IO
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Transcript of IO
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INDUSTRIAL ORIENTATION REPORT
Prahasith Garimella
5TH SEMESTER
13BPE021 (U1- Group)
SCHOOL OF PETROLEUM TECHNOLOGY
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ABSTRACT
This report presents the brief account of Industrial orientation programme organised by
School of Petroleum Technology, Pandit Deendayal Petroleum University, as a part of course
curriculum of B. Tech in Petroleum Engineering. The objectives of the programme were
• To expose students to various operations of oil and gas industry for enhancing their
understanding about application of science and engineering principles studied in first two
years of B. Tech programme.
• To develop students’ understating about oil and gas industry operations to facilitate their
academic and research learning for the 3rd and 4th year B. Tech programme and to create
border understanding of oil and gas value chain.
The orientation started with the lecture series of the eminent leaders of the oil and gas
industries and research institutes who gave exposure of the happening in the industries and
what qualities we have to nurture in order to be perfect for services. This was followed by
five days visit of various industries and research institutes in order to get a complete
package of the oil and gas value aided business. Some of the industries and institutes we
visited were –
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ACKNOWLEDGEMENT
First and foremost, I sincerely thank School of Petroleum Technology, Pandit Deendayal
Petroleum University, Training and Placement team which worked hard to organise the
Industrial orientation- 2015 and provide an invaluable and incredible opportunity to learn.
I find short of words in expressing my gratitude to all the speakers from the prominent
industries that provided the exposure to understand the petroleum value chain and gave a
glimpse of ideas that would pave my path to the future. I am grateful and would like to
express my appreciation to the following people:
Mr. HCV Kumar, Vice President Technical, Tata Petrodyne who focussed on skills
required to strengthen the position in the industries.
Dr. Uttam Kumar Bhui, PhD Associate Professor, PDPU who highlighted the areas of
recent research trends in Petroleum industry.
Dr. Prem Kumar Chawla, Wireline Logging Department, ONGC- Ahmedabad who
brushed our knowledge of logging with practical overviews and also gave a brief of
various types of logging.
Ms. Yukti Jaiswal & Ms. Anjali Bhatia, IDP who outlined the career opportunities in
USA, Canada and UK after Graduation.
Mr. Sunil Parekh, Zydus Cadila who emphasised on inheriting various qualities in
order to become a true engineer.
Mr. Parasharan Chari, Endeavour who talked about career Opportunities after
B.Tech.
At last I want to appreciate all the industries (Selan, ONGC – IRS, ONGC – WSS, GSPC and
HLS Asia) to provide an opportunity to look and scrutinize the practical ideas very closely.
I would also like to spread my sincere thanks to the faculty team of PDPU who were always
with us to support, guide and bear our mischief.
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CONTENTS
Topics Page number
1. Acknowledgement 3
2. Introduction 5
3. Overview of Industrial Orientation Programme
a) Overview of lecture series
i) Mr. HCV Kumar, Tata Petrodyne
ii) Dr. Uttam Kumar Bhui, PhD Associate Professor, PDPU
iii) Dr. Prem Kumar Chawla, Wireline Logging Department,
ONGC- Ahmedabad
b) Overview of Industrial visit
i) ONGC WSS
ii) HLS Asia Limited
iii) Institute of Reservoir Studies, Chandkheda.
Ahmedabad
iv) GSPC, COCTS, Nawagam & Tarapur
v) Selan Exploration Technology Limited
7-36
4. Conclusions 37
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INTRODUCTION
Industrial orientation means to learn from an industry perspective. Its sole aim is to build a
channel between industries and institutes to outsource knowledge.
The main Objectives of the industrial orientation programme are following:
To expose students to various operations of oil and gas industry for enhancing their
understanding about application of science and engineering principles studied in first
two years of B. Tech programme.
To develop students’ understating about oil and gas industry operations to facilitate
their academic and research learning for the 3rd and 4th year B. Tech programme.
To create border understanding of oil and gas value chain.
To expose students to upstream, midstream and downstream operations of oil and
gas sector.
As an upstream I have to cater the demands of the industries so I must have an
exposure of all the discipline underlying upstream like
Exploration, I have to
• Understand and explain fundamental principles and mechanisms of Exploration.
• Aerial and geophysical surveys
• Geological studies
• Employ appropriate measurement methods to assess volume and relative
production of hydrocarbon reserves.
In Drilling, I have to
• Understand and explain fundamental principles and mechanisms of drilling.
• Explain the techniques of evaluating different petroleum formations.
• Core testing and drilling of well.
• Understand and explain concepts of porosity, permeability, wettability, and
capillary pressure. Understand how these parameters may affect the oil production.
In Production, I have to understand
• Well and Reservoir Pressures
• Well testing
• Cased-Hole Logs
• Production Logs
• Well stimulation
• Surface Subsidence
The duration of industrial training was of 10 days from 1 July,2015 to 10 July, 2015 which
comprised of 5 days lecture series and 5 days of industrial visit.
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In the first five days, career counselling sessions were organized where students were
acquainted with various job opportunities in the Oil and Gas Industry in India as well as
abroad. Various dignitaries of the field visited the universities to deliver these lectures. It
was followed by distinguish lecture series of industries men who briefed about various
prospects needed to acquire in order to get into the industries. The students were also
enlightened about pursuing careers in research fields, entrepreneurship and industry
expectations, as well as dedicated sessions on career opportunities in the Upstream and
Downstream sector.
In the last five days, the students visited various industries from the Upstream and
Downstream sector, one industry each day of the week. They were given the opportunity to
interact with field professionals and engineers, and saw various company assets such as gas
processing terminals, Christmas tree and separator manifold etc. A detailed description of
each industrial visit is outlined in the next pages.
Schedule of the Industrial Visits
Name of the
Industries/Institutes
Date visited
ONGC WSS( Well Simulation
Services)
1 July,2015
HLS Asia, Gandhinagar
3 July,2015
ONGC IRS – Institute of Reservoir
Studies, Chandkheda. Ahmedabad
6 July,2015
GSPC, COCTS, Nawagam & Tarapur
9 july 2015
Selan Exploration Technology ltd.,
Bakrol 10 July,2015
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Overview of Industrial orientation programme
1. Overview of lecture series
1. Mr. HCV Kumar, VP Technical, Tata Petrodyne
He made us aware of Tata Petrodyne and its Exploration & Production Operations.
Various important industry software’s - Petrel, Kingdom
Why oil prices fluctuate and factors governing them.
He introduced us some new terms – sunk money, pre-salt deposits.
Skills and qualities needed to strengthen our position, when in the industry.
Scope of production and operation management
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Open Hole Logging
Gamma ray logs
SP (Spontaneous potential) logs
Caliper logs
Density logs
Neutron logs
Resistivity logs
Sonic logs
Cased Hole Logging
Well bore integrity
Fluid movement
Cased hole operations
Casing collar locator
Cement bond tool
Perforation
Production Logging
Radioactive fluid density tool
Production gamma ray tool
Capacitance temperature flowmeter
2. Dr. Prem Kumar Chawla, Wireline Logging Department, ONGC- Ahmedabad
Gave a brief of logging types
Cased Hole Operations
CASING COLLAR LOCATOR
The CCL detects casing collars and perforations in tubing and casing.
DESCRIPTION
The CCL is a magnetic device that detects changes in metal mass, such as those induced by
the relatively high mass of a casing collar Vis-a Vis the casing. The disturbance to the
magnetic field is detected as a voltage difference. The CCL detects changes in metal volume
as it moves through tubing or casing. The tool detector is comprised of a coil mounted
between two opposing permanent magnets. As the tool passes a collar, the lines of
magnetic flux between the magnets are disturbed, inducing a low frequency voltage in the
coil. The signal is amplified and gated onto the wireline.
PURPOSE
To determine the location of casing collars.
APPLICATIONS
Depth correlation.
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CEMENT BOND TOOL
CEMENT & ISOLATION
The main purpose of cement over the production interval is to provide isolation between
neighbouring zones. Failure in isolation can cause problems like water production, depletion
of gas drive mechanism, loss of production to neighbouring zones, Contamination of fresh
water sands etc. The remedy, is to squeeze cement job but
It is not much benefit.
DESCRIPTION
The CBT evaluates cement bond integrity. The tool typically has a single Omni directional
acoustic transmitter and two receivers. One receiver at three feet and another receiver at 5
feet. The tool has no azimuthal capability; instead the received signal is an average from all
around the pipe.
PRINCIPLE
The CBT measures based upon the principle of sonic wave train attenuation, detecting the
amplitude of a sonic signal passing along the casing as an analog waveform. The signal is
reduced where the the casing is bonded to the cement, clearly identifying cement bond. The
primary amplitude is detected at 3 feet receiver and variable density log is generated at 5
feet receiver.
PURPOSE
Cement bond integrity is requisite to hydraulic isolation.
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APPLICATIONS
Cement bond evaluation.
PERFORATION
To establish fluid communication between well bore and formation for production /
injection. It uses high explosives with shaped charges.
Perforator’s uses
Initiator / detonator
Detonating chord
Shaped charges
The two types of perforations are
Over balanced method (+Ve head).
Under balanced method (-Ve head).
The positive head is achieved by keeping higher density mud in the borehole as compared to
formation pressure. The advantage is it is easy to handle the well during perforation.
The negative head is achieved by keeping lower density borehole fluid compared to
formation. The advantage of the well is it can be straightway connected to the production
pipeline. However caution is exercised to avoid blowouts.
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BRIDGE PLUG SETTING BY WIRE LINE
Bridge plug are mainly used for isolation o zones in casing. This prevents the movement of
fluid from either direction.
PRODUCTION LOGGING
Production logging provides down hole measurements of fluid parameters on a zone
by Zone basis to yield information on the type of fluid movement within and near
the well bore.
Major applications of production logging include.
Evaluating completion efficiency.
Detecting mechanical problems , breakthrough, coning
Monitoring and profiling of production and injection
Detecting thief zones, channelled cement.
Single layer and multilayer well test evaluation.
Identifying reservoir boundaries for field development
RADIOACTIVE FLUID DENSITY TOOL
PRINCIPLE
The density tool responds to the electron density of the fluid in the bore-hole. It is used to
differentiate the various types of fluids in the bore-hole depending upon their densities.
This tool measures borehole fluid density by radioactive technique. Part of the fluid flow
passes through the tool between low activity Cs 137 gamma source and a Scintillation
gamma ray detector. An increase in the average fluid density in the sample volume causes a
reduction in received counts.
PURPOSE
The purpose of the FDR is to measure fluid density of a sample as it flows through the tool.
The average density of this volume is measured whether the flow is single or multiphase.
APPLICATIONS
Multiphase production drilling
Fluid identification
Horizontal /highly deviated wells
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High fluid flow rates.
PRODUCTION GAMMA RAY TOOL
CONFIGURATION AND PRINCIPLE
The production gamma ray tool comprises a sodium iodide scintillation crystal and
photomultiplier to measure incident gamma radiation. The single conductor passing through
the tool carries telemetry and power. The detector is unshielded and will thus accept
radiation from any direction.
PURPOSE
Lithology identification
Depth correlation
Identification of radioactive scale, possible sign of water entry.
Monitoring of radioactive flow tracer.
Gravel pack density monitoring .(With addition of gamma source)
Evaluation of shale volume.
Delineation of nonradioactive mineral including coal beds.
It can be run in both open and cased hole.
CAPACITANCE TEMPERATURE FLOWMETER
The sondex capacitance water hold up, temperature, flowmeter tool (CTF) provides these
three basic Production logging measurements within a short tool length. In the case of
standard tools the equivalent three sensors will be at least six times further apart and so in
heterogeneous flow are less likely to be providing measurements within the same fluid
simultaneously.
PURPOSE
To provide a continuous log of fluid capacitance (water hold up), Temperature, Flow rate
and flow direction.
APPLICATION
Fluid composition from average dielectric constant.
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2. Overview of Industrial visit
Accompanying by: Mr.Manan Shah
Selan Exploration Technology Limited,
EPS, Bakrol, Gujarat
General Information
Field Name Bakrol
Current Activity Status Under infill drilling and production
Area(sq. km) 36
Date of Signing Contract 13-Mar-1995
Effective Date 13-Mar-1995
Current Consortium SELAN EXPL. TECH. LTD. -100
Petroleum System
Field Name Bakrol
Reservoir -
Trap Stratigraphic
Drive Depletion
Source Cambay Shale
Cap/Seal Tarapur Shale
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Development Wells
Wells Status
BAKROL # 18
Yearly Production
Year Oil('000T) Gas(mm3)
2014-2015 13.501649 6.355965
2015-2016 1.145854 0.729099
Transportation Facilities
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CPF OPERATIONS Compressed from Off gas compression -
unit
Crude oil from well (30 kg/cm3) (8 kg/cm3)
(30 kg/cm3)
Water from Bottom KOD (knock-out drum)
Effluent treatment plant
Fractionation
Lean gas
Low Pressure Separator
1st stage separator
Medium pressure Separator
2nd stage separator
3rd stage separator
CFU - Crude Fractionation Unit ONGC
High pressure
separators
Medium pressure separator
Low pressure separator
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Review of Operations (2014-15)
Production Sharing Contracts (PSCs) with the Government of India were signed by SELAN
in 1995 for Bakrol, Indrora and Lohar oilfields. Further, the Company was also awarded
Contracts for the Karjisan Gas field and the Ognaj Oilfield with the Ministry of Petroleum and
Natural Gas (MoPNG) in 2004.
The operations of the Company continued in a smooth and uninterrupted manner during the
course of the year. The drilling campaign of the Company was in progress during the year,
with new wells drilled in the Bakrol and Indrora fields. Efforts were also ongoing to increase
higher production volumes from wells recently drilled, as new data analysis opens greater
opportunities. In terms of assessment of the complex geology formations at different depths
in our oil and gas fields, the Company continued to push the limits of technical options and
challenges with various service providers. Simultaneously, the Company was fully engaged
on all aspects of well design and completion strategies with consulting firms in North
America.
As is the case with all the Oil Companies worldwide, the dramatic decline in oil prices has
affected the revenues of the Company. With this significant drop in oil prices internationally
during the year, the Company continues to monitor its expense commitments more closely
than ever before, to ensure that profitability levels remain the highest possible under these
challenging circumstances.
Some facts learnt
In Bakrol field – Selan has 28 wells–4 self producing, rest either on srp or abandoned.
Wells BK2 & BK3 are connected to the EPS.
BK3 has 2-3 m3 per day production with 30% oil and 70% water.
The pay zone is at 1500m while depth of well is 2000m.
Pay zone comprises of sand+claystone and Hydro-Fracturing is needed in all wells.
The oil is heavy (32-35 API) with wax deposition, a major problem.
From EPS, through tanker oil is sent to CTF where ONGC measures water cut, which
must be <5% to be approved.
Supply of oil at the end of processing is done to IOCL refinery, Baroda.
Production shrinkage depends on composition.
Feed = 5 m3 = 4 m3 product + 1 m3 of (Naptha+LPG)
Colour of pipes-
Green- Water Line
Yellow – Gas Line
Red – Fire Line
Silver – Oil Line
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Institute of Reservoir Studies,
Chandkheda, Ahmedabad
Group: U-2
Accompanying Faculty: Dr. G.S.Negi
Introduction:
Institute of Reservoir Studies (IRS) originated in 1978 as an R&D institute of reservoir
management of Indian oil fields. With the passage of time, IRS has matured into a premier
institution providing complete reservoir engineering services for in house as well as external
agencies.
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The main areas of focus at IRS are Reservoir Characterization, EOR process and Well
Productivity Enhancement. To conduct tests and research IRS has the following state of art
laboratories:
• MEOR Lab
• Thermal Process Lab
• Water Flood Lab
• Petro physical lab
• Probe Centre
• Thermodynamics (PVT) Lab
• Chemical flood lab
• Tracer Lab
Objective:
The purpose of our visit was to enhance our knowledge of the oil & gas sector by having a
practical experience and to get informed about the various techniques deployed for the
extraction of the crude oil.
. Thermal Process Lab (Air injection technique):
Air injection technique is one of the unique ways in Enhanced Oil Recovery methods. Special
equipment for the testing of this process is available only at the University of Calgary,
Canada and Institute of Reservoir Studies (IRS).
Thermal enhanced oil recovery technology is particularly steam flood technology. It is widely
using in U. S. and it is an important source of domestic crude oil supply. This lab caters to
fields producing heavy oils but of late, this lab is also catering to the fields producing light
crudes.
Thermal enhanced oil recovery techniques are of four types:
• Steam
• In situ combustion
• Cyclic steam
• Huff-puff
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We were explained the processes of In-situ Combustion and Steam Injection:
In-situ combustion process:
In-situ combustion is a thermal recovery technique in which heat is produced within the
reservoir to reduce the viscosity of the otherwise heavy to very heavy crude oil. Combustion
is sustained by continuous air injection. High temperature during burning causes the lighter
fractions of oil ahead of the flame front to vaporize leaving a heavy residual coke or carbon
deposit as fuel to be burned. These vaporized light components and steam are carried
forward until they condense upon contacting cooler portions of the reservoir. The flame
front moves forward through the reservoir only after burning all the deposited fuel.
Applications of in-situ combustion are applicable to reservoirs having high viscosity crudes.
Oil content>700bbl/ (acre feet) is required for the process to be economically viable
because large amounts of crude may be burnt during the process. Drawback in in-situ
combustion is that large amount of crude is burnt during the process.
Steam Injection:
The past EOR field experiences in the world shows that steam is the most popular agent for
more oil recovery from unconventional (heavy) oil reservoirs. This apparatus is specially
designed to conduct steam injection in a long fractured model while it is assisted by gravity
drainage. The flexibility of the system would allow for any gas injection in fractured rocks
such as CO2 and N2 injection as well.
We were shown a case study also:
IRS had a success story in the Balol, Lanwa and Santhal fields, in which in-built steam
generator was used. The Balol field had a primary recovery of 10-15%. After applying in-situ
combustion, the recovery increased up to 50%.The Balol field has the following
specifications:
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• Permeability: 1-8 Darcy
• Porosity: 25-30%
• Depth: 1000m
• Reservoir temperature: 70˚C
Process of Thermal Eor.
2. Water Flood Lab:
In Water flooding some problems like scaling, precipitate formations, corrosions in pipes,
linkage due to impurities etc. in water are faced. Water quality studies are carried out at the
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Water Flood Lab. The water to be used should be compatible with the reservoir rocks and
also the reservoir fluids so tests need to carried out to ascertain the properties and suggest
measures to avoid the above mentioned problems.
Following studies are carried out:
Displacement Efficiency Studies
Physic - chemical Characterization of Injection Water
Screening & Evaluation of Water Treatment Additives & Solvents to reduce
Residual Oil Saturation
Sensitivity of Reservoir Rocks, Injection Water Treatment Design.
The corrosive nature of water is observed by putting the injected water in contact with the
tubing or tubular (N-80 is the currently used tubular). The tubular is kept at desired
temperature i.e. the well bore temperature, then the initial and final weights of the tubular
are measured and finally we get the corrosion rate of injection water.
Also some fluid displacement studies were explained to us. Core samples were shown with
special core holders and also the experiments were explained in which the reservoir
conditions like pressure, temperature and saturation were simulated and the displacement
tests can be carried out to understand the performance of water flooding in the oil field of
interest
3. Petro physical lab:
In the petro physical lab we study of physical properties of rocks like Permeability, porosity,
density and fluid saturation.
We were explained the basic concepts of relative and absolute permeability, capillary
pressure and wettability.
Relative permeability is the ratio of effective permeability of a particular fluid at a particular
saturation to absolute permeability of that fluid at total saturation.
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Absolute permeability is the measurement of the permeability conducted when a single
fluid, or phase, is present in the rock
Capillary Pressure:
When oil & water are placed together on a surface, a discontinuity in pressure exists across
the interface separating them. This difference in pressure in known as Capillary Pressure.
Wettability:
Tendency of fluid to spread on a solid surface in the presence of other immiscible fluid is
termed as its wettability.
We were also shown a lot of core samples and how they are used to determine petro
physical properties. We were explained the procedure to measure porosity and
permeability.
4. Tracer Lab:
Tracer lab is important because the resolution of seismic data is too low to see any
meaningful detail that would help to explain the fluid flows. Core data and log data
generally cover very little portion of the reservoir. As for example heterogeneities in a two
inch core plug were not representatives with the several thousand ft. of inter well distance
in the reservoir.
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Tracing of injection fluids:
Benefits of tracer lab: Preferential flow directions, Horizontal and vertical communication
between wells, Permeability strata, Sweep volumes and Large-scale heterogeneities.
In the Tracer Laboratory we design, execute, and monitor tracer survey programs. Inter-
Well Tracer Test (IWTT) and Single- Well Chemical Tracer Test (SWCT) are two powerful
techniques for obtaining accurate picture of the reservoir.
Inter-Well Tracer Tests (IWTTs):
In the IWTTs determining the directional permeability trend and identifying flow barriers,
evaluating the sweep improvement treatments and monitoring the injected fluid front in
reservoir.
In monitoring collection of produced fluid (water/gas) samples from each monitoring well at
regular intervals. Analysis of samples, generation of tracer profiles and interpretation of
data in conjunction with field data.
Tracer’s types:
Ammonium Thiocynate
Sodium chloride
Titrated water H3
Sulphur hexa fluoride
Single-Well Chemical Tracer Test Technique:
• It is useful for measuring residual oil saturation (Sor) of the designated
discrete horizon after water flood.
• This technique is based on chromatographic separation of chemical tracers.
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• It relies on the determination of retardation factor of a chemical tracer
(ester), which partitions between oil and water phases in reservoir.
• It helps to assess the feasibility of tertiary EOR programme.
• In-house capabilities have been generated at IRS for designing and
implementation.
• A larger area/volume of the reservoir is covered as compared to other
conventional methods for Sor measurements like core analysis and well logging.
Generally it is used in water flooded reservoir and Inject ethyl acetate or propyl acetate
depending upon the suitability of the reservoir. Inject water to push the tracer as much as
possible to cover large area. Close the well for two/three days depending upon the kinetics
of the tracer in reservoir condition days.
PROCEDURE OF THE TEST
Inject a ~1-pore volume pre-flush of brine to ensure oil saturations are at waterflood
residual over the test volume (typically a 10-15 foot radius from the wellbore)
Inject ester tracer into zone of interest.
Push the ester slug away from wellbore and into the formation with brine.
Shut-in well to allow the ester in the water phase to hydrolyse into an alcohol.
Produce the well back and continuously sample and measure concentrations of
produced chemical tracers, both the ester and produced alcohol.
Determine Sor from measured separation of ester and produced alcohol and
simulate results.
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K - partition coefficient (fraction of ester in oil to fraction of ester in water) β -
retardation factor relating the differences in velocity or transport between the
alcohol and ester
Sor - residual oil saturation to water flood or EOR process.
5. Gas Injection Lab
Gas injection or miscible flooding is presently the most-commonly used approach in
enhanced oil recovery. Miscible flooding is a general term for injection processes that
introduce miscible gases into the reservoir. A miscible displacement process maintains
reservoir pressure and improves oil displacement because the interfacial tension between
oil and water is reduced. This refers to removing the interface between the two interacting
fluids. This allows for total displacement efficiency. Gases used include CO2, natural
gas or nitrogen. The fluid most commonly used for miscible displacement is carbon dioxide
because it reduces the oil viscosity and is less expensive than liquefied petroleum gas. Oil
displacement by carbon dioxide injection relies on the phase behaviour of the mixtures of
that gas and the crude, which are strongly dependent on reservoir temperature, pressure
and crude oil composition.
Principle:
Vaporising ( C2 – C6 transfer from oil to gas )
Condensing ( C2-C6 transfer from gas to oil )
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Immiscible CO2-EOR occurs when insufficient reservoir pressure is available or the
reservoir's oil composition is less favourable (heavier). The main mechanisms involved in
immiscible CO2 flooding are: (1) oil phase swelling, as the oil becomes saturated with CO2;
(2) viscosity reduction of the swollen oil and CO2 mixture; (3) extraction of lighter
hydrocarbon into the CO2 phase; and, (4) fluid drive plus pressure. This combination of
mechanisms enables a portion of the reservoir's remaining oil to be mobilized and produced
(details of these mechanisms are discussed later in this paper). In general, immiscible CO2-
EOR is much less efficient than miscible CO2-EOR in recovering the oil remaining in the
reservoir.
Swelling of Oil: The swelling of oil due to CO2 dissolution is important for two main
reasons. Firstly, the residual oil left in the reservoir after flooding is inversely
proportional to the swelling factor, i.e. the greater the swelling, the less stock tank
oil abandoned in the reservoir. Secondly, disconnected oil blobs may become
reconnected as the oil swells and forces water out of the pore space. This creates
higher oil recovery and more favourable relative permeability curves at any
saturation condition.
Viscosity Reduction: This reduction, like heating of oil in thermal recovery, can yield
viscosities one-tenth to one-hundredth of the original oil viscosity. The magnitude of
viscosity reduction is greater in heavier oil samples.
Oil Extraction: At high pressure conditions, in addition to CO2 dissolution into the oil
phase, light and intermediate hydrocarbon components may be vaporized into the
CO2 and recovered. This extraction may also result in very low interfacial tensions
(IFT) and consequently reduction of residual oil saturation.
Solution Gas Drive: Just as CO2 goes into the solution with an increase in reservoir
pressure, after termination of the injection phase of flood, gas will come out of the
solution and continue to drive oil into the wellbore.
6. MEOR lab –
Ageing of wells and unproductive wells are a perpetual and crucial concern that the global
oil industry faces. An oil well becomes sick when approximately 30% of oil in place has been
recovered. These so-called dead or sick well still have a substantial quantity of oil left in
them. Conventional methods of recovery are extremely expensive and task challenging due
to a significant change in the reservoir conditions.
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Microorganisms can thrive in these adverse conditions and assist in enhancing oil recovery,
a process called Microbial Enhanced Oil Recovery (MEOR). MEOR is a tested and increasingly
applied method of oil treatment in the industry. The microbial well treatment processes fall
into three basic applications: well bore clean up, improved water flooding (bypass
treatment increases sweep efficiency), and well stimulation.
The MEOR process involves injecting microbes along with nutrients into the well and closing
it for approximately 20 days. The bacteria, cultured to thrive in anaerobic conditions
propagate and produce polymers, gases, surfactants and organic acids. The bacteria aids in
retrieving oil with a two-pronged approach, one, by bringing about a change in the physical
properties of the rock, and two, in the crude itself. The surfactant, acid and solvents clean
out the paraffin wax and the heavy crude depositions in the pores of the rock, thus
improving the porous character of the rock. The surfactant also lowers the interfacial
tension between reservoir fluids and residual oil to ease the displacement of the oil. On the
other hand, bacteria reach deep pores where no other medium can reach. They then act
upon the oil and reduce its thickness in the reservoir and thus aid in its free flow. The gases
that it produces, carbon dioxide and methane, restore the gas drive quality of the oil
pushing it to the mouth of the well.
Advantages of MEOR treatment:
Increase Oil Recovery Factor and thus life of the field is extended for years.
Reduce production declines.
Cost reduction on the well abandonment, as these wells can be turned to production
economically.
Increased water flooding efficiency.
Decreased water cut, significantly improves oil production and cash flow.
A simple operation which can be implemented on small pilot area of 5-10 wells.
Utilizes indigenous microorganisms, environmentally friendly and no harsh chemicals
or additives used.
Results can be realized within 2-3 weeks after the treatment.
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7. Thermodynamics lab
In thermodynamic lab I saw so many apparatus for PVT analysis of crude oil
Bottom hole sampler
GCMS
Cryoscope to find the molecular weight
Autopar to measure the torque
SARA analysis
Constant mass expansion cell
Density meter
Auxiliary cell
8. Chemical flood lab
To study the chemical eor this lab is used to develop the surfactant
Chemical EOR is the optimization of injection water by adding a chemical or fine-tuning the
chemistry. There are four types of chemical EOR:
Polymer flooding where the injection-water is made more viscous in order to push the crude
from the injection- to the producing well. This type of EOR is mostly used with crude that
have a higher viscosity.
Surfactant flooding where a “soap” is pushed through the reservoir to get remaining oil
droplets out of the pores by reducing the surface tension of the droplets. This creates a
micro-emulsion which increases the mobility of the crude. The soap can be the surfactant or
created as petroleum soap by alkali. The chemical cocktail is stabilized by polymer hence the
name Alkali Surfactant Polymer (ASP) flooding.
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GSPC, COCTS, Nawagam & Tarapur
Accompanying by: Ms. Shreya Shejpal
GSPC TARAPUR
A total of 12 discoveries have been made. One discovery (Tarapur-1) has been developed
into the Tarapur-1 Producing Field. Two discoveries, namely Tarapur-6 & Tarapur-G have
been lined up for government approval for the full-scale development of an oil and gas field
respectively. The remaining discoveries have been commercially evaluated and the relevant
reports are under examination by the regulatory body (DGH). The block awaits permission
for the extension of the exploration period to 18 months in order to carry out enhanced
exploration opportunities. Engagement of internationally reputed firms is in process for
introduction of new technologies to enhance production.
Oil and gas separator:
A cylindrical or spherical vessel used to separate oil, gas and water from the total fluid
stream produced by a well. Separators can be either horizontal or vertical. Separators can
be classified into two-phase and three-phase separators (commonly called free-water
knockout). The two-phase type deals only with oil and gas, while the three-phase type
handles oil, water and gas. Additionally, separators can be categorized according to their
operating pressure. Low-pressure units handle pressures of 10 to 180 psi [69 to 1241 kPa].
Medium-pressure separators operate from 230 to 700 psi [1586 to 4826 kPa]. High-pressure
units handle pressures of 975 to 1500 psi [6722 to 10,342 kPa]. Gravity segregation is the
main force that accomplishes the separation, which means the heaviest fluid settles to the
bottom and the lightest fluid rises to the top. Additionally, inside the vessel, the degree of
separation between gas and liquid will depend on the separator operating pressure, the
residence time of the fluid mixture and the type of flow of the fluid. Turbulent flow allows
more bubbles to escape than laminar flow.
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Stage separation:
An operation in which the well stream is passed through two or more separators that are
arranged in series. The first separator is called first-stage separator, the second separator is
called second-stage separator and additional separators are named according to their
position in the series. The operating pressures are sequentially reduced, so the highest
pressure is found at the first separator and the lowest pressure at the final separator. The
objective of stage separation is to maximize the hydrocarbon liquid recovery and to provide
maximum stabilization to the resultant phases (liquid and gas) leaving the final separator.
Stabilization means that considerable amounts of gas or liquid will not evolve from the final
liquid and gas phases, respectively, in places such as stock tanks or gas pipelines.
Additionally, stage separation reduces the horsepower required by a compressor, since the
gas is fed at higher pressures.
Storage tanks: A tank designed for storing volatile liquids such as gasoline and liquefied
petroleum gases (LPG), which generate high internal pressures. A pressure storage tank is
commonly spherical. Other types include spheroidal or hemispherical vessels. Some
pressure storage tanks can support several hundred pounds per square inch of internal
pressure. A pressure storage tank is also called a pressure-type tank.
Christmas tree:
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An assembly of valves, spools, pressure gauges and chokes fitted to the wellhead of a
completed well to control production. Christmas trees are available in a wide range of sizes
and configurations, such as low- or high-pressure capacity and single- or multiple-
completion capacity.
Christmas trees are used on both surface and subsea wells. It is common to identify the type
of tree as either "subsea tree" or "surface tree". Each of these classifications has a number
of variations. Examples of subsea include conventional, dual bore, mono bore, TFL (through
flow line), horizontal, mudline, mudline horizontal, side valve, and TBT (through-bore tree)
trees.
Crude oil loading station of GSPC
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HLS Asia Limited (HLSA, Gandhinagar)
ACCOMPANING BY: Ms. Vaishali
On this day we went to HLS Asia. Firstly we were welcomed by the security officer and he
introduced us to the safety practices and standards of the company and the work HLS is
handling in Gujarat.
Following this we had a complete tour of HLS premises, where we were taken to, and
briefed about various logging tools and the logging truck by a senior engineer.
Open Hole Services
RESITIVITY ACOUSTICS
High Resolution Array Induction Tool (HRAI)
High Resolution Induction Tool (HRI)
Dual Laterolog Service (DLL)
Array Compensated Resisitivity Tool(ACRT))
Micro-Spherically Focused Log (MSFL) and Microlog (ML)
WaveSonic Tool
Full Wave Sonic Tool (FWS)
Circumferential Acoustic Scanning Tool(CAST)
Borehole Compensated Sonic Array Tool (BSAT)
Borehole Compensated Sonic-DITS Tool (BCDT)
IMAGING AUXILIARY SERVICES
XRMI
Circumferential Acoustic Scanning Tool-Visualization
Releaseable Wireline Cable Head (RWCH)
Toolpusher (TPL)
Four Independent Arm Caliper (FIAC)
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OMRI Brochure
Six Arm Dipmeter (SED)
Stand-Alone DITS Directional Tool (SDDT)
NUCLEAR SAMPLING
Spectral Density Log (SDL)
Dual-Spaced Neutron II Tool (DSN II)
Compensated Spectral Natural Gamma Ray (CSNG)
GEM Elemental Analysis
Natural Gamma Ray Tool (NGRT)
Reservoir Description Tool (RDT)
MRILab Service
Sequential Formation Tester IV (SFT-IV)
Sequential Formation Test Tool (SFTT)
Rotary Sidewall Coring Tool (RSCT)
Side Wall Coring Tool (SWC)
MRI
Magnetic Resonance Image Logging Tool (MRIL-Prime)
MRILab Service
Cased Hole Services
FORMATION EVALUATION PERFORATING SYSTEMS
Thermal Multigate Decay-Lithology Logging Tool
Reservoir Monitor Tool (RMT Elite)
Spectra Flow Logging Service (SpFl)
Dyna-Star Capsule Gun
Deep Star Perforating System
StimGun
Ported Gun Perforating System
Scallop Gun Perforating System
Tubing Conveyed Perforating System
PIPE RECOVERY SERVICES CEMENT EVALUATION
Chemical Cutter
Tubing Cutters
Casing and Drillpipe Cutters
C-4 Casing Cutters
Circumferential Acoustic Scanning Tool-Visualization
Cement Bond Log (CBL)
PRODUCTION LOGGING CASING EVALUATION
Production Logging Tools Circumferential Acoustic Scanning Tool-
Visualization
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Logging Truck
Length and Weight
Compared to the previous generation quad–combo, the LOGIQ downhole toolstring is about half the length and about two thirds the weight. The smaller dimensions make the equipment far safer to handle, and they contribute not only to faster rig up and rig down times, but also to the elimination of excessive rig time needed to drill long “rathole” sections. Premium Service Specifications Unlike other toolstrings touted for being “shorter and lighter,” LOGIQ tools can handle a full range of downhole challenges. All LOGIQ tools are rigorously qualified to 350ºF and 20,000 psi, thus preserving operational flexibility for the customer.
Downhole Communication
The LOGIQ system utilizes an Ethernet communication protocol that produces a five fold increase in data capacity between downhole tools and the surface system. Benefits of the new protocol include faster logging speeds, the ability to combine current generation high data rate tools, and the provision for future, even higher data rate tools.
Flexible
While the LOGIQ platform offers all new primary sensors, there are circumstances where customers may want to run previous generation downhole logging tools. The LOGIQ system easily accommodates these older tools, including and encompassing any of the open-hole logging tools in the Halliburton fleet. Tools may be used in virtually any combination and in virtually any order on the toolstring.
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Field Maintenance and Job-ready Status
The LOGIQ system was developed with a keen eye towards fast, efficient field maintenance of all downhole and surface equipment. Parts commonality, an advanced supply and support chain, and superior mechanical and electrical engineering contribute to maximum field worthiness and job–ready status for the customer. This subtle but critical aspect of operational efficiency can be especially important when advance job notice is impossible for the customer.
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ONGC Well Stimulation Services (WSS)
ACCOMPANING BY: Dr. Uttam Bhui
Introduction:
ONGC Well Stimulation Services (WSS) originated in 1975, when a central stimulation team
was formed for conducting Hydraulic Fracturing (HF) operations. HF is usually done to
overcome skin or scale in the formation along with increasing permeability of the formation.
FracPro is the industry software used for simulation of fracturing operations, while RealPro
and AccuFrac are used for Fracture Monitoring. Since its start, WSS has always been part of
the crisis management team of ONGC especially in case of a blowout.
Oilfield Services:
1. Hydraulic Fracturing
2. Acidisation
3. Sand Control
4. Coiled Tubing
5. Nitrogen Application
6. Laboratory Studies
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Facts Learnt:
Different grades of proppants are available according to fracture closure
pressure – low strength proppant(upto 5000psi), intermediate strength
proppant and high strength proppant(upto 10000psi)
Most frequently Guar Gum is viscosifier for Frac. Fluid, otherwise proppants
would settle down. Also cross-linker polymer is mixed in the Frac. Fluid for
efficient carrying of proppants.
Slick water frack is used for shale. In shale fracturing, proppant concentration
needed is less so water concentration needed is very large.
Currently WSS is carrying out pilot phase hydraulic fracturing study along with
Conoco Phillips for shale gas prospect in Tarapur-Cambay Shale formation in
Jambusar, Gujarat.
One major reason for low development of shale gas projects in India is that
Indian Shale has more clay content than US Shale, so clay swelling is a major
concern
Learning from the visits/ Conclusion:
Industrial Orientation was an opportunity to broaden our understanding of the
industry and experiencing the practical application of theories learnt in the class.
Early-production facilities (EPFs) can help operators bring their new discoveries
onstream fast. Selan Exploration visit made us aware about the Early Production
System (EPS). Operators can begin production early while full field development is
being planned and permanent facilities are being built.
The visit to the Institute of Reservoir Studies (IRS) was really a very informative and a
great learning experience. The laboratories we visited were Thermal process, Water
Flood, Petro physics Lab and the Tracer Laboratory. In the primary recovery process
generally 15%-20% oil is recovered on an average. So in the secondary process some
percentage of oil also recovered by employing different enhanced oil recovery
method. The eight different labs of this institute helps in this process in knowing the
reservoir and fluid characteristics and then employing the suitable EOR method for
secondary recovery.
During GSPC visit, we got to experience the facets of a Crude Oil Custody Transfer
Station (COCTS). Crude from two different stations i.e. Ahmedabad and Tarapur
block is brought by tanker and here its custody is transferred to ONGC CTF using
pipelines.
In HLS Asia premises in Gandhinagar, we got to see real logging tools which we had
been studying in class. Also we understood the working of a Logging Truck and how
actually a Formation Evaluation Job is conducted in field.
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This Industrial Visit has given me an overview of the industry to build my career in a
proper direction and it will help me to choose right industry in future.