that the feed pool resid content is computed elsewhere by recursion ofpooling streams and treats resid content as a property of the feed.

DATA FOR DELTA-BASED MODELS

The data used in the delta-based model must be developed by the userto reflect the parameters and their effect on the process yield. In thecontext of the refinery streams, only streams properties that are generallymeasured can be considered. For example, the cat reformer yield can berelated to the naphthene plus aromatic content of the feed if the refineryhas reference data to correlate the cat reformer yield at a given severityvs. (naphthene plus aromatic) content of the feed.

Care has to be taken that the shift vectors do not extrapolate databeyond the range for which these were developed. Also, as the shiftvectors can take either positive or negative values, these should bedeclared free in the BOUND section of the LP model.

ATMOSPHERIC CRUDE DISTILLATIONAND VDU MODELING

LP models for crude and vacuum distillation can be constructed exactlyin the same manner as done in the case of other process unit submodels.Most refineries may have more than one crude unit and may be processingmore than one crude oil. Also, a crude unit may operate in more than onemode; for example, one crude unit mode may maximize the production ofnaphtha and another may maximize the production of kerosene. It is,therefore, convenient to enter all data on yields and properties of thevarious cuts from different crude oils and crude and vacuum distillationunits present and their utility consumption, pooling of various cuts fromcrude and vacuum units in three tables for easy updating.

ASSAYS TABLE

Data in the form of yields of various crude on different CDUs andproperties of cut produced is entered in a single table, the Assay Table(Table 13-17). This table does not directly generate any matrix but only

Previous Page

provides data for crude and vacuum units modeling. The yields in theAssay Table could be either in volume or weight units. The columnnames in the table are three character operation modes5 of various crudecolumns. There are four type of rows in this table.

The first set of rows is used to provide cut yields. The row names areVBALxxx, WBALxxx, or DBAL.xxx. VBAL and WBAL indicatea volume or weight basis yield. The tag xxx is the name of the cut producedfrom the distillation. The DBAL row defines a cut being produced not onthe crude distillation unit but from a downstream unit. Examples of suchcuts in the refinery are numerous. For example, a crude distillationcolumn may produce a broad cut containing naphtha and some kerosene.This cut is further fractionated into naphtha and kerosene in a down-stream naphtha fractionation column. In this case, as naphtha is not beingactually produced on the crude column but somewhere else, it will berepresented in the Assay Table by the DBAL row instead of the VBAL row.

The second set of rows may be used to specify atmospheric or vacuumunit utility consumption that is crude specific. The row name for this setis in the form of UATMxxx or UVACxxx, where xxx is the utilityconsumed.

A third set of rows may be used to specify atmospheric or vacuum unitcapacity consumption values that are crude specific. The row name forthis set is CCAPATM or CCAPVAC, and the entries for each crude arethe units of capacity consumed per unit charged to the atmospheric andvacuum towers.

The fourth set of rows is used to provide cut properties. The row namesfor this set are Ipppxxx where ppp is the property (SPG, SUL, API, etc.)and xxx is the cut name. The first letter, I, indicates that this is propertydata. The second through fourth characters of the row name identify theproperty, while the final three characters identify the process stream towhich this property applies:

ISPGLNl Specific gravity of LNl.ISULW26 Sulfur content of cut W26.IVBIL26 Viscosity blend index of cut L26.

The coefficients in the I rows are the values of the specific property ofa specified stream. I rows do not themselves appear in the matrix. The LPmodel uses this data by multiplying, for example, ISPGLNl, withvolumes in row VBALLNl and placing the result in recursion rowRSPGLNl for computing the specific gravity of a blend of streams.

Table 13-17Crude Assays

5CDUB5K

5CDUB5N

4CDUB4K

4CDUB4N

3CDUB3K

3CDUB3N

2CDUB2K

2CDUB2N

1CDUB1K

1CDUB1N

5CDUA5K

5CDUA5N

4CDUA4K

4CDUA4N

3CDUA3K

3CDUA3N

2CDUA2K

2CDUA2N

1CDUA1K

1CDUA1NMODE

0.00600.01510.0465

0.0734

0.1911

0.1419

0.5261

1

1

0.1613

0.00600.01510.0465

0.0952

0.1693

0.1419

0.5261

1

1

0.1613

0.01060.00650.07910.0625

0.1409

0.0677

0.07890.1389

0.1370

0.2779

1

1

1

0.1753

0.01060.00650.07910.08430.1192

0.0677

0.0789

0.1389

0.1370

0.2779

1

1

1

0.1753

0.00600.01510.0381

0.0878

0.1950

0.2343

0.01380.4099

1

1

1

0.1963

0.00600.01510.0381

0.1026

0.1802

0.2343

0.01380.4099

1

1

1

0.1963

0.00600.01510.0445

0.0586

0.23360.1162

0.5261

1

1

0.1613

0.00600.01510.0445

0.0912

0.2010

0.1162

0.5261

1

1

0.1613

0.00710.01290.0494

0.0774

0.1891

0.1310

0.5330

1

1

0.1613

0.00710.01290.0494

0.1001

0.1664

0.1310

0.5330

1

1

0.1613

0.00510.01940.0714

0.0745

0.1820

0.1323

0.5154

1

1

0.1613

0.00510.01940.0714

0.0964

0.1601

0.1323

0.5154

1

1

0.1613

0.00560.01480.10630.0585

0.1402

0.0626

0.07260.1243

0.1263

0.2887

1

1

1

0.1753

0.00560.01480.10630.08740.1114

0.0626

0.07260.1243

0.1263

0.2887

1

1

1

0.1753

0.00490.02050.0616

0.0873

0.1889

0.2138

0.01290.4100

1

1

1

0.1963

0.00490.02050.0616

0.1032

0.1730

0.2138

0.01290.4100

1

1

1

0.1963

0.00490.02050.0694

0.0565

0.2327

0.1004

0.5154

1

1

0.1613

0.00490.02050.0694

0.0894

0.1999

0.1004

0.5154

1

1

0.1613

0.00510.01940.0744

0.0765

0.1870

0.1153

0.5224

1

1

0.1613

0.00510.01940.0744

0.0984

0.1651

0.1153

0.5224

1

1

0.1613

Atmos Unit Yields

CDU Off Gas (C3 -)CDU C3/C4CDU LSRs4AMSRCDU HSRCDU Arab HSR for KRUCDU Bah HSR for KRUCDU KeroseneCDU Arab Ker for KRUCDU Bah Ker for KRUCDU Light DsI4A CDU Med/Int DsIAtmos ResidHeavy DieselsCDU Vac Resids

Total Yield

CDU CAPACITY

VDU CAPACITY

GAS MSCF/BBL CRUDE

VBALGAlVBALC41VBALLSlVBALMN4VBALHNlVBALHA4VBALHB4VBALKNlVBALKAlVBALKBlVBALDNlVBALMI4VBALRAlVBALHD3VBALVA3

CCAPATM

CCAPVAC

UATMFUL

DEFERRED CUT YIELDS (Vacuum units)

1 VDU Normal Mode

0.05220.26630.2075

0.00110.03700.32320.02420.1407

0.05220.26630.2075

0.00110.03700.32320.02420.1407

0.05450.27090.2076

0.00110.03740.32950.02450.1404

0.05450.27090.2076

0.00110.03740.32950.02450.1404

0.04460.24990.2208

0.03120.30510.01910.1601

0.0446

0.2499

0.2208

0.03120.30510.01910.1601

0.04620.25440.2218

0.03220.31130.01990.1591

0.04620.25440.2218

0.03220.31130.01990.1591

IVDU WGO ON CRUDEIVDU DGO ON CRUDEIVDU VR ON CRUDE

1 VDU Asphalt Operation

IVDU LWGO ON CRUDEIVDU WGO ON CRUDEIVDU DGO ON CRUDEIVDU BSGO ON CRUDEIVDU ASP ON CRUDE

1 VDU BSGO PRODUCTION

IVDU WGO ON CRUDEIVDU DGO ON CRUDEIVDU BSGO ON CRUDEIVDU VACRES ON CRUDE

DBALWIlDBALLIlDBALVIl

DBALLWlDBALW21DBALL21DBALBSlDBALASl

DBALW31DBALL31DBALBS3DBALV31

Table 13-17Continued

5CDUB5K

5CDUB5N

4CDUB4K

4CDUB4N

3CDUB3K

3CDUB3N

2CDUB2K

2CDUB2N

1CDUB1K

1CDUB1N

5CDUA5K

5CDUA5N

4CDUA4K

4CDUA4N

3CDUA3K

3CDUA3N

2CDUA2K

2CDUA2N

1CDUA1K

1CDUA1NMODE

0.00320.14200.23070.1502

0.00320.14220.24160.1391

0.00260.13510.23380.1545

0.00320.14200.23070.1502

0.00320.14220.24160.1391

0.00260.13510.23380.1545

0.10780.1701

0.09000.1879

0.10780.1701

0.0900

0.1879

0.00000.04070.21260.1566

0.02790.21160.1704

0.00000.04070.21260.1566

0.02790.21160.1704

0.00320.14200.23070.1502

0.00260.13510.23380.1545

0.00320.14200.23070.1502

0.00260.13510.23380.1545

0.00320.14760.23270.1495

0.00210.14270.23370.1544

0.00320.14760.23270.1495

0.00210.14270.23370.1544

0.00310.12690.22070.1647

0.00260.12120.22070.1709

0.00310.12690.22070.1647

0.00260.12120.22070.1709

0.10550.1833

0.08380.2049

0.1055

0.1833

0.0838

0.2049

0.00330.02770.20850.1705

0.0232

0.1987

0.1881

0.00330.02770.20850.1705

0.0232

0.1987

0.1881

0.5154

0.00310.12690.22070.1647

0.00260.12120.22070.1709

0.5154

0.00310.12690.22070.1647

0.00260.12120.22070.1709

0.5224

0.00310.13280.22260.1638

0.00210.12810.22210.1701

0.5224

0.00310.13280.22260.1638

0.0021

0.1281

0.2221

0.1701

check yield = AR yld

5VDU WGO ON CRUDE5VDU LVGO ON CRUDE5VDU HVGO ON CRUDE5VDU VR ON CRUDE

5 VDU Asphalt Operation

5VDU WGO ON CRUDE5VDU LVGO ON CRUDE5VDU HVGO ON CRUDE5VDU ASP ON CRUDE

6VDU AT 65 MBPD (SVD7)

6VDU WGO ON CRUDE6VDU LVGO ON CRUDE6VDU HVGO ON CRUDE6VDU VR ON CRUDE

DBALW15DBALLl 5DBALH15DBALV15

DBALW25DBALL25DBALH25DBALAS5

DBALW26DBALL26DBALH26DBALV26

VAC YIELDS (VOLUME) AS PROPERTY OF ATM RESID (1, 2, 5 CDU)

0.09930.50630.3945

1

0.00200.07030.61430.04600.2675

1

0.09930.50630.3945

1

0.00200.07030.61430.04600.2675

1

0.10230.50830.3895

1

0.00200.07030.61830.04600.2635

1

0.10230.50830.3895

1

0.00200.07030.61830.04600.2635

1

0.08660.48490.4285

1

0.08660.48490.4285

1

0.08850.4869

0.42451

0.08850.4869

0.42451

1 VDU Normal Mode

IVDU on Atm Res-WGOlVDUon AtmRes-DGOIVDU on Atm Res-VResCHECK

1 VDU Asphalt mode

IVDU LWGO ON RESIDIVDU WGO ON AT RESIDIVDU DGO ON ATRESIDIVDU BSGO ON AT RES.IVDU ASP ON AT RESIDCHECK

IWIlRAlILlIRAlIVIlRAl

ILWlRBlIW21RB1IL21RB1IBSlRBlIASlRBl

1 VDU WITH BSGO PRODUCTION

0.0060

0.2700

0.0060

0.2700

0.0060

0.27700.00600.2770

0.00600.2462

0.00600.2462

0.06060.59190.03700.3105

0.00600.2462

0.06060.59190.03700.3105

0.00600.2462

0.06160.59590.03800.3045

0.00600.2542

0.06160.59590.03800.3045

0.00600.2542

IVDU WGO ON AT RESIDIVDU LVGO ON ATRESIDIVDU BSGO ON AT RES.IVDU VRES ON AT RESIDCHECK

5VDU AT 33 MBPD

5VDU WGO ON AT RESID5VDU LVGO ON ATRESID

IW31RA1IL31RA1IBS3RA1IV31RA1

IW15RA1ILl 5RAl

0.00600.27030.45930.2645

1

0.00600.27030.45930.2645

1

0.43850.2855

0.43850.2855

1

0.43650.2805

1

0.43650.2805

1

0.42820.3196

1

0.4282

0.3196

1

0.42820.3196

1

0.42820.3196

1

0.42620.3136

1

0.42620.3136

1

5VDU HVGO ON ATRESID5VDU VR ON AT RESIDCHECK

5 VDU Asphalt Mode5VDU WGO ON AT RESID5VDU LVGO ON ATRESID5VDU HVGO ON ATRESID5VDU ASP ON AT RESIDCHECK

IH15RA1

IV15RA1

IW25RB1IL25RB1IH25RB1IAS5RB1

VDU YIELDS (LV) AS PROPERTY OF ATM RESIDS EX CDU 1, 2 & 5

0.0060.2567680.4555190.281713

1

0.0060.2567680.4555190.281713

1

0.0050.2677680.4485190.278713

1

0.0050.2677680.4495190.278713

1

0.0050.2362250.4401660.318609

1

0.0050.2362250.4401660.318609

1

0.00500.23620.44020.3186

1

0.00500.23620.44020.3186

1

0.00400.24620.43620.3136

1

0.00400.24620.43620.3136

1

6 VDU AT 50 MBPD

6VDU WGO ON ATRESID6VDU LVGO ON ATRESID6VDU HVGO ON ATRESID6VDU VR ON AT RESIDCHECK

IW16RA1IL16RA1IH16RA1IV16RA1

VAC YLD AS PROPERTY OF VAC RESID (3, 4 CDU)

0.3880330.611967

1

0.323790.67621

1

0.3880330.611967

1

0.323790.67621

1

00.09926

0.5187790.381962

1

0.0680110.5162820.415707

1

00.09926

0.5187790.381962

1

0.0680110.5162820.415707

1

0.36530.6347

1

0.29030.7097

1

0.3653

0.6347

1

0.29030.7097

1

0.00800.06750.50860.4158

1

0.05650.48460.4588

1

0.00800.06750.50860.4158

1

0.05650.48460.4588

1

5 VDU Normal mode

5VDU WGO ON V. RESID5VDU LVGO ON V.RESID5VDU HVGO ON V.RESID5VDU VR ON V. RESIDCheck

6 VDU AT 65 MBPD

6VDU WGO ON V. RESID6VDU LVGO ON V.RESID6VDU HVGO ON V.RESID6VDU VR ON V. RESIDCheck

ATMOS CUT PROPERTIES

IW15VA3IL15VA3IH15VA3IV15VA3

IW26VA3IL26VA3IH26VA3IV26VA3

Properties in BLNGASO : RVP, 230, FPI, OLE, LSRLSl-CDULSR

0.66620.00342.061.082.060.081.048.0

0.66620.00342.061.082.060.081.048.0

0.67950.005

24.051.572.450.571.451.0

0.74150.014

4.29

43.0

0.67950.005

24.051.572.450.571.451.0

0.74530.016

4.29

47.3

0.66260.003

51.064.585.563.584.547.0

0.66260.00351.064.585.563.584.547.0

0.66390.00243.061.082.060.081.047.0

0.66390.00243.061.082.060.081.047.0

0.66740.00340.061.082.060.081.048.0

0.66740.00340.061.082.060.081.048.0

0.66950.017

51.061.582.560.581.548.0

0.66950.01751.061.582.560.581.548.0

0.67620.018

38.0

54.575.553.574.547.0

0.74560.025

4.99

36.4

0.67620.018

38.0

54.575.553.574.547.0

0.75020.037

4.99

39.6

0.66630.01660.063.584.562.583.546.0

0.66630.016

60.063.584.562.583.546.0

0.66660.017

56.061.582.560.581.546.0

0.66660.017

56.061.582.560.581.546.0

0.65630.018

50.061.582.560.581.547.0

0.65630.018

50.061.582.560.581.547.0

LSR - Spec GravLSR - SulfurLSR - %VAP @ 130LSR-RONLSR - RON 3CCLSR - MONLSR - MON 3CCLSR - VLPT

MSR - Spec GravMSR - SulfurMSR - RVPMSR - Freeze IndexMSR-N +2A

ISPGLSlISULLSlI130LS1IRONLSlIR30LS1IMONLSlIM30LS1IVLPLSl

ISPGMN4ISULMN4IRVPMN4IFPIMN4

IN2AMN4

Table 13-17Continued

5CDUB5K

5CDUB5N

4CDUB4K

4CDUB4N

3CDUB3K

3CDUB3N

2CDUB2K

2CDUB2N

1CDUB1K

1CDUB1N

5CDUA5K

5CDUA5N

4CDUA4K

4CDUA4N

3CDUA3K

3CDUA3N

2CDUA2K

2CDUA2N

1CDUA1K

1CDUA1NMODE

0.72630.0117.637.6

0.7857

24

-198

-181

0.84851.148240573354.2-50

0.73090.0147.639.7

0.78630.112-315262466.9-197-181

0.84851.148240573354.2-50

0.78940.205-23365.52861.8-195-178

0.84090.804187663954.5-82

0.87181.6454846749.26239

0.91442.586

0.79360.1210.764.66636-191-175-28228.9

0.79140.205-23365.53261.8-193-177

0.84090.804187663954.5-82

0.87181.6454846749.26239

0.9144

2.586

0.72480.0129.036.6

0.7874

26

-196-180

0.85561.271300

34

1552.5-24

0.9088

2.480

0.72820.0149.038.1

0.78870.105-305292766.4-195-179

0.8556

1.271

300

34

1552.5-24

0.90882.480

0.72400.010

7.636.6

0.7892

29

-195-178

0.8504

1.1692206338

53.7-45

0.94633.41

434.7

0.73020.013

7.639.5

0.78900.091-303

3028

66.4-195-179

0.85041.169

2206338

53.7-45

0.94633.41

434.7

0.72840.013

6.938.5

0.7865

25

-197-181

0.84281.029

197

5732

55.3

-72

0.94593.38

431.7

0.73310.017

6.940.6

0.78810.094-31029.6

2666.4

-196-179

0.84281.029

197

5732

55.3-72

0.94593.38

431.7

0.73070.0277.634.1

0.7855

22

-198-181

0.84241.160240563157.2-50

0.94653.17448.1

0.73480.0287.634.7

0.78620.125-310292367.6-198-181

0.84241.160240563157.2-50

0.9465

3.17

448.1

0.78800.237-22275.72463.2-196-179

0.83440.840190774857.4-76

0.86811.6775752551.56742

0.9113

2.365

0.79400.1430.758.266.436-191-175-26732.3

0.80240.237-22275.75663.2128

0.8344

0.840

190

774857.4-76

0.86811.6775752551.56742

0.9113

2.365

0.7284

0.028

9.7

31.5

0.7873

25

-197

-180

0.85111.320308341457.1-19

0.9058

2.265

0.73150.0319.732.7

0.78840.119-29634.12567.2-196-179

0.85111.320308341457.1-19

0.90582.265

0.73000.026

8.335.3

0.7893

28

-195-178

0.84611.251

2356439

56.6-37

0.94653.17

448.1

0.73380.029

8.334.1

0.78900.104-291

3428

67.2-195-179

0.84611.251

2356439

56.6-37

0.94653.17

448.1

0.73220.029

7.634.9

0.7865

23

-197

-181

0.83911.100

1975833

57.9-68

0.94633.14

446.1

0.73640.033

7.634.9

0.78790.107-303

3324

67.1-196-179

0.83911.100

1975833

57.9-68

0.94633.14

446.1

HSR - SGHSR - SULHSR - RVPHSR-N + 2AHSR - Diesel IndexHSR - Pour IndexHSR - 144 IndexHSR - 154 IndexHSR - H ValueHSR - Freeze Index

Kero - SGKero - SuIKero - H ValueKero - Freeze IndexKero - Pour IndexKero - Diesel IndexKero - 144 IndexKero - 154 Index

LDO - SGLDO - SuILDO - Pour IndexLDO - 144 IndexLDO - 154 IndexLDO - Diesel IndexLDO - H Value

M/ID-SGM^D-SuIM/ID - H ValueM/ID - Pour IndexM/ID - Diesel IndexM/ID - 144 IndexM/ID - 154 Index

Atm Res - SGAtm Res - SuIAtm Res - H Value

HDO - SG

HDO - SuI

ISPGHNlISULHNlIRVPHNlIN2AHN1IDIIHNlIPPIHNlI144HN1I154HN1IVBIHNlIFPIHNl

ISPGKNlISULKNlIVBIKNlIFPIKNlIPPIKNlIDIIKNlI144KN1I154KN1

ISPGDNlISULDNlIPPIDNlI144DN1I154DN1IDIIDNlIVBIDNl

ISPGMI4ISULMI4IVBIMI4IPPIMI4IDIIMI4I144MI4I154MI4

ISPGRAlISULRAlIVBIRAl

ISPGHD3

ISULHD3

261147355360.07

0.99934.389670.715.3291921.5990.3

261147355360.07

0.99934.389670.715.3291921.5990.3

234125157370.04

0.96973.835540.010.63382431.3523.2

234125157370.04

0.96973.835540.010.63382431.3523.2

271150757370.07

0.99654.030661.213.4312021.5990.3

271150757370.07

0.99654.030661.213.4312021.5990.3

244128758380.04

0.96723.522542.08.93392531.3523.2

244128758380.04

0.96723.522542.08.93392531.3523.2

IVBIHD3 HDO - H ValueIPPIHD3 HDO - Pour IndexI144HD3 HDO - 144 IndexI154HD3 HDO - 154 IndexICONHD3 HDO - Con Carbon

ISPGVA3 Vac Res - SGISULVA3 Vac Res - SuIIVBIVA3 Vac Res - H ValueICONVA3 Vac Res - Con CarbonI144VA3 Vac Res - 144 IndexI154VA3 Vac Res - 154 IndexIDIIVA3 Vac Res - Diesel IndexIPPIVA3 Vac Res - Pour Index

* DEFERRED CUT PROPERTIES

0.85681.332

367-1254.1

0.91282.5821641

255

1.01654.639

74820.1

22

15

0.8461.134

268-29

54.7

0.91832.7121972284

0.91562.471

0.85681.332

367-1254.1

0.91282.5821641

255

1.01654.639

74820.1

22

15

0.8461.134

268-29

54.7

0.91832.7121972284

0.91562.471

0.8591.369

378

-454.1

0.91222.5671610

252

1.01654.640

74820.1

22

15

0.85851.171

277-2954.1

0.91742.6911941280

0.9149

2.46

0.8591.369

378-4

54.1

0.91222.5671610

252

1.01654.640

74820.1

2215

0.85851.171

277-2954.1

0.91742.6911941280

0.91492.46

0.85361.373

378-4

50.2

0.9099

2.3621562264

1.00764.029

71216.6

2617

0.8431.189

276-4754.7

0.91562.471

0.85361.373

378-4

50.2

0.90992.3621562264

1.00764.029

71216.6

2617

0.8431.189

276-4754.7

0.91562.471

0.85541.408

3884

50.2

0.9093

2.3521541261

1.00764.029

71216.6

2617

0.84351.196

260-4654.1

0.91492.46

0.85541.408

3884

50.2

0.90932.3521541261

1.00764.029

71216.6

2617

0.84351.196

260-4654.1

0.91492.46

* IVDU Normal mode

ISPGWl 1 IVDU WGO - SGISULWl 1 IVDU WGO - SuIIPPIWl 1 IVDU WGO - Pour IndIVBIWl 1 IVDU WGO - H ValueIDIIWl 1 IVDU WGO - Diesel Ix

ISPGLIl IVDUDGO-SGISULLl 1 IVDU DGO - SuIIPPILl 1 IVDU DGO - Pour IndIVBILl 1 IVDU DGO - H Value

ISPGVl 1 IVDU VR - SGISULVIl IVDU VR-SuIIVBIV11 1VDU V R - H ValueICONV11 IVDU VR - Con CarbonI144V11 IVDU VR - 144 IndexI154V11 IVDU VR - 154 Index

* IVDU Asphalt Mode

ISPGW21 1VDU WGO - SGISULW21 IVDU WGO - SuIIPPIW21 IVDU WGO - Pour IndIVBIW21 IVDU WGO - H ValueIDIIW21 IVDU WGO - Diesel Ind

ISPGL21 1VDU DGO - SGISULL21 1VDU DGO - SuIIPPIL21 IVDU DGO - Pour IndIVBIL21 1VDU DGO - H Value

1 VDU bsgo mode

ISPGW31 IVDU WGO - SGISULW31 IVDU WGO - SuIIPPIW31 1VDU WGO - Pour IndIVBIW31 IVDU WGO - H VaIu3

IDIIW31 1VDU WGO - Diesel IndISPGL31 IVDU DGO - SGISULL31 IVDU DGO - SuI

Table 13-17Continued

5C0UB5K

5C0UB5N

4CDUB4K

4C0UB4N

3CDUB3K

3CDUB3N

2CDUB2K

2C0UB2N

1CDUB1K

1CDUB1N

5CDUA5K

5CDUA5N

4CDUA4K

4CDUA4N

3CDUA3K

3CDUA3N

2CDUA2K

2CDUA2N

1CDUA1K

1CDUA1NMODE

1893292

1893292

1872

289

1872289

1893292

1.02174.245

77221.4

1893292

1.02174.245

77221.4

1872

289

1.0220

4.249

774

21.5

1872

289

1.02204.249

77421.50.220.15

IVDU DGO - Pour IndIVDU DGO - H Value

IVDU VR - SGIVDU VR - SuIIVDU V R - H ValueIVDU VR - Con Carbon

IPPIL31IVBIL31

ISPGV31ISUL V31IVBIV31ICONV31I144V31I154V31

* 5 VDU Normal mode

0.81120.385

56-20064.2

15-5

0.87421.916

52563

48.76037

0.81120.385

56-20064.2

15-5

0.87421.916

52563

48.76037

0.88562.161

722128

44.857.635.8

0.88562.161

722128

44.857.635.8

0.81120.385

56-20061.3

4318

0.87421.916

52563

48.762.138.7

0.81120.385

56-20061.3

4318

0.87421.916

52563

48.762.138.7

0.81120.385

56-20060.8

4923

0.87561.939

54067

48.462.238.9

0.81120.385

56-20060.8

4923

0.87561.939

54067

48.462.238.9

0.81640.530

61220

64.4-101

-99

0.87031.910

56072

51.56138

0.81640.530

61220

64.4-101-99

0.87031.910

56072

51.56138

0.80450.259

93180

62.1254

0.88542.158

779145

48.457.9

36

0.80450.259

93180

62.1254

0.88542.158

779145

48.457.9

36

0.81640.530

61220

62.6-101-99

0.87031.910

56072

51.561.137.6

0.81640.530

61220

62.6-101

-99

0.87031.910

56072

51.561.137.6

0.81550.460

61185

62.55024

0.87161.932

56078

51.263.539.7

0.81550.460

61185

62.55024

0.87161.932

56078

51.263.539.7

5VDU WGO - SG5VDU WGO - SuI5VDU WGO - Pour Ind5VDU WGO - H Value5VDU WGO - Diesel Ind5VDU WGO - 144 Index5VDU WGO - 154 Index

5VDU LVGO - SG5VDU LVGO - SuI5VDU LVGO - Pour Index5VDU LVGO - H Value5VDU LVGO - DsI Indx5VDU LVGO - 1445VDU LVGO - 154

ISPGW15ISULW15IPPIW15IVBIW15IDIIW15I144W15I154W15

ISPGL15ISULL15IPPIL15IVBIL15IDIIL15I144L15I154L15

* DEFERRED CUT PROPERTIES

0.94163.243100400

4730

1.03724.91

813.0261812

0.94163.243100400

4730

1.03724.91

813.0261812

0.95053.573500446

4429

1.02754.86

800.023.9

2114

0.95053.5735004464429

1.02754.86

800.023.9

2114

0.94253.2631004044630

1.02984.88

804.025.3

2113

0.94253.2631004044630

1.02984.88

804.025.3

2113

0.94163.24

31004004730

1.03724.91

813.0261812

0.94163.2431004004730

1.03724.91

813.0261812

0.9416

3.24131004004730

1.04024.91

814.026.4

1811

0.94163.24131004004730

1.04024.91

814.026.4

1811

0.93882.86628004024831

1.02494.49

781.021.5

2315

0.93882.86628004024831

1.02494.49

781.021.5

2315

0.95033.06131004394429

1.02014.39

770.020.2

2416

0.95033.06131004394429

1.02014.39

770.020.2

2416

0.94322.8728004044630

1.02084.48

776.021.2

2416

0.94322.8728004044630

1.02084.48

776.021.2

2416

0.93882.86628004024831

1.02494.49

781.021.5

2315

0.93882.86628004024831

1.02494.49

781.021.5

2315

0.93862.86428004014831

1.02524.49

782.021.9

2315

0.93862.8642800401

4831

1.02524.49

782.021.9

2315

5VDU HVGO - SG5VDU HVGO - SuI5VDU HVGO - Pour Ind5VDU HVGO - H Value5VDU HVGO - 1445VDU HVGO - 1545VDU VR - SG5VDU VR - SuI5VDU VR - VBI5VDU VR - Con Carbon5VDU VR - 144 Index5VDU VR - 154 Index

ISPGH15ISULH15IPPIH15IVBIH15I144H15I154H15ISPGV15ISULV15IVBIV15ICONV15I144V15I154V15

0.81340.458

68-19060.5

-340-296

0.87371.906

52561

48.86037

0.93793.1632856

3834831

1.03254.9

816.0262013

0.81340.458

68-19060.5

-340-296

0.87371.906

52561

48.86037

0.93793.16328563834831

1.03254.9

816.0262013

0.95093.44033794434429

1.02324.8

774.022.2

2215

0.95093.44033794434429

1.02324.8

774.022.2

2215

0.88612.154

654117466341

0.93623.1192676

3744831

1.02794.8

795.0242114

0.88612.154

654117466341

0.93623.1192676

3744831

1.02794.8

795.0242114

0.81340.458

68-19060.5

-340-296

0.87371.906

52561

48.86037

0.93793.1632856

3834831

1.03254.5

816.0262013

0.81340.458

68-19060.5

-340-296

0.87371.906

52561

48.86037

0.93793.16328563834831

1.03254.5

816.0262013

0.81880.543

81-16759.5

-331-2880.8741.907

52261

48.76138

0.93793.1592856

3834831

1.03264.5

816.0262013

0.81880.543

81-16759.5

-331-2880.8741.907

52261

48.76138

0.93793.1592856

3834831

1.03264.5

816.0262013

0.81580.58

79-16461.4

-336-292

0.87031.907

55172

51.56239

0.93482.7952609

3854932

1.02524.5

781.021.1

2315

0.81580.58

79-16461.4

-336-292

0.87031.907

55172

51.56239

0.93482.79526093854932

1.02524.5

781.021.1

2315

0.94763.0093065

4414529

1.01734.4

748.018.2

2516

0.94763.0093065441

4529

1.01734.4

748.018.2

2516

0.88222.113

682127

48.96541

0.9332.7572477

3755032

1.02104.4

764.019.5

2416

0.88222.113

682127

48.96541

0.9332.7572477

3755032

1.02104.4

764.019.5

2416

0.81580.58

79-16461.4

-336-292

0.87031.907

55172

51.56239

0.93482.79526093854932

1.02524.5

781.021.1

2315

0.81580.58

79-164

-336-292

0.87031.907

55172

51.56239

0.93482.7952609

3854932

1.02524.5

781.021.1

2315

0.820.664

92-14460.7

-329-286

0.87051.9154772

51.46339

0.93482.79526093854932

1.02544.5

782.021.2

2315

0.820.664

92-14460.7

-329-286

0.87051.91547

7251.4

6339

0.93482.7952609

3854932

1.02544.5

782.021.2

2315

6 VDU 65 mbpd

6VDU (65) WGO - SG6VDU (65) WGO - SuI6VDU (65) WGO - PI6VDU (65) WGO - H6VDU (65) WGO - DI6VDU (65) WGO - 1446VDU (65) WGO - 1546VDU (65) LVGO - SG6VDU (65) LVGO - SuI6VDU (65) LVGO - Pi6VDU (65) LVGO - H6VDU (65) LVGO - DI6VDU (65) LVGO - 1446VDU (65) LVGO - 154

6VDU (65) HVGO - SG6VDU (65) HVGO - SuI6VDU (65) HVGO - PI6VDU (65) HVGO - H6VDU (65) HVGO - 1446VDU (65) HVGO - 154

6VDU (65) VR - SG6VDU (65) VR - SuI6VDU (65) V R - H6VDU (65) VR -Carbon6VDU (65) VR - 1446VDU (65) VR - 154

ISPGW26ISULW26IPPIW26IVBIW26IDIIW26I144W26I154W26ISPGL26ISULL26IPPIL26IVBIL26IDIIL26I144L26I154L26

ISPGH26ISULH26IPPIH26IVBIH26I144H26I154H26

ISPGV26ISULV26IVBIV26ICONV26I144V26I154V26

The fifth set of rows is used to represent CDUs capacities. There aresome other rows in this set, starting with E, L, or G, showing that it is equalto, less than, or greater to that row. These are control rows. The row namesin this set are seven characters long and span all crude unit submodels.

CRDDISTL TABLE

This table is used by the model to define the structure of a number oftheoretical or logical crude distillation submodels. Each logical crude unitmay be considered one of many modes of operation of a crude unit. Thistable provides mapping between the Assays Table data and these logicalcrude units. Table 13-18 is an example of this table. The column namesare three character tags for various operation modes of a crude units.Where individual crudes are being segregated, it may be convenient touse crude tags as logical unit tags, but this is not a requirement.

The rows of this table are divided into four sets. The first set comprisesrow names ATMTWR and VACTWR. The entries in these rows areinteger values indicating which physical crude distillation towers are usedby various logical crude units.

The second set of rows are ESTxxx, where xxx is the crude tag. Theentries in these rows define the estimated charge of each crude to each logicalcrude unit. These estimates need not be accurate. The charge estimates areeither on a weight or volume basis, depending on how crude assay data areentered. Thus, if the crude assay data are on a volume basis, entries in thistable should be in volume units. The LP model uses these data to calculate theproperties of straight-run cuts from a predefined mix of crude.

The next set of rows in this table are named ATMuuu and VACuuu andthese define the consumption of utilities (fuel, steam, electricity, coolingwater etc) in atmospheric and vacuum units for each of logical crude units.

CRDCUTS TABLE

The CRDCUTS Table defines the crude distillation cutting schemeused in the model. The row names are the three-character stream tags ofthe straight-run distillation cuts (see Table 13-19).

The column TYPE is used to identify the type of cut, and each cut mustbe allocated one of the following numbers:

Generally the vendor supplied LP packages have an in-builtmechanism to generate an Atmospheric Distillation Unit sub model

Table 13-18CRDDISTL Table

TABLECRDDISTL TEXT LC1 LC2 LC3 LC4 LC5

REHNERY CONFIGURATION

ATMTWR PHYSICALCDU 1 2 3 4 5

VACTWR PHYSICALVDU 3 4

CRUDE TO UNIT ESTIMATE

ESTAlN Chg AB ICDU Normal 1.000ESTAlK Chg AB ICDU Kero 1.000ESTBlN Chg Bah ICDU Normal 1.000ESTBlK Chg Bah ICDU Kero 17.000ESTA2N Chg AB 2CDU Normal 1.000ESTA2K Chg AB 2CDU Kero 1.000ESTB2N Chg Bah 2CDU Normal 1.000ESTB2K Chg Bah 2CDU Kero 17.000

ESTA3N Chg AB 3CDU Normal 61.000ESTA3K Chg AB 3CDU Kero 1.000ESTB3N Chg Bah 3CDU Normal 1.000ESTB3K Chg Bah 3CDU Kero 1.000

ESTA4N Chg AB 4CDU Normal 100.000ESTA4K Chg AB 4CDU Kero 1.000ESTB4N Chg Bah 4CDU Normal 1.000ESTB4K Chg Bah 4CDU Kero 1.000

ESTA5N Chg AB 5CDU Normal 28.000ESTA5K Chg AB 5CDU Kero 2.000ESTB5N Chg Bah 5CDU Normal 28.000ESTB5K Chg Bah 5CDU Kero 2.000

TOTAL CRUDE EST

265.00020.000 20.000 64.000 103.000 58.000

UTILITY CONSUMPTIONS (MSCF NATURAL GAS)

ATMFUL FULATMTOWER 0.1683 0.1683 0.2049 0.1829 0.1683

NOTE: THIS TABLE DEFINES THE ATMOS/VACUUM LOGIC. ONLY INTEGRALCRUDE/VACUUM UNITS NEED BE NOTED HERE (I.E., 3 AND 4).

using data supplied by user in tables Assay, CRDDISTL, andCRDCUTS. The type of cut naming convention used in the LPpackage must be used. The cut type or number used here (0, 1, 2,3, 9) are as per PIMS LP Package.

Table 13-19CRDCUTS Table

TABLECRDCUTS TEXT TYPE LC1 LC2 LC3 LC4 LC5*

GAl OFF GASES (C3 MINUS) 1 1 1 1 1 1C41 CDUC3/C4 1 1 1 1 1 1LSI CDULSR 1 1 1 1 1 1

MN4 4AMSRPool 1 4

HNl HSR 39.5 C FLASH 1 1 2 3 4 5HA4 HSR for KRU (Arab) 1 4HB4 HSR for KRU (Bah) 1 4KNl KERO 39.5C FLASH 1 1 2 3 4 5KAl Kero for KRU (Arab) 1 1 2 3 5KBl Kero for KRU (Bah) 1 1 2 3 5

DNl CDULIGHTDIESEL 1 1 1 1 4 1MI4 M + I DSL FROM 4A 1 4RAl ATM RESID 1/2/5 (Arab) 1 1 2 1 1 5RBl ATM RESID 1/2/5 (Bah) 1 1 2 1 1 5HD3 HVY DSL 3 & 4 CDU 3 3 4VA3 VAC RES 3 & 4 CDU 3 3 4

DEFERRED CUTS

WIl IVDU WGO POOL 9 1 1LIl IVDU LVGO POOL 9 1 1VIl 1 VDU VAC RES POOL 9 1 1LWl 1 VDU LWGO POOL (Asp) 9 1 1W21 1 VDU LVGO POOL (Asp) 9 1 1L21 1 VDU VAC RES POOL (A) 9 1 1BSl 1 VDU BSGO 9 1 1ASl 1 VDU ASPHALT 9 1 1W31 lVDUWGOPOOL(BSGO) 9 1 1L31 1 VDU DGO POOL (BSGO) 9 1 1BS3 1 VDU BSGO (BSGO) 9 1 1V31 1 VDU VAC RES POOL (BSGO) 9 1 1

W15 5 VDU WGO POOL 9 1 1 1 1L15 5 VDU LVGO POOL 9 1 1 1 1H15 5 VDU HVGO POOL 9 1 1 1 1 1V15 5 VDU VAC. RESID POOL 9 1 1 1 1 1W25 5 VDU WGO POOL (Asp) 9 1L25 5 VDU LVGO POOL (Asp) 9 1H25 5 VDU HVGO POOL (Asp) 9 1AS5 5 VDU ASPHALT 9 1

W16 6 VDU WGO AT 50 MBPD 9 1 1 1L16 6 VDU LVGO AT 50 MBPD 9 1 1 1 1

Table 13-19Continued

TABLECRDCUTS TEXT TYPE LC1 LC2 LC3 LC4 LC5*

H16 6 VDU HVGO AT 50 MBPD 9 1 1 1 1 1V16 6 VDU VR AT 50 MBPD 9 1 1 1 1 1W26 6 VDU WGO AT 65 MBPD 9 1 1 1L26 6 VDU LVGO AT 65MBPD 9 1 1 1 1H26 6 VDU HVGO AT 65MBPD 9 1 1 1 1 1V26 6 VDU VR AT 65 MBPD 9 1 1 1 1 1W46 6 VDU WGOFROM WIl 9 1 1L46 6 VDU LVGO FROM WIl 9 1 1H46 6 VDUHVGOFROM WIl 9 1 1W56 6 VDU WGO FROM WIl 9 1 1L56 6 VDULVGOFROM WIl 9 1 1H56 6 VDUHVGOFROM WIl 9 1 1

0. This indicates that cut yield is identified in the assay data, butthis cut is produced by downstream separation, in a saturatedgas plant and not on a crude unit.

1. This indicates that this a straight-run atmospheric cut.2. This indicates that it is atmospheric residuum, which may be

used elsewhere or fractionated in a vacuum unit. If an atmo-spheric resid is always directed to a vacuum unit, it is omittedfrom the cutting scheme in this table.

3 . This indicates that it is a straight-run vacuum cut.9. This indicates it is a deferred cut that is not produced on a crude

distillation unit but in a downstream unit.

The other column names in this table are the three-character tags forthe logical crude units and must exactly match the column names of theCRDDISTL Table. The entry at each intersection is the pool number towhich the cut from each logical crude unit is directed.

For example, if this table contains a cut ABC, this stream yieldsstreams ABC in pool 1, AB2 in pool 2, and AB3 in pool 3. Thus, whena stream is segregated, the model automatically constructs additionalstream tags to identify the segregated stream. The third character in thestream tag is replaced with a pool number for pool 2 onward.

SCRD TABLE

The SCRD Table (Table 13-20) gives the disposition of crudes processedby the refinery to various crude distillation units. But only those crudes withnonblank entries in the material balance rows for crudes are available aspotential feed to that logical crude unit. Therefore, if a crude is omitted fromthe logical crude unit, it will not be processed on that unit. Thus, Table 13-20shows that crude ABP (Arab light) is processed on crude units 3, 4, and 5,while crude BAH (Bahrain crude) is processed only on crude units 1 and 2.

Tables 13-17 to 13-20 contain all the data on the crudes processed, theirdisposition, yield and properties, data on the physical atmospheric andvacuum distillation units present, their mode of operation, unit capacities,and utility consumption. The primary cuts from various crude units arepooled or segregated as per pooling map in the CRDCUTS Table. Thus,all refinery atmospheric distillation data is maintained in these tables. TheCDU models are automatically generated from them by the LP package.

CDU SUBMODEL STRUCTURE

It may be useful to review exactly how a matrix generator programprocesses data in the Assay Table to produce material and propertybalances for CDU streams. The Assay Table differs from other tables inthat it is not included in the matrix but is used by the program to build oneor more CDU tables, which are included in the matrix.

The name of actual CDU submodel tables built by the matrix generatorprogram is typically concocted by adding a character S (to denote sub-model) before the column names of the CRDDISTL Table. Thus, if thefirst column in this table is LCl, the first CDU table is named SLCl(PIMS Refinery LP Package).

The column names in the crude submodel tables are the operation modesof this crude distillation unit. Thus, AlN and AlK are the two operationmodes of crude distillation unit SLCl while processing light Arab crude, andB IN and BIK are the two operation modes while processing Bahrain crude.In the matrix generated from this table, the column names are SLClAlN,SLClAlK, SLClBlN, and SLClBlK. The row names would be identical tothe table CRDCUTS row names; for example, in this case, VBALGAl9V-BALC41, VBALLSl, and so on. The coefficients at row/column intersec-tions are the yields of various cuts of data entered in the Assay Table.

The atmospheric residuum from crude units becomes feed to VDUs.To avoid unnecessary multiplicity of streams, only one atmospheric

Table 13-20Disposition of Crudes

B5KB5NB4KB4NB3KB3NB2KB2NB1KB1NA5KA5NA4KA4NA3KA3NA2KA2NA1KA1NTEXTTABLESCRD

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1

1

-1-1

AL CRUDEBAH CRUDE

AB to 1 CDU NormalAB to 1 CDU KRRAB to 2 CDU NormalAB to 2 CDU KRRAB to 3 CDU NormalAB to 3 CDU KRRAB to 4 CDU NormalAB to 4 CDU KRRAB to 5 CDU NormalAB to 5 CDU KRR

Bah to 1 CDU NormalBah to 1 CDU KRRBah to 2 CDU NormalBah to 2 CDU KRRBah to 3 CDU NormalBah to 3 CDU KRRBah to 4 CDU NormalBah to 4 CDU KRRBah to 5 CDU NormalBah to 5 CDU KRR

VBALABPVBALBAH

VBALAlNVBALAlKVBALA2NVBALA2KVBALA3NVBALA3KVBALA4NVBALA4KVBALA5NVBALA5K

VBALBlNVBALBlKVBALB2NVBALB2KVBALB3NVBALB3KVBALB4NVBALB4KVBALB5NVBALB5K

resid stream is produced from the operation of one crude distillationcolumn, irrespective of number of crudes processed there or the num-ber of operation modes of the CDUs. This is done by pooling the variousresid streams from different modes of a crude column, as shown next forcrude distillation column 1 (SLCl). Also the yield and properties ofstreams produced from the vacuum distillation of this resid are deter-mined here, as these properties depend on the properties of the compositeresid stream generated here, even though the vacuum distillation streamsare not produced here. A part of Table SLCl follows, presenting poolingof resids from various operation modes of crude distillation column SLCl:

AlN AlK BIN BlK ARlVBALARl -0.5224 -0.5224 -0.5330 -0.5330RBALARl -0.5224 -0.5224 -0.5330 -0.5330 1ISPGARl 0.9463 0.9463 0.9459 0.9459RSPGARl -0.4943 -0.4943 -0.5041 -0.5041 999ISULARl 3.14 3.14 3.38 3.38IVBIARl 446.1 446.1 431.7 431.7RSULARl -1.6403 -1.6403 -1.8015 -1.8015 999RVBIARl -233.042 -233.042 -230.096 -230.096 999

The properties of the pooled stream ARl are calculated next.For example, consider the specific gravity of the pooled resid stream

ARl. This stream is generated by pooling volumes in the VBALARl row.Row RBALARl, which has the same coefficients as row VBALARl,represents how many barrels of resids from each operation mode of SLClare used to form the pool. The specific gravity of individual cuts is given byrow ISPGARl in the Assay Table. Row RSPGARl coefficients are formedby multiplying coefficients in row ISPGARl with the coefficient in rowRBALARl. For example, the coefficient of row RSPGARl in column AlNis the product of 0.9463*-0.5224, or 0.4943. The activity of this row is thesum of SG*barrels for the pooled stream. The SG of the composite streamcan be calculated by dividing the row activity of RSPGARl by the rowactivity of RBALARl, if column activities are known. Other properties ofthe composite streams can similarly be calculated.

It may be noted that, even though the rows VBALARl and RBALARlexhibit the same coefficients in the SLCl Table, there is an importantdistinction between them. VBALARl is a material balance row, represent-ing the actual physical production of atmospheric residue. RBALARl, onthe other hand, is a property balance row, which provides the denominatorfor computation of the average specific gravity of the pooled resid.

DBAL Rows (Deferred Cuts)

In the Assays Table, the yields for all atmospheric cuts, such as LPG,light naphtha, kerosene, or diesel, are represented by entries in VBALrows; for example, VBALLSl for LSR, VBALKNl for kerosene yield,and VBALARl for atmospheric resid streams. This is because thesestreams are produced directly from CDUs and their volumes as well asproperties are determined in the CDUs.

On the other hand, the vacuum product streams (LVGO, HVGO,V. RESID) and certain other streams, which are not produced on theCDU, are represented by DBALxxx type rows; for example, DBALWl 1,DBALLIl, and DBALHIl represent WGO, LVGO, and HVGO streamsfrom VDUl from the distillation of atmospheric resid from the CDUl.The presence of these deferred products in the Assays Table reflects thefact that their properties depend on the crude mix and CDU fractionation.That they are represented by DBAL and not VBAL rows reflects that theoption of exactly what volume of each stream is to be actually producedlies with the vacuum distillation units.

In the Assays Table the properties of the various atmospheric cuts anddeferred cuts are represented by the suffix I:

ISPGLl 1 Specific gravity of DGO.ISULLIl Sulfur of DGO.IVBILl 1 Viscosity blending index of DGO.

Consider distillate gas oil stream DGO, produced from VDU 1. Thisstream has no VBAL rows in the Assays Table. To calculate the specificgravity of a blend of streams, the LP multiplies the RBALLIl row withISPGLl 1 rows and again the resulting "gravity*barrels" are placed in rowRSPGLIl. Row RBALLIl has the same coefficients as row DBALARl,representing how many barrels of DGO distillate from each operationmode of SLCl are used to form the pool. RBALxxx is used as thedenominator to calculate the average stream property. The numerator isprovided by the activity of row RSPGLIl.

AlN AlK BIN BlK LIlDBALLIl -0.2544 -0.2544 -0.2709 -0.2709RBALLIl -0.2544 -0.2544 -0.2709 -0.2709 1ISPGLIl 0.9093 0.9093 0.9122 0.9122RSPGLIl -0.2313 -0.2313 -0.2471 -0.2471 999

VDU Yield as a Property of Vacuum Resids

In the Assay Table, there is a group of rows with special significance.This group of I rows specify a special set of properties of the atmosphericresid streams. These represent the yield of various products in the VDUfrom distillation of the atmospheric resids, for example, the followingrows:

IWl IARl Yield of WGO from atmospheric resid ARl on VDUl.ILIlARl Yield of DGO from atmospheric resid ARl on VDUl.IVIlARl Yield of V. RESID from atmospheric resid ARl on

VDUl.

Although treated as properties in the Assays Table, these are the yields ofproducts from the vacuum distillation of atmospheric resid streams, calledthe pseudoproperties of atmospheric resid because they are presented assimilar to the properties of the atmospheric resid in I-type rows.

Consider a portion of the Assays Table data for processing of Arab andBahrain crudes on CDUl. The following data present potential yields andproperties of various vacuum distillation cuts from processing atmos-pheric resids produced from various operation modes of atmosphericcrude distillation column CDUl, on vacuum distillation column VDU6:

AlN AlK BIN BlKVBALARl -0.5224 -0.5224 -0.5330 -0.5330

DBALW26 -0.0020 -0.0020 -0.0030 -0.0030DBALL26 -0.1280 -0.1280 -0.1210 -0.1210DBALH26 -0.2220 -0.2220 -0.2210 -0.2210DBALV26 -0.1700 -0.1700 -0.1710 -0.1710

IW26AR1 0.0040 0.0040 0.0050 0.0050IL26AR1 0.2452 0.2452 0.2352 0.2352IH26AR1 0.4250 0.4250 0.4282 0.4282IV26AR1 0.3256 0.3256 0.3316 0.3316

ISPGW26 0.8200 0.8200 0.8188 0.8188ISPGL26 0.8705 0.8705 0.8740 0.8740ISPGH26 0.9348 0.9348 0.9379 0.9379ISPGV26 1.0254 1.0254 1.0326 1.0326

In this table,

W26 = wet gas oil from distillation of CDUl atmospheric resid on VDU6.

L26 = LVGO from distillation of CDUl atmospheric resid on 6VDU6.

H26 = HVGO from distillation of CDUl atmospheric resid on 6VDU6.

V26 = vacuum resid from distillation of CDUl atmospheric resid on VDU6.

The yields of vacuum cuts are presented by DBAL rows instead ofVBAL rows, indicating that these cuts are not produced on the crudecolumn and the yields indicate only the potential yield of cuts from thevacuum column.

The second set of rows IW26AR1, IL26AR1, IH26AR1, and IV26AR1are the potential yields of WGO, LVGO, HVGO, and vacuum resid on theatmospheric resid feed (not on the crude) by the distillation of CDUlatmospheric resids on VDU6. Here, VDU6 yields of various cuts fromprocessing CDUl resid are indicated as a property of the feed resid.

Rows ISPGW26, ISPGL26, and the like indicate the properties of cuts(WGO, LVGO) from VDU6.

Referring to these Assays Table data, the following structure deter-mines the yield of various vacuum cuts from a vacuum column; forexample, VDU6 from a resid coming from mix of crudes processed onCDUl:

AlN AlK BIN BlK ARlRBALARl -0.5224 -0.5224 -0.5330 -0.5330 1

RW26AR1 -0.0021 -0.0021 -0.0027 -0.0027 999RL26AR1 -0.1281 -0.1281 -0.1281 -0.1281 999RH26AR1 -0.2220 -0.2220 -0.2282 -0.2282 999RV26AR1 -0.1701 -0.1701 -0.1767 -0.1767 999

Here, the coefficients in row RW26AR1 represent the yield of wet gasoil (WGO) from VDU6. The coefficient in column AlN in this row isobtained by multiplying the corresponding coefficients in row RBALARland row IW26AR1 (-0.5224 x 0.0040 = -0.0020). Similarly, the coef-ficient in row RV26AR1, column AlN is formed as a product of corres-ponding coefficients in RBALARl and IV26AR1 (-0.5224 x 0.3256 =-0.1701).

The overall yields of vacuum cuts W26 (WGO), L26 (LVGO), H26(HVGO), and V26 (vacuum resid) from the distillation of compositeatmospheric resid from crude unit 1 or SLCl is determined by dividingthe row activity of each RW26AR1, RL26AR1, RH26AR1, andRV26AR1 by the row activity of RBALARl once the column activitiesare known.

The 999 is a placeholder for the first guess of the yield of the vacuumproducts, required to start the recursion process.

The yields of vacuum cuts determined here are transmitted to variousvacuum distillation submodels for use.

Properties of VDU Streams

The properties of a vacuum distillation stream depends on the compos-ition of the atmospheric resids from which the VDU stream is produced.In the LP structure that follows, the specific gravities of W26 (WGO),L26 (LVGO), H26 (HVGO), and V26 (vacuum resid) from VDU6 aredetermined.

Here, the feed to VDU6 is atmospheric resid from crude distillationunit 1 (SLCl). Row DBALW26 gives the potential yield of WGO fromdifferent atmospheric resids from different modes of crude distillationcolumn 1. The coefficients in row RBALW26 are identical to those inrow DBALW26. The coefficient in row RSPGW26, for example, incolumn AlN, is formed by multiplying the coefficient in row RBALW26with the coefficient in row ISPGW26 (-0.0020 x 0.8200 - -0.0016).The specific gravity of the WGO stream is determined by dividing theactivity of row RSPGW26 by the activity of row RBALW26 once thecolumn activities are known:

• Specific gravity of stream W26, wet gas oil from VDU6 processingCDUl atmospheric resid.

AlN AlK BIN BlK W26DBALW26 -0.0020 -0.0020 -0.0030 -0.0030RBALW26 -0.0020 -0.0020 -0.0030 -0.0030 1RSPGW26 -0.0016 -0.0016 -0.0025 -0.0025 999

• Specific gravity of stream L26, LVGO from VDU6 processingCDUl atmospheric resid.

AlN AlK BIN BlK L26RBALL26 -0.1280 -0.1280 -0.1210 -0.1210 1RSPGL26 -0.1114 -0.1114 -0.1058 -0.1058 999

• Specific gravity of stream H26, HVGO from VDU6 processingCDUl atmospheric resid.

AlN AlK BIN BlK H26RBALH26 -0.2220 -0.2220 -0.2210 -0.2210 1RSPGH26 -0.2075 -0.2075 -0.2073 -0.2073 999

• Specific gravity of stream V26, vacuum resid from VDU6 proces-sing CDUl atmospheric resid.

AlN AlK BIN BlK V26RBALV26 -0.1700 -0.1700 -0.1710 -0.1710 1RSPGV26 -0.1743 -0.1743 -0.1766 -0.1766 999

Other properties (sulfur, viscosity blend index, pour index) of variousvacuum cuts are determined in an identical manner.

We see that both the properties and potential yields of vacuum cuts aredetermined in an atmospheric crude distillation model, where the feed tovacuum distillation unit originates and relative ratios of various crudes ortheir operating modes of CDU are available. The yield and property dataof vacuum cuts can be retrieved in VDU submodels to give the properyield of the vacuum stream from each atmospheric resid charged toa given vacuum unit.

The advantage of modeling vacuum yields as pseudoproperties ofatmospheric resids in the Assays Table is that all vacuum unit yield dataare maintained in a single table, the Assays Table. The use of pseudo-properties allows the flexibility to add unlimited number of crudes to anyCDU and still obtain the correct yields in VDU submodels withoutmodifying the VDU submodels in any way.

Although the use of deferred distillation rows and a number of pseudo-property rows in the Assays Table appears to complicate the model, thisadditional structure in the table enormously simplifies the modeling

VDUs as well as the addition of crude to the model and model main-tenance in general. The advantages of deferred distillation becomesapparent in VDU submodels.

VACUUM DISTILLATION UNIT MODELING

In refineries in which each CDU has its own associated VDU, model-ing a composite crude and vacuum unit becomes easy, and yields from thevacuum unit are treated exactly like those from CDU. However, inrefineries where atmospheric residuum from a given CDU can go to anumber of VDUs, one cannot treat CDUs and VDUs as a single combina-tion, since one does not know in advance in which VDU a given atmos-pheric residue will be processed nor which set of vacuum streams will beproduced.

Consider the following VDU6 model. Here, the feed is ARl, theatmospheric resid from CDUl. The product streams are

W62 Wet gas oil.L62 LVGO.H62 HVGO.V62 Vacuum resid.

In the SVD6 Table,

ARl W26 L26 H26 V26VBALARl 1VBALW26 1VBALL26 1VBALH26 1VBALV26 1VBALWG6 - 1VBALVM6 - 1VBALVH6 - 1VBALVR6 - 1EW26AR1 -999 1EL26AR1 -999 1EH26AR1 -999 1EV26AR1 -999 1

In rows EW26AR1, EL26AR1, EH26AR1, and EV26, the second tofourth characters match the names of pseudoproperties of ARl, whichwere defined in the Assays Table to represent the yields on VDU6 ofWGO, LVGO, HVGO, and vacuum resid, respectively. In the SVD6Table, these E (equality) rows all have entries of —999 in column ARl.The matrix generator program will substitute, for —999, the current yieldof each vacuum product, as calculated in the Assays Table for CDUlatmospheric resid. Thus, the correct vacuum yields for a mix of crudesprocessed on CDUl is calculated in CDUl submodel and transmitted toVDU6 submodel in column ARl.

Now, let us see how the yields transmitted into ARl are utilized. Forexample, consider the vacuum resid yields represented in row EV26AR1.The program will substitute for —999 in column ARl, the yield ofvacuum resids from ARl.

Suppose this is 0.33 or 33%. Then, -0.33 is substituted for -999.Further suppose that 1 mb (million barrels) of CDUl atmospheric residARl is charged to VDU6; then, the volume placed into row EV26AR1 incolumn ARl is as follows:

1 mb ARl x 0.33 (yield of vacuum resid) = —0.33 mb vacuum resid

The negative sign denotes production. The only other entry in rowEV26AR1 is a positive 1 in column V26. Since this is an equality row thatmust balance, column or variable V26 takes on an activity equal to thevolume of vacuum resid contained in CDUl atmospheric resid charged toVDU6. The activities of the other columns W26, L26, H26 are similarlydetermined by these E rows.

Other entries shown in column V26 are —1, representing production, inrow VBALVR6 +1 , representing consumption, in row VBALV26.Therefore we are actually producing not stream V26, which is VDU6vacuum resid derived from CDUl atmospheric resid, but VR6, the overallvacuum resid produced on VDU6 from all atmospheric resids fromdifferent CDUs. This is consistent with the physical reality of therefinery, where all atmospheric resids are processed as a mixture to producea single set of vacuum products from a VDU.

A vacuum distillation unit may have more than atmospheric resid feed.Let us add one more resid, AR3 coming from CDU3, to thepreceding structure, as shown next, this time showing only vacuum residproduction:

ARl V26 AR3 V36 VR6VBALARl 1VBALAR3 1VBALV26 1VBALV36 1VBALVR6 - 1 - 1EV26AR1 -999 1EV36AR3 -999 1

RBALVR6 - 1 - 1 1RSPGVR6 -999 -999 999RSULVR6 -999 -999 999RVB1VR6 -999 -999 999

We see that the structure in this table for AR3 is exactly parallel to thatfor ARl. Column V36 has activity equal to the volume of VDU6-derivedvacuum resid derived from CDU3, just as the activity of column V26represents the VDU6 vacuum resid derived from CDUl.

Note that both columns V26 and V36 have entries of —1 in rowVBALVR6, showing that these resids coming from different CDUscombine into a single vacuum resid stream, VR6. Columns V26 andV36 have +1 entries in material balance rows VBALV26 andVBALV36, indicating that these streams are consumed to form streamVR6.

To estimate the properties of the composite vacuum resid stream, rowRBALVR6 shows the components that form the stream, in the form ofcolumns that have —1 entries in this row, that is, V26 and V36. Theproperties (SG, SUL, VBI, etc.) of V26 and V36 are calculated in theCDUl and CDU3 submodels and transmitted here to replace the place-holders -999. Placeholder 999, in column VR6, is the first guess of thepooled stream to start the recursion process.

To summarize, the advantage of modeling vacuum distillation withdeferred cuts and the stream's pseudoproperties are as follows:

1. The calculation of all VDU yields and stream properties are done inthe Assay Table and transmitted to the respective VDU model. TheVDU models themselves contain no yield data. All data mainte-nance is only through the Assays Table.

2. Only one atmospheric resid stream is produced for each CDU,irrespective of the number of crudes processed in it. In the absence

of deferred distillation, one atmos resid is generated for everycrude.

3. For each VDU, only one set of vacuum streams is produced, ratherthan a separate set for each crude/CDU/VDU combination.

4. The streams produced in the model correspond much more closelyto streams physically produced in the refinery.

5. All vacuum yields are specified in the Assays Table, eliminating theneed to maintain vacuum yield data in VDU submodels.

SINGLE-PRODUCT LP BLENDER

Refinery blending of a cargo is done with following objectives:

1. Meet the requirement of a specific shipment with respect to volumeand product specification.

2. Optimum blending; that is, there is no giveaway on product qualityand minimum cost to the refinery.

3. Minimize the inventory of stocks by giving priority to reblendingtank heels and other unwanted stocks.

To meet these objectives, many refineries use an on-line single-productLP system. This system interfaces with the refinery's LAB system fortank test results and product specifications. The refinery on-line LABsystem records, monitors, and reports on streams and product tank testresults done by the refinery's laboratory, forming the database fora single-product LP blender.

The on-line single-product LP blender aims to provide minimum-costblends within user-defined volumetric and specification constraints, usinga linear programming algorithm. Optimization of the blend is done on thebasis of the prices of blend streams provided by the user. The LP blendersystem minimizes the cost of the blend produced while meeting productspecifications.

For the optimization step, the prices of the blend stocks must beprovided. Generally, a very low cost is assigned to stocks such as tankheels and other unwanted stocks to maximize their blending. Ifthe objective is to minimize inventory, arbitrary prices may be used; theassumed price of a stock in this case is inversely proportional to theavailable inventory.

The user enters only the tank numbers allowed in the blend, the targetspecifications, and the total blend volume required. Latest tank qualitydata, such as specific gravity, sulfur, or flash point, are retrieved from theLAB system, once the tank number is entered. The LP next works out theoptimum blend composition that meets all given specifications.

The optimum blend composition thus worked out is used for actualblending of cargoes, instead of using past experience with similar blends,manual calculations, or tedious trial and error procedures.

EXAMPLE 13-5

We want to blend 100 mb of a gasoline grade with the followingspecifications:

RON MINIMUM 95MON MINIMUM 83.5RVP kPa MAX 62.0RELATIVE DENSITY MIN/MAX 0.7200/0.775% EVAPORATED AT 700C MINIMUM 12

The blending is to be done in tank 74, which contains 8000 bbl ofpreviously shipped gasoline cargo. Determine the most economic blend,using the available stocks. The available blending components andassumed prices are as follows:

STOCK TANK NO. PRICE, $/bbl

FCCU LIGHT NAPHTHA 75 17.5FCCU HEAVY NAPHTHA 77 17.1REFORMATE 54 19.0MTBE 79 26.5COKER LIGHT NAPHTHA 72 15.6ALKYLATE 73 22.5GASOLINE (TANK HEEL) 74 15.0

Using a single-product blender system, the tank volume and propertydata are retrieved from the LAB system, which contains the latest test

results done on these tanks. The user insert only the blend componentprices for optimization calculations and the total volume of the blendrequired. The following table is the result:

TANK AVAILABLE RON, MON, RVP, % DISTILLED,STOCK NO. VOL, mb SG CLEAR CLEAR kPa 700C

FCCULIGHT 75 60.5 0.7095 93 82.7 63 51.0NAPHTHA

FCCUHEAVY 77 40.0 0.8390 93.8 83.2 0 0NAPHTHA

REFORMATE 54 20.0 0.7830 96.5 86.4 54.6 10.5MTBE 79 15.5 0.7450 112.5 100.0 56.7 100COKERLIGHT 72 25.4 0.7030 74 65.8 53.2 30

NAPHTHAALKYLATE 73 10.3 0.6845 97.8 94.5 51.8 10.0GASOLINE 74 8.0 0.7550 93 83 62.0 15.0

(TANK HEEL)

The problem is converted into an LP model as presented next. Here,T75, T77, T54, BLN, and the like are variables and their values are foundsubject to the following conditions. Find

T75, T77, T54, T79, T72, T73, T74, BLN > 0

BLN = 100

such that

T75 < 60.5

T77 < 40.0

T54 < 20.0

T79 < 15.5

T72 < 25.4

T73 < 10.3

T74 = 8.0

and the following constraints

T75 T77 T54 T79 T72 T73 T74 BLN

MAT. BAL. 1 1 1 1 1 1 1 - 1 = 0SG(MIN) 0.7095 0.8390 0.7830 0.7450 0.7030 0.6845 0.7550 -0.7200 > 0SG(MAX) 0.7095 0.8390 0.7830 0.7450 0.7030 0.6845 0.7550 -0.7750 <0RON 93.0 93.8 96.5 112.5 74.0 97.8 91.0 -95.0 >0MON 82.7 83.2 86.4 100.0 65.8 94.5 81.0 -83.5 >0RVP 63.0 0 54.6 56.7 53.2 51.8 62.0 -62.0 < 0DISTILLED, 700C 51.0 0 10.5 100.0 30.0 10.0 15.0 -12.0 <0

and such that

Y = 17.5*(T75) + 17.1*(T77) + 19.0* (T54) + 26.5* (T79)

+ 15.6*(T72) + 22.5*(T73) + 15.0*(T74) is minimum

The blend composition and properties are found on solution of thepreceding problem, as follows:

BLEND COMPONENT VOLUME, mb

LIGHT CAT NAPHTHA 41.69HEAVY CAT NAPHTHA 30.00REFORMATE 13.74MTBE 6.56COKER LIGHT NAPHTHA 0ALKYLATE 0TANK HEEL 8.00TOTAL BLEND 100.00

Gasoline blend properties are as follows:

PROPERTY SPECIFICATION BLEND

SG 0.720-0.775 0.764RON 95, MIN 95.2MON 83.5, MIN 84.8RVP 62kPa, MAX 42.5% DISTILLED, 700C 12% (VOL), MIN 30.5

NOTES

1. For example, IBM MPSX/370 or CPLEX Optimisation Inc.2. Aspen Technologies Company, originally developed by Bechtal Inc.3. J. S. Bonner, "Advance Pooling Techniques in Refinery Modeling."

Bonner and Moore Associates GmbH seminar Wiesbaden,Germany, Oct 19-21, 1987.

4. G. B. Dantzig, Linear Programming and Extensions. Princeton, NJ:Princeton University Press, 1946.

5. The LP packages from different vendors may have different row andcolumn naming conventions. The one described here is from the PIMSfrom Aspen Technology.