1. Adnan hatim nek
MECHANICAL (FINALYEAR)
NEDUNIVERSITYOFENGINEERINGAND
TECHNOLOGY
INTERNSHIPREPORT
PAKISTAN PETROLEUM LIMITED

2. (SUI GAS FIELD) INTERNSHIPREPORT
ADNAN HATIMNEK 1
Table of Contents
S.no. Title Page no.
01 Acknowledgement 02
02 Sui Field Gas Compression Station SFGCS 03
03 Introduction 03
04 QHSE 03
05 Administration 03
06 Planning 03
07 Operations and Machinery 03
08 Workshop 05
09 HVAC system 05
10 Electrical 06
11 PURIFICATIONPLANT 06
12 Introduction 06
13 Instrumentation 06
14 Power house 06
15 Water treatment 07
16 Operations 07
17 Gas sweetening and gas dehydration process 07
18 Maintenance 08
19 PRODUCTIONFACILITIES 09
20 Introduction 09
21 Cathodic protection 09
22 Drilling at Well 95 10
23 SUL dehydration plant 10
24 Well operations 10

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ADNAN HATIMNEK 2
ACKNOWLEDGEMENT
The whole praise is to Almighty ALLAH, creator of this universe. Who made us the
super creature with great knowledge and enable us to accomplish this task.
The internship opportunity I had with Pakistan Petroleum Limited was a great chance
for learning and professional development. Therefore, I consider myself as a very lucky
individual as I was provided with an opportunity to be a part of it. I am also grateful
for having a chance to meet so many wonderful people and professionals who led me
though this internship period.
I would also like to express my deepest gratitude to all the Technical and Management
staff of Pakistan Petroleum Limited for their excellent guidance, caring, patience, and
providing me with an excellent atmosphere for internship. The supervision and support
that they gave truly help the progression and smoothness of the internship program.
The co-operation is much indeed appreciated.
This internship as an integral part of B.E provides the opportunity of peeping into real
professional life of the engineers. It enables me to evaluate and understand the
practical applications of all the terms and techniques that we have studied during our
coursework and has helped me in my professional growth by getting used to the
working environment of a field.
I was assigned to complete my internship comprising of 4 weeks practical work at
PAKISTAN PETROLEUM LIMITED (PPL) SUI GAS FIELD. In this report I have tried my
level best to explain what I have learned during this internship program.

4. (SUI GAS FIELD) INTERNSHIPREPORT
ADNAN HATIMNEK 3
SUI FIELD GAS COMPRESSION STATION (SFGCS)
Dated: (19th
may – 28th
may)
INTRODUCTION:
Due to the continuous decline of wellheadpressure andthe rise in the Gasdemandof the countrythe need ofcompression
plant becomes inevitable. The Sui Field Gas Compressor Station was establishedin1983 in two phase. 2 stage compression
is required due to the constant decreasing pressure from the wells. Their target is to provide the purification plant the
pressure of 60-65 bars while taking the pressure of 15-16 bars nowadays.
It is one of the biggest Gas Compression Station of Pakistan.
QHSE: (Quality Health Safety and Environment)
In the QHSE section of Purification Plant at Sui Gas Field, we were welcomed byEngr. Umer. He told us all about the safety
and the policies that PPL is currentlyfollowing. He alsoarranges the PPEs (Personal Protective Equipment)for us andgave
us a set of useful instructions that must be followed during the field to ensure safety. He also gave us our schedule of the
induction program for this plant.
These three policies are strictly followed during the field premises:
 QHSE Policy
 Seat Belt Policy
 Smoking Policy
ADMINISTRATION:
After QHSE we visited the Administration section where Sir Saboor Illahi Bugti briefed us about the job responsibilities of
Administration section, among which the major duties are Industrial Relations, arrangements of Boarding and lodging,
arrangement ofFlights, tolook after the house keeping accidents, securitypassesandcontracts dealing. Insummarized way
the dutyof administrationdepartment is the role of communicationbetweenthe localsand the upper management within
the plant. Inother words we can simplysaythat it acts like a CPU and directs the flow to the concerned departments.
PLANNING:
Planning is basically the allocation of time for the project and the resources required to successfully accomplish the project
in contrast with scheduling that further includes the allocation of team that is needed for that specific project.
In PPL Plans are of basically two types;
 5 year Plan (That specifies the targets in the upcoming years and expected budget allocation)
 Annual plan(It’s a bit detailedplanfor the upcoming year andit specifies the plans withrespect to each month)
Forecasting is done by going through the previ ous history to see what changes has to be made.
OPERATIONS and MACHINERY
GAS TURBINE GENERATORS
The total load required to drive the compressors and utilities is 6.8MW. Hence to respond to this power requirement the
power generation system of SFGCSincludes 4 Gas Turbine drivengenerators C201 (A,B,C,D) of 3.2MW each. 3 turbinesare
in working and one is standby always. For starting GT around 60% speed is required hence a VSD (variable speed drive) is
used for initial rpm of turbine. VSD drives the turbine then a reduction gear box is installed which lowers the rpm as per
requirement of the generators. The gear box lubrication is done with3 pumps ofwhich one is standbyalways andthe lubeoil

5. (SUI GAS FIELD) INTERNSHIPREPORT
ADNAN HATIMNEK 4
is circulatedfromthe lube oil tanks. Alsocoolingis done of lube oil since we needtemp of 60Cor else its viscosityis affected.
In control room synchronizing is done to match with power with other generators during startup.
SUL COMPRESSION
SUL (sui upper limestone) compression system includes 3 motor driven compressors of 2MW each. 2 compressors are
working whereas one is standby always. Since SUL does not consist of any H2S hence it does not require any purification
process. SUL fromwell comes to compressionplants where it first enters inslug catchers andscrubbers where solidparticles
and moisture is removed then it is compressed and is send to DHP (dehydration plant) , further after DHP a part of it is
returned to SFGCS since it is used as a fuel to drive SML turbines and the remaining is distributed.
SML COMPRESSION
SML (Sui Main Limestone) consists of 7 Gas Turbine operated 2 stage compressors. Gas turbine uses SUL as fuel and is
connected to an induced gear box where rpm are increased and further compressors are driven. Centrifugal Compressors
are used and the turbines used are of Frame 3 (frame shows the capacity of turbines, the greater the frame number the
greater is its capacity), 6 combustion chambers are installed (3 on each side) before compressors so that its efficiency is
improved and losses are reduced. The turbines are started with the help of primary turbine to give required rpm.
Compressors drivingthe turbines are axialcompressors always. Material usedfor rotors are alloys to give them strength.
HRL COMPRESSION
HRL (HabibRahi Line)Compressionsystem consist of 2 gas engine driven compressors of whichone is standby. The engine
is of 8 cylinder and has a whole system of cooling with fintype tubes and induced draft fan. Also scrubbers and knockout
drums are installed before gas enters the compressors.
UTILITY
Its mainpurpose isto supplyplant air andnitrogen(inert gasnon-flammable andusedto pressurize). Nitrogenis compressed
by 3 stage compressors
MACHINERY
The machinery section in the SFGCS Station is responsible for the proper maintenance of all the machineries installed
throughout the plant. Sir Fawad helpedus a lot inlearning different dimensions of this department. Some examples of the
machineries are the generators, compressor turbines, hydraulic and lube oil pumps, fin fan coolers, compressors, motors
etc. Machinery is one of the major area of Mechanical Engineers. The maintenance schedule of the different machineries
and their auxiliaries is classified into three main types:
 Breakdown Maintenance
 Preventive or Scheduled Maintenance
 Predictive or Conditioned Maintenance
After 10000hrs lining of combustion chamber is checked
After 20000hrs whole burning path is checked
After 40000hrs major overhauling is done
Work in progress during visit;
Overhauling and inspection of SML Alpha combustion chamber.
Setting of axial float of Alpha Turbine.
Fixing of agitator as it was producing sound due to worn out bearing.
Gear box fixing which drives induced draft cooling fans.
Other Learning during time period in Machinery
 Bearings and its applications
 Model of compressors and their types
 Wet and dry sealing systems of compressors
 Combustions chamber designs
 Vibrations concepts and parameters
 Engines used in HRL and different pumps
Compression Operation Explained: (Generalized)

6. (SUI GAS FIELD) INTERNSHIPREPORT
ADNAN HATIMNEK 5
 Slug Catcher:
The gas from the Wells first comes tothe Slugcatcher where condensate andother particles from the gas are being
separated.
 Inlet Scrubber:
There are 03 scrubbers for eachheader. Theyare horizontalcylinders withnumber of filters andbaffle p lates. The
Filters are designatedto remove the solidimpurities while the baffle plates removes any further condensates.
 Suction Knockout Drum:The function of all knockout drums is to remove any condensate and particles from the
gas.
 LP Compressor:
This compressor is responsible for increasing the gas pressure from 15/16 bars to 24/25 bars.
 LP Cooler:
The gas after compressor is at high pressure aswell as hightemperature soin order to reduce the temperature the
gas is then forced to move into the LP cooler that reduces its temperature.
 Intermediate Knockout Drum:
The gas then moves into the Intermediate Knockout drum to remove impurities.
 HP Compressor:
The gas then passes through the HP Compressor to increase the pressure to 60/65 bars.
 HP Cooler:
The gas then moves to the HP Cooler to reduce the temperature.
 Discharge Knockout Drum:
The gas before it is providedto the PurificationPlant andDHPpassedthroughthe last knockout drumto remove
any particles or condensate.
 Discharge Header:
The pressurized gas at a pressure of 65 bars then goes for further processes into the Purification Plant and DHP
through Discharge Header.
WORKSHOP:
The workshopinthe Compression Stationis designedto perform all the specific jobs that pops out duringthe maintenance
of anymachinery. The workshopis fullyfurnished and equippedwith allthe required machines to carryout productionjobs.
Machines in the Workshop:
 Shaping Machine
 Drilling machine
 Band saw Machine
 Wire brushing and buffing Machines
 Grinders
 Universal Milling Machine
 Lathe Machine
 Guillotine Machine
 Sheet Bending Machine
 Pipe Bending Machine
 Sheet Rolling Machine
 Liquid honing Machine
 Dry Blasting Machine
 Annealing Machine
 Computerized Balancing Machine
HVAC SYSTEMS:
Heating, Ventilation and Air Conditioning is very important in the design of medium to large industrial offices.
Ventilation in the HVAC is the process of changing or replacing air of any space to provide high indoor air quality which
involves temperature control, removal of moisturesand unpleasant odor. It also prevents the stagnation ofinterior air. The
HVAC system inthe SFGCS consists of 03 Chillers and04 AHU (Air Handling Units). The chillers usesR-22 Refrigerant witha
cooling capacity of 160 Ton.
CHILLERS:
 Circulating refrigerant enters the compressor in the saturated vapor state and is compressed to a high pressure
which ultimately rises the temperature as well.
 That refrigerant is nowinthe superheatedvapor state andpassed through condenser wher it is condensed bythe
surrounding air (rejects heat from the system).

7. (SUI GAS FIELD) INTERNSHIPREPORT
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 Now the refrigerant is in the saturated liquid state then passed through the expansion valve wh ere sudden
reduction in pressure causes the adiabatic flash resulting in the liquid and vapor refregerant mixture.
 The mixture of refrigerant isat lower temperature and goes throughthe shellandtube type heat exchanger where
the hot water from the AHU is present inthe tubes and gives off heat to the refrigerant andthen circulatesback
to the AHU. The Saturated vapor state of refrigerant then goeas back to the compressor.
AHU: (Air Handling Units)An air handler, or air handling unit (often abbreviated to AHU), is a device used to regulate and
circulate air as part of a heating, ventilating, and air-conditioning (HVAC) system.
Procedure:
 The Hot air from the buiding is suckedandpassedthrough a seriesof filters and the reaches a heat exchanger.
 In the Heat Exchanger cool water is flowing in the tubes that comes directly from the chillers.
 The water exchanges heat and reduces the temperature of air.
 The cooled and fresh air is then forced back into the building.
ELECTRICAL:
The SFGCS has its ownpower generation department andElectrical workshopthat is responsible for repairing the electrical
appliances.
Distribution: There were 09 substations that manages the distributionthroughout the plant. 01-05 Substation contains 02
transformers each and remaining06-09 contains 01 transformer each. All these 14 transformers are stepdown which gives
the output voltages of 2.4 KV and 400 V from the input of 6.6 KV for the High Tension (HT) and Low Tension (LT) lines
respectively.
PURIFICATION PLANT
Dated: (29th
may – 6th
June)
INTRODUCTION:
The Purification Plant of PPL Sui Gas Field is responsible for all the operations necessary to be carried out to supply the
Purified Gas to the SSGCL and SNGPL. The major infrastructure in Purification Plant consists of 08 Purification banks, 06
Dehydration Units, Water treatment plant, 10 Boilers, OldPower House andNew Power House. It is currentlypurifying 350
MMscfd of SML against the threshold of 900 MMscfd.
The PurificationPlant of Sui Gas Field wasestablished in 1952 and it is also consideredas one of the largest Gas Purification
Plant of Asia.
INSTRUMENTS:
In the instruments section Mr. Shahzadbriefedus about the major instruments that are controlledbythis sectionincludes
Control valves, Gages, Level meters etc. The control bench includes DCS (Honeywell USA) and for boilers they are using
Programmable logic controller (PLC) by (LN Bradley USA).
The controllers may be of two types which includes the Power supply cards, Input/ Output cards and key controllers. The
programminglanguage that is usedinthese controllers is Ladder Logic that is based on the function block mnemonics.
Apart from control valves the alsouses Solenoidal valves andbypass valves. Inthe sales monitoringstation theycontrolsthe
Moisture analyzer and Gas Chromatograph.
In the workshopof the Instruments sectionSir Shahjee is the manIncharge there andhe gives briefexplanationabout the
Level Troll (Make: SPRIANO).
The certainamount of time for whicha specific condition is to be observedto actuate a valve is knownas Retention Time.
LEVEL TROLL:
The level transmitters are microprocessor basedinstruments that combines the analog signal advantages (4-20mA)together
with the flexibility of digital communication (Standard FSK) using HART or FIELDBUS protocol. They can be remotely
configured by a universal handheld terminal (HHT) or by PC with a dedicated Interface.
POWER HOUSE:
The electrical department lookafter the power generation anddistributionaroundthe plant andthe residential area of the
Sui Gas Field. The main machineries in Electrical Department includes;

8. (SUI GAS FIELD) INTERNSHIPREPORT
ADNAN HATIMNEK 7
 Induction Motors (around 130)
The biggest motor is used for compressing air whose capacity is 95 KW.
 Gas Turbine Generators (04)
Make: SOLAR and KAWASAKI
Capacity: ≅1MW each
Speed: 22000 rpm max.
Gas: Purified Methane
 Steam Turbine Generators (02)
Capacity: 880 KW and 440 KW
Speed: 7000 rpm
 UPS (02 pairs)
Capacity: 30 KVA
 Diesel Generators (05)
Capacity: 250 KW each
The plant load is approximately 300-500KW andthe Steam Turbine Generators are dedicatedto makeupthis loadandapart
from this, 100KW from Gas Turbines is also utilized for Plant. The Diesel Generators act as backup for Plant.
Among 04 Gas Turbinesthe 03 remains infunctioning andprovides electricityto the residentialarea, messing andhospital
while the remaining 01 acts as a backup.
WATER TREATMENT:
Water treatment is important because the water suppliedto the boiler shouldbe demineralizedor non-conductive or else it
would produce scales and would damage boiler. Similarly soft water is used for cooling purpose.
Hence these above outputs are performed by 2 major processes
 Reverse osmosis
 Ion exchange which demineralizes water
OPERATIONS:
The operationsection of purification plant is responsible for the controlling all the parameters inthe running banks andthe
Glycol units. The two major operations are done at Purification Plant.
 Gas Sweetening Process: (Removes 𝐻2 𝑆 and 𝐶𝑂2 by the aid of MEA)
 Gas Dehydration Process: (Removes moisture by the aid of TEG)
Apart from these processes the water treatment is also monitored by this department.
GAS SWEETENING PROCESS:
 Inlet Scrubber:The Sour Gas is first introducedinthe scrubber andwhere entraineddroplets or slugs ofliquidare
removed from the gas stream by impaction devices.
 MEA Contactor: The Sour Gas then enters the bottom of the Contactor (Tray Column) and the objective is to
provide intimate contact between the gas andthe amine solvent so that the 𝐻2 𝑆 and 𝐶𝑂2 molecules cantransfer
from the gas phase to the solvent liquid phase
 MEA Scrubber: The Sweet gas then enters the MEA Scrubber and the MEA particles are removedfrom it which are
then recycled.
 Flash Tank: The rich amine solution is sent from the Contactor to a flash tank to recover hydrocarbons. The
pressure is dropped as it enters the tank, allowing the lightest of the hydrocarbons to flash. The heavier
hydrocarbons remain as a liquid, but separate from the aqueous amine because of lighter density.

9. (SUI GAS FIELD) INTERNSHIPREPORT
ADNAN HATIMNEK 8
 Lean/Rich Heat Exchanger: The rich solvent is preheated before entering the stripper. Because the lean amine
exiting the reboiler must be cooled before entering the absorber.
 MEA Reactivator: The rich amine enters from top and counters the steam from reboiler that breaks the bonds
between MEA and acid gases and therefore absorbs these gases.
 Reflux Accumulator: The steam along withacid gases thengoes intothe condenser where steam is condensedand
the acid gases are allowedto pass to the reflux accumulator where anyparticles of leanamine are redirected to
the stripper and the acid gases are flared off.
GAS DEHYDRATION PROCESS:
 Glycol Absorber: The wet gas enter the bottom of absorber and the dry glycol is sprayed from top absorbing all
water contents from gas and exiting as wet glycol.
 Dry Gas/DryGlycol Heat Exchanger: The drygas is usedto lower the temperature ofthe Dryglycol before entering
the Abosrber.
 Flash Drum: The wet glycol then enters the flash tank where pressure is reduced and hydrocarbons vapors are
removed and liquid hydrocarbons are skimmed off.
 Dry/Wet Glycol Heat Exchanger: The wet glycol is preheatedbefore entering the stripper. Because the dryglycol
exiting the reboiler must be cooled before entering the absorber.
 Glycol Stripper: The wet glycol after passing throughheat exchanger thenenters fromthe top of the stripper where
glycol is thermallyregeneratedbythe aid of reboiler and exits as dryglycol fromthe bottom of stripper whichis
then used for the next cycle.
 Reflux Accumulator: The steam along with some glycol particles after passing throughcondenser thenenter into
the reflux accumulator where water vapors are allowedto escape and glycol particles reenters the stripper.
MAINTENANCE:
In the maintenance section I meet Sir Adeel. This section deals with the maintenance of the whole plant. This section is
further divided into two categories:
a) Rotary: Turbines, Fans, Gearboxes, Engines, Fire Engines, Pumps, Motors etc.
b) Stationary: Vessels, Tanks, Boilers, Heat Exchangers, Pipes etc.
In Maintenance department we were welcomedbyDeputyChiefEngineer Mr. Yousuf whodida detaileddiscussiononmajor
machineryequipment suchas Fans, Pumps, Compressors, Blowers. Also he explainedus the structure of cooling towers with
the placement of gears, motors andbearings ininducedfan. Details of different type of pumps were discussed(centrifugal,
rotary, reciprocating of plunger type). Components such as bearings and couplings were discussed. Also turbines were
discussed. From stationary side he discussed boilers and heat exchangers in detail and the importance of valves and
governers.
STATIONARY: on going actvities
Boiler Maintenance Project: (Contractors AEPL)

10. (SUI GAS FIELD) INTERNSHIPREPORT
ADNAN HATIMNEK 9
The complete overhauling of Boiler 09 is inprogress. There are two types of Boilers installedinthe PPL whichincludes the
Forced draught type (forcedthe outer air to flowinside ofthe boiler) andInduceddraught type (Draw out the inner air). The
feed water is highlytreatedandmust be free from allcorrosive acids andminerals that causesscalingnormallyDemineralized
water is used. The feedwater is alsopassedfrom the DE aerator to remove anyair present i nthe water. The feedwater and
the steam pressure is maintained at 450 psi.
Overhauling of Heat Exchangers:
There were shell andtube type heat exchangers installed bothsingle anddouble pass. There were two cooling towers both
consists ofa fan, a turbine anda gear box. The secondarycoolingtower consists of a large building withfins mounted onall
the walls andthe hot water is forced fromthe topto pass throughthat fins, the fan sucks the surroundingair that extracts
the heat from the water in its waydown. Inthis waythe secondarycooling tower drops the temperature of the hot water
which is then recycled.
PRODUCTION FACILITIES
Dated: (7th
June – 11th
June)
INTRODUCTION:
The Productiondepartment is responsible for all the wells operations, well safetyand DHPunit, moreover the billingsection
also comes under this Department.
The Well Summary is as follows:
Total Drilled Abandoned Producing
SML Wells 52 05 46
SUL Wells 22 02 18
Dual Wells 17 01 16
PUB Wells 03 01 00
HRL Wells 02 00 02
Total 96 09 84
PRODUCTION CYCLE
WELL OPERATIONS:
After the securityclearance our convoywas allowedto leave the Sui Gas Fieldandwe visitedaround20 wellsandthe jobof
the crew of well operation is as follows:
 To ensure that all valves are in correct positions
 To record the readings of temperature, pressure and flow from the orifice graph.
 To check the oil level of hydraulic pump.
GAS WELLS SEPERATOR LIQUID
GAS
SML
SUL DHP
P.PLANT
SSGCL
SNGPL
𝐻2 𝑂
DISPOSAL TANK
CONDENSATE
Corrosion
Inhibitors
Well Safety
SFGCS

11. (SUI GAS FIELD) INTERNSHIPREPORT
ADNAN HATIMNEK 10
 To ensure the working of all gages.
 To ensure that the well fence is in correct condition.
 To report any unusual activity to the concerned personnel ASAP.
CATHODIC PROTECTION:
“It is the chemical or electrochemical reaction of a metal with its environment resulting in its progressive degradation or
destruction.”
In Sui Gas Field there are a lot of pipelines and around 84 wells thousands of feet deep and all are exposed to the
environment. Due to natural tendencyof metal to get back to its ore condition it is necessaryto employsome system that
prevents them from corrosion.
The tendency of every metal to get back to its ore condition can be defined as the Electrode Potential. So in Cathodic
ProtectionSystem the metal is made cathode of the electrochemicalcellandanexternal current is supplied negative enough
to prevent the electrons from escaping the surface of the metal and results in the elimination of the anodic area.
Two common practices of Cathodic Protection System are as follows:
a) Sacrificial Anode System: As the name suggests there is no current source but an anode with larger Electrode
potential then cathode (Well casing) to prevent the current flow.
b) Impressed Current Cathodic Protection System: In this system there is anexternalDCsource and Anodic Ground
Bed.
In Sui Gas Field the second one is installed on all wells with major components as follows;
 Power Sources: Thermoelectric Generators (TEG) by (Global Thermoelectric; Calgary, Canada) & ORMAT Energy
Converters (OEC) by(ORMAT;Texas, USA). Bothutilizes the heat energybyburning natural gas of the respective
well.
DRILLING AT WELL 95:
o Deep drilling operation carried out at well 95 in seek of a good pressure.
o It has beenestimatedthat if this deepdrillingproject gets successful anda highpressure is achievedthenthe field
could carry on with supply of gas for further 50 years.
o The depth aimed in this deep drilling operation is 3280m.
o Mud circulationsystem was briefed, its mainsignificance is hydrostatic pressure, coolingof the drillbit since due
to frictionit will heat upandlastlyto bring upcuttings.
o
SUL DEHYDRATION PLANT
o Consists of 2 units, eachhas capacity of 80mmcfd with inlet pressure supply from SFGCS of around 900psi

12. (SUI GAS FIELD) INTERNSHIPREPORT
ADNAN HATIMNEK 11
o Gas first enters upstream gas filters whichremoves anysolids or moisture, further it enters absorber where main
contact withglycol occurs. There are 9 bubble captrays inan absorber, gas gets incontact with glycol andglycol
absorbs all the moisture init. Further the gas enters downstream filters to remove glycol carryover andthen it is
supplied to SNGPL and SFGCS.
o Lean Glycol on the other hand enters surge tank then enters absorber, after absorber it goes to double acting
pumps andfollowed byflashseparator whichremoves anygas separator. Glycol thenenters a shellandtube type
heat exchanger and then glycol filters andfinallyinto fire type boiler where allthe moisture is removedinthe basis
of boiling point temperature difference.
WELL OPERATIONS VISIT:
o Christmas tree arrangement present on every head of the well includes;
Swab valve, Wing Valve , Subsurface safety valve and Master valve.
o Completion assembly.
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