Density . . . . . . . . 5-48

Chapter 6Heavy/Pseudo/Regres

Figure 6-1: Parameter Options Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-51

Figure 6-2: Pseudoization Parameter Options Form . . . . . . . . . . . . . . . . . . . . . 6-59

Figure 6-3: Regression Variable Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-63

Figure 6-4: EOS Regression Variable Definition Table . . . . . . . . . . . . . . . . . . . . 6-63

Figure 6-5: Binary Coeff Regression Variable Definition Table . . . . . . . . . . . . 6-64

Figure 6-6: Composition Regression Variable Definition Table . . . . . . . . . . . . 6-64

Figure 6-7: k-Coefficient of Lohrenz-Bray-Clark Viscosity Correlation . . . . . 6-65

Figure 6-8: k-Coefficient of Pedersen Viscosity Correlation . . . . . . . . . . . . . . . 6-65

Figure 6-9: Tc-Binary Interaction Coefficient of PedersonViscosity Correlation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-66

Figure 6-10: Component Coefficients of K-Value Correlation . . . . . . . . . . . . . 6-66

Figure 6-11: Correlation Coefficients of Carbon Dioxide SaturatedWater Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-67

Figure 6-12: Correlation Coefficients of Solubility of Carbon Dioxide inPure Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-67

Figure 6-13: Assigning Regression Variables to s0 and s1 Coefficients . . . . . . 6-68

Figure 6-14: Assigning Regression Variable to Coefficient d1 . . . . . . . . . . . . . . 6-68

Figure 6-15: Regression Limits Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-69

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Figure 6-16: Regression Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-70

Chapter 7Input Data for Laboratory Procedures

Figure 7-1: Gas Z-Factor Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-79

Figure 7-2: Data Entry Table for Gas Z-Factor . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-80

Figure 7-3: Liquid Density Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-81

Figure 7-4: Data Entry Table for Liquid Density . . . . . . . . . . . . . . . . . . . . . . . . . 7-82

Figure 7-5: Vapor Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-83

Figure 7-6: Data Entry Table for Vapor Pressure . . . . . . . . . . . . . . . . . . . . . . . . 7-84

Figure 7-7: Saturation Pressure Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-85

Figure 7-8: Data Entry Table for Saturation Pressure . . . . . . . . . . . . . . . . . . . . . 7-86

Figure 7-9: Viscosity Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-87

Figure 7-10: Data Entry Table for Viscosity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-88

Figure 7-11: Constant Composition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-89

Figure 7-12: Data Entry Table for Constant Composition Expansion . . . . . . . 7-91

Figure 7-13: Constant Volume Depletion Menu . . . . . . . . . . . . . . . . . . . . . . . . . 7-92

Figure 7-14: Data Entry Table for Constant Volume Depletion . . . . . . . . . . . . 7-94

Figure 7-15: Black Oil Table Generation Parameters . . . . . . . . . . . . . . . . . . . . . 7-95

Figure 7-16: Separator Definition for Black Oil Table Generation. . . . . . . . . . . 7-95

Figure 7-17: Saturation Pressures at which black oil data is generated. . . . . . 7-96

Figure 7-18: Pressure levels above the saturation pressureat which black oil data is generated. . . . . . . . . . . . . . . . . . . . . . . . . 7-96

Figure 7-19: Swelling Test Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-97

Figure 7-20: Data Entry Table for Swelling Test . . . . . . . . . . . . . . . . . . . . . . . . . 7-98

Figure 7-21: Differential Expansion Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-99

Figure 7-22: Data Entry Table for Differential Expansion . . . . . . . . . . . . . . . . 7-101

Figure 7-23: Multiple Contact Vaporization Menu . . . . . . . . . . . . . . . . . . . . . . 7-102

Figure 7-24: Data Entry Table for Multiple Contact Vaporization . . . . . . . . . 7-104

Figure 7-25: Phase Envelope Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-105

Figure 7-26: Gas Enthalpy Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-107

Figure 7-27: Data Entry Table for Gas Enthalpy . . . . . . . . . . . . . . . . . . . . . . . . 7-108

Figure 7-28: Liquid Enthalpy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-109

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Figure 7-29: Data Entry Table for Liquid Enthalpy . . . . . . . . . . . . . . . . . . . . . 7-110

Figure 7-30: Water Property Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-111

Figure 7-31: BubblepointPressure of Mixture with H2O Menu . . . . . . . . . . . 7-112

Figure 7-32: Data Entry Table for Bubblepoint Pressure ofMixture with H2O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-113

Figure 7-33: Distillation Test Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-114

Figure 7-34: Data Entry Table for Distillation Curve . . . . . . . . . . . . . . . . . . . . 7-116

Figure 7-35: Data Entry Table for Distillation MolecularWeight Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-117

Figure 7-36: Data Entry Table for Distillation Residue API Gravity . . . . . . . 7-118

Figure 7-37: Data Entry Table for Distillate Property Tables . . . . . . . . . . . . . . 7-119

Figure 7-38: Data Entry Table for Distillation Distillate API Gravity . . . . . . 7-119

Figure 7-39: Data Entry Table for Distillate K-Value . . . . . . . . . . . . . . . . . . . . 7-120

Figure 7-40: Weight Factor for Distillate K-Value . . . . . . . . . . . . . . . . . . . . . . . 7-121

Figure 7-41: Weight Factor for Distillate K-Value . . . . . . . . . . . . . . . . . . . . . . . 7-121

Figure 7-42: Data Entry Table for Distillation Blend API Gravity . . . . . . . . . 7-122

Figure 7-43: Viscosity Data for Distillation Test . . . . . . . . . . . . . . . . . . . . . . . . 7-123

Figure 7-44: Data Entry Table for Crude Viscosity . . . . . . . . . . . . . . . . . . . . . . 7-124

Figure 7-45: Data Entry Table for Residue Viscosity . . . . . . . . . . . . . . . . . . . . 7-124

Figure 7-46: Data Entry Table for Distillate Viscosity . . . . . . . . . . . . . . . . . . . 7-125

Figure 7-47: Data Entry Table for Blend Viscosity . . . . . . . . . . . . . . . . . . . . . . 7-126

Figure 7-48: Steam Distillation Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-127

Figure 7-49: Data Entry Table for Steam Distillation . . . . . . . . . . . . . . . . . . . . 7-129

Figure 7-50: Multi-State Separator Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-130

Figure 7-51: Data Entry Table for Multi-Stage Separator . . . . . . . . . . . . . . . . . 7-131

Figure 7-52: Laboratory Separator Test Menu . . . . . . . . . . . . . . . . . . . . . . . . . . 7-133

Figure 7-53: Data Entry Table for Laboratory Separator Test . . . . . . . . . . . . . 7-135

Figure 7-54: Complete Phase Envelope Menu . . . . . . . . . . . . . . . . . . . . . . . . . . 7-136

Figure 7-55: Composition Variations with Depth Menu . . . . . . . . . . . . . . . . . 7-138

Figure 7-56: Optional Input for Composition Variables with Depth . . . . . . . 7-140

Figure 7-57: Calculating Properties of Carbon Dioxide Saturated Water . . . 7-142

Figure 7-58: Laboratory Measured Data for SATWAT Option . . . . . . . . . . . 7-143

Figure 7-59: Measured Data of Carbon Dioxide Saturated Water . . . . . . . . . 7-144

xii Landmark - R2003.0


Figure 7-60: Simulating the MCSVAP Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-146

Figure 7-61: Laboratory Measured MCSVAP Data . . . . . . . . . . . . . . . . . . . . . . 7-147

Figure 7-62: Viscosity Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-149

Figure 7-63: Measured Initial Oil Viscosity . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-150

Figure 7-64: Measured PVT Cell Oil Viscosity . . . . . . . . . . . . . . . . . . . . . . . . . 7-151

Figure 7-65: Laboratory Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-152

Figure 7-66: Laboratory Measurements Vertical List . . . . . . . . . . . . . . . . . . . . 7-153

Chapter 8Calculation of Laboratory Procedures

Figure 8-1: Calculation Method Selection Panel . . . . . . . . . . . . . . . . . . . . . . . . 8-156

Figure 8-2: Control Parameters for Saturation Pressure Calculation . . . . . . . 8-157

Figure 8-3: Control Parameters for Flash Calculation . . . . . . . . . . . . . . . . . . . 8-158

Figure 8-4: Control Parameters for Expansion Test . . . . . . . . . . . . . . . . . . . . . 8-159

Figure 8-5: Debug Option Selection Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-160

Chapter 9Report - Calculation Results

Figure 9-1: Selecting Test for Plot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-162

Figure 9-2: Example Plot with Graphic Menu Bar . . . . . . . . . . . . . . . . . . . . . . 9-163

Figure 9-3: Example Plot with the Control Item Selected on the Graphic Menu Bar9-165

Figure 9-4: Example Plot with Zoom Control Option . . . . . . . . . . . . . . . . . . . 9-166

Figure 9-5: Example Plot with Text Edit Option . . . . . . . . . . . . . . . . . . . . . . . . 9-169

Chapter 10Tutorial

Appendix AReferencesSubject Index

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xiv Landmark - R2003.0

Preface

❖

About This Manual

Purpose

This manual describes the functions of DESKTOP-PVT™, a program

designed to simulate the behavior of hydrocarbon fluid mixtures.

DESKTOP-PVT’s purpose is to generate PVT properties or develop a

mathematical model which can be used in a compositional reservoir

simulator such as VIP-COMP to analyze oil and gas production

characteristics.

Audience

This manual is intended to assist new and experienced users of

DESKTOP-PVT in the generation of PVT properties where laboratory data

is limited, or the development of a mathematical model that agrees with

experimental data.

Organization

The information in this manual is arranged in a logical manner for

maximum ease-of-use. The following chapters are included:

■ Introduction. A general description of DESKTOP-PVT’s functions,

including hardware and software requirements.

■ Getting Started. An explanation of the DESKTOP-PVT interfaces

including program initialization, basic menu types and basic menu

operations.

■ Input Data File. An explanation of the procedures for creating, saving,

and retrieving data files.

■ Setup Simulation Environment. An explanation of the procedures for

defining the simulation environment, including required input and

calculation methods.

■ Equation-of-State Properties. An explanation of the procedures for

defining the components of the fluid system, and defining the

characteristics of individual components.

R2003.0 - Landmark xv


■ Heavy/Pseudo/Regress. An explanation of the procedures for

assigning equation-of-state components and their properties for a fluid

mixture, as well as the functions used to obtain or modify component

properties.

■ Input Data for Laboratory Procedures. An explanation of the

procedures for entering data from laboratory measurements.

■ Calculation of Laboratory Procedures. An explanation of the

procedures for activating laboratory test calculations, selecting phase

behavior calculation methods, and specifying control parameters.

■ Report - Calculation Results. An explanation of the procedure for

creating graphical and tabular reports.

■ Tutorial. A complete step-by-step example of a fluid characterization

using DESKTOP-PVT.

Conventions

This manual uses certain conventional methods to indicate the correct

mouse button and keyboard usage.

Mouse Buttons (Interactive Graphics)

The buttons on the mouse are named MB1, MB2, MB3, etc. as shown in the

illustrations above. Button arrangement may be reversed for left-handed

mouses (e.g., MB1 on far right). Typical uses for each button are described

below.

Mouse Button Typical Uses

MB1 Used to select menu options, push buttons in the applica-

tion interface, etc.

MB1 MB2 MB3

Three-Button Mouse(Right-Handed)

MB1 MB2 MB3 MB4

Four-Button Mouse(Right-Handed)

xvi Landmark - R2003.0


Mouse Operations

You can use the mouse by rolling it across the surface of the mouse pad or

desk (except on Sun). As you move the mouse, the pointer moves to a

corresponding location on the screen. The following terms are used to

describe various mouse operations:

Key Combinations

Some keys such as the Control key and Alt key are used in combination

with others. For example, you can press Control-D by holding down the

Control key and pressing the D key. The same applies to combinations like

Alt-F4, Meta-F4, etc. Always hold down the first key before pressing the

second.

MB2 Used to clear the menu area so it will not appear on a

screen dump. Also redisplays menu area.

MB3 Used to toggle on and off a help message for the high-

lighted item in the Graphics option. Also used to access

Option Flag windows.

MB4 Used to toggle on and off a help message for the high-

lighted item.

Mouse Operation Instructions

Click Press MB1 and release rapidly.

Double-click Press MB1 two times rapidly.

Triple-click Press MB1 three times rapidly.

Control-click Hold down Control key and click once.

Shift-click Hold down Shift key and click once.

Drag Hold down MB1 and move the mouse, then release

when pointer reaches desired location.

Select Click once or double-click at the indicated location.

Shade Drag the mouse pointer across a group of text, or dou-

ble-click to shade a word, or triple-click to shade a line

or a paragraph.

Set cursor Click in text at the location where you want to begin

typing.

Mouse Button Typical Uses

R2003.0 - Landmark xvii


Combining keys may also be used with mouse clicks. For example,

Control-click means to hold down the Control key and click MB1. Control-

Shift-click means to hold down the Control key and the Shift key before

clicking once with MB1.

Keyboard Operation

Cursor Movement Control Keys

The keys used to control cursor movement include the up, down, left, and

right arrow keys. If the cursor reaches the boundary of a multiple-page

table, a further arrow key movement in the same direction will make the

table scroll in that direction. In addition, the left and right arrow keys

allow the user to move the cursor in the data field to edit previously

entered data.

F2 Key

Depending on the occasion, the F2 function key can serve one of two

functions:

1. In composition entry tables, the F2 key will copy fluid compositions

from other sources. (see Section 7.2.1)

2. In the fluid property table, the F2 key will load default component

properties, i.e., either from system default tables or using interpolation

calculations. (see Section 5.2.1)

F5 Key

In a list entry panel, the F5 function key will either display a cascade table

for additional data entry, or a selection menu for the user to specify an

option (see Section 2.4.6). The user must first place the mouse cursor over

the box cell for the F5 function key work.

For More Information...

The following manuals provide more information related to the material

in this manual. For more information, please consult the appropriate

manual listed below.

■ DESKTOP-PVT Keyword Reference Manual.

xviii Landmark - R2003.0

Chapter

1

Introduction

1.1 Program Function

DESKTOP-PVT™ is an interactive phase behavior program designed to

simulate the behavior of hydrocarbon fluid mixtures subjected to any

variety of laboratory procedures. The fluids may be either liquid or vapor,

and may undergo phase changes during the simulated experiments.

DESKTOP-PVT is designed to be user friendly through employing an

event-driven interface with pull-down menus and pop-up windows.

DESKTOP-PVT allows the user to enter data directly on screen or import

data from an existing batch-type input file. It is easy to assign fluid

properties and experimental conditions in DESKTOP-PVT. An extensive

data bank of fluid properties and default values for laboratory procedures

is built into DESKTOP-PVT. Only minimum data entry is required to

complete a simulation. In addition, DESKTOP-PVT provides tools to

create, save, and retrieve files containing input data and results

interactively. The graphical and tabular simulation results can be viewed

interactively on screen or sent to hardcopy devices. DESKTOP-PVT also

provides a batch mode option which can be employed when interactive

simulation is not feasible.

DESKTOP-PVT can be used, in a purely predictive mode, to generate PVT

properties where laboratory data is limited, or it can be used to develop a

mathematical model that agrees with experimental data. In the latter case,

the mathematical model of the fluid system can be used in a compositional

reservoir simulator such as VIP-COMP to analyze oil and gas production

characteristics. In addition, the tabular data necessary to define fluid

behavior in VIP-ENCORE may be generated by DESKTOP-PVT.

To aid in developing a fluid model that matches experimental data, a

nonlinear regression package is provided as an integral part of DESKTOP-

PVT. This facilitates the adjustment of unknown or uncertain parameters

that affect fluid behavior.

Any or all of the various laboratory procedures can be simulated in

arbitrary sequence. Fluid samples can vary in composition from one

procedure to another, and operating temperature and pressure may

change. Multiple fluid samples can be analyzed with a single laboratory

procedure by sequentially simulating the same procedure for each

different sample.

R2003.0 - Landmark 1-1


The PVT properties of both vapors and liquids are predicted by

DESKTOP-PVT by a cubic equation of state. To completely define fluid

properties it is only necessary to specify fluid composition and various

properties of individual components. The properties of a large number of

components have been internally coded. These properties are

automatically assigned unless the user elects to override the default.

DESKTOP-PVT provides a method for calculating a heavy fraction

characterization from laboratory measured properties of the heavy

fraction. The results of the heavy fraction component properties can be

added to the fluid composition to complete the fluid description.

DESKTOP-PVT also provides a calculation to combine components

through a process called pseudoization. The original fluid system is

reduced to a pseudo system by specifying which of the original

components will be lumped into which pseudo component.

The simulation data for DESKTOP-PVT is divided into six major parts:

1. Components and compositions assignment

2. Equation-of-state properties

3. Laboratory procedures

4. Automatic parameter adjustment

5. Heavy fraction characterization

6. Pseudoization

In addition, optional input is available for selecting the calculation

methods and parameters.

In the next chapter, the commands to initialize DESKTOP-PVT operation,

the basic menu types, and basic menu operations are discussed. The

detailed functions of each menu item are described in Chapters 3 to 9.

Finally, the major DESKTOP-PVT operation features using an example

simulation of a hydrocarbon reservoir fluid are presented in Chapter 10.

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1.2 Hardware/Software Requirements

DESKTOP-PVT runs on many UNIX platforms using the X-Window

System. It requires version X11R5 of the X-Window System, a X-server

(workstation display or X-terminal) for the display of the menus and

graphics and Motif 1.2. DESKTOP-PVT utilizes 16 colors and to avoid

color map problems with the window manager, the X-server should be

capable of displaying 256 simultaneous colors.

DESKTOP-PVT also now runs on Intel-based PC’s running Microsoft

Windows 2000. It must be used in conjunction with a third-party X-server

program.

Hardcopy can be generated on PostScript printers.

The following is a list of the currently supported platforms:

■ UNIX Workstations

❑ IBM RS/6000

❑ Silicon Graphics Iris Family

❑ Sun SparcStation (Solaris)

■ Microsoft Windows 2000


Chapter

2

Getting Started

2.1 Starting DESKTOP-PVT

The DESKTOP-PVT can be initialized in different ways by utilizing

various command line options.

1. At the command line prompt, type dtpvt and press the Enter key.

The program will display the main window known as the Display

Window, which contains the DESKTOP-PVT header. The user must

enter all input data through the menu process or import data from an

existing data file. Refer to Chapter 3 for details regarding the

procedure for importing an existing file through the File menu.

2. At the command line prompt, type dtpvt {file} and press the Enter key.

Here {file} is the name of a batch-type data file. Refer to Section 2.7 for

a detailed description of a batch-type data file. The data contained in

the file will be loaded into memory upon initialization and will be

ready for editing and calculation.

3. At the command line prompt, type dtpvt -b {file} and press the Enter

key.

Again, {file} is the name of a batch-type data file. The command line

option -b will direct the program to execute in the batch mode and no

further user interaction will be necessary. With this option, the user

loses the ability to review the results in the interactive graphic mode

and only the tabular report given as dtpvt.out will be generated.


Getting Started DESKTOP-PVT USER’S GUIDE

2.2 Main Screen Layout

When DESKTOP-PVT is started, a Display Window appears, as shown

below. The Display Window provides an area for viewing the graphic

reports, plus various pull-down menus (known as the Menu Bar) for

selecting program options.

2.2.1 Menu Bar

The Menu Bar contains a series of pull-down menus that lets the user

select any of the available program options. The following menus are

available:

Table 2-1: DESKTOP-PVT Display Window Menus

Menu Name DescriptionSee

Chapter

File Open files; load last run; save data; loads

and saves database files

3

Config Setup the simulation environment 4

Component Define the components of the fluid system. 5

Heavy Calculating heavy fraction characteriza-

tion from laboratory measured properties.

6

Menu Bar

Display Window

GraphicDisplayArea


DESKTOP-PVT USER’S GUIDE Getting Started

To select any menu option, just click on the desired menu and select the

desired option (or drag the mouse pointer to it). For example, to open a

file, with MB1 click the word File on the Menu Bar, then click the word

Open on the pull-down menu. A pop-up window appears which displays

a list of file names to be opened.

Some menu items may not be available for users to access if the items in

the Config menu are not adequately defined. For example, the Heavy

menu will not be accessible if the Heavy option in the Config menu is not

turned on. This is because the Menu Bar has been set up so that irrelevant

menu items will not be displayed and cannot be accessed. There are four

optional menus: Heavy, Pseudo, Regres, and Tests. The appearance of the

first three menus are controlled by the corresponding items in the Config

menu using a yes/no flag, i.e., the flag will be used to turn on/off the

appropriate menu items. The Tests menu has a dynamic arrangement,

such that only the tests which have been selected in the Test Type selection

window in the Config menu will be highlighted. Refer to Chapter 4 for a

detailed description of the Config menu.

Although there is no strict rule for the order of data entry, a typical

simulation will follow a "left to right" sequence in DESKTOP-PVT. For

example, a user may first retrieve an input data file using Open in the File

menu. The user can then reconfigure the simulation environment by

invoking the items in the Config menu. Components may be added/

deleted through the Component menu, or component properties may be

modified through the Fluid menu. The conditions of laboratory

procedures may be changed through the Tests menu. Once all changes are

completed, the user selects Go from the Run menu to start the calculation

Pseudo Used to combine and reduce original fluid

components.

6

Regres Enter parameters for non-linear regression

calculation.

6

Fluid Define the PVT characteristics of individual

components.

5

Tests Enter data from laboratory measurements. 7

Run Activating laboratory test calculations;

selecting phase behavior calculation meth-

ods; and specifying control parameters.

8

Report Graphic and tabular reports for calculated

results.

9

Table 2-1: DESKTOP-PVT Display Window Menus

Menu Name DescriptionSee

Chapter



process. Finally, the user may review the results by selecting Graphics

from the Report menu.

2.3 Data Entry Methods

Both keyboard and mouse operations are employed by DESKTOP-PVT.

Several function keys, which are frequently used during data entry, are

described in the Preface. Descriptions of mouse operations for the graphic

session are discussed in Chapter 10.

2.4 Pop-Up Windows

For each Menu Bar item, there is a pull-down menu associated with the

item (Section 2.2). To access an item in the menu, the user must point the

mouse cursor over the desired item and click MB1. A pop-up window will

then be displayed and ready for data editing. Due to the variety of data

entry requirements, pop-up windows have several different layouts and

characteristics.

2.4.1 File Box Popup

This type of window displays a list of files which the user may open, load,

append, or save. To access a file, point the cursor to the desired filename

and double-click the desired item with MB1. One example of a File Box

Pop-up is the Open window, which is activated by selecting Open from

the File menu.



2.4.2 Text Entry

The sole function of a text-entry window is to accept the text information

as entered. An example of this kind of window is the System Info item in

the Config menu. This window provides a place for the user to enter

descriptive information to identify the simulation input data.



2.4.3 Single Item Selection Panel

A single item selection panel is displayed in a single column format and

the selection items are displayed with the corresponding help message.

Only single selection is allowed at a time. To make a selection, the user

move the mouse pointer to the diamond button beside the desired item

and click with MB1 and then click the OK button. One example is the EOS

option in the Config menu for an equation-of-state selection.

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2.4.4 Multiple Item Selection Panel

A multiple item selection panel is displayed in a multiple column format

and more than one selection may be made at one time. The selection items

are displayed in two different ways. In one instance the options have a

rectangular push button beside each option, and the user may select as

many as needed. An example of this type of panel is the Laboratory Tests

Selection Panel as shown in Figure 2-1. The other type of multiple

selection is with a square toggle button. The square toggle button may be

clicked with MB1 which will toggle the option on and off. An example of

this type of panel is the Fluid Component Selection Panel (Figure 2-2).

Figure 2-1: An Example of Rectangular Push Buttons for Multiple ItemSelection Panel

Figure 2-2: An Example of Square Toggle Buttons for Multiple Item SelectionPanel

RectangularPushButton

SquareToggleButton

R2003.0 - Landmark 2-11


2.4.5 Option Flag/Confirm Dialog

An option-flag or confirm dialog window provides a mechanism for users

to toggle on/off certain simulation configurations. The standard setup for

this kind of window is a Yes/No question dialog box. For example, the

Regression item in the Config menu allows the user to turn on/off the

automatic parameters adjustment feature.

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2.4.6 List Entry Panel

A list entry panel provides a place for users to enter and edit data. The

window is displayed in a single column fashion. The window allows the

user to scroll data by using the slider bar, when applicable. An example

for the list entry panel is the test data entry for saturation pressure

calculation. Three types of data may exist in these windows:

■ Numeric Data - The data displayed in the data entry field can be an

integer or a real number.

■ Alphanumeric Menu Item - Text is displayed in the data entry field. By

pressing MB3 a list of options will be displayed from which to choose

the desired item.

■ Cascade Table Entry - When the data entry box indicates more data is

available, the user can access it by pressing the F5 function key or

clicking the button with MB1 while the mouse cursor is on the desired

box cell.

CascadeTableEntry

NumericDate

AlphanumericMenu Item

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2.4.7 Rectangular List Entry Panel

This type of window provides a multiple-column, multiple-row table for

editing data. This window allows the user to scroll and edit data by using

the slider bar on either side of the table.

One example of rectangular list entry panel is the EOS component

properties table. The size of the component properties table is fixed once

the equation of state and the components are specified. The user cannot

change the table size inside the window.

For certain rectangular data entry windows, the size of the table may be

dynamically varied inside the window. An example of these dynamic

windows is the table for entering laboratory measurements in the

saturation pressure calculations. In this table, the number of columns (for

temperature stages) can be increased by pressing the AddColAfter or

AddColBefore button, and reduced by pressing the DeleteCol button.

Slider Bar

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2.4.8 Triangular Table Entry Panel

This type of window provides a special table format to deal with

symmetric matrix data entries. One example is the window for component

binary interaction coefficients as shown below. Since these entries are

symmetric with the diagonal, DESKTOP-PVT will display the lower

triangular portion and only allow cursor movement in this area. This

window allows the user to scroll and edit data by using the slider bars.

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2.5 Invoke Calculation

After the user sets up the input data, either by importing a batch data file

or direct data entry, DESKTOP-PVT is ready to perform the calculation

task. The user can invoke the phase behavior calculations by selecting Go

from the Run menu.

2.6 Get Results

DESKTOP-PVT provides an interactive graphics environment for the user

to manipulate the calculation results in graphical form. The user can

review the results on a graphic terminal and manipulate them before

dumping the graphics to hardcopy devices. The graphic results can be

saved into a metafile for future reference, if desired.

2.7 File Type

Due to the complexity of the file requirements, six different types of files

are used in DESKTOP-PVT.

2.7.1 Batch Data File

A batch data file is a text file (i.e., in ASCII format), which is used as an

input data file for DESKTOP-PVT phase behavior calculations. A batch

data file can contain input data such as component equation-of-state

properties, regression variables, and laboratory measured data, etc. This

kind of file can be accessed by an operating system editor, for example, the

vi text editor in the unix system. The data entries in a batch data file

should comply with the format described in the companion reference

manual, DESKTOP-PVT Keyword Reference Manual.

A batch data file can be created either through the Save process in

DESKTOP-PVT, i.e., by selecting Save from the File menu, or the editing

process using an operating system editor. The Save process will convert all

input data in memory into a proper keyword format. The data will be

stored in a file with a name specified by the user. On the other hand, the

user may select Open from the File menu to load data in a batch data file

into memory.

Although there is no strict restriction on the filename specification, the

total length of the filename should not exceed twelve letters. The filename

should comply with the rules of the operating system. The default file

extension for batch data files in DESKTOP-PVT is ".dat", which is also

used as the default searching pattern during the file listing step in the

Open file process.

A batch data file can be used for a direct batch process run as discussed in

Section 2.1.

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2.7.2 Database File

A database file stores information in a random access format, i.e., in binary

format. Both input data and calculated results are saved in a database file.

One advantage of using database files is that the data can be accessed

more efficiently. It also provides a mechanism for users to access results

from previously calculated runs without reactivating the calculation

process. Database files also serve as a buffer for handling intermediate

data during the data entry process.

Load Database and Save Database in the File menu are used to manipulate

the database files. With the exception of the target file extension, the basic

functions of the Load Database and Save Database are the same as the

Open and Save processes, respectively. The default file extension for the

database files in DESKTOP-PVT is ".dbf", which is also used as the default

searching pattern during the file listing step in the Load Database file

process.

SavGraph and GetGraph in the Report menu work the same as Load

Database and Save Database, respectively. Both processes access a

database file and prepare the data for manipulating the results under an

interactive graphics environment.

2.7.3 EOS Data File

An equation-of-state (EOS) data file contains component EOS properties

such as molecular weight, critical temperature, critical pressure, and

composition (in mole fraction), etc. The EOS data files may serve as an

interface to a compositional reservoir simulator such as VIP-COMP. The

file is in ASCII format, i.e., a text file, which is arranged to comply with the

format of the VIP simulators. This data file can be generated in three ways:

■ Heavy Fraction Characterization

■ Pseudoization Process

■ Regular Run

DESKTOP-PVT also provides mechanisms to read EOS data file so that the

EOS data generated in the previous runs can be used as the initial input

for the next run. See Sections 5.1.5 and 5.1.6 for details of reading EOS data

files.

R2003.0 - Landmark 2-17


2.7.4 Report Text File

Once calculations are completed, DESKTOP-PVT will generate an output

file in text format. This file is accessible through the system editor and can

be sent to a line printer for obtaining a hardcopy. The user can review this

file by selecting Table from the Report menu without leaving the

DESKTOP-PVT environment. This task is accomplished by invoking a

system editor to access this file through a subprocess mechanism. The file

can also be sent to a system line printer directly by selecting PrtTable from

the Report menu.

2.7.5 PostScript Output File

A PostScript output file is generated for printing on a PostScript printer

when the PRINTER option is chosen. The output filename will be set to

the environment variable VIPPSOUT (or “psout.ps" if it is not defined).

The output file is automatically routed through the print queue, defined

by VIPPRINTER, to the printer defined by the environment variable

VIPPOST.

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Chapter

3

Input Data File

3.1 Introduction

The File menu in the Menu Bar provides a means for creating, saving and

retrieving files containing simulation input data and results. There are

seven selection items in this menu:

■ Last Run

■ Open

■ New

■ Save

■ Load Database

■ Save Database

■ Exit

3.2 Last Run - Recall Data From Backup File

The Last Run option is used to recall the input data from the most recent

simulation run. This option is activated by selecting Last Run from the File

menu. No data entry is required. To recall data from the last run,

DESKTOP-PVT reads input data from the file dtpvt.ini which is saved

when the user exits DESKTOP-PVT normally by selecting Exit from the

File menu. In addition, this file is also created for the simulator’s

calculation engine while the user activates the calculation process. In this

way, the user will have a backup copy of input data after a system crash.

These options allow the user to quit DESKTOP-PVT simulation

temporarily without losing his current input data set.

R2003.0 - Landmark 3-19

Input Data File DESKTOP-PVT USER’S GUIDE

3.3 Open - Load Batch File Data

The user can view a list of input data files in the working directory, and

instruct DESKTOP-PVT to read a specified file using the Open option. By

default, DESKTOP-PVT will list all files with the file extension ".dat" in the

working directory. To select and read an input data file, select the desired

item by clicking the file name with MB1 and then click the Ok button.

Before loading the data into memory, DESKTOP-PVT checks the contents

and format of the file. DESKTOP-PVT will display a warning message if

erroneous data is detected.

3.4 New - Initialize Data To Default Values

Unlike the Open option, no files will be opened when the New option has

been selected. The main purpose of the New option is to initialize all data

in memory to the DESKTOP-PVT default values. This option allows the

user to redesign the simulation conditions from scratch. The New option

is automatically processed each time the user activates DESKTOP-PVT;

therefore, it is not necessary to select New to load the default values for a

fresh simulation. No additional data entry is required.

3.5 Save - Save Data Into Batch Data File

The Save option allows the user to save the input data currently in

memory to a file in the working directory. The user is asked to enter a file

name. A maximum length of twelve letters is allowed for an input data file

name. DESKTOP-PVT lists input data files with the extension ".dat" by

default in the Open process. It is recommended that the file extension .dat"

be used when saving an input data file.

3.6 Load Database - Load Data From Database File

The Load Database option is similar to the Open option, except now a

database file is read and loaded into memory. A database file contains

input data and simulation results. The default database file extension is

".dbf", and by default these files are automatically listed when the Load

Database option is selected.

3.7 Save Database - Save Data To Database File

The current input data and simulation results can be saved in a database

file using the Save Database option. The user is asked to enter a file name

with a maximum length of twelve letters. This option works very similar

to that of the Save option, except now a database file is saved. It is

recommended that the file extension ".dbf" be used to name a database

file.

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DESKTOP-PVT USER’S GUIDE Input Data File

3.8 Exit - Terminate DESKTOP-PVT

The Exit option allows the user to exit DESKTOP-PVT normally. No data

entries are required. In addition to terminating the working environment,

DESKTOP-PVT automatically saves the current data in memory in a file

named dtpvt.ini. The file dtpvt.ini can be loaded into memory through

the Last Run option.

R2003.0 - Landmark 3-21

Input Data File DESKTOP-PVT USER’S GUIDE

3-22 Landmark - R2003.0

Chapter

4

Setup Simulation Environment

4.1 Introduction

The major function of the Config menu is to define the global simulation

environment. Through the Config menu selections, the user dictates the

required input and the calculations DESKTOP-PVT will perform later. The

simulation details, however, are not required to input at this stage. For

example, the Regression entry in the Config menu is used to activate (or

deactivate) the DESKTOP-PVT nonlinear regression function which

allows automatic adjustment of the equation-of-state properties of

individual components. When the Regression option is on (activated), the

corresponding menu for nonlinear regression will be displayed on the

Menu Bar entitled Regres. The Regres menu requires the specification of

regression parameters.

There are twelve items under the Config menu.

■ System Info

■ EOS

■ Binary Coeff

■ Test Type

■ Regression

■ Pseudoization

■ Thermal

■ Water-In-Oil

■ Heavy

■ Run-Time Compos

■ Composition Sor

■ Run Sequence

R2003.0 - Landmark 4-23

Setup Simulation Environment DESKTOP-PVT USER’S GUIDE

Two of the items, Composition Sor and Run Sequence, will be displayed

only if the Pseudoization and Run-Time Compos options are activated,

respectively. Because of their calculation features, the functions of

Regression, Pseudoization and Heavy are mutually exclusive, i.e., only

one of the three functions can be activated at a time.

4.2 System Info - Add Descriptive Text For Data Set

The System Info option allows the user to add descriptive text to identify

the current data set. A maximum of 10 lines with 50 letters each is allowed.

4.3 EOS - Equation-of-State Selection

The EOS option is for the equation-of-state (EOS) selection. The specified

equation-of-state will be used to describe the fluid properties for all

laboratory procedures. The available equations of state include Peng-

Robinson (PR), Original Peng-Robinson (PRORIG), Soave-Redlich-Kwong

(SRK), Redlich-Kwong (RK), Zudkevitch-Joffe-Redlich-Kwong (ZJRK),

and the three-parameter (3P) versions of PR, SRK and RK. The default is

the Peng-Robinson equation of state (PR).

Figure 4-1 shows the EOS selection panel. To make a selection, the user

clicks the diamond button next to the desired item, and then click the Ok

button.

Figure 4-1: EOS Item Selection Panel

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DESKTOP-PVT USER’S GUIDE Setup Simulation Environment

4.4 Binary Coeff - Binary Interaction Coefficients Options

Two methods are available for defining binary interaction coefficients (djk)

in DESKTOP-PVT. The Binary Coeff option is used for this selection. The

binary interaction coefficients are read in explicitly if the "YES" option is

selected, otherwise they are computed from a correlation. The default is to

read djk explicitly.

A triangular table under the Binary Coeff item of the Fluid menu is

provided for data entry if djk is read in explicitly. Otherwise, the binary

interaction coefficients are computed using the correlation

where vcj and vck are the critical volumes for component j and k,

respectively, and djkcor is an input exponent.

4.5 Test Type - Laboratory Tests Selection

The Test Type option is used to specify the simulated laboratory test

procedures. Figure 4-2 shows the Test Type selection panel. The user must

select at least one test procedure. Both multiple selections of the various

laboratory procedures, and multiple runs of a laboratory procedure are

allowed. A maximum of nine runs is allowed for each test procedure. The

total number of runs for all test procedures cannot exceed twenty-four.

Figure 4-2: Test Type Selection Panel

The numerical key 1 can be used to specify one run for a selected test

procedure or the user can click the name of the desired item and an

asterisk will appear in the cell box. The asterisk indicates that one test run

has been defined. To specify multiple runs for a test procedure, the

numerical keys 2 to 9 are used to edit the number of runs in the data entry

field to the left of the test type name. Whenever any data exists in the data

entry field, click the test type name button to clear the field.

djk 12vcj

1 6⁄vck

1 6⁄⋅

vcj1 3⁄

vck1 3⁄

+----------------------------

djkcor

–=

R2003.0 - Landmark 4-25


The available laboratory procedures are:

■ Z-factor. Gas compressibility factor (Z-FACTOR)

■ Density. Liquid density (LIQDEN)

■ Vapor Pressure. Vapor pressure of a pure component (VP)

■ Sat Pressure. Saturation Pressure (dew point or bubble point) of a

mixture (PSAT)

■ Viscosity. Liquid and gas viscosity (VISC)

■ Cnst Composition. Constant composition expansion procedure

(CCEXP)

■ Cnst Volume. Constant volume depletion procedure (CVDEP)

■ Swelling. Swelling test procedure (SWELL)

■ Differential. Differential expansion procedure (DIFF)

■ Multi-Contact. Multiple contact vaporization test (MCVAP)

■ Phas Envlop/Psat. Phase envelope calculation (dew point and bubble

point calculation) (ENVELOPE)

■ Gas Enthalpy. Gas enthalpy (ENTHV)

■ Liquid Enthalpy. Liquid enthalpy (ENTHL)

■ Water Property. Liquid water properties of density, enthalpy, viscosity

and fugacity coefficient (WATPRP)

■ Sat Pressure/H2O. Bubble point pressure of a mixture in the presence

of water (PSATW)

■ Distillation. Distillation test (DISTIL)

■ Steam Distillatn. Steam distillation procedure (STMDIS)

■ Separator/No Reg. Multistage separators without regression option

(SEPARATOR)

■ Separator/Reg. Laboratory separator test with regression option (SEP)

■ Phas Envlop/Full. Complete phase envelope calculation (ENVPT)

4-26 Landmark - R2003.0


■ ZGRAD. Composition variations with depth (ZGRAD).

■ CO2TAB. Properties of CO2 saturated water (CO2TAB).

■ Steam Vaporizatn. Multiple contact steam vaporization (MSCVAP).

■ Two Phase Flash. Isothermal two phase flash (FL2I).

4.6 Regression - Automatic Parameter Adjustment Option

The Regression option is used to activate (or deactivate) the nonlinear

regression function for automatic adjustment of the equation-of-state

properties of individual components. The default is no regression. When

the regression option is activated, the data entry menu for nonlinear

regression will be displayed on the Menu Bar entitled Regres. The user

must specify the regression parameters in the Regres menu.

4.7 Pseudoization - Pseudoization Option

Pseudoization is a calculation procedure used to combine and reduce

original fluid components to a pseudo system by specifying which of the

original components will be lumped into which pseudo component. The

Pseudoization option in the Config menu is used for selecting this option.

The default is no pseudoization calculations. Similar to the Regression

option, a data entry menu for pseudoization calculation will be displayed

on the Menu bar entitled Pseudo.

In DESKTOP-PVT, pseudoization can be performed as a stand-alone

calculation, or in conjunction with laboratory procedures. An additional

selection item, Composition Sor, will be displayed in the Config menu if

the pseudoization option is activated. Figure 4-3 is an example of the

Composition Sor List Entry Panel. This option is used to specify the fluid

composition (source) of laboratory procedures either as unpseudoized

(Original selection) or pseudoized (Pseudo selection) when pseudoization

is run together with laboratory procedures. Regardless of any Pseudo

selections in the Composition Sor window, the pseudoization calculation

will be performed if the Pseudoization option is activated. The

pseudoization input requirements and the procedures for stand-alone

pseudoization are discussed in Chapter 6.

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Figure 4-3: Composition Sor List Entry Panel

4.8 Thermal - Thermal Application Option

The Thermal option is a thermal application function designed for VIP-

THERM. By default, this option is not activated. The Thermal option is

restricted to Peng-Robinson equation of state when activated.

Two special actions will be taken when this option is activated. First, a

special equation-of-state PVT properties file for VIP-THERM will be

created. Second, extra menus for binary interaction coefficients of H2O

(water) and other fluid components, both in regression variables (Regres

menu) and fluid properties (Fluid menu) assignments, will be displayed.

These menus allow the user to specify the binary interaction coefficients of

H2O and other components even if H2O is not specified as a component.

Furthermore, DESKTOP-PVT will load other H2O equation-of-state

properties automatically for thermal applications.

These binary interaction coefficients and H2O properties are pertinent

only to the steam distillation test, multiple contact steam vaporization test

and saturation pressure calculation with water.

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4.9 Water-In-Oil - Water in Oil Option

The Water-In-Oil option is a thermal application function designed for

VIP-THERM. Using the Water-In-Oil option, water may be allowed to

partition into the oil phase in the multiple contact steam vaporization test,

steam distillation test, and the saturation pressure with water calculation.

In all of these tests, water is an implicitly defined component and, for VIP-

THERM applications, should not be defined as a component by the user in

the component properties data. Other tests are not affected by the

selection of this option. By default, this option is not activated. The Water-

In-Oil option can be turned on (Yes Selection) only if the Thermal option is

activated.

4.10 Heavy - Heavy Fraction Characterization Option

The Heavy option is used to perform a heavy fraction characterization

from laboratory measured properties of the heavy fraction. The heavy

fraction characterization procedure is a stand-alone calculation, and

cannot run with other calculations. By default, this option is not activated.

Refer to Chapter 6 for more information regarding the heavy fraction

characterization.

4.11 Run-Time Compos - Run-Time Composition SpecificationOption

There are two options available for specifying unpseudoized fluid

compositions (mole fractions) in DESKTOP-PVT. Usually, the fluid

compositions are entered directly for each laboratory procedure under the

Composition entry of the test data window. In some cases, the

composition required for a test calculation is actually the vapor, liquid, or

overall composition of some intermediate step in another laboratory test.

The Run-Time Compos option is provided for these special applications.

The default for this option is No, and all fluid compositions should be

entered directly.

The laboratory tests for which this composition specification is available

include constant composition expansion, constant volume depletion,

swelling, differential expansion and composition variations with depth.

The restriction for the intermediate step composition specification is that

the reference to the composition from a type of test must pertain to the

most recently entered test of that type in the data stream.

The Run Sequence option, which will be displayed when the Run-Time

Compos option is activated, is used for the "referenced" composition

specifications. Figure 4-4 is an example of the Run Sequence window. In

this window, the first column lists the laboratory procedures (Test), and

the second column displays the run numbers (Run ID) for each laboratory

procedure. Data may not be entered in these columns. The third column

R2003.0 - Landmark 4-29


(Intermed Comp) is used to specify if the composition of a test calculation

is from the Liquid, Vapor, or Overall composition of some intermediate

step in another test. The default is to enter composition directly (Noselection). Numerical numbers are entered in the Run Sequence entries to

specify the order of the test runs. A smaller number has a higher priority

in the run sequence. The user must pay special attention to the run order,

i.e., a test must be run before its liquid, vapor, or overall compositions can

be referenced by other tests.

Figure 4-4: Run Sequence Panel

4-30 Landmark - R2003.0

Chapter

5

Equation-of-State Properties

5.1 Component

The Component menu allows the user to define the components of the

fluid system used for phase behavior simulation. The component

information is one of the bases of the fluid system. Many input data in

DESKTOP-PVT are dependent upon components specification. Thus,

components should be defined before accessing other data screens. There

are six items available in the Component menu for defining fluid

components:

■ System

■ User

■ Volatile

■ Composition

■ Load EOS

■ Append EOS

5.1.1 System - Select Component From System Default Table

The System option in the Component menu allows the user to select

components whose properties are internally coded in DESKTOP-PVT.

Default properties, such as critical properties, binary interaction

coefficients, and ideal gas state enthalpy coefficients, will be automatically

loaded upon exiting this menu. These properties can be edited to override

the default values.

Upon selecting the System option, a multiple item selection panel

(Figure 5-1) will be displayed. The panel contains system-defined

component names. Select the options by clicking the square button next to

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Equation-of-State Properties DESKTOP-PVT USER’S GUIDE

the desired option. When finished, click the OK button to return to the

display window.

Figure 5-1: System-Defined Component Panel

5.1.2 User - Make User-Defined Component

The User option in the Component menu allows the user to define

components different from those of system-defined. The component

properties, however, are not supplied by the program and the user must

provide the component properties in the Fluid menu for each component.

In the user-defined fluid component table, click the AddRowAfter (or

AddRowBefore) button to add components, and click the DeleteRow

button to remove components (Figure 5-2). For each added component,

the user must give a name that is different from the System. If a name is

5-32 Landmark - R2003.0

DESKTOP-PVT USER’S GUIDE Equation-of-State Properties

not given, DESKTOP-PVT will automatically assign a default name

starting with "USR".

Figure 5-2: User Defined Fluid Component Table

5.1.3 Volatile - Define Volatile Component

Volatile is a special option for thermal applications. This option is used to

select the volatile components for thermal simulations, i.e., steam

distillation and bubble point pressure calculation of a mixture in the

presence of water. All components are volatile by default. To select a

volatile component, click the square button next to the desired button.

Figure 5-3 is an example of the volatile component selection panel.

Figure 5-3: Volatile Component Selection Panel

5.1.4 Composition - Global Reference Composition

The fluid composition is a required input for all laboratory test

procedures. DESKTOP-PVT provides a mechanism so one test can load

the composition directly from another test. The Composition item

provides a global buffer for all tests to access a common composition.

When the user opens a batch data file the global composition is loaded

R2003.0 - Landmark 5-33


with the composition of the first test. Figure 5-4 is an example menu for

entering global composition.

Figure 5-4: Global Reference Composition Panel

5.1.5 Load EOS - Load Component From File

The Load EOS option is used to open an EOS data file and load its

information into memory. An EOS data file contains information such as

component names, component critical properties, component

composition, etc. The user needs to be aware that all component data in

memory will be replaced on activating Load EOS. This option can be used,

for example, to import the component properties from a previous

(pseudoization or regression) run as the fluid properties for the next run

(e.g. different test procedures or temperatures).

The Load EOS option works similarly to the Open option in the File menu,

except now an EOS data file is read and loaded into memory. The default

EOS file extension is ".eos", and by default these files are automatically

listed on activating Load EOS.

5.1.6 Append EOS - Append Component From File

Different from Load EOS, the option Append EOS will access the data

contained in an EOS file and append its information to the current fluid

description. The components in the file will be merged into the current

component pool. The Append EOS procedures are the same as those of

Load EOS.

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5.2 Fluid Properties

Fluid Properties data are entered to define the PVT characteristics of

individual components. These are combined by appropriate mixing rules

and used with the equation of state to determine the properties of

mixtures. Default properties for system-defined components, as discussed

in Section 5.1.1, are internally coded. However, the user may elect to

override the defaults.

There are nine items in the Fluid menu.

■ Property

■ Binary Coeff

■ Binary Exponent

■ H2O Binary Coef

■ Gas Enthalpy

■ LBC Visc

■ Pedersen Visc

■ K-Value Correl

■ CO2TAB Correl

These items can be accessed only if fluid components have been defined in

the Component menu, as described in Section 5.1. The following sections

discuss the options on this menu in more detail.

R2003.0 - Landmark 5-35


5.2.1 Property - EOS Property

The Property option in the Fluid menu is used to access the component

EOS properties. After selecting Property, three items will be listed in the

data entry window (Figure 5-5). However, five items will be displayed if a

three-parameter equation-of-state has been specified.

Figure 5-5: Equation-of-State Properties

Temperature & Pressure Unit

The first two items are used to define the temperature and pressure units

for values in the property table. To select the temperature or pressure unit,

the user may either type the options in directly or click the entry cell with

MB3 to access an option window. When the option window is accessed,

click the diamond button next to the desired item and click the OK button

to return to the previous menu.

Property Table

The table entries are dependent upon the equation-of-state being selected

in the Config menu. When selected the Property Table will display a

rectangular table for entering critical properties. In general, there are eight

entries for each table:

■ MW. Molecular weight.

■ Tc. Critical temperature.

■ Pc. Critical pressure.

■ Zc. Critical z-factor.

■ Acentric. Acentric factor.

■ Omega A. Omega A.

■ Omega B. Omega B.

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■ Parachor. Parachor, .

For a three-parameter EOS, there is one more table entry available:

■ Vshft. Volume shift parameter.

For ZJRK EOS, three more table entries are available:

■ Tb. Normal boiling temperature.

■ Spec Grav. Specific gravity of component at Tref.

■ Tref. Reference Temperature for specific gravity.

The default values for system-defined components are loaded

automatically while they are defined as described in Section 5.1.1, yet the

user can elect to override those values in this table. For user-defined

components, however, the user should supply at least the molecular

weights. The properties left as zero will be considered as the default

values, and the program will apply table look-up through molecular

weight to calculate these default properties while the user leaves the

property table. The program also provides a mechanism such that the user

can manually load up the default values for cursor-positioned component

by pressing the F2 function key. Figure 5-5 shows an example of the

property table.

Figure 5-6: EOS Property Table

g1 4⁄

cm3⋅

s1 2⁄

mole⋅---------------------------

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Volume Shift Parameters (D & E)

If the user selects a three-parameter EOS, two additional items, D and E,

will be shown on the property data window for editing. These parameters

D and E are used to compute volume shift parameter, s,

where MW is component molecular weight.

5.2.2 Binary Coeff - Binary Interaction Coefficients

The binary interaction coefficients (djk) are used in the mixing rules that

determine the A parameter of the EOS. Two methods are available for

defining djk’s in DESKTOP-PVT. The Binary Coeff option in the Config

menu is used to specify how djk’s will be defined (see Section 4.4). The

Binary items in the Fluid menu is dependent on the option selected by the

user. If the flag for the Binary Coeff item of the Config menu is set to YES,

the Binary Coeff option will be highlighted in the Fluid menu, otherwise

the option Binary Exponent will be highlighted.

The Binary Coeff option in the Fluid menu allows the user to edit djk data

explicitly. A window with a triangular djk data table will be displayed for

editing data. A list of component names defined in the Component menu

will be displayed at the top of the table, except for the last component. The

first column will display the component names without the first

component. The F2 function key can be used to load the default djk’s for

the entire data row where the cursor is positioned. The default djkbetween system-defined components will be automatically loaded when

they are selected in the Component menu. All binary combinations

between nonsystem-defined components will be assigned default values

of zero.

If the Thermal option is activated (Section 4.8), the H2O Binary Coef menu

will be displayed. This menu allows the user to specify the binary

interaction coefficients of H2O and other components even if H2O is not

specified as a component explicitly.

The Binary Exponent option in the Fluid menu provides another means

for defining djk values. In this option, all binary interaction coefficients

are computed using the correlation

where vcj and vck are the critical volumes for component j and k,

respectively, and djkcor is an input exponent. Selecting the Binary

s 1 D MWE–⋅–=

djk 12vcj

1 6⁄vck

1 6⁄⋅

vcj1 3⁄

vck1 3⁄

+----------------------------

djkcor

–=

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Exponent option will display a data window for entering djkcor (Figure 5-

7). The default value of djkcor is 1.0.

Figure 5-7: Binary Exponent Panel

5.2.3 Gas Enthalpy - Ideal Gas State Enthalpy Coefficients

The Gas Enthalpy option in the Fluid menu allows the user to define

component ideal gas state enthalpy coefficients. The ideal gas state

enthalpy for each component is computed by the fifth degree polynomial

where Hi is the ideal gas state enthalpy of component i in Btu/lb-mole, Tis the temperature in degree Rankin, and hin is the ideal gas state enthalpy

coefficient of component i in Btu/lb-mole-(R)n.

The pure component Passut-Danner ideal gas state enthalpy coefficients

have been internally coded. These values will be automatically loaded

when the corresponding component names are selected in the Component

menu. For all other components, default ideal gas state enthalpy

coefficients are calculated using the Kesler and Lee correlation. This

correlation is not always applicable. It fails if the component critical

temperature is less than 60 ˚F. The correlation requires component specific

gravity. If the component is a gas at standard conditions, then the density

at the vapor pressure at standard temperature is used. For the relatively

heavy components commonly used in thermal reservoir simulation, these

shortcomings are not a problem. Any of the default values for ideal gas

state enthalpy coefficients may be overriden by the user. On selecting the

Gas Enthalpy option, a data entry window will be displayed (Figure 5-8),

Hi hio hi1+ T hi2+ T2

hi3+ T3

hi4+ T4

hi5+ T5⋅ ⋅ ⋅ ⋅ ⋅=

R2003.0 - Landmark 5-39


and the user can edit the gas enthalpy coefficients, hin, for each

component.

Figure 5-8: Gas Enthalpy Panel

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5.2.4 LBC Visc - Lohrenz-Bray-Clark Viscosity Correlation

00 The Lohrenz-Bray-Clark viscosity calculation is as follows:

00

00 where is the phase viscosity, is a base viscosity, is a function of

pseudo critical pressures, pseudo critical temperatures, and mixture

molecular weight, and is a pseudo reduced phase density.

00 By default, the coefficients are:

00 C1 = 0.1023

C2 = 0.023364

C3 = 0.058533

C4 = -0.040758

C5 = 0.0093324

The user may change these default coefficients by selecting the LBC Visc

menu item, and changing the value in the dialog box (Figure 5-9).

Figure 5-9: Coefficients of Lohrenz-Bray-Clark Viscosity Correlation

µ µb ζ C1 C2ρr C3ρr2

C4ρr3

C5ρr4

+ + + +[ ]4

104–

–( )+=

µ µb ζ

ρr

R2003.0 - Landmark 5-41


5.2.5 Pedersen Visc - Pedersen Viscosity Correlation

The Pedersen et al. viscosity correlation is based on the corresponding

states principle. A group of substances obeys the corresponding states

principle if these substances have the same reduced viscosity at the same

reduced density and reduced temperature. In such case, only

comprehensive viscosity data for one component (the reference

component) in the group are needed. Others can be calculated from the

reduced viscosity. The Pedersen et al. viscosity correlation uses methane

as a reference substance.

This correlation is useful for heavy oils where the Lohrenz-Bray-Clark

correlation fails to give a proper viscosity prediction for some cases. To

invoke the Pedersen et al. viscosity option, the VISPE option should be

selected in the Calc Method menu. The user has the option of specifying

the k-coefficients, k1 to k7 (Figure 5-10), for calculating the viscosity of the

reference component and binary interacting coefficients Xkj (Figure 5-11)

for calculating the mixture pseudo-critical temperature used in the

viscosity correlation. The default values are zero for all the interacting

coefficients Xkj and the following values for the k-coefficients.

k1 = 9.74602

k2 = 18.0834

k3 = 4126.66

k4 = 44.6055

k5 = 0.976544

k6 = 81.8134

k7 = 15649.9

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Figure 5-10: k-coefficients of Pedersen Viscosity Correlation

Figure 5-11: Tc-Binary Interaction Coefficient of Pedersen Viscosity Correlation

R2003.0 - Landmark 5-43


5.2.6 K-Value Correl - Component K-Value Correlation

In DESKTOP-PVT the component K-values are usually computed using

an equation of state. For distillation test, a correlation is available to

compute K-values of distillates.

The component K-value is expressed as

(5-1)

where Ai to Ei are constant coefficients for component i, P is pressure in

psia and T is temperature in Rankin. Figure 5-12 shows an example of the

data entry table for the component coefficients of the K-value correlation.

Figure 5-12: Component Coefficients of K-Value Correlation

5.2.7 CO2TAB Correl-Correlation of CO2 Saturated Water Properties

Correlations were developed to calculate properties of carbon dioxide

saturated water as functions of temperature, pressure and salinity. These

properties include carbon dioxide solubility, formation volume factor,

compressibility and viscosity.

Figure 5-13 shows the main data entry menu for entering correlation

coefficients of carbon dioxide saturated water properties. The selection

items are for the correlation of carbon dioxide solubility in pure water, the

correlation to adjust the effects of salinity on carbon dioxide solubility in

water, and the correlation to calculate density of carbon dioxide saturated

Ki Ai

Bi

P----- Ci P⋅+ + EXP

Di–

T Ei–---------------

⋅=

5-44 Landmark - R2003.0


water. The density correlation is used in computing water formation

volume factor.

Figure 5-13: Correlation Coefficients of Carbon Dioxide Saturated WaterProperties

Figure 5-14 shows the data entry table for entering correlation coefficients

of solubility of carbon dioxide in pure water. The coefficients are a0 to a4,

b0 to b4, and c0 to c4 to be discussed next. Default values are available for

all coefficients.

Figure 5-14: Correlation Coefficients of Solubility of Carbon Dioxide in PureWater

The solubility of carbon dioxide in pure water is calculated as a function of

temperature and pressure.

Rsw a P 1 bπ2--- c P⋅

c P 1+⋅--------------------⋅

sin⋅–⋅= if P Po<

R2003.0 - Landmark 5-45


and

where

with Rsw in scf of carbon dioxide per stb water, temperature (T) in degree

Fahrenheit, pressure (P) in psia and

a0 =1.16306, a1 =-16.6304, a2 = 111.07305, a3 =-376.85925, a4 =524.88916

b0 =0.96509, b1 = -0.27255, b2 = 0.09234, b3 = -0.10083, b4 = 0.09979

c0 =1.28030, c1 =-10.75660, c2 = 52.69622, c3 = -222.39488, c4 =462.67255

This correlation matches the solubility data of Wiebe (1941)1 for liquid and

supercritical carbon dioxide in water within ±10 scf/stb for temperatures

between 54 and 212 degrees Fahrenheit and pressures up to 10,000 psia.

The calculated solubility in pure water is further adjusted for the effects of

salinity to obtain the solubility of carbon dioxide in brine

Rsw Rswo

m P Po

–( )⋅+= if P Po≥

a ai 10 3– T⋅( )i⋅i 0=

4

∑=

b bi 10 3– T( )i

i 0=

4

∑= and 0 b 1< <

c 10 3– ci 10 3– T( )i

i 1=

4

∑⋅=

po 2

π--- b

2( )sin 1–

c 12π--- b

2( )sin 1––

--------------------------------------------⋅=

Rswo

a Po

1 b3

–( )⋅ ⋅=

m a 1 bπ2--- c P

o⋅c P

o1+⋅

---------------------- π

2--- c P

o⋅c P

o1+⋅

---------------------- π2--- c P

o⋅c P

o1+⋅

----------------------

cos⋅+sin⋅–

=

Rsb

Rsw--------

log soS Ts1=

5-46 Landmark - R2003.0


where S is salinity of brine in weight percent of solid, T is temperature in

degree Fahrenheit and

s0 = -0.028037

s1 = -0.12039

The measured data in NaCl Solutions from Malinin and Savelyeva (1972)2,

Malinin and Kurovskaya (1975)3, and McRee (1977)4 were used to obtain

parameters s0 and s1.

Figure 5-15 shows the data entry table for entering s0 and s1 coefficients

for adjusting the salinity effects on the carbon dioxide solubility in water.

Figure 5-15: Adjusting the Salinity Effects

The formation volume factor of carbon dioxide saturated water (or brine)

is calculated using

where d1 = 5.8, Bw is in rb/stb, ρw,sc is water density at standard

temperature in lb/cu ft and ρw,atm is water density at temperature and 14.7

psia in lb/cu ft. Both ρw,sc and ρw,atm are calculated using the correlation

from Rowe and Chou (1970)5. The correlation of carbon dioxide saturated

water density is developed using the data of Parkinson and De Nevers

(1969)6, and Sayegh and Najman (1987)7.

Bw1

ρw------ ρw sc, 0.02066 Rsb⋅+[ ]=

ρw ρw atm, 0.001 d1 Rsb⋅ ⋅+=

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Figure 5-16 shows the data entry table for entering coefficient d1 for

calculating carbon dioxide saturated water density. The default value is

5.8.

Figure 5-16: Calculating Carbon Dioxide Saturation Water Density

For pressures less than 5000 psia the water compressibility is calculated

using the correlation from Rowe and Chou (1970)5. For pressures greater

than 5000 psia,

where Cw,5000 is water compressibility at temperature and 5000 psia from

Rowe and Chou correlation in 1/psia. The above correlation is derived

from the water compressibility correlation by Osif (1988)8.

Water viscosity is calculated from Kestin et al. correlation (1978)9. The

effects of carbon dioxide solubility are ignored in both compressibility and

viscosity calculations.

1Cw------- 1

Cw 5000,------------------ 7.033 P 5000–( )+=

5-48 Landmark - R2003.0

Chapter

6

Heavy/Pseudo/Regres

6.1 Introduction

The mechanisms for assigning equation-of-state components and their

properties for a fluid mixture are discussed in Chapter 5. In this chapter,

we discuss three functions that can be used to obtain or modify some of

the component properties. These functions are represented by three items

in the main menu, i.e., Heavy, Pseudo, and Regres.

The Heavy function is used for calculating heavy fraction characterization

from laboratory measured properties for the heavy fraction. Pseudo is

used to reduce the original fluid system into a pseudo system by

specifying which of the original components will be lumped into which

pseudo component. Regres is a nonlinear regression package that

facilitates the adjustment of unknown or uncertain parameters that affect

fluid behavior. These menus are available only if their corresponding

option flags, Heavy, Pseudoization and Regression items in the Config

menu, are activated. Because of their distinctive calculation features, these

functions are mutually exclusive, i.e., only one of the three functions can

be activated at a time.

R2003.0 - Landmark 6-49

Heavy/Pseudo/Regres DESKTOP-PVT USER’S GUIDE

6.2 Heavy - Heavy Fraction Characterization

The Heavy menu on the Menu Bar is used for calculating heavy fraction

characterization from laboratory measured properties of the heavy

fraction. The program generates an extended analysis using a probability

distribution function that is based on user supplied heavy fraction

molecular weight and specific gravity. The extended analysis can be

pseudoized into a user specified number of components, or into a

program calculated number of components.

The heavy fraction characterization procedure is a stand-alone calculation.

The Heavy menu is available only if the Heavy option in the Config menu

is active. The Parameter option in the Heavy menu is used for entering

heavy fraction data. Once data entry is completed, Calculate is selected to

activate the calculation procedure. Graphics is used for reviewing the

results of the extended analysis in graphic mode. The equation-of-state

(EOS) properties of the pseudoized heavy fraction components can be

reviewed using Review. Save EOS is used to save the EOS properties of the

pseudoized heavy fraction components into a file. The EOS properties can

be added, or existing EOS properties can be replaced using Append EOS

or Replace EOS, respectively.

6.2.1 Parameter - Input For Heavy Fraction Characterization

Measured heavy fraction properties as well as calculation options are

entered using the Parameter option. At least three numbers, molecular

weight, specific gravity and mole fraction of the heavy fraction, must be

entered for heavy fraction characterization.

An extended analysis of the heavy fraction is calculated assuming the

carbon numbers in the heavy fraction follow a gamma distribution

function. The user must define the shape of the gamma function. For

example, the ALPHA entry for gamma function should be specified. By

default, ALPHA is 1. This gives an exponential distribution. Alpha values

should be in the range of 0.5 (accelerated exponential distribution) to 1.5

(skewed normal distribution).

The extended analysis can be entirely predictive or can be compared to

experimental distillation data. If distillation data of mole (or weight)

fraction distribution are available, an option can be activated to compute

an optimal ALPHA. This will minimize the differences between the

experimental and calculated distributions.

The gamma distribution function gives the mole fraction and molecular

weight for each single carbon number (SCN) of the extended fractions.

The calculated mole fraction and molecular weight of the last carbon

number in the extended analysis are adjusted so the computed mole

fraction and molecular weight of the heavy fraction are matched to the

observed data. The gamma function can be calculated using either a

constant molecular weight interval or variable molecular weight intervals.

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DESKTOP-PVT USER’S GUIDE Heavy/Pseudo/Regres

A constant Watson characterization factor is used for all carbon numbers

in the heavy fraction. If a Watson factor is entered, the input number is

used to compute the specific gravity of all carbon numbers. If a Watson

factor is not entered, this number is adjusted so the computed specific

gravity of the heavy fraction is matched to observed. Figure 6-1 is an

example of the Parameter Options Form.

Figure 6-1: Parameter Options Form

R2003.0 - Landmark 6-51


NOTE: To edit data indicated as <F5> on this form, either click MB1 over the

button next to the desired item or position the mouse cursor over the

box cell for the desired item to edit to make the F5 key accessible.

Any items that give you choice to make, move the mouse pointer

over the desired box cell and click MB3 to access a separate options

window. Choose the desired item and then click Ok to return to the

previous window.

■ Molecular Weight. The molecular weight of the heavy fraction. This isrequired input.

■ Specific Gravity. The specific gravity of the heavy fraction, measured

at 14.7 psia and 60 degrees Fahrenheit. This is required input.

■ Mole Fraction. The mole fraction of the total fluid sample contained in

the heavy fraction. This is required input.

■ Mole/Weight Fraction Option. Text label specifying the type of

distillation data. This is required input.

❑ WEIGHT. Weight fraction distribution

❑ MOLE. Mole fraction distribution (Default)

The WEIGHT option requires the user to enter the weight fraction

of the heavy fraction in the total fluid sample as well as the mole

fraction of the heavy fraction. The MOLE/WEIGHT option

controls whether mole or weight fraction distillation data should

be entered in the Distillation Data Table.

The program always calculates the mole fraction distribution

regardless of the option selected. The weight fraction distribution,

which is converted from the computed mole fractions, is calculated

only if the WEIGHT option is selected. This conversion requires

the user to enter the weight fraction of the heavy fraction in the

fluid sample. If the automatic ALPHA calculation option is

activated, the MOLE/WEIGHT option will control whether mole

or weight fraction data are used in computing optimal ALPHA.

■ Weight Fraction. The weight fraction of the total fluid sample

contained in the heavy fraction. Do not enter any number unless the

WEIGHT option has been selected. A number must be entered if the

WEIGHT option has been selected.

■ First Single Carbon No. The first single carbon number (FSCN) of the

heavy fraction to be considered in the extended analysis, i.e., for C7+enter 7, for C10+ enter 10. This number must be greater than 6. This isrequired input. (Default is 7)

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■ Last Single Carbon No. The carbon number of the last component to

be considered in the extended analysis for the heavy fraction. This isrequired input. (Default is 45)

■ Pseudo-Component No. & Name. The number and names of pseudo

component groups in the final fluid description for the heavy fraction.

The program will compute an optimal number of components if the

pseudo component groups are not specified. (Calculated by default)

■ Bracket M.W. for Grouping. Bracket molecular weights for the

purpose of regrouping the extended fractions into pseudo-

components. This table is available only if the number of pseudo-

components (Ng) for the extended fractions are defined in the Pseudo-

Component No. & Name entry. For a specified value of Ng, Ng-1

molecular weight values must be entered. For example, if Ng is 3, two

values must be entered. All extended fractions with molecular weight

less than or equal to the first value will be lumped into pseudo-

component 1. All extended fractions with molecular weight less than

or equal to the second value, but greater than the first, will be lumped

into pseudo-component 2. All remaining fractions will be lumped into

pseudo-component 3. (Calculated by default)

■ ALPHA, for Gamma Function. The alpha parameter in the gamma

distribution function. The gamma function becomes an exponential

distribution if alpha is 1. If alpha is less than one, the gamma function

is an accelerated exponential distribution. If alpha is greater than one,

it is a skewed normal distribution. This is required input. (Default is

1)

■ Regression on ALPHA (Y/N). Text label that activates the option for

automatic ALPHA calculation. If this option is activated, the

distillation data must be entered before calculation begins.

❑ YES. The ALPHA parameter in the gamma function is calculated

to minimize the differences between the experimental and

calculated values of distillation data. The input ALPHA parameter

is used as the initial estimate.

❑ NO. The input ALPHA parameter is used without any adjustment

for the extended analysis. (Default)

■ Max. ALPHA in Regression. The maximum ALPHA parameter

allowed during automatic adjustment. This value is used only if the

ALPHA regression option has been activated. (Default is 3)

■ Min. ALPHA in Regression. The minimum ALPHA parameter

allowed during automatic adjustment. This value is used only if the

ALPHA regression option has been activated. (Default is 0.5)

R2003.0 - Landmark 6-53


■ Maximum Iteration Number. The maximum number of iterations

allowed for automatic calculation of an optimal ALPHA parameter in

the extended analysis to match experimental distillation data. (Default

is 20)

■ Minimum Molecular Weight. The minimum molecular weight

expected to occur in the heavy fraction. The default value of 92 is

computed from

where FSCN is the default first single carbon number, 7, discussed

above. This is required input.

■ M.W. Interval Option. Text label specifying the type of molecular

weight interval used in calculating the extended analysis.

❑ CONSTANT. Constant molecular weight interval (Default)

❑ VARIABLE. Variable molecular weight interval

■ C6 to C7 M.W. Boundary. The molecular weight boundary between

C6 and C7. This value is used only when the option for constant

molecular weight interval (CONSTANT) has been selected. The

molecular weight boundaries of higher carbon numbers are calculated

by adding the corresponding molecular weight increment to this

value. For example, the molecular weight boundary between C7 and

C8 is calculated by adding the constant molecular weight interval (e.g.

12) to this number. (Default is 92)

■ Constant M.W. Interval. The constant molecular weight interval for

computing the extended analysis. This value is used only when the

option for constant molecular weight interval (CONSTANT) has been

selected. (Default is 12)

■ Variable M.W. Boundaries. A menu for specifying variable molecular

weight boundaries between carbon numbers, e.g., C7 to C8. These

numbers are used only if the option for variable molecular weight

interval (VARIABLE) has been selected.

■ Watson Characterization Factor. The average Watson characterization

factor for the entire heavy fraction. If a Watson factor is not entered, it

will be calculated so the computed specific gravity of the heavy

fraction will match the observed data. If a number is entered, it is used

to compute the specific gravity of all single carbon numbers without

any adjustment. Reasonable values are between the range of 10 to 13.

■ EOS Property Calc Method. Text label specifying the method of

calculating equation-of-state (EOS) parameters for critical

temperature, critical pressure, critical z-factor, and acentric factor for

single carbon numbers of extended fractions.

14 FSCN 6–×

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❑ CORRELATION. EOS parameters are calculated from correlations.

(Default)

❑ GENERALIZED. EOS parameters are obtained by table look-up

from the generalized property data bank.

■ EOS Property Data Source. Text label specifying whether the

calculated or experimental data of molecular weight, boiling point

temperature, and specific gravity, etc. are used to calculate EOS

parameters for single carbon numbers of extended fractions.

❑ SIMULATION. EOS parameters are computed using calculated

data of single carbon numbers. (Default)

❑ EXPERIMENT. EOS parameters are computed using experimental

data of single carbon numbers which are entered in the Distillation

Data Table.

■ Tc Correlation. Text label specifying a correlation option for

calculating critical temperature.

❑ RIAZI-DAUBERT. Riazi-Daubert correlation (Default)

❑ KESLER-LEE. Kesler-Lee correlation

❑ CAVETT. Cavett correlation

This selection is active only if the CORRELATION option has been

selected in EOS Property Calc Method.

■ Pc Correlation. Text label specifying a correlation option for

calculating critical pressure.



❑ CAVETT. Cavett correlation

This selection is active only if the CORRELATION option is


■ Zc Correlation. Text label specifying a correlation option for

calculating critical z-factor.


❑ RIEDEL-PITZER. Riedel-Pitzer correlation



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■ Acentric Factor Correlation. Text label specifying a correlation option

for calculating acentric factor.

❑ EDMISTER. Edmister correlation (Default)


❑ WHITSON. Whitson correlation



■ EOS Property Adjust Option. Text label specifying an adjustment

option for the calculated SCN equation-of-state parameters from

correlations.

❑ NO. All EOS parameters are calculated from correlations and no

further adjustment is needed. (Default)

❑ PC/ACENTRIC. Initial EOS parameters are calculated from

correlations. Critical pressure and acentric factor are adjusted so

the boiling point temperature and specific gravity calculated by

EOS match the values that have been used in correlations to

compute EOS parameters.

❑ VSH/ACENTRIC. Initial EOS parameters are calculated from

correlations. Acentric factor and volume shift parameter are

adjusted so the boiling point temperature and specific gravity

calculated by EOS match the values that have been used in

correlations to compute EOS parameters.

■ Distillation Data Table. Table used for entering experimental

distillation data. The measured data of molecular weight, mole (or

weight) fraction, specific gravity, and boiling point temperature in

degrees Fahrenheit for each single carbon number can be entered in

this table.

6.2.2 Calculate - Activate Calculation

The Calculate option in the Heavy menu is used to activate the calculation

procedure for heavy fraction characterization. Once the calculation task is

completed, the user may proceed to Graphics for reviewing the results of

the extended analysis.

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6.2.3 Graphics - Graphic Results of Extended Analysis

The Graphics option in the Heavy menu allows the user to review the

calculation results of the extended analysis in graphic mode. The plots for

the extended analysis include molecular weight, mole fraction, weight

fraction, specific gravity, boiling point temperature, critical temperature,

critical pressure, critical z-factor, acentric factor, volume shift parameter,

and binary interaction coefficients of methane and the extended fractions.

Refer to Section 9.2 for information on graphics operations.

6.2.4 Review - Tabular Results of Pseudo-Components

The equation-of-state parameters and mole fractions of the pseudoized

components of the extended fractions are displayed in tabular form using

Review. This table displays calculated results only, and any changes to this

table will not be stored in memory.

6.2.5 Save EOS - Save EOS Parameters

Save EOS allows the user to save equation-of-state parameters for the

pseudoized components of the extended fractions in a file. Refer to Section

9.10 for details of the Save EOS operation. It is required that the user must

activate heavy fraction calculation before selecting Save EOS.

6.2.6 Append EOS - Add Heavy Fraction Components to System

Append EOS allows the user to append the calculated EOS parameters of

the pseudoized components into the current fluid description. The heavy

fraction components will be merged into the current component pool. This

option can be selected only if the Calculate option has been activated.

6.2.7 Replace EOS - Load Heavy Fraction Components to System

Replace EOS allows the user to overwrite the current fluid description

with the calculated EOS parameters of the pseudoized heavy fraction

components. This option can be selected only if the Calculate option has

been activated.

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6.3 Pseudo - Pseudoization

Pseudoization is a calculation procedure used to combine and reduce

original fluid components to a pseudo system by specifying which of the

original components will be lumped into which pseudo-component. The

Pseudo function is used for performing this pseudoization procedure.

The pseudoization process is consistent with both the equation-of-state

and the viscosity correlation, in that the density and viscosity of the

original fluid system is preserved in the pseudo system. Experience has

shown that the saturation pressure of the pseudo-system may be slightly

in error. This can easily be adjusted through regression. The pseudoization

process, however, cannot be performed simultaneously with the

regression process.

In DESKTOP-PVT, pseudoization can be a stand-alone calculation, or it

can be performed in conjunction with laboratory procedures. The input

data are entered using the Pseudo Name and Parameter options,

regardless of the method used for running pseudoization. To run a stand-

alone pseudoization, the user must select Calculate from the Pseudo menu

after all data has been entered. If pseudoization is to be performed in

conjunction with laboratory procedures, the user should first select

Composition Sor from the Config menu to specify either unpseudoized or

pseudoized fluid system for laboratory procedures. The user then selects

Calculate from the Pseudo menu after all data has been entered.

DESKTOP-PVT will automatically load the pseudoized fluid composition

to those laboratory procedures chosen to use pseudo system. It is

recommended that all laboratory procedures are simulated with the same

fluid composition if the above mentioned procedure is followed.

Otherwise the user must enter the fluid composition directly. After

completing all test data entries, the user should select GO from the Run

menu.

6.3.1 Pseudo Name - Assign Pseudo-Components

Pseudo Name allows the user to enter the number and names of the

pseudoized components. This is required input for pseudoization, and no

defaults are provided. To add data click the AddRowBefore or

AddRowAfter button as many times as necessary to add the appropriate

number of rows needed. To delete a row, place the cursor in the row to be

deleted and click the DeleteRow button.

Since both the number and names of the pseudo-components are required

in the Parameter menu, they must be specified before entering other

pseudoization data. However, if a name is not given by the user, the

program will provide a default name for it automatically.

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6.3.2 Parameter - Input for Pseudoization

Parameter is used for entering data for pseudoization. The required data

include original fluid composition, temperature, saturation pressure and

assignments for lumping the original components into pseudo-

components. Figure 6-2 is an example of the Parameter Options Form.

Figure 6-2: Pseudoization Parameter Options Form

NOTE: To edit data indicated as <F5> on this form, either click MB1 over the

button next to the desired item or position the mouse cursor over the

box cell for the desired item to edit to make the F5 key accessible.

Any items that give you choice to make, move the mouse pointer

over the desired box cell and click MB3 to access a separate options

window. Choose the desired item and then click Ok to return to the

previous window.

■ Original Composition. The fluid composition in mole fraction of the

unpseudoized system. Only direct composition specification is

allowed. Refer to Section 7.2.1 for more information about composition

specification. This is required input.

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■ Temperature Unit. The temperature units used in the pseudoization

calculation. Refer to Section 7.2.3 for more information about

temperature units specification. This is required input. (Default is ˚F)

■ Temperature. The fluid temperature. This is required input.

■ Pressure Unit. The pressure units used in pseudoization calculation.

Refer to Section 7.2.4 for more information about pressure units

specifications. This is required input. (Default is PSIA)

■ Sat Pressure Type. Alpha label specifying the saturation pressure

type. This is required input.

❑ DEWPT. Dew point pressures

❑ BUBPT. Bubble point pressures (Default)

■ Saturation Pressure. The measured saturation pressure at the

specified temperature. This is required input.

■ Pseudo-Comp Pseudo-Name Lump. Panels for specifying which of

the original components will be lumped into a pseudo component.

There is a multiple item selection panel of this type for each pseudo-

component. The panels list the original components which have been

assigned to a pseudo-component and all original components which

have not been assigned to any pseudo-components. The original

components which have been assigned to a pseudo-component are

indicated by the square toggle button being turned on. This isrequired input.

6.3.3 Calculate - Activate Calculation

The Calculate option in the Pseudo menu is used to activate the

calculation procedure for pseudoization. No input data is required. Once

the calculation task is completed, the user may select Review for

examining the pseudoization results.

6.3.4 Review - Tabular Results of Pseudoization

The equation-of-state parameters and mole fractions of the pseudoized

components are displayed in tabular form using Review. This table is only

used for examining the calculated results. Any changes to this table will

not be stored in memory.

6.3.5 Save EOS - Save EOS Parameters

Save EOS allows the user to save equation-of-state parameters for the

pseudoized components in a file. Refer to Section 9.10 for details of the

Save EOS operation. It is required that the user must activate calculation

before selecting Save EOS.

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6.3.6 Replace EOS - Load Pseudo Components To System

Replace EOS allows the user to overwrite the current fluid description

with the EOS parameters of the pseudoized components. This option can

be selected only if the Calculate option has been activated.

6.3.7 Append EOS - Add Pseudo Components To System

Append EOS allows the user to append EOS parameters of the

pseudoized components to the current fluid description. The pseudo

components will be merged into the current component pool. This option

can be selected only if the Calculate option has been activated.

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6.4 Regres - Automatic Parameter Adjustment

The Regres menu on the Menu Bar is used for entering parameters for the

nonlinear regression calculation. The Regres menu is active only if the

Regression option in the Config menu has been selected.

There are three options available in the Regress menu, Variable, Limits,

and Control. Variable is used for specifying the equation-of-state

parameters to be adjusted during nonlinear regression. Limits allows the

user to specify the lower and upper bounds of the regression parameters.

Control is used for specifying calculation tolerance and output quantity.

6.4.1 Variable - Regression Parameters

The parameters for each component that will be adjusted during

regression are marked as positive integers in these menus. The number 0

indicates the parameters will not be changed during regression. The

positive integers will be referred to as regression variables. A regression

variable, e.g. 1, can be assigned to any location in any of these menus,

provided it indicates the regressed parameter. A single variable can be

used to modify the same property of multiple components. The various

components using the same regression variable should be closely related,

such as heavy fractions. For example, regression variable 1 can be

assigned to all binary interaction coefficients of methane and heavy

fractions.

The total number of regression variables is computed as the maximum

integer given in these menus. If only a regression variable of 3 is entered,

the program will try to perform the regression calculation starting with

three regression variables even through regression variables 1 and 2 are

not assigned to any parameters. It is suggested that contiguous integers

starting from one are used to assign regression variables.

Adjusting too many parameters simultaneously is likely to create an ill-

conditioned problem. Physically meaningless values for some parameters

may be generated as a result. Therefore, it is desirable to limit the number

of variables.

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The parameters available for regression are categorized into ten types as

shown in Figure 6-3.

Figure 6-3: Regression Variable Panel

These are:

■ EOS Property. Equation-of-state parameters of molecular weight,

critical temperature, pressure and z-factor, acentric factor, omega A,

omega B, and parachor (Figure 6-4). If a three-parameter EOS is

selected, this table will include volume shift parameter.

Figure 6-4: EOS Regression Variable Definition Table

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■ Binary Coeff. Component binary interaction coefficients (Figure 6-5).

Figure 6-5: Binary Coeff Regression Variable Definition Table

■ Composition. Component composition in mole fraction. This option

can be used only if fluid compositions in all laboratory procedures are

the same. A maximum of Nc-1 components may be regressed, where

Nc is the number of fluid components. A regression variable of 99

must be assigned to a component composition used to preserve the

mole fraction constraint (Figure 6-6).

Figure 6-6: Composition Regression Variable Definition Table

■ Volume Shift. The D and E parameters of the correlation for

calculating volume shift parameters. This menu is available only if a

three-parameter EOS has been specified.

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■ H2O Binary. Binary interaction coefficients for water (H2O) and all

other components. This menu is available only if Thermal in the

Config menu has been activated, and the H2O component has not

been assigned as a fluid component.

■ LBC Visc. The Lohrenz-Bray-Clark viscosity coefficients.

Figure 6-7: k-Coefficient of Lohrenz-Bray-Clark Viscosity Correlation

■ VISP k-Coef. The k-coefficients (k1 to k7) for calculating the viscosity

of the reference component in the Pedersen et al. viscosity correlation

(Figure 6-8).

Figure 6-8: k-Coefficient of Pedersen Viscosity Correlation

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■ VISP Tc-Binary. The binary interaction coefficient for calculating

mixture pseudo-critical temperature used in the Pedersen et al.

viscosity correlation (Figure 6-9).

Figure 6-9: Tc-Binary Interaction Coefficient of Pederson Viscosity Correlation

■ K-Value Correl. The component coefficients of K-value correlation.

The correlation is expressed as

(6-1)

where Ai to Ei are constant coefficients for component i, P is pressure

in psia and T is temperature in Rankin (Figure 6-10).

Figure 6-10: Component Coefficients of K-Value Correlation

Ki Ai

Bi

P----- Ci+ + P⋅ EXP

Di–

T Ei–---------------

⋅=

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■ CO2TAB Correl. The correlations for calculating properties of carbon

dioxide saturated water are given in Section 5.2.7.

Figure 6-11 shows the main data entry menu for assigning regression

variables to correlation coefficients of carbon dioxide saturated water

properties. The selection items are for the correlation of carbon dioxide

solubility in pure water, the correlation to adjust the effects of salinity

on carbon dioxide solubility in water, and the correlation to calculate

density of carbon dioxide saturated water. The density correlation is

used in computing water formation volume factor.

Figure 6-11: Correlation Coefficients of Carbon Dioxide Saturated WaterProperties

Figure 6-12 shows the data entry table for assigning regression

variables to correlation coefficients of solubility of carbon dioxide in

pure water. The coefficients are a0 to a4, b0 to b4, and c0 to c4 give in

Section 5.2.7.

Figure 6-12: Correlation Coefficients of Solubility of Carbon Dioxide in PureWater

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variables to s0 and s1 coefficients for adjusting the salinity effects on

the carbon dioxide solubility in water.

Figure 6-13: Assigning Regression Variables to s0 and s1 Coefficients


variable to coefficient d1 for calculating carbon dioxide saturated

water density.

Figure 6-14: Assigning Regression Variable to Coefficient d1

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6.4.2 Limits - Upper and Lower Bounds

The Limits option is used to set the initial value of each regression variable

and establish upper and lower bounds for each variable (Figure 6-15). The

Initial column in the Limits menu is used for entering the initial values of

regression variables. The Minimum and Maximum columns are used for

entering the lower and upper bounds of regression variables. The default

values for initial, minimum, and maximum are 1, 0.8, and 1.2, respectively.

The initial value is normally 1 for the first regression attempt. If additional

runs are made, the last set of values from a previous run may be used.

Figure 6-15: Regression Limits Panel

Regression variables are used to alter the initial values of various EOS

properties. Most of the EOS properties are adjusted by multiplying their

initial values with regression variables. The exceptions are binary

interaction coefficients, composition and volume shift parameters, where

subtraction is used instead of multiplication. For this treatment of

regression variables, using values equal to 1 for all regression variables is

equivalent to using the unaltered EOS properties.

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6.4.3 Control - Calculation and Output Control

The Control option contains data for controlling the nonlinear regression

process. In most cases the default values should be used, omitting any

modifications in the Control menu. Figure 6-16 is an example of the menu.

Figure 6-16: Regression Control Panel

■ Max Number of Iterations. The maximum number of iterations

allowed in regression. This is required input. (Default is 5)

■ Print-Out Control. Alpha label specifying the quantity of output for

regression. This is required input.

❑ Basic. Only the values of the objective function and the regression

variables at each regression iteration are printed.

❑ Intermediate. In addition to the Basic output, a table of calculated

and observed values is printed. (Default)

❑ Detail. Adds details of the internal regression calculation to the

output.

■ Initial Search Vector Length. The initial value of the search vector

length in the regression calculation. This is required input. (Default is

0.2)

■ Minimum Length of Search Vector. A tolerance used as convergence

criterion. The required length of a search vector must be greater than

this number. This is required data. (Default is 0.001)

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■ Increment For Derivative Calculation. Increment used to perturb

variables to compute numerical derivatives. This is required input.(Default is 0.001)

■ Required Reduction in Sum-of-Square. A tolerance used as a

convergence criterion. The required reduction in the sum-of-square

from one iteration to the next must be greater than this number. This isrequired input. (Default is 0.01)

■ Regression Use Non-Volumetric Data Only. Alpha label specifying if

only non-volumetric data are to be used in the regression.

❑ YES. Only non-volumetric observed data are used in the

regression.

❑ NO. All observed data are used in the regression. (Default)

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Chapter

7

Input Data for Laboratory Procedures

7.1 Introduction

The Tests menu on the Menu Bar is used for entering data from laboratory

measurements. The Tests menu has a dynamic arrangement so only the

tests selected in the Test Type selection window in the Config menu will be

highlighted. The user must enter all required data for all selected tests, but

may enter data in any sequence.

The user can request the data entry menu for a test by clicking on the

desired item with MB1. If the test has multiple runs, an additional menu

containing run numbers will be displayed. The user must select a run

before the data entry menu can be accessed.

In Section 7.2, commonly used data for laboratory procedures are

described. The data set for each laboratory procedure is discussed in

Section 7.3.

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Input Data for Laboratory Procedures DESKTOP-PVT USER’S GUIDE

7.2 Common Input Data

In this section, the input data used by most of the laboratory procedures

are discussed. An example of these data is the fluid composition required

for all laboratory procedures. Not all of the data discussed here are

required input. They can be optional or required. Some of the required

data have been given default values in the program.

7.2.1 Composition

The fluid composition is required for most of the laboratory test

procedures. As discussed in Section 4.11, there are two ways to specify the

fluid composition in DESKTOP-PVT. The fluid composition for a test can

be entered directly, or the liquid, vapor, or overall composition of an

intermediate step in another test can be loaded. The latter method is

referred to as an indirect composition specification. For direct composition

specification, the user must enter the numerical values of the fluid

composition in mole fraction. For indirect composition specification, the

user must specify the referenced test and its particular step. Both

specifications are completed through the Composition item in the data

entry menus for laboratory procedures.

For all tests, there is a Composition entry field. To access the composition

entry menu, the user should position the cursor on the field, and press the

F5 function key or click the field with MB1.

For direct composition specification, the entry menu has a two-column

format for most of the tests. The first column, which is not used for data

entry, lists the component names under the Component header. The

second column, under the Mole Fraction header, is used for entering fluid

composition in mole fraction. There are a few tests, for example swelling

and multiple contact vaporization tests, which require specification of

both the fluid and the injected gas compositions. A three-column

composition menu is provided for these tests. The fluid composition is

entered in the second column with the Fluid Mixture header, and the third

column, with the Injected Gas header, is used for entering the injected gas

composition.

In a composition entry menu, the F2 function key can be used to copy a

previously entered fluid composition of other laboratory test procedures.

A menu of abbreviated test names will be displayed once the user presses

the F2 function key. By clicking the button next to the desired test and then

click the Ok button, the program is instructed to copy the fluid

composition from that test. This copy composition function can save data

entry efforts for simulating several tests with the same fluid composition.

For indirect composition specification, the composition assignment is a

two-step procedure. A menu of abbreviated test names will be displayed

when the user presses the F5 function key in the Composition entry field

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DESKTOP-PVT USER’S GUIDE Input Data for Laboratory Procedures

or clicking the Composition entry field with MB1. The user must select a

test which references one of its liquid, vapor, or overall compositions.

The user must provide the run sequence of all laboratory procedures if the

test compositions are to be indirectly specified. In the Run Sequence menu

the user also specifies which tests will use indirect composition

specification. DESKTOP-PVT will process the user specifications in the

Run Sequence menu, and list the tests that can be referenced. The tests

menu lists a subset of all the laboratory tests specified in the Test Type

selection window of the Config menu.

A second menu will be displayed once the user has selected a test in the

abbreviated test names menu. This menu lists the pressure stages for the

selected test. The user should position the cursor on the desired pressure

stage and press Enter to complete the indirect composition specification.

7.2.2 Laboratory Conditions

In addition to the fluid compositions, the user must specify other

conditions for laboratory procedures. The user has to specify either the

system temperature or pressure which is kept constant through the entire

simulation. The user should then specify the pressure stages if the system

temperature is fixed (if the system pressure is fixed, the temperature

stages must be specified). In the menus for entering laboratory

measurements, to create additional data entry columns or rows for

pressure (or temperature) stages click either the AddRowBefore or

AddRowAfter button. To delete data entry columns or rows, click the

DeleteRow button. When the user is finished adding or deleting data, click

Ok to exit a data entry menu.

7.2.3 Temperature Units

The temperature units are required input for most laboratory procedures.

Default units are provided in the program. There are four temperature

units in DESKTOP-PVT:

■ F. Degrees Fahrenheit

■ C. Degrees Centigrade

■ K. Degrees Kelvin

■ R. Degrees Rankin

To change the temperature units, the user can either enter one of the unit

identifiers (F, C, K or R) directly, or select the temperature units menu by

clicking MB3 in the temperature units specification field. A selection menu

will be displayed. Select the desired item by the diamond button next the

that item and then click Ok to return to the previous menu.

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7.2.4 Pressure Units

The pressure units are required input for most laboratory procedures.

Default units are provided in the program. There are four pressure units in

DESKTOP-PVT:

■ PSIA. Pounds per square inch, absolute

■ PSIG. Pounds per square inch, Gauge

■ KPA. Kilo-Pascals

■ KGCM2. Kilo-grams per square centimeter

To change the pressure units, the user can either enter one of the unit

identifiers (PSIA, PSIG, KPA or KGCM2) directly, or select the pressure

units menu by click MB3 in the pressure units specification field. A

selection menu will be displayed. Select the desired item by the diamond

button next the that item and then click OK to return to the previous

menu.

7.2.5 Density Units

The density units are required input for certain laboratory procedures.

Default units are provided in the program. There are two density units in

DESKTOP-PVT:

■ LB/FT3. Pound Mass per cubic foot

■ GM/CC. Gram per cubic centimeter

To change the density units, the user can either enter one of the unit

identifiers (LB/FT3 or GM/CC) directly, or select the density units menu

by clicking MB3 in the density units specification field. A selection menu

will be displayed. Select the desired item by the diamond button next the

that item and then click OK to return to the previous menu.

7.2.6 Gas-Oil Ratio Units

The gas-oil ratio (GOR) units are required input for certain laboratory

procedures. Default units are provided in the program. Two units options

are available:

■ SCM/STCM. Metric units of standard cubic meter of gas per cubic

meter of stock tank oil

■ SCF/STB. Field units of standard cubic feet of gas per barrel of stock

tank oil

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To change the GOR units, the user can either enter one of the unit

identifiers (SCM/STCM or SCF/STB) directly, or select the GOR units

menu by clicking MB3 in the GOR units specification field. A selection

menu will be displayed. Select the desired item by the diamond button

next the that item and then click OK to return to the previous menu.

7.2.7 Enthalpy Units

The enthalpy units are required input for some laboratory procedures.

Default units are provided in the program. Options are:

■ KBTU/LBMOLE. Kilo-btu per pound-mole

■ J/KGMOLE. Joule per kilogram-mole

To change the enthalpy units, the user can either enter one of the unit

identifiers (KBTU/LBMOLE or J/KGMOLE) directly, or select the

enthalpy units menu by clicking MB3 in the enthalpy units specification

field. A selection menu will be displayed. Select the desired item by the

diamond button next the that item and then click OK to return to the

previous menu.

7.2.8 Saturation Pressure Type

For certain tests, the saturation pressure type is required input. This input

is an alpha label for one of two options:

■ DEWPT. Dewpoint pressures

■ BUBPT. Bubblepoint pressures

To change the saturation pressure type, the user can either enter one of the

unit identifiers (DEWPT or BUBPT) directly, or select the saturation

pressure type menu by clicking MB3 in the saturation pressure type

specification field. A selection menu will be displayed. Select the desired

item by the diamond button next the that item and then click Ok to return

to the previous menu.

7.2.9 Weight Factors

There is a corresponding weight factor entry for each observed data. The

weight factors are used in the nonlinear regression process so the user can

control the quality of the match between observed data and simulated

phase behavior. Unless otherwise stated, the weight factor for saturation

pressure is 10, and the default weight factor is 1 for other measured

quantities.

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7.3 Input Data for Laboratory Procedures

The input requirements for all laboratory procedures are discussed in

detail in this section. The Tests menu only highlights the tests which have

been selected in the Test Type selection window in the Config menu. In the

following sections, for each test there is a short description with an

example of the corresponding menu. Also included is a list of all options

for the specified test menu, with a definition for each option. There are a

total of twenty-three test to choose from, where are:

■ Gas Z-Factor

■ Liquid Density

■ Vapor Pressure

■ Saturation Pressure

■ Viscosity

■ Constant Composition Expansion

■ Constant Volume Depletion

■ Swelling

■ Differential Expansion

■ Multi-Contact Vaporization

■ Phase Envelope/Psat

■ Gas Enthalpy

■ Liquid Enthalpy

■ Water Property

■ Saturating Pressure/H2O

■ Distillation

■ Steam Distillation

■ Separator/No Reg

■ Separator/Reg

■ Phase Envelope/Full

■ Composition Variations with Depth

■ Properties of Carbon Dioxide Saturated Water

■ Multiple Contact Steam Vaporization

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7.3.1 Z-Factor: Gas Compressibility Factor

The gas compressibility factor (Z-FACTOR) of a gas mixture is calculated

as a function of pressure and temperature. Figure 7-1 shows the input

menu for calculating the compressibility factor of gas mixtures.

Figure 7-1: Gas Z-Factor Menu

■ Composition. The composition of the gas mixture in mole fraction.

This is required input.

■ Temperature Unit. The temperature units which are the same for all

temperature measurements in this test. This is required input.(Default is ˚F)

■ Temperature. The temperature at which all data are measured in this

test. This is required input.

■ Pressure Unit. The pressure units which are the same for all pressure

measurements in this test. This is required input. (Default is PSIG)

■ Density Unit. The density units which are the same for all density

measurements in this test. This is required input. (Default is LB/FT3)

■ Lab Measurements (Lab Data). Pressing the F5 function key or

clicking MB1 will display the table for entering laboratory measured

data, i.e., pressure, density, z-factor and viscosity. The detailed table

entries are discussed later.

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■ Weight Factor/Lab Data. The regression weight factors of the

measured data. (Default is 1)

Figure 7-2 shows an example of the table for entering laboratory measured

data. In this example the gas z-factors are measured at two pressure

stages.

Figure 7-2: Data Entry Table for Gas Z-Factor

■ Pressure. The pressure stages at which data were measured. This isrequired input.

■ Gas Dens. The gas densities measured at the pressure stages.

■ Z-Factor. The gas z-factors measured at the pressure stages.

■ Gas Visc. The gas viscosities (cp) measured at the pressure stages.

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7.3.2 Density: Liquid Density

The liquid density of a liquid mixture (LIQDEN) is calculated as a

function of pressure and temperature. Figure 7-3 shows the input menu

for calculating the density of liquid mixtures.

Figure 7-3: Liquid Density Menu

■ Composition. The composition of the liquid mixture in mole fraction.










■ Lab Measurements (Lab Data). The laboratory measured data

including pressure, density, z-factor and viscosity. The detailed table




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data. Liquid densities are measured at two pressure stages in this

example.

Figure 7-4: Data Entry Table for Liquid Density


■ Liq Dens. The liquid densities measured at the pressure stages.

■ Z-Factor. The liquid z-factors measured at the pressure stages.

■ Liq Visc. The liquid viscosities (cp) measured at the pressure stages.

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7.3.3 Vapor Pressure: Pure Component Vapor Pressure

The vapor pressure of a pure component (VP) is calculated as a function of

temperature in this test. Figure 7-5 shows the input menu.

Figure 7-5: Vapor Pressure

■ Composition. The fluid composition in mole fraction. The fluid can

consist of multiple components, but only one component can have a

nonzero value for mole fraction. This is required input.








including temperature, vapor pressure, density, and z-factor. The

detailed table entries are discussed later.


measured data. The default weight factors are 10 for vapor pressures,

and 5 for both densities and z-factors.

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Figure 7-6 shows an example of the table for entering vapor pressure data.

The vapor pressures are measured at two temperature stages in this

example.

Figure 7-6: Data Entry Table for Vapor Pressure

■ Temp. The temperatures at which vapor pressures are measured in

this test. This is required input.

■ Vapor Pres. The measured vapor pressures at the temperature stages.


■ Density. The saturated fluid densities measured at the stage

temperatures and vapor pressures.

■ Z-Factor. The saturated fluid z-factors measured at the stage

temperatures and vapor pressures.

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7.3.4 Sat Pressure: Mixture Dew/Bubblepoint Pressure

The dewpoint, or bubblepoint, pressure of a mixture (PSAT) is calculated

as a function of temperature in this test. Figure 7-7 shows the input menu.

Figure 7-7: Saturation Pressure Menu

■ Composition. The composition of the fluid mixture in mole fraction.




■ Saturation Pressure Type. Alpha label specifying the type of the

measured saturation pressures. This is required input. (Default is

BUBPT)






including temperature, saturation pressure, density, and z-factor. The


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measured data. The default weight factors are 10 for saturation

pressures, and 5 for both densities and z-factors.


data. The saturation pressures are measured at one temperature stage in

this example.

Figure 7-8: Data Entry Table for Saturation Pressure

■ Temp. The temperatures at which saturation pressures are measured

in this test. This is required input.

■ Dewpoint or Bubble Pt. The measured saturation pressures at the

temperature stages. A realistic value should be entered, even if no data

is available, since it will be used as the starting value for the saturation

pressure calculation. A poor estimate can result in convergence failure.



temperatures and saturation pressures.


temperatures and saturation pressures.

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7.3.5 Viscosity: Liquid/Vapor Viscosity

The viscosity of a fluid mixture (VISC) is calculated as a function of

pressure and temperature. Figure 7-9 shows the input menu for

calculating the viscosity of fluid mixtures.

Figure 7-9: Viscosity Menu

■ Fluid Type. Alpha label specifying the fluid mixture type. This isrequired input.

❑ LIQUID. The fluid is liquid. (Default)

❑ VAPOR. The fluid is vapor.









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including pressure, density, z-factor and viscosity. The detailed table




Figure 7-10 shows an example of the table for entering laboratory

measured data. The viscosities are measured at two pressure stages in this

example.

Figure 7-10: Data Entry Table for Viscosity


■ Density. The densities measured at the pressure stages.

■ Z-Factor. The z-factors measured at the pressure stages.

■ Viscosity. The viscosities measured at the pressure stages.

7.3.6 Cnst Composition: Constant Composition Expansion

This test may also be called flash vaporization, flash liberation, pressure-

volume relations, or flash expansion.

The constant composition expansion (CCEXP) procedure begins with a

fluid sample at a pressure above its saturation pressure. Pressure is

reduced in a sequence of discrete steps until the saturation pressure is

reached. After each pressure reduction, the volume is measured and

normalized relative to the volume at the saturation pressure.

Pressure is reduced below the saturation pressure in a further sequence of

discrete steps. After each pressure reduction the vapor-liquid mixture is

equilibrated. The total volume of the mixture is normalized relative to the

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volume at the saturation pressure. Sometimes the volume fraction of

liquid is measured. The CCEXP procedure is performed at a constant

temperature. Figure 7-11 shows the input menu for simulating the CCEXP

procedure.

Figure 7-11: Constant Composition





■ Temperature. The cell temperature at which all data are measured in


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■ Saturation Pressure Type. Alpha label specifying the type of


BUBPT)



■ Saturation Pressure (Psat). The measured saturation pressure at the

cell temperature. This is required input.

■ Weight Factor/Psat. The regression weight factor of the measured

saturation pressure. (Default is 10)

■ Z-factor@ Psat (Z-Psat). The measured fluid compressibility factor (Z-

factor) at the cell temperature and saturation pressure.

■ Weight Factor/Z-Psat. The regression weight factor of the measured Z-

factor at the cell temperature and saturation pressure. (Default is 1)

■ Liq Volume Fraction Type. Two options are available to define the

reference volume used for normalizing measured liquid volumes. This

data is used to select the reference volume and define the volume

fraction of liquid. Volume fraction of liquid is defined as the liquid

volume measured at a pressure stage divided by the reference volume.


❑ MEAS PRES. The reference volume is the total cell volume at the

pressure stage at which the liquid volume is measured.

❑ SATURATION. The reference volume is the total cell volume at the

saturation pressure. (Default)

■ Lab Measurements (Lab Data). The laboratory measured data include

pressure, total cell volume, volume fraction of liquid, gas z-factor, oil

z-factor, oil viscosity, gas viscosity, oil density, and gas density. The



laboratory measured data. (Default is 1)

■ Oil Compositions (OComp). The oil phase compositions in mole

fraction at the pressure stages.

■ Weight Factor/OComp. The regression weight factors of the measured

oil phase compositions. (Default is 1)

■ Gas Compositions (GComp). The gas phase compositions in mole


■ Weight Factor/GComp. The regression weight factors of the measured

gas phase compositions. (Default is 1)

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measured CCEXP data.

Figure 7-12: Data Entry Table for Constant Composition Expansion


■ Relative Vol. The total volume of the fluid mixture measured at the

pressure stages divided by the volume measured at the saturation

pressure.

■ LVol Frac. The measured volume fraction of liquid at the pressure

stages. See Liq Volume Fraction Type above for the definition of

volume fraction of liquid.

■ Gas Z-Fac. The gas z-factors measured at the pressure stages.

■ Oil Z-Fac. The oil z-factors measured at the pressure stages.

■ VISCo. The oil viscosities measured at the pressure stages, in

centipoise.

■ VISCg. The gas viscosities measured at the pressure stages, in

centipoise.

■ DENo. The oil densities measured at the pressure stages, in gm/cc.

■ DENg. The gas densities measured at the pressure stages, in gm/cc.

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7.3.7 Cnst Volume: Constant Volume Depletion

The constant volume depletion (CVDEP) procedure begins with a fluid

sample, usually a condensate, at its saturation pressure and temperature

of interest. The pressure is then reduced in a series of discrete steps

allowing the fluid to expand. After each expansion, the PVT cell is

equilibrated and returned to its original volume by withdrawing vapor at

a constant pressure.

Data measured and reported at each pressure level includes the

composition of the produced gas, the molecular weight of the heavy

fraction (C7+) of the produced gas, the gas z-factor, the cumulative

production of gas as a fraction of the original gas in the PVT cell, and the

fraction of the cell volume occupied by the liquid after returning to the

original volume. Figure 7-13 shows the input menu for simulating the

CVDEP procedure.

Figure 7-13: Constant Volume Depletion Menu



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measurements in this test. This is required input. (Default is ˚F)





BUBPT)



■ Saturation Pressure (Psat). The measured saturation pressure at the

cell temperature. This is required input.

■ Weight Factor/Psat. The regression weight factor of the measured


■ Z-factor @ Psat (Z-Psat). The measured fluid compressibility factor (Z-

factor) at the cell temperature and saturation pressure.

■ Weight Factor/Z-Psat. The regression weight factor of the measured Z-

factor at the cell temperature and saturation pressure. (Default is 1)

■ First Heavy Component Name. The component name of the lowest

molecular weight component in the heavy fraction for which

molecular weight is being reported. Typically the molecular weight of

the C7+ fraction is reported.

■ Last Heavy Component Name. The component name of the highest

molecular weight component in the heavy fraction for which

molecular weight is being reported.


including pressure, the molecular weight of the heavy fraction of the

produced gas, gas z-factor, oil z-factor, cumulative gas produced,

volume fraction of oil, oil viscosity, gas viscosity, and oil density. The







oil phase compositions (Default is 1)

■ Gas Compositions (GComp). The produced gas phase compositions

in mole fraction at the pressure stages.

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gas phase compositions (Default is 1)

■ Black Oil Table Generation. The dialog window for generating black

oil table data.


measured CVDEP data.

Figure 7-14: Data Entry Table for Constant Volume Depletion


■ Gas M.W.+. The molecular weight of the heavy fraction of the

produced gas.

■ Gas Z-Fac. The produced gas z-factors measured at the pressure

stages.


■ Cum Gas Prod. The cumulative gas produced after returning the PVT

cell to its original volume at the pressure stages. This is expressed as a

mole fraction of the gas originally in the PVT cell.

■ Oil Vol Frac. The measured volume fractions of oil after returning the

PVT cell to its original volume at the pressure stages.


centipoise.

■ VISCg. The viscosities of the produced gas measured at the pressure

stages, in centipoise.


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Figure 7-15 shows the dialog window used to enter black oil table

generation parameters.

Figure 7-15: Black Oil Table Generation Parameters

■ Algorithm. The user may select between NONE or WHITSON or

COATS for the method used to generate the black oil data table. If the

NONE option is selected, no table is generated. The WHITSON option

generates the black oil table by the algorithm described by Whitson

and Torp 10. The COATS option generates the black oil table by the

algorithm described by Coats11.

■ Separator Conditions. The separator conditions used to generate the

black oil data. An example is shown in Figure 7-16. Multi-stage

separator conditions are specified in the same manner as other

separator tests. For a full description, of the data fields, see the input

description of the Separator tests.

Figure 7-16: Separator Definition for Black Oil Table Generation.

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■ Saturated Pressure Table. A table of saturated pressure data is

automatically generated from the laboratory data. However, the user

may manually define the pressure levels at which saturated data is

generated. The dialog window is shown in Figure 7-17. The program

will ignore pressures above the saturation pressure of the initial

composition. It will extrapolate to pressures above the initial

saturation pressure by adding equilibrium gas to the initial

composition.

Figure 7-17: Saturation Pressures at which black oil data is generated.

■ Delta Pressure Table. The pressure levels above saturation pressure at

which undersaturated data is calculated. An example is shown in

Figure 7-18.

Figure 7-18: Pressure levels above the saturation pressure at which black oildata is generated.

■ Output Units. A choice can be made between FIELD or METRIC or

LAB units for output.

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■ Viscosity. The user can choose to output either experimental data,

where available, or computationally generated viscosity data.

Viscosity data is often more difficult to match than volumetric data, so

the user may wish to retain his original experimental viscosity values

when they are available.

7.3.8 Swelling: Swelling Test

The swelling test (SWELL) begins with a fluid sample, usually a liquid, at

its saturation pressure and temperature of interest. A lean vapor is injected

into the fluid sample in a series of discrete stages, causing an elevation of

saturation pressure. For a liquid sample, the fluid may switch from a

bubblepoint to a dewpoint between two stages thereby spanning a critical

mixture.

Data measured and reported at the end of each stage includes the

saturation pressure of the new mixture, the type of saturation pressure

(dewpoint or bubblepoint), and the volume of the saturated mixture

relative to the saturated volume of the original sample. Figure 7-19 shows

the input menu for simulating the SWELL procedure.

Figure 7-19: Swelling Test Menu

■ Composition. The composition of the fluid mixture and injected gas in

mole fraction. This is required input.



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including moles of injected gas, volume of the new saturated mixture,

saturation pressure, and the type of saturation pressure. The detailed

table entries are discussed later.


laboratory measured data. The default weight factors are 1.5 for the

saturation pressures, and 1 for the volumes of the saturated mixtures.


measured SWELL data.

Figure 7-20: Data Entry Table for Swelling Test

■ Inj Gas Frac. Moles of injected gas in the mixture divided by the total

number of moles in the mixture at the end of any stage. This isrequired input.

■ Sat Vol Frac. The volume of the saturated mixture at the end of any

stage divided by the saturated volume of the original mixture.

■ Sat Pressure. The measured saturation pressure of the mixture at the

end of any stage.

■ Sat Pres Type. Alpha label specifying the type of measured saturation

pressures. This is required input.

❑ DEWPT. Dewpoint pressures

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❑ BUBPT. Bubblepoint pressures (Default)

7.3.9 Differential: Differential Expansion

The differential expansion experiment, also called differential liberation or

differential vaporization, is normally performed on black oils. The

differential expansion (DIFF) procedure begins with an oil sample at its

saturation pressure and temperature of interest. The pressure is reduced in

a series of discrete steps allowing the fluid to expand. After each

expansion, the PVT cell is allowed to equilibrate and all evolved gas is

removed from the cell at the constant pressure.

Data measured and reported at each pressure level includes the solution

gas-oil ratio, relative oil volume, oil density, z-factor of the withdrawn gas,

and gravity of the withdrawn gas.

Figure 7-21 shows the input menu for simulating the DIFF procedure.

Figure 7-21: Differential Expansion Menu



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measurements in this test. This is required input. (Default is PSIA)

■ Bubblepoint Pressure (BUBPT). The measured bubblepoint pressure

at the cell temperature. This is required input.

■ Weight Factor/BUBPT. The regression weight factor of the measured

bubblepoint pressure. (Default is 10)

■ Standard Temperature. Standard temperature. (Default is 60)

■ Standard Pressure. Standard pressure. (Default is 14.7)

■ Gas-Oil Ratio (GOR) Unit. The units for all gas-oil ratio

measurements. This is required input. (Default is SCF/STB)

■ GOR Calculation Option. Alpha label specifying the definition of gas-

oil ratio. This is required input.

❑ EVOLVED. Cumulative standard volume of gas evolved at a

pressure level per volume of residual oil at standard temperature

and pressure.

❑ SOLUTION. Standard volume of gas still in the oil at a pressure

level per volume of residual oil at standard temperature and

pressure. (Default)


including pressure, relative oil volume, gas-oil ratio, gas z-factor, oil

viscosity, gas viscosity, oil density, and gas gravity. The detailed table




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measured DIFF data.

Figure 7-22: Data Entry Table for Differential Expansion


■ Rel Oil Vol. The relative oil volumes (oil formation volume factor, Bo),

barrels of oil at a pressure level per barrel of residual oil at 60 ˚F.

■ GOR. The gas-oil ratio at a pressure level. See GOR Calculation

Option above for the definition of gas-oil ratio.

■ Gas Z-Fac. The z-factors of the produced gas measured at the pressure

stages.


centipoise.

■ VISCg. The viscosities of the produced gas measured at the pressure

stages, in centipoise.


■ Gas Gravity. The produced gas gravity at the pressure stages.

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7.3.10 Multi-Contact: Multiple Contact Vaporization

The multiple contact vaporization (MCVAP) procedure begins with an oil

sample at a given pressure and temperature. The MCVAP test can perform

either a gas-cycling process or an oil-cycling process. In a gas-cycling

process, gas will be injected into oil in a series of steps at constant

pressure. By default this process is differential, i.e., all gas is removed at

the end of each contact step. The user can decide not to remove any gas by

specifying the process as constant composition. In an oil-cycling process,

after an initial contact of injected gas with oil, the remaining oil is removed

from the cell. For subsequent steps, the original oil is added to the gas

phase remaining from the previous step.

Data measured and reported at each contact step includes moles of gas (or

oil) removed, gas (or oil) z-factor, and liquid volume fraction. In addition,

the program can construct a pseudo-ternary diagram if the user defines

three pseudo-components (light, intermediate and heavy).

Figure 7-23 shows the input menu for simulating the MCVAP procedure.

Figure 7-23: Multiple Contact Vaporization Menu

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■ Composition. The composition of the fluid mixture and injected gas in


■ Type of Cycling Process. Alpha label specifying the type of cycling

process, This is required input.

❑ GAS. Gas cycling process (Default)

❑ OIL. Oil cycling process

■ Constant Composition Process. Alpha label specifying the type of

MCVAP test. This is required input.

❑ YES. Constant composition MCVAP test

❑ NO. Differential MCVAP test (Default)







■ Bubblepoint Pressure (BUBPT). The measured bubblepoint pressure

at the cell temperature. This is required input.

■ Weight Factor/BUBPT. The regression weight factor of the measured


■ Test Operating Pressure. The operating pressure of the multiple

contact vaporization test. This is required input.

■ Pseudo Component Assignment. Define three pseudo-components

by specifying which original components will be lumped into which

pseudo component. The pseudo-ternary is constructed only if pseudo-

components are defined. The process of defining pseudo-components

is identical to the pseudoization function discussed in Chapter 6.


including moles of fluid (gas or oil) added, moles of fluid (gas or oil)

removed, gas z-factor, and liquid volume fraction. The detailed table




R2003.0 - Landmark 7-103



measured MCVAP data.

Figure 7-24: Data Entry Table for Multiple Contact Vaporization

■ Moles Added. The number of moles of fluid (gas or oil) added at each

contact step. It is assumed the oil originally in the PVT cell is one mole.


■ Moles Removed. The number of moles of fluid (gas or oil) removed

after equilibration at each contact step.

■ Gas Z-Factor. The z-factors of the removed gas at each contact step.

■ Liq Vol Frac. The liquid volume fraction before gas removed at each

contact step.

7.3.11 Phas Envlop/Psat: Dew/Bubblepoint Phase Envelope

The phase envelope calculation (ENVELOPE) consists of a series of

bubblepoint and dewpoint calculations delineating the boundary of the

two-phase region. The calculation may be performed for both oil and gas

fluid systems.

Convergence of the saturation pressure calculations using an equation of

state is dependent upon the starting pressure at a given temperature. As a

result, data which define starting values for pressure and temperature

must be specified. These starting values are defined by specifying a range

of pressures and temperatures for both the upper and lower portions of

the phase envelope. The program will perform a saturation pressure

calculation for each temperature specified in this range. The program will

continue trying specified starting values for pressure until a calculation

converges. The critical point of the fluid system can easily be estimated by

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noting the change in saturation pressure type from bubblepoint to

dewpoint.

Figure 7-25 shows the input menu for simulating the dew/bubblepoint

phase envelope calculation.

Figure 7-25: Phase Envelope Calculation







■ Lowest Temp /Upper Envelope. The lowest temperature used to

calculate saturation pressure for the upper portion of the phase

envelope. This is required input. (Default is 0)

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■ Highest Temp /Upper Envelope. The highest temperature used to

calculate saturation pressure for the upper portion of the phase


■ Temp Increment/Upper Envelope. The increment used to select

values from the lowest to the highest temperature for the upper

portion of the phase envelope. This is required input. (Default is 50)

■ Lowest Temp /Lower Envelope. The lowest temperature used to

calculate saturation pressure for the lower portion of the phase


■ Highest Temp /Lower Envelope. The highest temperature used to

calculate saturation pressure for the lower portion of the phase


■ Temp Increment/Lower Envelope. The increment used in selecting

temperature values from the lowest to the highest temperature for the

lower portion of the phase envelope. This is required input. (Default

is 50)

■ Lowest Pres /Upper Envelope. The lowest pressure used to initialize

the saturation pressure calculation for the upper portion of the phase


■ Highest Pres /Upper Envelope. The highest pressure used to initialize

the saturation pressure calculation for the upper portion of the phase


■ Pres Increment /Upper Envelope. The increment used to select

pressure values from the lowest to the highest pressure for the upper

portion of the phase envelope. This is required input. (Default is

2000)

■ Lowest Pres /Lower Envelope. The lowest pressure used to initialize

the saturation pressure calculation for the lower portion of the phase


■ Highest Pres /Lower Envelope. The highest pressure used to initialize

the saturation pressure calculation for the lower portion of the phase


■ Pres Increment /Lower Envelope. The increment used to select

pressure values from the lowest to the highest pressure for the lower

portion of the phase envelope. This is required input. (Default is 100)

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7.3.12 Gas Enthalpy: Gas Enthalpy

The enthalpy of a gas mixture (ENTHV) is calculated as a function of its

temperature and pressure. Figure 7-26 shows the input menu for

calculating the enthalpy of gas mixtures.

Figure 7-26: Gas Enthalpy Menu

■ Composition. The composition of the gas mixture in mole fraction.








■ Enthalpy Unit. The enthalpy units which are the same for all enthalpy

measurements in this test. This is required input. (Default is KBTU/

LBMOLE)

■ Density/Z-Factor Option. Alpha label specifying whether density or

z-factor is measured and reported. This is required input.

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❑ Density. Density is measured.

❑ Z-Factor. Z-Factor is measured. (Default)




including pressure, enthalpy, and density or z-factor. The detailed





measured gas antelope data. The data are measured at two pressure stages

in this example.

Figure 7-27: Data Entry Table for Gas Enthalpy


■ Enthalpy. The gas enthalpies measured at the pressure stages.

■ Z-Factor or Density. The gas z-factors, or densities, measured at the

pressure stages.

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7.3.13 Liquid Enthalpy: Liquid Enthalpy

The enthalpy of a liquid mixture (ENTHL) is calculated as a function of its

temperature and pressure. Figure 7-28 shows the input menu for

calculating the enthalpy of liquid mixtures.

Figure 7-28: Liquid Enthalpy

■ Composition. The composition of the liquid mixture in mole fraction.








■ Enthalpy Unit. The enthalpy units which are the same for all enthalpy

measurements in this test. This is required input. (Default is KBTU/

LBMOLE)

■ Density/Z-Factor Option. Alpha label specifying whether density or

z-factor is measured and reported. This is required input.

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❑ Density. Density is measured.

❑ Z-Factor. Z-Factor is measured. (Default)




including pressure, enthalpy, and density or z-factor. The detailed



measured liquid antelope data. The data are measured at two pressure

stages in this example.

Figure 7-29: Data Entry Table for Liquid Enthalpy



■ Pressure. The pressure stages at which data were measured. This is

required input.

■ Enthalpy. The liquid enthalpies measured at the pressure stages.

■ Z-Factor or Density. The liquid z-factors, or densities, measured at the

pressure stages.

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7.3.14 Water Property: Liquid Water Property

The liquid water properties (WATPRP) of density, enthalpy, viscosity and

fugacity coefficient are calculated as a function of pressure and

temperature. Figure 7-30 shows the input menu for calculating the liquid

water property.

Figure 7-30: Water Property Menu

■ Pressure. Pressure, in psia. This is required input.

■ Temperature. Temperature, in degrees Fahrenheit. This is requiredinput.

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7.3.15 Sat Pressure/H2O: Bubblepoint Pressure of Mixture With Water

The bubblepoint pressure of oil in the presence of water (PSATW) is

calculated as a function of temperature in this test. If the water-in-oil

option has been selected, then the bubblepoint pressure may also be a

function of the amount of water present (only if the oil is undersaturated

with water). For this option, the COMPOSITION entry specifies the water-

free oil composition. Since DESKTOP-PVT loads the water component

and its properties automatically for this test, it is not necessary to input

water (H2O) as a component in the component assignment process. An

input menu for the binary coefficients of water and other components will

be displayed by activating the Thermal option in the Config menu.

Figure 7-31 shows the input menu for calculating the bubblepoint

pressure of oil in the presence of water.

Figure 7-31: BubblepointPressure of Mixture with H2O Menu

■ Composition. The composition of the water-free oil in mole fraction.








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including temperature, overall water mole fraction, bubblepoint

pressure, density, and z-factor. The detailed table entries are discussed

later.


measured data. The default weight factors are 10 for bubblepoint

pressures, and 5 for both densities and z-factors.

Figure 7-32 also shows an example of the table for entering bubblepoint

pressures of oil in the presence of water. The bubblepoint pressures are

measured at one temperature stage in this example.

Figure 7-32: Data Entry Table for Bubblepoint Pressure of Mixture with H2O

■ Temp. The temperature at which bubblepoint pressures are measured

in this test. This is required input.

■ Zwat. Overall water mole fraction in the water/oil system. This is

required input.

■ Bubble Pt. The measured bubblepoint pressures at the temperature

stages. A realistic value should be entered even if no data is available.

This data is used as the starting value for the bubble pressure

calculation. A poor estimate can result in convergence failure. This isrequired input.


temperatures and bubblepoint pressures.


temperatures and bubblepoint pressures.

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7.3.16 Distillation: Distillation Test

The laboratory distillation (DISTIL) test starts with an oil sample at its

boiling point temperature. The oil sample is distilled by increasing

temperature in a sequence of discrete steps at a constant pressure. The

distillate is condensed, and its volume or weight is measured and

reported. Figure 7-33 shows the input menu for simulating the distillation

test.

Figure 7-33: Distillation Test Menu





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■ Operating Pressure. The operating pressure of the distillation test.

This is required input. (Default is 0)



■ Boiling Point Temperature (Tbp). The boiling point temperature

(temperature at zero distillate volume or weight fraction) of the oil

sample. This is required input.

■ Weight Factor/Tbp. The regression weight factor of the measured

boiling point temperature. (Default is 2)


■ Standard Pressure. Standard pressure. (Default is 0)

■ Distillate Fraction Option. Alpha label specifying the units of the

distillate fraction on the distillation curve. This is required input.

❑ VOLUME. Volume fraction. Cumulative volume distillated

divided by initial oil volume with all volumes measured at the

standard conditions. (Default)

❑ WEIGHT. Weight fraction. Cumulative weight distillated divided

by initial oil weight.

■ Distillation Curve. The laboratory measured distillation data

including temperature and distillate volume, or weight, fraction. The

detailed table entries are discussed later. This is required input.

■ Temp Increment In Calculation. The temperature increment used in

stepping through the distillation curve calculation. This is requiredinput. (Default is 5)

■ Molecular Weight Measurements. The laboratory measured

molecular weights of the heavy fraction in the crude oil and residues,

and the weight fraction of the heavy fraction in the crude oil. The


■ Crude API Gravity (APIc). The measured API gravity of original

crude.

■ Weight Factor/APIc. The regression weight factor of the measured API

gravity of the original crude. (Default is 1)

■ Residue API Gravity Table. The measured API gravities of residues

on distillation curve. The detailed table entries are discussed later.

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■ Distillate Property Tables. Tables of distillate API gravity, distillate

component K-values, and weight factor tables of the measured

distillate component K-values. The detailed table entries are discussed

later.

■ Blend Fraction Option. Alpha label specifying the units for which

fractions of the original crude, residue and distillate are mixed in

preparing the blend. This is required input.

❑ VOLUME. Volume fractions are used to specify the amount of

original crude, residue, and distillate in the blend. (Default)

❑ WEIGHT. Weight fractions are used to specify the amount of

original crude, residue, and distillate in the blend.

■ Blend API Gravity Table. The measured API gravities of blends. The


■ Viscosity Measurements. The measured viscosities of the original

crude, residues, distillate and blends. The detailed table entries are

discussed later.

Distillation Curve

Figure 7-34 shows the menu for entering laboratory measured distillation

data.

Figure 7-34: Data Entry Table for Distillation Curve

■ Temperature. The temperature on distillation curve. The temperature

must be in increasing order. This is required input.

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■ Volume Frac or Weight Frac. The distillate volume or weight fraction

on distillation curve. See Distillate Fraction Option above for the

definition of the volume and weight fractions.

■ Weight Factor. The regression weight factors of the measured distillate

volume or weight fraction. (Default is 1)

Molecular Weight Measurements

Figure 7-35 shows an example of the table for entering molecular weight

data for the heavy fraction.

Figure 7-35: Data Entry Table for Distillation Molecular Weight Measurements

■ M.W., Crude Heavy Frac (MWc). The molecular weight of the heavy

fraction of the original crude.

■ Weight Factor/ MWc. The regression weight factor for the measured

molecular weight of the heavy fraction of the original crude. (Default

is 1)

■ First Heavy Component Name/MWc. The component name of the

lowest molecular weight component in the heavy fraction for which

molecular weight of the crude heavy fraction is being reported.

R2003.0 - Landmark 7-117


■ Last Heavy Component Name/MWc. The component name of the

highest molecular weight component in the heavy fraction for which

molecular weight of the crude heavy fraction is being reported.

■ M.W., Residue Heavy Fraction. This table is used for entering the

measured molecular weight of the heavy fraction of the residues. The

entries are the same as the above four items, except the data entry

number on the distillation curve may also be input.

■ Wt Frac, Crude Heavy Frac (Wt). The measured weight fraction of the

crude heavy fraction in the original crude.

■ Weight Factor/Wt. The regression weight factor for the measured

weight fraction of the crude heavy fraction in the original crude.

(Default is 1)

■ First Heavy Component Name/Wt. The component name of the

lowest molecular weight component in the heavy fraction for which

weight fraction of the crude heavy fraction is being reported.

■ Last Heavy Component Name/Wt. The component name of the

highest molecular weight component in the heavy fraction for which

weight fraction of the crude heavy fraction is being reported.

Residue API Gravity Data

Figure 7-36 shows the menu for entering residue API gravity data.

Figure 7-36: Data Entry Table for Distillation Residue API Gravity

■ Residue API. The measured API gravity of residue on the distillation

curve.

■ Weight Factor. The regression weight factor for the measured API

gravity of residue. (Default is 1)

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■ Dstl Curve No. The data entry number on the distillation curve.

Distillate Property Tables

There are four tables available for data entry (Figure 7-37):

■ Distillate API Gravity

■ Component K-Value Table

■ Weight Factor/Component K-Value (vs. EOS K-Value)

■ Weight Factor/Component K-Value (vs. Correlation K-Value)

Figure 7-37: Data Entry Table for Distillate Property Tables

A file contains computed distillate K-values will be generated, can be

saved later. The format of the file is syntactically correct for input into VIP-

THERM.

Distillate API Gravity

Figure 7-38 shows the menu for entering distillate API gravity data.

Figure 7-38: Data Entry Table for Distillation Distillate API Gravity

R2003.0 - Landmark 7-119


■ Distillate API. The measured API gravity of distillate. The

temperature range of the distillate is specified by Start Curve No. and

End Curve No.

■ Weight Factor. The regression weight factor for the measured API

gravity of the distillate. (Default is 1)

■ Start Curve No. The data entry number on the distillation curve which

defines the starting temperature of the distillate.

■ End Curve No. The data entry number on the distillation curve which

defines the ending temperature of the distillate.

Component K-Value Table

Figure 7-39 shows the menu for entering component K-values of the

distillate.

Figure 7-39: Data Entry Table for Distillate K-Value

■ Distillate No. Distillate fraction number.

■ All other columns. Component K-values.

Weight Factor/Component K-Value (vs. EOS K-Value)

Figure 7-40 shows the menu for entering regression weight factors for the

measured component K-values. This weight factor is applied to the

residuals of equation-of-state computed K-values and measured K-values.

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To accommodate the large variation in component K-values, the logarithm

of the K-values are used in computing the residuals.

Figure 7-40: Weight Factor for Distillate K-Value

Weight Factor/Component K-Value (vs. Correlation K-Value)

There is another regression weight factor table for the measured K-values

but is applied only to the residuals of correlation computed K-values and

measured K-values (Figure 7-41). To accommodate the large variation in

component K-values, the logarithm of the K-values are used in computing

the residuals. This weight factor will not affect the adjustment of equation-

of-state parameters in regression.

Figure 7-41: Weight Factor for Distillate K-Value

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Blend API Gravity Data

Figure 7-42 shows the menu for entering blend API gravity data.

Figure 7-42: Data Entry Table for Distillation Blend API Gravity

■ Crude Frac. The volume or weight fraction of the original crude in the

blend.

■ DstCurve No. The data entry number on the distillation curve for the

residue used in the blend.

■ Resd Vol Fr or Resd Wt Fr. The volume or weight fraction of the

residue with the temperature specified by DstCurve No.

■ Distillate No. The data entry number of the distillate in the Distillate

API Gravity Table for the distillate used in the blend.

■ Dstl Vol Fr or Dstl Wt Fr. The Volume or weight fraction of the

distillate specified by Distillate No.

■ Blend API. The measured API gravity of the blend.

■ Wt Factor. The regression weight factor for the measured API gravity

of the blend. (Default is 1)

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Viscosity Measurements

Figure 7-43 shows the menu for entering viscosity data.

Figure 7-43: Viscosity Data for Distillation Test

■ Minimum Viscosity (cp). The limiting viscosity (cp) as temperature

approaches infinity. The default value is 0.2. This value is used only in

plotting the viscosity data in the form of

(7-1)

where T is absolute temperature.

■ Crude Viscosity (cp). The data table for the measured viscosities of the

original crude.

■ Residue Viscosity (cp). The data table for the measured viscosities of

the residues.

■ Distillate Viscosity (cp). The data table for the measured viscosities of

the distillates.

■ Blend Viscosity (cp). The data table for the measured viscosities of the

blends.

ln ln µ 1 vmin–+( )( ) A B ln T( )+=

R2003.0 - Landmark 7-123


Figure 7-44 shows the data table for the original crude viscosity.

Figure 7-44: Data Entry Table for Crude Viscosity

■ Temp. Temperature of the measured viscosity. The units are the same

as those specified in the main menu of the distillation test.

■ Pres. Pressure of the measured viscosity. The units are the same as

those specified in the main menu of the distillation test.

■ Visc. Measured viscosity (cp) of the original crude.

■ Wt Factor. The regression weight factor for the measured viscosity of

the original crude.

If one of the Twu viscosity correlations is selected, a viscosity data file will

be generated. This file will contain component viscosity data at the

temperatures specified in the crude viscosity table. The file can be saved

later and used in VIP-THERM.

Figure 7-45 shows the menu for entering residue viscosity.

Figure 7-45: Data Entry Table for Residue Viscosity

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■ Curve No. The data entry number on the distillation curve.





■ Visc. Measured residue viscosity (cp).

■ Wt Factor. The regression weight factor for the measured residue

viscosity.

Figure 7-46 shows the menu for entering distillate viscosity.

Figure 7-46: Data Entry Table for Distillate Viscosity

■ Distl. No. The distillate fraction number.





■ Visc. Measured distillate viscosity (cp).

■ Wt Factor. The regression weight factor for the measured distillate

viscosity.

R2003.0 - Landmark 7-125


Figure 7-47 shows the menu for entering blend viscosity.

Figure 7-47: Data Entry Table for Blend Viscosity

■ Blend No. The blend number.





■ Visc. Measured blend viscosity (cp).

■ Wt Factor. The regression weight factor for the measured blend

viscosity.

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7.3.17 Steam Distillatn: Steam Distillation Test

The laboratory steam distillation (STMDIS) test is performed with an oil

sample at constant pressure and temperature. The oil sample is distilled

by continuous injection of superheated or saturated steam with a quality

of one. The distilled fluid is condensed and its volume is measured and

reported.

Since DESKTOP-PVT will load the water component and its properties

automatically for this test, it is not necessary to input water (H2O) as a

component in the component assignment process. An additional input

menu for the binary coefficients of water and other components can be

displayed by activating the Thermal option in the Config menu.

Figure 7-48 shows the input menu for simulating the steam distillation

test.

Figure 7-48: Steam Distillation Menu

R2003.0 - Landmark 7-127






■ Operating Pressure. The operating pressure (pressure of the injected

steam) of the steam distillation test. The program will calculate the

steam saturation pressure at the injected steam temperature. If the

calculated steam saturation pressure is less than the input operating

pressure, the calculated saturation pressure is used as the operating

pressure in the calculation. This is because the injected steam must

either be superheated or saturated with a quality of one. This isrequired input.



■ Temperature of Injected Steam. The temperature of the injected

steam. This is required input.


■ Standard Pressure. Standard pressure. (Default is 0)

■ No. of Equilibrium Stages. Number of equilibrium stages used for

simulating the steam distillation process. A maximum of five stages is

allowed. (Default is 1)

■ Injected Steam Rate. Injected steam rate, in gm/hr. This is requiredinput.

■ Initial Oil Volume In Cell. The volume of crude oil initially injected

into the PVT cell, in cubic centimeters (cc). This is required input.

■ API Gravity, Initial Oil (APIo). The API gravity of the original crude.


■ Weight Factor/APIo. The regression weight factor of the measured

API gravity of the original crude. (Default is 1)

■ Lab Measurements (Lab Data). The table for entering laboratory

measured data such as injected steam volume, steam distillation yield

and density of the distilled oil. The detailed table entries are discussed

later.

■ Weight Factor/ Lab Data. The regression weight factors of the

measured data (Default is 1)

■ Time-Step Size. Time-Step size, in hours, used for simulating the

steam distillation process. This is required input.

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Figure 7-49 shows the table for entering laboratory measured steam

distillation data.

Figure 7-49: Data Entry Table for Steam Distillation

■ Inj Steam Volume. Steam Distillation factor. Cumulative volume of

injected steam in the equivalent water volume divided by the initial oil

volume. This is required input.

■ Distil Yield. Steam distillation yield. Cumulative volume of oil

distilled divided by the initial oil volume, with all volumes measured

at standard conditions. Distilled oil is assumed to be all liquid at

standard conditions. This may not be adequate for light oils since gas

may be produced.

■ Oil Dens. Density of distillate fraction at standard conditions, in gm/

cc.

R2003.0 - Landmark 7-129


7.3.18 Separator/No Reg: Multistage Separators Without Regression

DESKTOP-PVT can model the behavior of multistage surface separator

facilities (SEPARATOR) in predictive mode. Each separator battery may

contain an arbitrary number of stages. Each stage contains one feed stream

and two output streams, one vapor and one liquid. Each of the two output

streams can be split into two streams that may be fed into a downstream

separator stage, the gas sales line or the oil sales line.

Figure 7-50 shows the input menu for simulating the multistage

separators.

Figure 7-50: Multi-State Separator Menu

■ Separator Battery No. The separator battery number. This is requiredinput. (Default is 1)





■ Produced Volume Units: In English units, produced gas is reported in

SCF; GOR is reported in SCF/STB; and stage liquid production is

reported in RB. In metric units, produced gas is reported in standard

cubic meters; GOR is reported in standard cubic meters of gas per

standard cubic meters of oil; and stage liquid production is reported in

reservor cubic meters. (Default is ENGLISH)

■ Separator Conditions. The separator conditions data including the

number of separator stages, the temperature and pressure of each

stage, and the destinations of the output streams. The detailed table


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Figure 7-51 also shows the table used for entering the separator conditions

data. For each stage, a maximum of two destinations can be assigned for

each of the two output streams (vapor and liquid). For example, the liquid

stream leaving a separator can be sent to the oil sales line, or a fraction of

the liquid stream can be sent to the oil sale line with the rest of the liquid

stream sent to a downstream separator. If the output streams are sent to

two destinations, then two data cards, one for each destination, are

required for a complete description of the stage conditions (type 1 and

type 2 data cards). Otherwise, only one data card is needed for each stage

(type 1 card). Type 2 data cards, if required, must immediately follow type

1 data cards for each stage.

Figure 7-51: Data Entry Table for Multi-Stage Separator

■ Stage No. The separator stage number. Every separator must have an

(positive) integer stage number. The nonzero stage number indicates a

type 1 data card. If a type 2 data card is required for a separator stage,

enter 0 for the Stage No. This is required input.

■ Temperature. The operating temperature of a separator stage. A

temperature value is required for type 1 data cards. Enter 0 for type 2

data cards. This is required input.

■ Pressure. The operating pressure of a separator stage. A pressure

value is required for type 1 data cards. Enter 0 for type 2 data cards.


■ Vapor Frac. The fraction of the vapor stream leaving a separator stage

is sent to the destination indicated in Vapor Dest. Values must lie in the

range of 0 to 1. If the value for a type 1 data card is less than one, a type

2 data card must be provided for this stage. This is required input.

R2003.0 - Landmark 7-131


■ Vapor Dest. Defines the destination of the vapor stream leaving a

separator stage. Destinations include a downstream separator stage

and the gas sales line. Enter the alpha label GAS if the destination is

the gas sales line, otherwise enter a downstream separator stage

number. This is required input.

■ Liquid Frac. The fraction of the liquid stream leaving a separator stage

is sent to the destination indicated in Liquid Dest. Values must lie in

the range of 0 to 1. If the value for a type 1 data card is less than one,

then a type 2 data card must be provided for this stage. This isrequired input.

■ Liquid Dest. Defines the destination of the liquid stream leaving a

separator stage. Destinations include a downstream separator stage

and the oil sales line. Enter the alpha label OIL if the destination is the

oil sales line, otherwise enter a downstream separator stage number.


7.3.19 Separator/Reg: Laboratory Separator Test With Regression

A laboratory separator (SEP) test may be calculated in DESKTOP-PVT as a

prediction, or through regression where experimental data is matched.

The user may enter equation-of-state parameters of omega A and/or

omega B for either reservoir calculations or surface calculations. These

omega A and omega B parameters override the ones entered in the Fluid

Properties table. The user must explicitly override the reservoir omega A

and omega B parameters by responding YES to the dialog box.

During a regression run, if either separator or reservoir parameters are

overriden, they will remain constant for the separator calculations even if

they are selected as regression variables. In this way, regressions can be

run to independently match reservoir and separator parameters. For

example, if the user wished to regress on separator omega A and B and

wished to keep the reservoir omega A and B constant, the user should

click on the reservoir buttons, optionally change the values, and then enter

YES when prompted. On the other hand, if the user wished to regress on

reservoir omega A and B while keeping the separator omega A and B

constant, the user should click on the reservoir buttons, and respond NO

when prompted, and the user should manually enter omega A and B

values for the separator.

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Figure 7-52 shows the input menu for simulating the laboratory separators

test.

Figure 7-52: Laboratory Separator Test Menu



■ Omega A & B/Reservoir. The components, omega A and B, of

equation-of-state parameters at reservoir conditions. The default

values are the same as the initial values in the Property table in the

Fluid menu. If the user changes any of the values in the table, the user

must explicitly choose that these values remain constant for them to

take effect. Conversely, the user can choose that these values remain

constant even if they have not been changed from the initial values.

R2003.0 - Landmark 7-133


■ Omega A /Separator. The component, omega A, of equation-of-state

parameters at separator conditions. The default values are the same as

the initial values in the Property table in the Fluid menu.

■ Omega B /Separator. The component, omega B, of equation-of-state

parameters at separator conditions. The default values are the same as

the initial values in the Property table in the Fluid menu.



■ Temperature/Reservoir. The reservoir temperature. This is requiredinput.





BUBPT)


reservoir temperature. This is required input.

■ Gas-Oil Ratio (GOR) Unit. The units for all gas-oil ratio

measurements. This is required input. (Default is SCF/STB)



■ Oil Density or Gas Z-Factor. Oil density (for bubblepoint fluid) or Gas

Z-factor (for dewpoint fluid) at reservoir temperature and saturation

pressure.


■ Standard Pressure. Standard pressure. (Default is 14.7)

■ Oil/Gas Formation Volume Factor: Bo/Bg. Oil formation volume

factor (for bubblepoint fluid) in barrels of saturated oil at bubble-point

pressure and reservoir temperature per barrel of stock tank oil at

standard conditions, or gas formation volume factor (for dewpoint

fluid) in barrels of gas at dewpoint pressure and reservoir temperature

per thousand standard cubic feet of gas.

■ Weight Factor/Bo or Bg. The regression weight factor of the oil or gas

formation volume factor. (Default is 1)

■ Stock Tank Oil API Gravity. The API gravity of stock tank oil at

standard conditions.

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■ Weight Factor/Oil API. The regression weight factor of the API

gravity of stock tank oil at standard conditions. (Default is 1)

■ Total Gas-Oil Ratio (TGOR). The total gas-oil ratio, in standard cubic

feet of gas per stock tank barrel of oil, calculated by separation through

all stages to surface conditions.

■ Weight Factor/TGOR. The regression weight factor of total gas-oil

ratio. (Default is 1)


including pressure, temperature, gas-oil ratio, separator volume factor,

and gas specific gravity. The detailed table entries are discussed later.



Figure 7-53 shows the table for entering laboratory measured separator

data.

Figure 7-53: Data Entry Table for Laboratory Separator Test

■ Pressure. The operating pressure of a separator stage. This is requiredinput.

■ Temperature. The operating temperature of a separator stage. This isrequired input.

■ GOR/Stage P&T. Gas-oil ratio in cubic feet of gas at standard

conditions per barrel of oil at stage pressure and temperature.

■ GOR/Std P&T. Gas-oil ratio in cubic feet of gas at standard conditions

per barrel of stock tank oil at standard conditions.

■ Oil Vol Fact. Separator volume factor in barrels of oil at stage pressure

and temperature per barrel of stock tank oil at standard conditions.

■ Gas Gravity. Specific gravity of stage flashed gas.

R2003.0 - Landmark 7-135


7.3.20 Phas Envlop/Full: Complete Phase Envelope

The boundary of the two-phase region and the quality lines inside the

two-phase region are calculated in complete phase envelope (ENVPT).

The quality lines can be specified as either liquid mole fraction or liquid

volume fraction. The step-sizes for temperature and pressure are adjusted

automatically so the computation can be performed in an efficient manner

while giving a clear picture of the phase envelope.

Figure 7-54 shows the input menu for calculating phase envelope.

Figure 7-54: Complete Phase Envelope Menu







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■ Lowest Temperature. The lowest temperature used to calculate

equilibrium pressure. This is required input. (Default is 0)

■ Highest Temperature. The highest temperature used to calculate

equilibrium pressure. This is required input. (Default is 800)

■ Temperature Increment. The maximum temperature increment

allowed in calculating phase envelope. This is required input.(Default is 25)

■ Lowest Pressure. The lowest pressure used to calculate equilibrium

temperature and initialize equilibrium pressure calculation. This isrequired input. (Default is 14.7)

■ Highest Pressure. The highest pressure used to calculate equilibrium

temperature and initialize equilibrium pressure calculation. This isrequired input. (Default is 8014.7)

■ Pressure Increment. The maximum pressure increment allowed in

calculating phase envelope. This is required input. (Default is 250)

■ Liquid Fraction Type. Alpha label specifying either liquid mole

fraction or liquid volume fraction quality line. This is required input.

❑ LIQMF. Calculate liquid mole fraction quality line. (Default)

❑ LIQSAT. Calculate liquid volume fraction quality line.

■ Liquid Fraction Table. The values of liquid qualities in fraction. Thisis required input. (Defaults are 0, 0.25, 0.5, 0.75 and 1.0)

7.3.21 ZGRAD: Composition Variations With Depth

Considerable variations of hydrocarbon composition with depth have

been observed in several near critical reservoirs. In the top part of the

reservoir, the compositions are such that the fluid is classified as a gas

condensate. The heavy component composition increases as a function of

depth so that the fluid would be classified as a volatile oil at the bottom of

the reservoir. At some depth in the reservoir, the fluid would change

classification from gas to oil, but there is no classical gas-oil contact and no

two-phase region. This is because the hydrocarbon compositions are

always at temperatures and pressures that do not cross the equilibrium

two-phase envelope.

The composition variations of hydrocarbon fluids in an isothermal

reservoir are calculated in this test. We assume that the fluid has reached

the stationary state and no two-phase region exists in the reservoir. Only

the fluid component fugacities and gravity forces are considered in

calculating the composition variations. In addition to the tabular and

graphical reports, a file is written at the end of calculation and can be save

R2003.0 - Landmark 7-137


later. This file contains the composition information that can be exported

directly to VIP-COMP.

Figure 7-55 shows the input menu for calculating composition variations

with depth. The input data are reservoir temperature, pressure and

hydrocarbon composition at a reference depth.

Figure 7-55: Composition Variations with Depth Menu

■ Composition. The hydrocarbon composition at the reference depth in




■ Temperature. The reservoir temperature. This is required input.(Default is 100)



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■ Reservoir Pressure. The reservoir pressure at the reference depth. Thisis required input. (Default is 2000)



BUBPT)


reference depth. This is required input.

■ Depth Unit. The depth units which are the same for all depth

measurements. This is required input. (Default is FT)

■ Reference Depth. The reference depth where composition,

temperature, pressure and saturation pressure are measured. This isrequired input.

■ Option For Entering Depth. Two options are available to enter the

depths where compositions are calculated.

❑ Dvalue. The numerical values of depth will be entered directly.

❑ Dinc. The numerical values of depth are computed by specifying

the maximum, minimum and increment of depth. This is requiredinput. (Default is Dvalue)

■ Depth. The reservoir depth (positive downward) if Dvalue above is

selected, or the maximum depth, minimum depth and depth

increment if Dinc above is selected. This is required input.

■ Equilibrium Composition (ZCOMP). The measured overall

compositions in mole fraction at depth entries.

■ Weight Factor/ZCOMP. The regression weight factors of measured

overall compositions. (Default is 1)

■ Optional Input. An item for activating the optional input menu for

this test. The detailed entries are discussed later.

R2003.0 - Landmark 7-139


Figure 7-56 shows the Optional Input menu for calculating composition

variations with depth.

Figure 7-56: Optional Input for Composition Variables with Depth

■ Calculation Method. Two calculation methods available.

❑ NEWTON. Newton-Raphson method (Default)

❑ SS. Successive-substitution method

■ Max No. of Iterations. The maximum number of iterations allowed to

compute composition at a depth. (Default is 40)

■ Max Pressure Change /Iter. The maximum change in pressure for an

iteration. (Default is 10)

■ Max Composition Change/Iter. The maximum change in composition

for an iteration. (Default is 0.01)

■ Pressure Convergence Tol. Convergence tolerance for pressure

change between iterations. (Default is 0.01)

■ Composition Convergence Tol. Convergence tolerance for

composition change between iterations. (Default is 0.00001)

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■ Min Damping Factor. Convergence tolerance for the damping factor

of the pressure and composition changes between iterations. The

composition calculation will fail if the computed damping factor is less

than the tolerance. (Default is 0.001)

■ Min Depth Interval for Calc. The minimum depth interval allowed in

the composition calculation. If the computed depth interval is less than

this minimum value, the calculation will be reported as a failure.

(Default is 1)

■ Max Depth Interval for Calc. The maximum depth interval allowed in

the composition calculation. If the user specified depth interval is

greater than this value, the compositions at additional intermediate

depths will be performed with this depth interval between the user

specified depths. (Default is 100)

■ Depth Interval Reduction Scale. The factor for reducing the size of

depth interval when a composition calculation fails. If the composition

calculation which failed was of size of ∆D, the next intermediate

composition calculation will be of size ∆D times this factor. (Default is

0.2)

■ Debug Output Option. The user may request additional output of

composition calculation by turning on the debug output option.

❑ ON. Activate printing of detailed calculation output.

❑ OFF. Deactivate printing of detailed calculation output (Default).

7.3.22 CO2TAB: Properties of Carbon Dioxide Saturated Water

Properties of carbon dioxide saturated water are calculated using

correlations in this test. The correlations are shown in Section 5.2.7. These

properties include carbon dioxide solubility, formation volume factor,

compressibility and viscosity. In addition to the tabular and graphical

reports, a file named “co2tab.log” is written at the end of calculation. This

file contains the properties of carbon dioxide saturated water that can be

exported directly to VIP-COMP.

R2003.0 - Landmark 7-141


Figure 7-57 shows the input menu for calculating properties of carbon

dioxide saturated water.

Figure 7-57: Calculating Properties of Carbon Dioxide Saturated Water

■ Format of Data Table. Alpha label specifying the table format to enter

carbon dioxide saturated water properties. This is required input.

(Default is SATWAT) Only SATWAT option will generate enough data

in “co2tab.log” file to be used by VIP-COMP, and is explained in the

documentation.

Seven options are available:

❑ SATWAT saturated water properties of solubility, formation

volume factor, compressibility and viscosity as a function of

pressure at specified temperature and salinity.

❑ PTTAB solubility of carbon dioxide in water as a function of

pressure (row entry) and temperature (column entry) at a specified

salinity.

❑ TPTAB solubility of carbon dioxide in water as a function of

temperature (row entry) and pressure (column entry) at a specified

salinity.

❑ PSTAB solubility of carbon dioxide in water as a function of

pressure (row entry) and salinity (column entry) at a specified

temperature.

❑ SPTAB solubility of carbon dioxide in water as a function of

salinity (row entry) and pressure (column entry) at a specified

temperature.

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❑ TSTAB solubility of carbon dioxide in water as a function of

temperature (row entry) and salinity (column entry) at a specified

pressure.

❑ STTAB solubility of carbon dioxide in water as a function of

salinity (row entry) and temperature (column entry) at a specified

pressure.

■ Salinity Units. The brine salinity units. There are two options

❑ WT% weight percent of solid

❑ PPM parts per million of solid

This is required input. (Default is WT%)

■ Temperature Units. The temperature units which are the same for all

temperature measurements in this test. This is required input. (Default

is F)

■ Pressure Units. The pressure units which are the same for all pressure


■ Laboratory Data. The laboratory measured data for SATWAT option

include salinity, temperature and properties of carbon dioxide

saturated water.

Figure 7-58 shows the input menu for entering laboratory measured data

for SATWAT option.

Figure 7-58: Laboratory Measured Data for SATWAT Option

■ Salinity (WT%). Salinity of the brine in the units shown in

parentheses. This is required input. (Default is 0)

R2003.0 - Landmark 7-143


■ Temperature. The temperature at which all data are measured. This is

required input. (Default is 0)

■ Properties of CO2. The laboratory measured data for carbon dioxide

Saturated Water saturated water include solubility, formation volume

factor, compressibility and viscosity. The detailed entries are discussed

later.

■ Weight Factor. The regression weight factors for the measured data of

carbon dioxide saturated water. (Default is 1)

Figure 7-59 shows the input menu for entering measured data of carbon

dioxide saturated water.

Figure 7-59: Measured Data of Carbon Dioxide Saturated Water

■ Pressure. Pressures at which data were measured. The pressures must

be in decreasing order. This is required input.

■ Rsw. solubility of carbon dioxide in water at the specified pressure,

temperature and salinity. The units are scf/stb if the pressure units are

psia and are scm/stcm if the pressure units are kpa.

■ Bw. Formation volume factor of carbon dioxide saturated water. The

units are rb/stb if the pressure units are psia and are cm/stcm if the

pressure units are kpa.

■ Cw. Compressibility of carbon dioxide saturated water. The units are

inverse of pressure units.

■ Viscosity. Viscosity of carbon dioxide saturated water in cp.

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7.3.23 Steam Vaporizatn: Multiple Contact Steam Vaporization

A multiple contact steam vaporization (MCSVAP) test is a stepwise batch

experiment which can be calculated as a prediction or through regression

where experimental data is matched.

A specified initial amount of oil and optionally a specified initial amount

of water are charged into the PVT cell. For each contact, a specified

amount of steam (or water) is injected into the PVT cell and the fluids are

brought to equilibrium at a temperature, pressure and cell volume such

that a vapor phase is formed. A liquid water phase may or may not be

formed. The total cell volume, the amount of vapor phase formed at

equilibrium and the equilibrium gas, oil and water saturations are

measured. Then the vapor phase is completely removed from the PVT cell

and is flashed to standard conditions. The produced amounts of gas, oil

and water are measured.

The amounts of initial oil and water, the injected steam, and produced

fluids may be expressed in mass (default), volumetric or molar units. For

the volumetric unit option, the units are cubic centimeter (cc). The initial

volume of oil, and the produced volumes of gas, oil and water are

measured at standard conditions. The volumes of initial water and

injected steam are expressed in terms of H2O cwe (cold water equivalent).

Only the vapor phase volume at equilibrium is measured at PVT cell

conditions. For cases in which the initial oil is saturated at standard

conditions, the volumetric unit option should not be used. This condition

is not checked by the program.

Optionally, oil viscosities of the initial oil (crude), and of the PVT cell oil

and the produced oil for any contact may also be calculated as predictions

or through regression to match experimental data. Care should be taken to

insure that the specified temperatures and pressures at which viscosities

are to be calculated correspond to undersaturated conditions for the

relevant fluid composition. This is not checked by the program.

The program utilizes rigorous three phase flash algorithms for

equilibrium calculations both in the PVT cell and the separator. For most

heavy oils, the fluid in the separator will be an undersaturated oil/water

mixture (no produced gas). If this condition is detected by calculation of

the bubblepoint, the separator flash calculation is of course bypassed.

Water is allowed to partition into the oil phase in all equilibrium/

bubblepoint calculations if the water-in-oil option has been selected.

Normally, H2O should not be defined as a component by the user. H2O is

defined implicitly and is treated by the equation of state as a component in

the gas and (optionally) oil phase with fixed properties which are

consistent with those used in VIP-THERM. The only properties associated

with H2O which may be modified by the user are the binary interaction

coefficients.

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Figure 7-60 shows an example of the main input menu for simulating the

MCSVAP test.

Figure 7-60: Simulating the MCSVAP Test

■ Composition. The composition of the initial oil in mole fraction. This

is required input.


temperature measurements in this test. This is required input. (Default

is F, degree Fahrenheit.)



■ Stream Unit. The stream units which are the same for all stream

measurements in this test, including the amounts of initial oil and

water, the injected steam, and produced fluids. This is required input.

(Default is G, grams.)


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■ Standard Pressure. Standard pressure. (default is 14.7)

■ API Gravity of Initial Oil (APIo). The API gravity of the initial oil.

Use only if initial oil is undersaturated.

■ Weight Factor/APIo. The regression weight factor of the measured

API gravity of the initial oil. (Default is 1)

■ Initial Quantity of Oil in Cell. Initial amount of oil in PVT cell in the

units specified by Stream Unit. This is required input. (Default is 100)

■ Initial Quantity of H2O in Cell. Initial amount of water in PVT cell in

the units specified by Stream Unit. (Default is 0)

■ Lab Measurements (Lab Data). The laboratory measured MCSVAP

data at each contact including temperature, pressure, amount of water

injected, total cell volume, amount of vapor phase at equilibrium, gas

and oil Z-factors, oil and water saturations, water mole fractions in the

oil and gas phases, amount of oil, gas and water produced, and the

API of the produced oil. The detailed table entries are discussed later.


laboratory measured MCSVAP data. (Default is 1)

■ Viscosity Measurements. The measured viscosities of the initial oil

and of the PVT cell oil and the produced oil for any contact. The


Figure 7-61 shows an example of the data table for entering laboratory

measured MCSVAP data.

Figure 7-61: Laboratory Measured MCSVAP Data

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■ Temperature. Temperature for each contact. This is required input.

■ Pressure. Pressure for each contact. This is required input.

■ H2O Injected. Amount of H2O injected into PVT cell for each contact

in the units specified by Stream Unit. This is required input.

■ Cell Vol(cc). Total cell volume in cc for each contact at equilibrium

after injection of H2O.

■ Cell Vapor. Amount of equilibrium vapor formed for each contact and

then withdrawn in the units specified by Stream Unit.

■ Gas Z-factor. Z-factor of equilibrium vapor formed for each contact.

■ Oil Z-factor. Z-factor of equilibrium cell oil for each contact.

■ Oil Satn. PVT cell oil saturation in fraction at equilibrium for each

contact before withdrawal of vapor.

■ Water Satn. PVT cell liquid water saturation in fraction at equilibrium

for each contact before withdrawal of vapor.

■ H2O M.F./Oil. Mole fraction of H2O in the PVT cell oil phase for each

contact before withdrawal of vapor. This number is calculated only if

the water-in-oil option is activated.

■ H2O M.F./GAS. Mole fraction of H2O in the PVT cell vapor phase for

each contact before withdrawal of vapor. This number is calculated

only if the water-in-oil option is activated.

■ Oil Prod. Amount of oil produced at standard conditions for each

contact in the units specified by Stream Unit.

■ GAS Prod. Amount of gas produced at standard conditions for each

contact in the units specified by Stream Unit.

■ Water Prod. Amount of liquid water produced at standard conditions

for each contact in the units specified by Stream Unit.

■ Prod Oil API. API gravity of produced oil for each contact.

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Figure 7-62 shows the menu for entering viscosity data.

Figure 7-62: Viscosity Data

■ Minimum Viscosity (cp). The minimum value of viscosity used for

plotting viscosity vs. temperature data on logarithmic scale:

where T is absolute temperature. The default value is 0.2. This value

will be internally reset to 0 if any input or calculated viscosity value is

less than the input value.

■ Initial Oil Viscosity(cp). The data table for the measured viscosity of

the initial oil.

■ Cell Oil Viscosity(c). The data table for the measured viscosity of the

PVT cell oil.

■ Produced Oil Viscosity(cp). The data table for the measured viscosity

of the produced oil.

ln ln µ 1 µmin–+( )( ) A B ln T( )+=

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Figure 7-63 shows the data table for entering the measured initial oil

viscosity.

Figure 7-63: Measured Initial Oil Viscosity

■ Temp. Temperature of the measured viscosity. The temperature units

are the same as those defined in the MCSVAP main menu.

■ Pres. Pressure of the measured viscosity. The temperature units are the

same as those defined in the MCSVAP main menu.

■ Viscosity. Measured viscosity (cp) of the initial oil.


the initial oil.

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Figure 7-64 shows the data table for entering the measured PVT cell oil

viscosity. The same data format is also used for produced oil viscosity.

Figure 7-64: Measured PVT Cell Oil Viscosity

■ Contact No. Contact number in the multiple contact steam injection

test.

■ Temp. Temperature of the measured viscosity. The temperature units

are the same as those defined in the MCSVAP main menu.

■ Pres. Pressure of the measured viscosity. The temperature units are the

same as those defined in the MCSVAP main menu.

■ Viscosity. Measured viscosity (cp) of the PVT cell oil.


the PVT cell oil.

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7.3.24 Two Phase Isothermal Flash

This test allows the user to flash a specific composition at a constant

temperature and pressure. The resulting output will be the phase mole

fractions and phase compositions and properties.

The user may choose one of three flash calculation techniques:

■ Successive substition

■ Newton-Raphson

■ Gibbs free energy minimization

Figure 7-61 shows the test parameter input table.

Figure 7-65: Laboratory Measurements




measurements in this test. This is required input. (Default is ˚F)



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including pressure, oil(liquid) phase mole fraction, gas z-factor, oil z-

factor, oil viscosity, gas viscosity, oil density, and gas density. The

detailed table entries are discussed later. The pressure column of thistable is required input.






oil phase compositions (Default is 1)

■ Gas Compositions (GComp). The produced gas phase compositions

in mole fraction at the pressure stages.


gas phase compositions (Default is 1)

Figure 7-62 displays the laboratory data input table.

Figure 7-66: Laboratory Measurements Vertical List

■ Pressure. The pressure at which flashes are to be done. This isrequired input.

■ LMol Frc. Liquid (oil) phase mole fraction at the pressure stages.

■ Gas Z-Fac. The gas z-factors measured at the pressure stages.


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centipoise.

■ VISCg. The gas viscosities measured at the pressure stages, in

centipoise.


■ DENg. The gas densities measured at the pressure stages, in gm/cc.

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Chapter

8

Calculation of Laboratory Procedures

8.1 Introduction

The Run menu contains items for activating laboratory test calculations,

selecting phase behavior calculation methods, and specifying control

parameters for phase behavior calculations. There are six items in the Run

menu:

■ GO

■ Calc Method

■ Psat Tol

■ Flash Tol

■ Expansion Tol

■ Debug

Except for the GO item, a window for entering data will be displayed

when an item is selected. The GO entry is used to activate the phase

behavior calculation. The remaining menu items are used to select

calculation parameters.

The default values for the phase behavior calculation parameters in

DESKTOP-PVT are adequate for most fluid systems. However, for

difficult near-critical fluid systems, some parameters in the saturation

pressure and flash calculations may need to be changed. DESKTOP-PVT

allows the user to change any of these parameters for any of the simulated

tests. The changes in a test will effect only that particular test. Each test

may have its own set of parameters for phase behavior calculations.

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Calculation of Laboratory Procedures DESKTOP-PVT USER’S GUIDE

8.2 Activate Calculation

DESKTOP-PVT calculations are activated by selecting GO. No input data

is required. When the calculation procedure is completed, DESKTOP-PVT

is ready to display the graphic reports for reviewing results. In addition to

activating calculation, DESKTOP-PVT saves the input data in memory

into a file named dtpvt.ini. As discussed in Section 3.2, the input

information stored in dtpvt.ini is loaded into memory when the user

selects the Last Run item in the File menu. The capability to recall the last

run data can be used, for example, to restore input data after a system

crash.

8.3 Selection of Calculation Method

The Calc Method option allows the user to select alternative flash and

viscosity calculation methods. For flash calculations in DESKTOP-PVT,

the user may select the Newton-Raphson method (NEWTON), the method

of accelerated successive-substitution (SS) or the Gibbs energy

minimization method (GIBBS). The Newton-Raphson method is thedefault. The fluid viscosity can be calculated using the Lohrenz, Bray and

Clark (LBC) viscosity correlation (default), a viscosity correlation

described by Reid, Prausnitz and Sherwood (RPS), the Pedersen et al.

(VISPE) viscosity correlation, or the Twu viscosity correlations [TWU1 or

TWU2]. Figure 8-1 is an example of the calculation method selection

window. This menu is displayed when the Calc Method item is selected.

Figure 8-1: Calculation Method Selection Panel

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DESKTOP-PVT USER’S GUIDE Calculation of Laboratory Procedures

8.4 Control Parameters for Saturation Pressure Calculation

The Psat Tol option is used for changing any of the parameters which

control the convergence of the saturation pressure calculation. Figure 8-2

is an example of the selection window for specifying saturation pressure

calculation parameters. This window is displayed when the Psat Tol

option is selected. For each laboratory procedure, seven parameters can be

changed for controlling the convergence of the saturation pressure

calculation.

Figure 8-2: Control Parameters for Saturation Pressure Calculation

■ Max Iter. The maximum number of iterations. (Default is 40)

■ Max Dp. The maximum change in pressure (psia) for an iteration.

(Default is 500)

■ Max Dz. The maximum change in composition for an iteration.

(Default is 0.05)

■ Tol Dp. Convergence tolerance for pressure (psia) change between

iterations. (Default is 0.01)

■ Tol Dz. Convergence tolerance for composition changes between

iterations. (Default is 0.000001)

■ Tol Kval. Convergence tolerance for the heavy component K-value.

The saturation pressure calculation will fail if the heavy component K-

value is greater than 1.0 - tolerance. (Default is 0.00001)

■ Tol DampF. Convergence tolerance for the damping factor of the

pressure and composition changes between iterations. The saturation

pressure calculation will fail if the damping factor is less than the

tolerance. (Default is 0.00001)

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8.5 Control Parameters for Flash Calculation

The user may change any of the parameters which control the

convergence of the flash calculations by selecting Flash Tol. Figure 8-3 is

an example of the selection menu for specifying the flash calculation

parameters. For each laboratory procedure, six parameters can be changed

for controlling the convergence of the flash calculations.

Figure 8-3: Control Parameters for Flash Calculation

■ Max Iter. The maximum number of iterations. (Default is 20)

■ Max Dz. The maximum change in composition and liquid/vapor

fraction for an iteration. (Default is 0.05)

■ Max DLV. The maximum deviation in liquid/vapor fraction from the

limiting values of zero and one for an iteration. (Default is 0.01)

■ Tol Dz. Convergence tolerance for composition and liquid/vapor

changes between iterations. (Default is 0.000001)

■ Tol Kval. Convergence tolerance for the heavy component K-value.

The flash calculation will fail if the heavy component K-value is

greater than 1.0 - tolerance. (Default is 0.00001)

■ Tol DampF. Convergence tolerance for the damping factor of the

composition and liquid/vapor fraction changes between iterations.

The flash calculation will fail if the damping factor is less than the

tolerance. (Default is 0.00001)

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DESKTOP-PVT USER’S GUIDE Calculation of Laboratory Procedures

8.6 Control Parameters for Expansion Tests

The Expansion Tol option is used for improving flash calculation

convergence in constant composition expansion, constant volume

depletion, and differential expansion procedures. The parameters in the

Expansion Tol window are used to control the pressure interval used in

flash calculation for the three laboratory procedures. Figure 8-4 is an

example of Expansion Tol window.

Figure 8-4: Control Parameters for Expansion Test

■ Max Expn Dp. The maximum pressure interval allowed, in psia, in

flash calculation of the expansion tests. If the pressure drop in a

expansion test stage is greater than this interval, additional

intermediate flashs will be performed with this pressure decrement

between the specified pressure stages. (Default is 500)

■ Dp Factor. The factor for reducing the size of a pressure interval when

an intermediate flash fails. If the flash which failed was of size ∆P, the

next intermediate flash calculation will be of size ∆P times this factor.

(Default is 0.1)

■ Min Expn Dp. The minimum pressure interval, in psia, to be used in

flash calculation. If the pressure decrement is less than this interval,

the calculation will be reported as a failure. (Default is 0.001)

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8.7 Debug Output

The user may request additional output of saturation pressure and flash

calculations using the Debug option. This output provides detailed

information for each iteration of the calculations with phase compositions,

z-factors, residuals, and scale factors for each pressure stage. The volume

of output can be quite large, so the user is cautioned to use this option

with discretion. Figure 8-5 is an example of the Debug selection menu. The

default Debug option is OFF, i.e., no additional output for both saturation

pressure and flash calculations. This Debug option can be activated by

entering ON for the corresponding laboratory procedure in the selection

menu.

Figure 8-5: Debug Option Selection Panel

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Chapter

9

Report - Calculation Results

9.1 Introduction

Graphic and tabular reports for the calculated results are created from the

Report menu. At the termination of the phase behavior calculation, the

program is ready to proceed to the Graphics option in the Report menu,

and the results are ready to be examined. In addition, the user can

generate reports by retrieving a database file. See Sections 2.7, 3.6, and 3.7

for more information about database file manipulation. There are fourteen

options in the Report menu.

■ Graphics

■ GraTitle

■ SavGraph

■ GetGraph

■ Table

■ PrtTable

■ SavTable

■ GetTable

■ SaveEOS

■ SaveKval

■ SaveVisc

■ SaveZgrd

■ SavCO2T

■ SaveBOE

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Report - Calculation Results DESKTOP-PVT USER’S GUIDE

9.2 Graphics

The graphic module provides an environment for users to graphically

display calculated results and observation data. This is an interactive

environment that provides a wide range of control over the graphical

presentation of calculated results and observation data. The graphic

module is activated by selecting Graphics from the Report menu.

9.2.1 Selecting Test Procedure for Plot

DESKTOP-PVT simulates a variety of laboratory procedures with the

multiple runs option for all of the laboratory procedures. For the graphic

reports, one set of data for a laboratory procedure is displayed on the

graphic device at a time. The user must select a laboratory procedure for

graphic presentation. The items displayed in the selection window are

identical to the test types specified in the data input procedure. If the

selected laboratory procedure has multiple runs defined, a window with a

list of run numbers will be displayed, and the user is requested to select

the desired run number. To select a test or run, click the button beside the

desired item and then click the OK button. Figure 9-1 is an example of the

laboratory-procedure selection menu for graphic presentation.

Figure 9-1: Selecting Test for Plot

When a laboratory procedure is selected for a graphic session, a Graphic

Menu Bar will be displayed at the bottom of the screen with a picture of

the first plot item automatically displayed on the graphic area. This

selection menu gives a list of plots available for the test and control items.

The selection procedure for the graphics menu depends on the hardware

configuration.

1. Graphic Device with Cursor Device (Mouse):

Point to the desired item by moving the mouse pointer until it is on the

desired item. On some devices, the item will be highlighted. Press MB1

to make the selection.

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DESKTOP-PVT USER’S GUIDE Report - Calculation Results

If the cursor device has buttons in addition to MB1, the use of other

buttons will be context dependent. However, it is generally true that

MB3 and MB4 (if available) can be used to toggle on and off a help

message for the highlighted item. Pressing MB2 will clear away the

menu area so it will not appear on a screen dump. To redisplay the

graphics selection menu area again press MB2.

2. Graphic Device with Only a Keyboard: (Not applicable for X-Window

Terminals)

Point to the desired item by using the left and right arrow keys, and

press the Enter key to select the item. The user may type the first few

letters which are unique enough to distinguish one item from another

to make a selection. Toggle the help message with the ? key.

The exact items of the Graphic Menu Bar are dependent on laboratory

procedures. Figure 9-2 is an example plot with the Graphic Menu Bar.

Usually, the first several items in the menu are the fluid properties

available for review. A selection of these items will immediately display

the corresponding plot on the screen. The solid curve with dots represents

the calculated results. The dots indicate the calculated points. The

observation data points, if present on the same plot, will be shown as cross

marks. If there are too many menu items to fit in one row, >> MORE will

be displayed at both ends of the menu. The >> MORE item indicates

additional items are available for selection. The user can position the

cursor on >> MORE to display additional items for selection.

Figure 9-2: Example Plot with Graphic Menu Bar

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The last two items on the graphics selection menu are CONTRL and EXIT.

The EXIT item allows the user to quit the current graphic session for the

selected laboratory procedure, and return to the previous menu for

selecting another laboratory procedure for graphic reports. The CONTRL

item provides a method for users to manipulate graphic attributes

interactively.

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9.2.2 Interactive Graphic Control

The CONTRL item in the graphics selection menu provides a way for the

user to interactively manipulate the graphic attributes. Any attribute

changes will be immediately reflected on the screen. Only the attributes of

color and line-type, are preserved when the user selects another property

plot. Any changes in color and line type stay effective until the user exits

the graphic report session. Figure 9-3 shows an example plot with the

Control item selected on Graphic Menu Bar.

Figure 9-3: Example Plot with the Control Item Selected on the Graphic MenuBar

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ZOOM

The ZOOM option allows the user to select and display sections of the plot

scene for close detail observations. Several options (Figure 9-4) are

provided to specify the area of interest.

Figure 9-4: Example Plot with Zoom Control Option

■ IXscale. The IXscale option allows the user to specify the horizontal

extent (x-axis) to be zoomed interactively. The graphic cursor will be

overlayed with a vertical line to indicate the area boundary. To define

the desired boundary, position the vertical line at the desired location

of the first boundary and press MB1. Move the vertical line to the

second boundary position and press MB1. The zoomed picture will be

displayed upon specification of both boundaries.

■ IYscale. The IYscale option allows the user to specify the vertical

extent (y-axis) to be zoomed interactively. The graphic cursor will be

overlayed with a horizontal line to indicate the area boundary. To

define the desired boundary, position the horizontal line at the desired

location of the first boundary position and press MB1. Move the

vertical line to the second boundary position and press MB1. The

zoomed picture will be displayed upon specification of both

boundaries.

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■ WINDOW. The WINDOW option allows the user to zoom the

interested rectangular area interactively. When this option is selected,

the following prompt appears below the Menu Bar:

Point to Origin of Window

Position the cursor at the lower left corner of the desired area and

press MB1. The following prompt will appear:

Point to Extent of Window

Expand the window from the lower left to the upper right until the

required window area is achieved and press MB1. The scene will be

redrawn with only the windowed area in the scene.

■ KXscale. The KXscale option allows the user to specify the horizontal

extent (x-axis) to be zoomed through keyboard entry. When KXscale is

selected, the following prompt appears above the graphic area:

Enter scale min & max for x-axis:

The user must enter two values indicating the new x-axis extent. Enter

the minimum value first followed by a space, then enter the maximum

value and press the Enter key.

This feature is most useful when the user wishes to zoom out the

plotting area. The zoomed picture will be displayed upon completing

keyboard entries.

■ KYscale. The KYscale option allows the user to specify the vertical

extent (y-axis) to be zoomed through keyboard entry. When KYscale is

selected, the following prompt appears above the graphic area:

Enter scale min & max for y-axis:

The user must enter two values indicating the new y-axis extent. Enter

the minimum value first followed by a space, then enter the maximum

value and press the Enter key.

This feature is most useful when the user wishes to zoom out the

plotting area. The zoomed picture will be displayed upon completing

keyboard entries.

■ RESTORE. The RESTORE option is used to return the zoomed picture

to its original scales.

■ HIGHER. The HIGHER option returns the user to the previous menu.

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VALUE

The VALUE option provides a means of obtaining X, Y plot location data

from the plot scene. The following prompt will appear:

Select Point [1=Select, 2=Escape]

Position the cursor at the desired location within the scene and press MB1.

The value(s) for the selected point are presented below the menu bar. Two

y-axis values will be shown; however, the value of RY-axis, which shows

the value of the right-hand side y-axis, is immaterial. When the user is

finished, press MB2 to exit the value option.

L_TYPE

The L_TYPE option allows the user to change the line style. The line style

can vary from a solid line to different length line segments. The change

will be effective through the entire graphic report session until a different

line style is selected. To change the line style, select L_TYPE and continue

depressing MB1 until you find the desired line style.

COLOR

The COLOR option allows the user to change the line color. The change

will be effective through the entire graphic report session until a different

line color is selected. To change the color, select color and continue

depressing MB1 until you find the desired color.

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TEXT

The TEXT option allows the user to add text to the display screen at any

location. This feature provides a mechanism for the user to customize his

plots. When the Text option is selected, the following options (Figure 9-5)

will be displayed on the Graphic Menu Bar.

Figure 9-5: Example Plot with Text Edit Option

■ ADD. The ADD option allows the user to add text to the screen. The

following prompt will appear above the graphic area:

Enter Text:

Type in the desired text (up to 80 characters per line) and press the

Enter key. The following prompt will appear:

Enter Scale Factor [Default=1.0]:

This prompt allows you to set the size of the text before it is added to

the screen. A default size will be used if you press Enter; otherwise,

enter the desired size. Then the following prompt will appear:

Select Bottom-Center Point For Text

Position the cursor at the location around which the text should be

centered. Press MB1 and the text will be drawn on the screen.

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NOTE: Up to 50 lines of text can be added to the screen.

■ MOVE. The MOVE option allows the user to change the location of

text. When MOVE is selected, the following prompt appears below the

Menu Bar:

Point To Text With Cursor [1=Select 2-4=Escape]

The selected text will be highlighted and the following menu appears:

OK HIGHER

Select OK if the highlighted text is the appropriate text to be moved.

The following prompt will appear below the Menu Bar:

Select Bottom-Center Point For Text

Position the cursor at the desired new location and press MB1. The text

will be moved to the new location.

■ SCALE. The SCALE option provides a way to change the scale (size)

of text. When SCALE is selected, the following prompt appears below

the Menu Bar:


Position the cursor over the desired text and press MB1. The selected

text will be highlighted (highlighting is yellow on multi-color screens).

Select OK from the next menu to confirm the selection. The following

prompt will appear:

Enter Scale Factor:

Enter the desired new scale factor. For example, with the current text

scale displayed considered 1, a scale factor entry of 2 will double the

text size. An entry of 0.5 will halve the size.

■ DELETE. The DELETE option allows the user to remove user defined

text from the plot. When DELETE is selected, the following prompt

appears below the Menu Bar:


Position the cursor over the desired text and press MB1. The selected

text will be highlighted. Select OK from the menu to confirm the

deletion.

■ REDRAW. To refresh the screen and remove the effects of text being

moved, etc., select the REDRAW option.

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PRINTER

Selection of the PRINTER option will produce output for the PRINTER

device. The output will be saved in a postscript file named psout.ps in the

directory in which the program was started. This file may be

automatically routed by the VIPPRINTER command to the print queue

specified by the environment variable VIPPOST.

REDRAW

To refresh the screen, and remove the effects of graphic attributes being

changed, select the REDRAW option.

HIGHER

This option will return the user to a higher level menu, i.e., to graphic item

selection menu.

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9.3 GraTitle - Running Title for Plot

GraTitle provides a way for users to customize the title of the plot. The

title will be placed on the top of the plot for identification purposes. Upon

selection of this item, a text entry data field will be displayed. The user can

enter up to 50 characters to identify the plot.

NOTE: This option is not available while in Graphics mode. Access this

option prior to selecting Graphics in the Report menu or exit

Graphics and proceed to the GraTitle option.

9.4 SavGraph - Save Graphic Report to File

The calculated results, as well as the corresponding raw input data, can be

saved into a database file for future reference. The SavGraph option is

used to save these data into a database file. Upon selecting SavGraph, a

Filebox pop-up window will be displayed for entry of a filename. The file

extension ".dbf" is suggested, though not restricted, since the file

retrieving mechanism in GetGraph uses this file extension as a default

filter to display a file list for selection. The total length of the filename

allowed is restricted to 12 characters.

NOTE: This option is not available while in Graphics mode. Access this

option prior to selecting Graphics in the Report menu or exit

Graphics and proceed to the SavGraph option.

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9.5 GetGraph - Get Graphic Report from File

The database saved in the SavGraph option can be retrieved by the

GetGraph option. The data retrieved will be ready for a report session, i.e.,

the user can go directly to the Graphics option without invoking the

calculation process. However, since the input data used to generate the

results will be retrieved as well, the data in memory prior to the retrieving

process will be overwritten. The user needs to be aware of this situation to

avoid accidentally destroying input data.

After selecting the GetGraph option, a Filebox pop-up window will be

displayed showing a list of files with the extension ".dbf". To select the

desired file, double-click on the filename.

9.6 Table - Review Tabular Report

After the calculation task is completed, a text output file will be generated.

The Table item provides a way for users to review the calculated results in

table format without leaving the DESKTOP-PVT environment. After

reviewing the result, the user should click the close menu item on the

menu bar of the text window to close the table window. If the user choose

to keep the window and a new calculation run has been performed, the

window content will be updated only if the user hit this Table button

again.

9.7 PrtTable - Print Tabular Report

The table of calculated results can be sent to a printer for hardcopy. No

data entry is required.

9.8 SavTable - Save Tabular Report to File

The table of calculated results can be saved in a text file for future

reference. The SavTable option is used to save these data in a text file.

After selecting SavTable, a Filebox pop-up window will be displayed for

users to enter a filename. The file extension ".tab" is suggested, though not

restricted, since the file retrieving mechanism in GetTable uses this file

extension as a default filter to display a file list for selection. The total

length of the filename is restricted to 12 characters.

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9.9 GetTable - Get Tabular Report from File

The calculated results saved in the SavTable option can be retrieved by the

GetTable option. The data retrieved will be ready for a report session, i.e.,

the user can go directly to the Table item without invoking the calculation

process.

After selecting the GetTable option, a Filebox pop-up window will be

displayed showing a list of files with the extension ".tab". To select the

desired file, double-click on the filename.

9.10 SaveEOS - Save PVT (EOS) Properties to File

The equation-of-state (EOS) file can serve as an interface to other

simulators, e.g., VIP-COMP. When the calculations are completed, an EOS

output file will be created, however, it is not automatically saved unless

this option is selected.

An EOS file contains EOS descriptions for a fluid such as component

names, critical properties and composition, etc. The functions SaveEOS,

Load EOS and Append EOS can be used to transfer the EOS descriptions

of a run to another.

9.11 SaveKval - Save K-value Tables to File

DESKTOP-PVT writes a disk file which contains K-value tables for use in

VIP-ENCORE. The format of the file is syntactically correct for input into

VIP-ENCORE for isothermal tests and into VIP-THERM for thermal tests.

However, the file is not automatically saved until the user tells DESKTOP-

PVT to do so. The SaveKval option is used to save the K-value tables file.

After selecting SaveKval, a Filebox pop-up window will be displayed for

users to enter a filename. The file extension ".kvf" is suggested, though not

restricted. The total length of the filename is restricted to 12 characters.

This file will contain the K-value tables from all constant volume depletion

tests, differential expansion tests, separator tests, and distillation tests.

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9.12 SaveVisc - Save Component Viscosity Tables to File

A component viscosity file is generated if the crude oil viscosity table in

the Distillation Test and one of the Twu viscosity correlations (TWU1 or

TWU2) are specified. This file will contain computed component viscosity

data at the conditions specified in the crude oil viscosity table of the

Distillation Test. The format of the file is syntactically correct for input into

VIP-THERM. However, the file is not automatically saved until the user

instructs DESKTOP-PVT to do so. The SaveVisc option is used to save the

component viscosity file. After selecting SaveVisc, a Filebox pop-up

window will be displayed for users to enter a filename. The file

extension".vsf" is suggested, though not restricted. The total length of the

filename is limited to 12 characters.

9.13 SaveZgrd - Save Composition-vs-Depth Table to File

A Composition-vs-Depth file will be generated if the test of Composition

Variations with Depth (ZGRAD) is selected. This file will contain

computed component compositions in mole fraction at the depths

specified in the ZGRAD test. The format of the file is syntactically correct

for input into VIP-COMP. However, the file is not automatically saved

until the user instructs DESKTOP-PVT to do so. The SaveZgrd option is

used to save the composition file. After selecting SaveZgrd, a Filebox pop-

up window will be displayed for users to enter a filename. The file

extension".zgf" is suggested, though not restricted. The total length of the

filename is limited to 12 characters.

9.14 SaveCO2T - Save CO2-Saturated-Water-Property Table toFile

A file contains the properties of carbon dioxide saturated water will be

generated if the test of solubility of carbon dioxide in water (CO2TAB) is

selected. The format of the file is syntactically correct for input into VIP-

COMP. However, the file is not automatically saved until the user instructs

DESKTOP-PVT to do so. The SaveCO2T option is used to save the

saturated water property file. After selecting SaveCO2T, a Filebox pup-up

window will be displayed for users to enter a filename. The file extension

“.co2” is suggested, though not restricted. The total length of the filename

is limited to 12 characters.

9.15 SaveBOE - Save Black Oil Table to File.

Selecting this option will save an ASCII keyword file that can be included

within a VIP-CORE input file. The file will define the black oil properties

generated from a constant volume depletion test. The default file name is

boetab.inc, but any name with a total length of 12 characters may be used.

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9-176 Landmark - R2003.0

Chapter

10

Tutorial

10.1 Introduction

This tutorial presents a complete step-by-step fluid characterization

example. The data required for entry into the program are presented in

Tables 10-1 to 10-5. The fluid characterization procedure is:

1. Heavy Ends Characterization

2. Default Fluid Predictions

3. Regression on Default Predictions

4. Component Pseudoization

5. Regression on Pseudoized Description

6. Regression on Viscosity data

10.2 Heavy Ends Characterization

The objective of this procedure is to describe the heavy components of the

oil (the Heptanes plus components) using the limited C7+ data. The heavy

ends characterization assumes the C7+ part of the oil can be described as

an extended distribution of components, using a smooth probability

distribution function. This extended description is lumped together into

the desired number of heavy components using mixing rules for critical

properties and molecular weights. In this tutorial example, the heavy ends

will be described using three components.

1. Start DESKTOP-PVT, by typing dtpvt.

2. Select EOS from the Config menu and select Peng-Robinson Equation-

of-State.

3. Turn on the Heavy ends characterization option by selecting Heavy

from the Config menu and choose Yes.

4. Enter the heavy ends parameters by selecting Parameter from the

Heavy menu.

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Tutorial DESKTOP-PVT USER’S GUIDE

a. Enter the Molecular Weight, Specific Gravity, and Mole Fraction

from Table 10-1. The number of heavy components is specified by

giving names for the pseudo-components. The data entry window

can be accessed by selecting Pseudo-Component No. & Name. In

this example, the three pseudo-components will be named HVY1,

HVY2, and HVY3. Add three new lines to input the pseudo-

component names.

NOTE: No data should be entered in the Pending category.

Enter the name of the pseudo components to be created. When

finished, click OK to return to the previous menu.

b. In this example, cut-off molecular weights between heavy

component groups will be specified. Select the option Bracket

M.W. for Grouping. Enter 125.00 as the Bracket No. 1 cut-off, and

300.00 as the Bracket No. 2 cut-off. Click OK to return to the

previous menu.

c. For the option C6 to C7 M.W. Boundary, replace the default value

92 with 90.

d. For this example, default entries for all other options at this level

will be accepted. Click OK to return to the display window.

5. Calculate the pseudo-component properties by choosing Calculate

from the Heavy menu.

6. Inspect the calculated pseudo-component properties by selecting

Review from the Heavy menu. Click OK to return to the display

window.

7. Save these calculated equation-of-state values in a separate file by

selecting Save EOS from the Heavy menu. Name the file HEAVY.EOS.

8. Save the data used to create this heavy ends characterization by

selecting Save from the File menu. Name the file HEAVY.DAT.

The HEAVY.EOS and HEAVY.DAT files are shown in Tables 10-6 and

10-7.

9. Select Heavy from the Config menu and choose No to turn off heavy

ends characterization.

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DESKTOP-PVT USER’S GUIDE Tutorial

10.3 Default Fluid Predictions

This step will combine the results from the heavy ends characterization

with the pure component information to obtain a default fluid

characterization.

1. If the program has been exited, start DESKTOP-PVT and select Peng-

Robinson Equation of State from the Config menu.(as in Steps 1-2 in

the Heavy Ends Characterization Section). If you have not exited the

program, proceed to step 2.

2. Select Test Type from the Config menu. Select Density, Sat Pressure,

Cnst Composition, Cnst Volume as the PVT experiments to be

simulated. Click OK to return to the display window.

3. Select System from the Component menu and choose the pure light

components corresponding to those shown in Table 10-1. Select CO2,

C1, C2, C3, NC4, IC4, NC5, IC5, C6, and click OK. The program will

use the default EOS properties for these components.

4. Load the EOS properties for the heavy components by selecting

Append EOS from the Component menu. Select HEAVY.EOS and click

OK to return to the display window. There will be a delay while the

program retrieves the file.

5. Enter the pure component mole fractions as mole fractions derived

from the Well Stream Mole % figures in Table 10-1 into the Global

reference composition by selecting Composition from the Component

menu.

NOTE: The values for HVY1, HVY2, and HVY3 should already be present.

Click OK to return to the display window. The sum of the mole

fractions should equal unity. If the message Sum of Composition Not

Equal To 1.0, Normalize? (Y/N) is displayed, the values were not

entered correctly. Answer, No to this question and check the input

values. The example below shows what the composition window

should look like.

R2003.0 - Landmark 10-179


6. Enter the data for the individual tests to be simulated; Density,

Constant Composition, Saturation Pressure, and Constant Volume.

a. Select Density from the Tests menu.

Enter the composition, either re-type the overall composition, or

press F2 and load the global reference composition. Click OK to

return to the previous menu. Change density unit to gm/cc (move

mouse point to Density Unit and click MB3, select gm/cc, and click

OK).

NOTE: Before pressing F2, your mouse pointer must be on the entry box.

Enter the temperature of 276˚F. Enter the Laboratory Measured

values for density at 6000 and 4375 psig from Table 10-2. Add as

many columns as necessary to input the data. Check to insure the

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density units are correct. Entries for quantities not measured, such

as Z-factor and Liquid Viscosity in this example, should be left as

zero. Click OK to return to the previous menu.

When finished click OK to return to display window.

b. Select Cnst Composition from the Tests menu.



return to the previous menu. Enter the temperature (276 ˚F) and

Bubble Point Pressure (4375 psig). Set Liquid Volume Fraction

Type to saturation (while the mouse pointer is over the data cell

click MB3 to access the Liquid Volume Fraction Type window.

Click OK to return to the previous menu).

Under Laboratory Measurements enter the Relative Oil Volume

and the Volume of Liquid Phase between the bubble point and the

first depletion level. In continuously decreasing values of pressure,

enter all the data from Table 10-2 and enter the data from pressure

4375 to 3960 psig from Table 10-4. Data entry into the test should

exclude viscosity data. Otherwise property regression would

thereby include viscosity, thus reducing the match of the other

property data. Click OK to return to the previous menu.

When finished click OK to return to the display window.

c. Select Sat Pressure from the Tests menu.



return to the previous menu. Under Laboratory Measurements,

enter the temperature (276 ˚F) and Bubble Pt Pressure (4375 psig).

Click OK to return to the previous menu.


d. Select Cnst Volume from the Tests menu.



return to the previous menu. Enter the temperature (276 ˚F), and

Saturation Pressure (4375 psig).

Next, name the lightest and heaviest components which contain

heptanes plus. In this example, First Heavy Component Name is

HVY1 and the Last Heavy Component Name is HVY3.

Under Laboratory Measurements enter the measured data. Add as

many columns as needed and enter the data for this test from

Tables 10-3 to 10-4. Enter the pressure, the gas z-factor, gas phase

R2003.0 - Landmark 10-181


produced (gas phase produced should be derived from the Gas

Phase Produced Cum. % from Table 10-3), and the oil volume

fraction (oil volume fraction should be derived from the Liquid

Phase Volume % of Volume from Table 10-4). Click OK to return to

the previous menu.


7. Run the program by selecting Go from the Run menu.

8. View the results graphically by selecting Graphics from the Report

menu. The resulting figures should look like:

Figure 10-1 Liquid density from Density Test.

Figure 10-2 Saturation pressure from Saturation Pressure Test.

Figure 10-3 Liquid volume fraction from the Constant

Composition Expansion Test.

Figure 10-4 Cumulative gas produced from the Constant

Volume Depletion Test.

NOTE: For the Constant Composition Expansion, select SLIQ from the

Graphics Menu Bar to display the liquid saturation. For the Constant

Volume Depletion, select GPROD from the Graphics Menu Bar to

display the cumulative gas produced.

9. Save the data for this run by selecting Save from the File menu. Name

the file DEFAULT. DAT.

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10.4 Regression

As shown in Figures 10-1 to 10-4, the default predictions, using the

combined heavy ends characterization and the pure component data,

often does a poor job reproducing the experimental data. Therefore,

regression on some of the equation of state parameters is necessary. Start

with the data in the file, DEFAULT.DAT. We will regress on Omega A and

Omega B for the 3 heavy components and C1, and the binary interaction

parameters for C1 with the 3 heavy components. The order in which the

regression variables are defined is not important. However, please note

that the regression variables are numbered as follows in this tutorial:

1. If the program has been exited, start DESKTOP-PVT, and retrieve the

file, DEFAULT.DAT, by selecting Open from the File menu. If you are

continuing from Section 10.3, skip this step as the data from

DEFAULT.DAT is still loaded in the program.

2. Turn on regression by selecting Regression from the Config menu and

choose Yes.

3. To set the regression variables select Variable from the Regres menu.

a. Select EOS Property and click OK. Enter the number for the

regression variable in the appropriate place in the EOS property

table for regression variables 1-8 (see above table). Click OK to

return to the previous menu.

Regression Variable Number

Omega A-HVY1 1

Omega A-HVY2 2

Omega A-HVY3 3

Omega A-C1 4

Omega B-HVY1 5

Omega B-HVY2 6

Omega B-HVY3 7

Omega B-C1 8

Interact. Param. C1-HVY1 9



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b. Select Binary Coeff and click OK. Enter the numbers for the binary

interaction parameter regression variables in the appropriate

places in the table for variables 9-11 (see above table). Click OK to

return to the previous menu.

c. Select Exit and click OK to return to the display window.

4. From the Regres menu select Limits. Leave the initial value for all the

variables as 1.0. Change the Minimum to 0.7 and the Maximum to 1.3

for all the regression variables. This allows 30% change in each

regression variable.Click OK to return to the display window.

5. Select Control from the Regres menu. Change the Max Number of

Iterations to 20. Click OK to return to the display window.

6. Run the program by selecting Go from the Run menu. It will take

substantially longer to run this regression calculation compared with

the previously calculated default prediction.

7. The results can be viewed graphically by choosing Graphics from the

Report menu. The resulting figures should look like:











8. From the Report menu select Save EOS to save these calculated

equation-of-state values in a separate file. Name this file

REGRESS.EOS.


this file REGRESS.DAT.

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10.5 Component Pseudoization

The twelve component description, with tuned equation of state

parameters, created in the previous sections is too detailed for most

reservoir simulation applications. It is usually necessary to pseudoize, or

"lump", components together to create a phase behavior description with

less components. The goal of such a process is to create an equation of

state characterization which honors all the compositional and PVT data.

The procedure used in this program is based on a method described by

Coats (Ref: SPE 10512). This procedure is performed internally within

DESKTOP-PVT. The only required user specification is how the

components will be lumped. In this tutorial example, the 12 component

description will be lumped down to a 5 component description, and the

components will be grouped as follows:


file REGRESS.DAT by selecting Open from the File menu. If you are

continuing from Section 10.4, skip this step and goto step 3, as the data

from REGRESS.DAT is still loaded in the program.

2. Replace the equation of state characterization with the results from the

previous regression section by selecting Load EOS from the

Component menu and choosing REGRESS.EOS. There will be a delay

while the program processes the file.

3. Turn off regression by selecting Regression from the Config menu and

choosing No.

4. Check to insure that the properties have been loaded properly, by

running the program. Select Go from the Run menu. (This calculation

should be very fast.) View the results be selecting Graphics from the

Report menu. The picture for liquid saturation for the Constant

Composition Expansion should look like Figure 10-7. (You may wish

to save this file by selecting Save from the File menu and name the file

FILENAME.DAT.)

5. Turn pseudoization on by selecting Pseudoization from the Config

menu and choosing Yes.

Pseudo-Components Original Components

P1 CO2, C1

P2 C2, C3, IC4, NC4

P3 IC5, NC5, C6, HVY1

P4 HVY2

P5 HVY3

R2003.0 - Landmark 10-185


6. From the Pseudo menu select Pseudo Name. Click AddRowAfter five

times to add five new rows and fill in the rows with the names of the

new pseudo-components. Click OK to return to the display window.

7. From the Pseudo menu select Parameter.

a. Select Original Composition to enter the composition being

pseudoized. Press F2, select Global Ref Comp and then select OK.


b. Enter the temperature (276 ˚F) and Bubble Pt Pressure (4375 psig).

c. Change Unit Pressure to psig by clicking the box cell with MB1.

Select PSIG and click OK to return to the previous menu.

d. Select Pseudo-Comp P1 Lump. Turn on CO2 and C1 by clicking

the button beside the desired option. Click OK to return to the

previous menu.

e. Repeat the previous step to define each pseudo-component, P2, P3,

etc. (Refer to the table on the previous page.)

f. Click OK to return to the display window.

8. Select Calculate from the Pseudo menu to calculate the pseudo-

component properties.

9. Save the equation of state parameters in the file by selecting Save EOS

from the Pseudo menu. Name the file PSEUDO.EOS.

10. Save the file which created the pseudo components by selecting Save

from the File menu. Name the file CREATPSD.DAT.

11. Replace the existing 12 component equation of state characterization

with the newly created 5 component description by selecting Replace

EOS from the Pseudo menu.

12. By performing the previous step, the global reference composition has

been replaced with its corresponding pseudo-component values. This

can be checked by selecting Composition from the Component menu.

Click OK to return to the display window. All the compositions for the

simulated tests, however, must be reset.

13. Turn pseudoization off, by selecting Pseudoization from the Config,

menu and choosing No.

14. Re-enter the composition data for the individual tests to be simulated.

a. Select Density from the Tests menu. Select composition, press F2

and load the global reference composition. Click OK to return to

the previous menu. All the remaining data should be correct. Click

OK to return to the display window.

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b. Select Cnst Composition from the Tests menu. Select composition,


return to the previous menu. Click OK to return to the display

window.

c. Select Sat Pressure from the Tests menu. Select composition, press

F2 and load the global reference composition. Click OK to return to

the previous menu. Click OK to return to the display window.

d. Select Cnst Volume from the Tests menu. Select composition, press

F2 and load the global reference composition. Click OK to return to

the previous menu. Next, rename the lightest and heaviest

components which contain heptanes plus. The First Heavy

Component Name is now P3 and the Last Heavy Component

Name is P5. Click OK to return to the display window.

15. Run the program by selecting Go from the Run menu.

16. The results can be viewed graphically by selecting Graphics from the

Report menu. The resulting figures should look like:












the file PSEUDO.DAT.

R2003.0 - Landmark 10-187


10.6 Regression After Pseudoization

The match of experimental data for undersaturated conditions is usually

not as good after performing the pseudoization step. In this example,

Figures 10-7 and 10-8 display a much improved data match compared

with Figures 10-11 and 10-12. Again, regression can be used to tune the

equation of state parameters. In this section, regression will be on the

analogous variables used in the previous regression step. These variables

are Omega A and Omega B for the 3 heaviest components (P3, P4, and P5)

and the lightest component (P1), and the binary interaction parameters for

the P1 with the 3 heaviest components. Therefore, the following regression

variables will be used:


file PSEUDO.DAT by selecting Open from the File menu. If you are

continuing from Section 10.5, Component Pseudoization, skip this step

as the data from PSEUDO.DAT is still loaded in the program.

2. From the Config menu select Regression and choose Yes to turn

regression on.

3. Select Variable from the Regres menu to set the regression variables.


regression variable in the appropriate place in the EOS property

table for regression variables 1-8 (refer to the above table).


Omega A-P3 1

Omega A-P4 2

Omega A-P5 3

Omega A-P1 4

Omega B-P3 5

Omega B-P4 6

Omega B-P5 7

Omega B-P1 8

Interact. Param. P1-P3 9



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NOTE: There may already be numbers in this table. These are carried in the

program memory from the regression in Section 10.4. If numbers are

present, they are probably incorrect, and must be reset.


b. Select Binary Coeff and click OK. Enter the numbers for the binary

interaction parameter regression variables in the appropriate

places in the table for variables 9-11 (refer to the table on the

previous page).

NOTE: As above, there may already be numbers in this table. If numbers are

present, they are probably incorrect and must be reset.



4. From the Regres menu select Limits. Leave the initial value for all the

variables as 1.0. Change the Minimum to 0.7 and the Maximum to 1.3

for all the regression variables to allow for 30% changes in each

regression variable. Click OK to return to the display window.

5. From the Regres menu select Control. Change the Max Number Of


6. Run the program by selecting Go from the Run menu. This regression

step should be quicker than the regression step in Section 10.4, as the

equation of state characterization now uses only 5 components

compared with 12 in Section 10.4.


Report menu. Select Cnst Composition and click OK. From the

Graphics Menu Bar select SLIQ to display the liquid saturation. The

picture for liquid saturation for the Constant Composition Expansion

should look like Figure 10-7.

8. From the Report menu select Save EOS to save these calculated

equation-of-state values in a separate file. Name this file

PSDREG.EOS.


this file PSDREG.DAT.

10. Overwrite the equation of state parameters with the results of the

regression step by selecting Load EOS from the Component menu and

select PSDREG.EOS.

R2003.0 - Landmark 10-189


11. Turn regression off by selecting Regression from the Config menu and

choose No.

12. Run this file by selecting Go from the Run menu.

13. The results can be display by selecting Graphics from the Report menu

and should look like:











14. Save this in a separate file by selecting Save from the File menu. Name

this file 5CMPTUNE.DAT

10.7 Regression on Viscosity Data

The final step in data preparation is the calibration of the viscosity model.

One of the parameters which affect the viscosity calculation is the Critical

Compressibility Factors, Zc. In fact, Zc only affects the viscosity

calculation. This allows the viscosity to be tuned separately after all the

other experimental data has been matched. In this example, we will tune

Zc for all 5 pseudo-components. Therefore, the following regression

variables will be used.


Zc Component P1 1

Zc Component P2 2

Zc Component P3 3

Zc Component P4 4

Zc Component P5 5

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file 5CMPTUNE.DAT by selecting Open from the File menu. If you are

continuing from Section 10.6, Regression After Pseudoization, skip

this step as the data from 5CMPTUNE.DAT is still loaded in the

program.

2. Viscosity data is measured in a Constant Composition Expansion

Experiment. Therefore, select Test Type from the Config menu.

Deselect all tests except Cnst Composition by deleting the number

beside the desired item. Click OK to return to the display window.

3. From the Config menu select Regression and choose Yes to turn

regression on.

4. From the Regres menu select Variable to set the regression variables.


regression variable in the appropriate Zc column in the EOS

property table. Note, there may already be numbers in this table in

the columns for Omega A and Omega B. These are carried in the

program memory from the previous regressions. If they are

present, they must be reset to zero. Click OK to return to the

previous menu.

b. Select Binary Coeff and click OK. Zero out any numbers which

may be present. Click OK to return to the previous menu.


5. Select Limits from the Regres menu. Set the Minimum to 0.5 and the

Maximum to 2.0 for all five variables. Click OK to return to the display

window.

6. From the Regres menu select Control. Change the Max Number of


7. Enter the data for the simulated experiment. From the Tests menu

select Cnst Cmposition.

a. Check that the composition has been set by pressing F5 while your

mouse pointer is over the desired item. If the composition is not set

R2003.0 - Landmark 10-191


correctly (see below), then copy the global reference composition

by pressing F2. Click OK to return to the display window.

b. Check that the temperature is set to 276 ˚F and the bubble point

pressure is 4375 psig.

c. Select Laboratory Measurements. Erase all the present data by

pressing DeleteRow until all the Pending Row is the only row left.

Add 18 new rows by pressing AddRowAfter or AddRowBefore.

Enter the pressures and oil viscosities from Table 10-5. Click OK to

return to the previous menu. Click OK to return to the display

window.

8. From the Run menu select Go to run the program


Report menu. Select Cnst Composition and click OK. From the

Graphics Menu Bar select VISCo to display the oil viscosity. The

picture for oil viscosity for the Constant Composition Expansion

should look like Figure 10-17.

10. Select Save EOS from the Report menu to save the calculated equation-

of-state values in a separate file. Name this file VISTUNE.EOS. This

will be the PVT file containing the equation of state parameters for

input to a reservoir simulator.


this file VISTUNE.DAT.

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Table 10-1: Compositional Data

Component Name Well Stream: Mole %

Carbon Dioxide 5.84

Methane 50.43

Ethane 9.65

Propane 8.75

iso-Butane 2.36

n-Butane 3.53

iso-Pentane 1.58

n-Pentane 1.37

Hexanes 2.29

Heptanes Plus 14.2

Heptanes Plus - Molecular Weight 183.

Heptanes Plus - Specific Gravity 0.8345

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Table 10-2: Pressure-Volume Relations of Reservoir Fluid at 276 ˚F(Constant Composition Expansion)

Pressure(PSIG)

RelativeVolume (Used in) Density

gm/cc (Used in)

6000 0.92 CCEXP 0.4924 CCEXP

5000 0.9386 CCEXP

4500 0.9909 CCEXP

4375 (Bubble Pt) 1.0000 CCEXP 0.4530 CCEXP

4328 1.0052 CCEXP

4267 1.0117 CCEXP

4230 1.0158 CCEXP

4059 1.0368 CCEXP

3709 1.0883 CCEXP

3408 1.1472 CCEXP

2688 1.3595 CCEXP

1962 1.7834 CCEXP

1271 2.7310 CCEXP

951 3.6866 CCEXP

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Table 10-3: Depletion Study at 276 ˚F

Pressure(PSIG)

M.W.Heptanes

Plus

Gas Z-Factor Gas PhaseProd. (Cum %) Used In

4375 183 Not Avail. 0 CVDEP

3700 138 0.893 8.753 CVDEP

3000 129 0.858 19.629 CVDEP

2200 120 0.860 35.179 CVDEP

1400 115 0.892 52.727 CVDEP

700 116 0.939 69.232 CVDEP

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Table 10-4: Volume of Liquid Phase at 276 ˚F

Pressure(PSIG)

Liquid Phase Volume% of Volume at Bubble Pt Used In

4375 (Bubble Pt) 100.00 CCEXP

4300 65.1 CCEXP

4150 57.0 CCEXP

3960 53.0 CCEXP

3700 (First Deple-

tion Level)

50.1 CVDEP

3000 45.0 CVDEP

2200 41.4 CVDEP

1400 37.6 CVDEP

700 33.3 CVDEP

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Table 10-5: Viscosity at 276 ˚F From a CCEXP Experiment

Pressure(PSIG)

Liquid Viscosity (Centipoise)

6200 0.106

5780 0.102

5415 0.098

4980 0.095

4620 0.093

4375 (Bubble Pt) 0.091

4225 0.099

4100 0.101

3900 0.105

3700 0.109

3400 0.114

3000 0.125

2600 0.137

2200 0.153

1800 0.172

1400 0.199

1000 0.231

700 0.260

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Table 10-6: HEAVY.EOS File

EOS PR

COMPONENTS

HVY1 HVY2 HVY3

PROPERTIES

COMP MW TC PC ZC ACENTRIC OMEGAA OMEGAB

HVY1 107.94 570.43 424.66 0.26346 0.30783 X X

HVY2 188.08 805.44 278.66 0.24256 0.52090 X X

HVY3 397.52 1226.32 147.94 0.20137 1.09954 X X

DJK C1

HVY1 0.037935

HVY2 0.049365

HVY3 0.065926

ENDEOS

C

C PLUS FRACTION PSEUDO COMPONENT COMPOSITIONS

C

COMPOSITION

0.044272 0.084232 0.013497

10-198 Landmark - R2003.0


Table 10-7: HEAVY.DAT File

SPLIT

MWPLUS GPLUS ZPLUS NG MWGRP

183.00 0.8345 0.1420 3 125.00 300.00

PROPERTY CORRELATION SIMULATION

TC RIAZI-DAUBERT

PC RIAZI-DAUBERT

ACENTRIC EDMISTER

ZC RIAZI-DAUBERT

CONMWI

MWC6C7 90.00

MWINC 12.000

END

R2003.0 - Landmark 10-199


10-200 Landmark - R2003.0


R2003.0 - Landmark 10-201


10-202 Landmark - R2003.0


R2003.0 - Landmark 10-203


10-204 Landmark - R2003.0

Appendix

A

References

1. Wiebe, R.: “The Binary System Carbon Dioxide-Water Under

Pressure,” Chemical Reviews, 29 (1941) 475-481.

2. Malinin, S.D. and Savelyeva, N.I.: “The Solubility of CO2 in NaCl and

CaCl2 Solutions at 25, 50, and 75˚ Under Elevated CO2 Pressures,”

Geochemistry International, (1972) 410-418.

3. Malinin, S.D. and Kurovskaya, N.A.: “Solubility of CO2 in Chloride

Solutions at Elevated Temperatures and CO2 Pressures,” GeochemistryInternational, (1975) 199-201.

4. McRee, B.C.: “CO2: How It Works, Where It Works,” PetroleumEngineers, (Nov. 1977) 52-63.

5. Rowe, A.M. and Chou, J.C.: “Pressure-Volume-Temperature-

Concentration Relation of Aqueous NaCl Solutions,” J. of Chemical andEngineering Data, Vol. 15, No. 1 (1970) 61-66.

6. Parkinson, W.J. and De Nevers, N.: “Partial Model Volume of Carbon

Dioxide in Water Solutions,” I & EC Fundamentals, Vol. 8, No. 4 (Nov.

1969)709-713.

7. Sayegh, S.G. and Najman, J.: “Phase Behavior Measurements of CO2-

SO2- Brine Mixtures,” The Canadian Journal of Chemical Engineering, Vol.

65 (April 1987) 314-320.

8. Osif, T.L.: “The Effects of Salt, Gas, Temperature, and Pressure on the

Compressibility of Water,” SPE Reservoir Engineering, Vol. 3, No. 1 (Feb.

1988) 175-181.

9. Kestin, J., Khalifa, H.E., Abe, Y, Grimes, C.E., Sookiazian, H. and

Wakeham, W.A.: “Effect of Pressure on the Viscosity of Aqueous NaCl

Solutions in the Temperature Range 20-150 ˚C”, J. of Chemical andEngineering Data, Vol. 23, No. 4 (1978) 328-336.

10. Whitson, C. H. and Torp, S. B.: “Evaluating Constant Volume

Depletion Data”, JPT, (Mar., 1983), 610-620.

11. Coats, K. H.: “Simulation of Gas Condensate Reservoir Performance”,

JPT, (Oct., 1985), 1870-1886.

R2003.0 - Landmark A-205


A-206 Landmark - R2003.0

❖

000000Subject Index

Aaccelerated successive-substitution 8-156

acentric factor

entry in property table 5-36

plotting 6-57

use in heavy fraction 6-56

annotation

adding to a plot 9-169

API gravity data

entering for distillation test 7-122

appending an EOS file 5-34

Bbatch data file

definition of 2-16

batch mode 2-5

bibliography xviii, A-205

binary coefficients

specification of 5-38

binary exponents

defining 5-38

binary interaction coefficients

entering for nonlinear regression 6-64, 6-65

how to define 4-25

plotting 6-57

use in mixing rules 5-38

binary interaction coefficients of H2O

how to specify for thermal 4-28

blend API gravity data


boiling point temperature


plotting 6-57

bracket molecular weights 6-53

bubble point pressure 4-26, 7-85

of pseudo components 6-60

oil-water 7-112

Ccalculation

how activated 8-156

how to invoke 2-16

of phase envelope 4-26

calculation method

selecting 8-156

carbon dioxide

saturated water properties 5-44

carbon dioxide saturated water

entering property correlations 6-67

saving data in file 9-175

carbon dioxide solubility 5-44

how calculated 5-45

Cavett correlation 6-55

click and drag

definition of xvii

CO2 saturated water 4-27

component K-value


Component menu

Append EOS option 5-34

Load EOS option 5-34

overview of 5-31

System option 5-31

User option 5-32

Volatile option 5-33

components

setting default 5-31

user-defined 5-32

volatile 5-33

composition 4-30

loading from another test 5-33


composition expansion procedure 4-26

composition source

defining 4-27

composition specification 4-29

composition variation test 4-29

composition variations with depth 4-27

R2003.0 - Landmark Subject-207

Subject DESKTOP-PVT USER’S GUIDE

compressibility

of water, how calculated 5-48

Config menu

Binary Coeff option 4-25, 5-38

Composition Sor option 4-27, 6-58

EOS option 4-24

Heavy option 4-29

overview of 4-23

Pseudoization option 4-27

Regression option 4-27

Run Sequence option 4-29

Run-Time Compos option 4-29

System Info option 4-24

Test Type option 4-25

Thermal option 4-28

Water-In-Oil option 4-29

confirmation dialog

how to use 2-12

constant composition expansion test 4-29

constant composition test 7-88

constant volume depletion procedure 4-26, 7-92

constant volume depletion test 4-29

Control key combinations xviii

correlation

Cavett 6-55

Edmister 6-56

Kesler-Lee 6-55

Riazi-Daubert 6-55

Riedel-Pitzer 6-55

use to calculate EOS 6-55

Whitson 6-56

critical pressure


plotting 6-57


critical temperature


plotting 6-57

critical z-factor


plotting 6-57

crude viscosity data


cursor movement control xviii

Ddat file extension 2-16

data

generating table of 9-173

printing a table of 9-173

retrieving from database 9-173

retrieving tabular data 9-174

saving table of 9-173

saving to a database 9-172

data entry

general guidelines 2-7

data file

how to open new 3-20

data set

adding descriptive text 4-24

database file

definition of 2-17

how to open 3-20

saving 3-20

debugging information 8-160

defaults

component 5-31

density

laboratory procedures 4-26

liquid 7-81

density correlation 5-45

entering for nonlinear regression 6-67

density units

use as input in test procedures 7-76

derivative calculation

in regression 6-71

DESKTOP-PVT

batch mode 2-5

how to exit 3-21

Overview 1-1

starting the program 2-5

dew point pressure 7-85


differential expansion procedure 4-26

differential expansion test 4-29, 7-99

differential liberation test 7-99

differential vaporization test 7-99

Display Window

description of 2-6

distillate API gravity


distillation curve

entering 7-116

distillation table


distillation test 4-26, 7-114

dtpvt.ini file 3-19, 3-21

Subject-208 Landmark - R2003.0

DESKTOP-PVT USER’S GUIDE Subject

EEdmister correlation 6-56

enthalpy 4-26

gas, how to specify 5-39

of a gas mixture 7-107

of a liquid mixture 7-109

enthalpy units


EOS data file

appending 5-34

definition of 2-17

opening and loading 5-34

EOS parameters

calculation for heavy fraction 6-55

equation-of-state

calculation in heavy fraction 6-54

how to specify 4-24

saving calculations 9-174

use in DESKTOP-PVT 1-2

use in pseudoization 6-58

equation-of-state data file

definition of 2-17

equation-of-state parameters

appending for pseudo components 6-61

appending to a file 6-57


overwriting 6-57

overwriting for pseudo components 6-61

review in table format 6-60

review in tabular form 6-57

saving 6-57

saving for pseudo components 6-60

FFile Box Pop-up

how to use 2-8

File menu

Exit option 3-21

Last Run option 3-19

Load Database option 2-17, 3-20

New option 3-20

Open option 2-16, 3-20

overview of 3-19

Save Database option 2-17, 3-20

Save option 2-16, 3-20

file types

summary of 2-16

first single carbon number

entry of 6-52

flash calculation convergence

improving 8-159

flash calculations

control parameters for 8-158

flash expansion test 7-88

flash liberation test 7-88

flash vaporization test 7-88

fluid characterization

tutorial on 10-179

fluid composition

loading from another test 5-33


requirements for tests 7-74

unpseudoized 4-29

Fluid menu

Binary Coeff option 4-25, 5-38

Binary Exponent option 5-38

CO2TAB Correlation option 5-44

Gas Enthalpy option 5-39

K-Value Correlation option 5-44

overview of 5-35

Pedersen Visc option 5-42

Property option 5-36

fluid properties


specifying 5-36

fluid property table 5-36

fluid temperature


formation volume factor

calculation for CO2 saturated water 5-47

fraction characterization


fugacity coefficient 7-111

function keys (F1, F2, etc.) xviii

Ggamma distribution function 6-50

alpha parameter 6-53

for heavy fractions 6-50

gas compressibility factor 4-26, 7-79

gas enthalpy

how to specify 5-39

of a mixture 7-107

gas-oil ratio units


Gibbs method 8-156



global reference composition 5-33

graphic analysis

of heavy fraction 6-57

graphic attributes

setting 9-165

graphic module 9-162

HH2O Binary Coef menu

display of 5-38

H2O equation-of-state properties

how loaded 4-28

hardware/software requirements 1-3

heavy ends characterization

tutorial on 10-177

heavy fraction

review results 6-57

heavy fraction characterization 6-49

how to activate 4-29

use in generating EOS data 2-17

heavy fraction properties

entry of 6-50

Heavy function

overview 6-49

Heavy menu


Calculate option 6-56

Graphics option 6-57

overview 6-50

Parameter option 6-50

Replace EOS option 6-57

Review option 6-57

Save EOS option 6-57

hydrocarbon composition

variation with depth 7-137

Iideal gas state 5-39

input data

recalling from last simulation 3-19

input data file 2-16

opening and reading 3-20

item selection panel

how to use 2-10, 2-11

iteration

for nonlinear regression 6-70

KKesler-Lee correlation 6-55

K-value correlation

specifying for nonlinear regression 6-66

K-values


how computed 5-44

saving tables of 9-174

Llaboratory distillation test 7-114

laboratory procedures 4-29

bubble point pressure 4-26

CO2 saturated water 4-27

common input data for 7-74

composition expansion 4-26

composition variation 4-27

constant volume depletion 4-26

density 4-26

differential expansion 4-26

distillation test 4-26

enthalpy 4-26

gas compressibility factor 4-26

multiple contact vaporization 4-26

phase envelope calculation 4-26

saturation pressure 4-26

separators 4-26

specifying other conditions 7-75

steam distillation 4-26

steam vaporization 4-27

swelling test 4-26

use in simulation data 1-2

vapor pressure 4-26

vaporization test 4-26

viscosity 4-26

water properties 4-26

laboratory separator test

calculation of 7-132

laboratory tests 4-29

last single carbon number

entry of 6-53

line color

in plots 9-168

line style

in plots 9-168

liquid density 7-81



liquid enthalpy

of a mixture 7-109

liquid water properties 7-111

list entry panel

how to use 2-13, 2-14

Lohrenz, Bray and Clark 8-156

Lohrenz-Bray-Clark correlation

alternatives to 5-42

Mmanual

overview of xv

MB1, MB2, etc.

definition of xvi

Menu Bar

description of 2-6

menu options

how to select 2-7

mixing rules

parameters used in 5-38

mole fraction

calculation of 6-50


entry of 6-52

how to specify 4-29

plotting 6-57

review in table format 6-60

review in tabular format 6-57

mole fraction distribution

entry of 6-52

molecular weight

calculation of 6-50



entry of 6-52

minimum expected in heavy fraction 6-54

plotting 6-57

molecular weight boundary

in heavy fraction 6-54

molecular weight interval

in heavy fraction 6-54

mouse buttons

how to use xvi

multiple contact steam vaporization test

thermal properties for 4-28

multiple contact vaporization test 4-26, 7-102

multistage separator

modeling of 7-130

Nnew data file

how to open 3-20

Newton-Raphson method 8-156

nonlinear regression 6-49

entering control data 6-70

entering variables for 6-62

package included 1-1

tutorial on 10-183

nonlinear regression calculation

overview of 6-62

non-volumetric observed data 6-71

Oobserved data

use in regression 6-71

oil composition

water-free 7-112

Omega A,B


opening a database file 3-20

output

quantity for regression 6-70

output file

definition of 2-18

PParachor


Parkinson and De Nevers 5-47

Passut-Danner ideal gas state 5-39

Pedersen method 8-156

Pedersen viscosity correlation

how to specify 5-42

phase envelope

calculation of 7-136

phase envelope calculation 4-26, 7-104



plotting

annotation of plots 9-169

changing the line color 9-168

changing the line style 9-168

customized title 9-172

obtaining X, Y plot location data 9-168

retrieving data 9-173

saving data 9-172

selecting lab procedures for 9-162

zooming the plot 9-166

pop-up windows

summary of 2-8

PostScript output file

definition of 2-18

predictive mode


pressure

critical of fluids 5-36

pressure units

definition of 5-36


use as input in test procedures 7-76, 7-77

pressure-volume relations test 7-88

printer

setting up output 2-18

PRINTER option 2-18

printing

table of data 9-173

properties

specifying for fluids 5-36

property table

entering for fluids 5-36

pseudo components 6-49

entering data for 6-59

entering number and name 6-58

specifying for heavy fractions 6-53

Pseudo function

overview 6-49

Pseudo menu


Calculate option 6-58, 6-60

overview of 6-58

Parameter option 6-59

Pseudo Name option 6-58

Replace EOS option 6-61

Review option 6-60

Save EOS option 6-60

pseudo-critical temperature


pseudoization

detail discussion/activating 4-27

overview of 6-58

regression after

tutorial on 10-188

tutorial on 10-185

use in DESKTOP-VIP 1-2

Qquitting DESKTOP-PVT 3-21

Rreference temperature


Regres menu

Control option 6-70

Limits option 6-69

overview of 6-62

Variable option 6-62

regression

tutorial on 10-183

regression function

activating 4-27

regression variables

entering 6-67


setting initial value of 6-69

regression weight factors


Reid, Prausnitz and Sherwood 8-156

Report menu

GetGraph option 2-17, 9-173

GetTable option 9-174

Graphics option 9-162

GraTitle option 9-172

overview of 9-161

PrtTable 9-173

PrtTable option 2-18

SaveCO2T option 9-175

SaveEOS option 9-174

SaveKval option 9-174

SaveVisc option 9-175

SaveZgrd option 9-175

SavGraph option 2-17, 9-172

SavTable option 9-173

Table option 2-18, 9-173



residue API gravity


results

displaying 9-162

results of calculation

how to view 2-16

Riazi-Daubert correlation 6-55

Riedel-Pitzer correlation 6-55

Rowe and Chou 5-47

Run menu

Calc Method option 8-156

Debug option 8-160

Expansion Tol option 8-159

Flash Tol option 8-158

Go option 8-156

overview of 8-155

Psat Tol option 8-157

run numbers 4-29

run sequence 4-30

how to specify 4-29

run-time composition option


Ssalinity effects

adjusting 5-47

saturation pressure 4-26


use in test procedures 7-85

saturation pressure calculation

controlling convergence 8-157


saturation pressure type


saving a database file 3-20

saving current data 3-20

Sayegh and Najman 5-47

SCN equation-of-state parameters 6-56

screen layout 2-6

search vector length

initializing for regression 6-70

separator, multistage

modeling of 7-130

separators 4-26

solubility

CO2, calculation of 5-45

specific gravity


entry of 6-52

plotting 6-57

starting the program 2-5

steam distillation 4-26

steam distillation test

overview of data requirements 7-127


steam vaporization 4-27

steam vaporization test

overview of 7-145

sum-of-square

reduction in 6-71

swelling test 4-29, 7-97

swelling test procedure 4-26

system information

adding 4-24

Ttable entry panel

how to use 2-15

table look-up

use to calculate EOS 6-55

temperature

boiling, entry of 5-37

critical, of fluids 5-36

reference, entry of 5-37

temperature units

definition of 5-36





Test menu

Cnst Composition option 7-88

Cnst Volume option 7-92

Density option 7-81

Differential option 7-99

Distillation option 7-114

Gas Enthalpy option 7-107

Liquid Enthalpy option 7-109

Multi-Contact option 7-102

overview of 7-73

Phas Envlop option 7-104

Phas Envlop/Full option 7-136

Sat Pressure option 7-85

Sat Pressure/H20 option 7-112

Separator/No Reg option 7-130

Separator/Reg option 7-132

Steam Distillation option 7-127

Steam Vaporizatn option 7-145

Swelling option 7-97

Vapor Pressure option 7-83

Viscosity option 7-87

Water Property option 7-111

Z-Factor option 7-79

ZGRAD option 7-137

test procedures

specifying the type of 4-25

text

adding to a plot 9-169

text-entry window

how to use 2-9

thermal option


title

customizing for a plot 9-172

tutorials

fluid characterization 10-179

heavy ends characterization 10-177

nonlinear regression 10-183

overview of 10-177

pseudoization 10-185

regression after pseudoization 10-188

regression on viscosity data 10-190

Twu viscosity correlation 8-156

Uunpseudoized fluid compositions

how to specify 4-29

user-defined components 5-32

Vvapor pressure 4-26, 7-83

vaporization test 4-26

VIPPOST variable 2-18

VIPPSOUT variable 2-18

VIP-THERM

activating Thermal option in PVT 4-28

defining volatile components 5-33

water-in-oil option for 4-29

viscosity 4-26


of fluid mixture 7-87

of water,calculation of 5-48

regression tutorial 10-190


viscosity correlation 8-156

specifying 5-42

use in pseudoization 6-58

viscosity data


volume shift parameter



how computed 5-38

plotting 6-57


Wwater compressibility

how calculated 5-48

water formation volume factor 5-45

water properties 4-26, 7-111

water viscosity

how calculated 5-48

water-free oil composition 7-112

water-in-oil option


Watson characterization factor

for heavy fraction 6-54

use of 6-51

weight factor


weight fraction

entry of 6-52

plotting 6-57

Whitson correlation 6-56



Zz-factor 7-79

critical 5-36

plotting 6-57

zoom

plots 9-166


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