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there main product & also most unique & best quality in India. It is the only plant to produce ATF
from condensate. It also generates power via gas turbines. Approx 67 MW of electric power is
generated. The plant generates a revenue of 18-19 crores/day = 1.3 lakh/hour
Production process flow:
• Gas Reception Terminal (GT) :- To receive gas & condensate & distribute it to the various
units
• Gas Sweetening Unit (GSU) :- Sweetens the gas i.e. removes excess H2S
• Gas Dehydration Unit (GDU) :- Removes water & other liquid components
• Dew Point Depression Unit (DPDU) :- Removes Liquid hydro-carbons for effective transport
• Sulphur Recovery Unit (SRU) :- Converts H2S to non-toxic components by removing sulphur
• Sour Condensate Processing Unit :- This unit is used to remove H2S from the condensate
• Condensate Fractionig Unit (CFU):- Seperates the components of the condensate according
to boiling points
• L.P.G Unit :- To get various gaseous products from LPG
• Kerosene Recovery Unit (KRU) :- This is where all the kerosene products like SKO, ATF, HSD
are produced
Technical Details:
Working & Outline:
• The gas comes from the field of Vassai (earlier Bassein ) which is located 80 km North- West
(NW) of Mumbai the well there is 30 km deep
• Here the gas comes via two lines there are two lines for different roots & different pressure
1. 36 inch diameter pipe -231 Km long
2. 42 inch diameter pipe -244 Km long
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• This gas goes to the gas terminal After this the procedure is as shown:
• There are 3 GSU units & similar no. of GDU & DPDU units
• LPG from CWU goes to the LPG storage tank these tanks are circular in shape because it has
minimum stress
• While as in figure the gas goes to the HBJ (Hazira Bijapur Jagdishpur) pipeline
• The Dispatch modes for the other products are road, rail wagon & pipe line.
Products and Its Quantities Produced: • LPG >3000 m3 /day
• Naptha >5000 m3 /day
• SKO/ATF >600 m3 /day
• ARN(Aeromatic Rich Naptha) > 16500 m3 /day
• Propane >200 m3 /day
• HSD/Diesel >60 m3 /day (this is not for sale it is for internal use only)
Control Unit: • There is a separate Control Unit for Gas & Condensate & for LPG/Naptha/ATF
• All the main valves can be controlled from these control centres
• The valves can be controlled centrally & localy
• Each movement & pressure change can be measured & kept under control by these valves
• The pressure, temperature, flow & other important readings can be observed on the screen
then the valves can be controlled automatically manually by the computer or physically on
the site spot itself.
• The reaction response is directly but the valves take time to close
• In case of emergency shut down the whole plant can be shut down in the time of 2.5 min
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GSPC Niko
Introduction: Hazira is a 50 sq. km. gas field located 35 kms south-west of Surat city, Gujarat. Two-third of this
field lies offshore in water depths of 20 meters. While taking over, the field was estimated with
reserves of 50 million m³ of gas with one well drilled by the national oil company. After taking over,
GSPC-Niko commenced production in July 1995 after workover of Hazira well #1. Thereafter, 5 on-
land wells were drilled, which upgraded the in-place reserves to more than 20 BCM. Since the
reserves extended up to shallow offshore, a unique 100 sq. m. Land Based Drilling Platform
(Ratnakar), the first of its kind in India, was constructed in water depth of 10 to 12 meters. The land
based drilling platform is connected to land by a 1.5 km long causeway, which facilitated movement
of land rigs, men and materials. Seventeen wells were drilled from the LBDP. Thereafter, to probe
further offshore, an offshore platform was constructed about 4 km away from coast in water depths
of 20 meters. Out of sixteen wells required to be drilled from the platform, 6 wells have been drilled
so far. At present, production from Hazira field is 4 MMSCMD which is likely to go up to 5.5
MMSCMD after drilling all wells from the platform. GSPC - NIKO has also finalised a plan to drill oil
well for offshore platform and produce oil at the rate of approximately 2000 BOPD.
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Production Process Flow & Details:
Drilling site[LBDP(land based drill points)]:
• Drilling site is where the gas is drilled out its an onshore drilling site
• The drilling site had 4 wells
Out of which 3 were straight wells &1 was a slanting well
• The wells are about 1200 meters deep
• After the well is drilled the casing is completed then a Well Head or A Christmas Tree as it is
called is put on the pipe A wellhead is as shown
• In this structure from the top
(1) pressure gauge: which records pressure in the well
(2) crown valve :which adjust the pressure
(3) 2 wing valves on either side
(4) Upper master valve : adverse control valve to control any anomaly in well pressures
(5) Lower master valve : First valve to control any anomaly in well pressure
(6) Then below & on the side of the structure there’s a casing valve & ahead that is casing
pressure gauge which helps to control pressure on the casing
• Near the production wing valve is the flow line where the oil or gas flows out of the well &
just before the flow line is an
ESD(Emergency ShutDown valve) which shuts down & ensures that there is no accident
caused if the pressure exceeds 40psi
{
• 1 well has dried out & for further exploration a rig has been placed there
• The derric of the rig is placed at1○ -3○ angle so that the pipes & the kelley do not
touch or hit it during the drilling process
• The pipe is attached with a makeup backup tongs to the Hook for drilling
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• There is also a blow out preventer(Bop)which if the pressure suddenly increases inside
the well it shutdownd the whole system
}
• After the oil & gas is removed from the wells it goesd to the KOD (Knock Out Dump) in which
the gas is separated from the very little amount of oil & water the other dumps are also
removed this is by their densities
� The KOD contains a SRV(Safety Release Valve)
Which helps in controlling the specific amount of pressure in the KOD
� The KOD also contains an ESDV which shuts down the system if pressure exceeds
maximum pressure
• From the KOD the gas goes to the Test Separator where it is further separated & the Test
Separator line in both heat is used to separate gas
• From this 2 pipes go to the main gas production unit
Gas & oil production unit:
• It is the production site from which the oil & gas is produced & distributed to GSPL to
distribute it for various purposes • The 2 lines each from the onshore wells & off shore well are brought to this site • In each of these onshore & off shore There are 2 lines
1. H.P Line : High Pressure Line primarily gas content
2. L.P Line : Low Pressure Line Primarily oil content
• They pass through the Cathodic valve after this there is an ESDV
• Then both gas & oil go to separate intake headers
Here some amount of extra gas is removed to maintain +ve pressure this gas is called Purge
Gas
� This gas is burnt to avoid air pollution this process is called Flare Flare is as shown
� Now from intake header the path of oil & gas are separated
1) Gas
� Then the gas flows to 2 headers
1. High Pressure Header(H.P header) [White one]
2. Low Pressure Header(L.P header) [Yellow one]
� Gas then goes to a gas separator (Noise level 88.3 dB)
� It is a 3 phase separator
� From there it flows to the 1st compressor where the gas is reduced to 10-20kg/m3
pressure
� Then it flows to the
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DPCU(Dew Point Control Unit):-It use propane for chilling so that moisture is removed &
glycol is injected to stop the moisture to form ice & clot the flow of gas
� As water particles are removed pressure decreases so gas is re-compressed in the 2nd
compressor
� Then it is supplied to the users or distributors
2) Oil
� From the intake header the gas flows to the Oil Header [Black one]
� This oil is stored in Oil Batteries this will separate some more gas this ensures that no
gas is carried into the separator
� Then it goes to the Oil High Pressure separator (H.P separator) which uses gas valve to
push the oil with pressure
� At the outlet of these separators there are also Mobile Test Separators (M.S.T) these are
used for PVT analysis & if some thing wrong (eg more water content) they can divert the
flow
� Then BSW (Bottom Settling Water) is carried out where oil is heated so that the water is
removed
� Then the Oil goes to the Production Tank
� Then to the Slope Tank where oil is skimmed out
� This oil goes back to the Production Tank
� From there it goes to the Shipping Tank from there it goes to the users
� Safety in this process is necessary .The safety measures are
1. There is a foam tank which contains a balloon filled with chemicals if pressure
increases the balloon expands releasing chemicals thus preventing fire
2. There is an Emergency Tank for emergency’s like riots strike etc. which stores the oil The tanks are as shown
� There is a control unit which monitors these activities via DCS(Distributer Control
System), Flow meter, Moisture meter
� There is also an Oil loading Plant used to load oil in tankers .It has 2 pressure Loadings
are used
1. FTHP->Flow Tubing Head Pressure
2. STHP->Shut Tubing Head Pressure
o Before that it goes to the Bullet Tank where it is stored
o The oil is then Pumped into the tankers ny Hanger Loading
o Here oil is brought to the Hanger loading area via a pump
o Water, pressure, mass analysis all are done before loading
o LRC meter are used for loading measurement it stops loading when the tanker is full
there is always a preset value which when reached the tanker is said to be full
o ESDV are fit at all points to shut down immediately if adverse pressure condition is
observed
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o Earthing is also done to prevent static charge due to some amount of gas inn the
pipes
� This oil & gas then goes to the users via different channels
� Before the gas goes there gas chromatography is done to get the actual calorific value of
the gas
• Besides this there is also an ETP-> Effluent Treatment Plant :- to treat the water that is
used in the plant it contain
o Fillent Treatment Plant :- treatment of water to maintain BOD, COD
o Tilt Plate Interceptor (T.P.I):- To remove oil species.
o Chemical Dosing via Pexol, Pac & Lime is done to maintain POD, COD
o Primary Settling Tank (P.S.T):- This is used to remove slug The figure of primary settling Tank is shown Below
Control Unit:
• There is a control unit which monitors these activities via DCS(Distributer Control System),
Flow meter, Moisture meter
• All this is controlled automatically or manually from the centre
• This can also be controlled locally by valves at the points
• All valves are centrally controlled & monitored
• In case of a leak then first that unit is shut down & not the whole part isolation of the unit
can also be done via these valves
• The reaction time of the valves depends on the conditions
• But normally a valve closes completely in 1.2 -1.3 minutes of signal given
• So in case of an emergency the plant can be closed down maximum in 15 minutes
Tank for storage(Slug
is formed here)
Sieve Present that
removes the
unwanted slug from
this region
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GSPL
About GSPL:
GSPL, a GSPC subsidiary, has taken a lead in developing energy transportation Infrastructure in
Gujarat and connecting major natural gas supply sources and demand markets. Gujarat State
Petronet Limited is first company in India to transport natural gas on open access basis and is a Pure
Natural Gas Transmission Company.
Gas Transmission Network:
GSPL, a GSPC Group company is a pioneer in developing energy transportation infrastructure and
connecting natural gas supply basins and LNG terminals to growing markets. GSPL is continuously
expanding its pipeline network in Gujarat to to reach the demand centres by laying gas pipeline
network. The company has developed requisite expertise and confidence with proven project
management competencies.
Open Access
GSPL is first Pipeline Company in India operating on open access basis and is a pure transmission
network.
The transmission network of the company envisages development of systematic and seamless
pipeline network across Gujarat connecting various suppliers and users. The suppliers of natural gas
include traders, producers and LNG terminals. The users comprise industries such as power,
fertilizer, steel, chemical plants and local distribution companies.
Highlights of Gas Grid Project
• 1420 kms of gas pipeline in operation from Hazira-Vadodara-Ahmedabad-Kalol-
Himmatnagar-Mehsana-Rajkot-Morbi-Anjar-Jamnagar.
• Transports more than 36 MMSCMD of gas currently.
• 450 kms of gas pipeline under execution.
• Advanced engineering practices that provide efficient Natural Gas Transportation
• GSPL gives 4 EOIs to PNGRB for extending its Natural Gas Transmission System
across the country Grid Length - 5675 Kms.
Working and Details:
Working:
• GSPL is a transporter of gas it takes gas from sender to receiver this is done at various
pressure according to the receiver & senders wishes of pressure
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One such gas grid is as shown
• Pipelines transferring gas at high pressure are called transmission lines
• There are 3 types of such lines depending on the user
1. Domestic pipeline: For domestic use; pressure of about 7kg/m3
2. Low pressure pipeline: For small industries; pressure 7 kg/m3 -15 kg/m3
3. High pressure pipelines: For heavy industries; pressure 15 kg/m3 or higher
• Unlike GAIL ,GSPL works on an
Open Carrier Principle:- It works as an open transfer from buyer to end user they do not
own the gas but transfer it only.
• The price of gas id about 10-20$/mm3
• The total price earned by GSPL is about ½% -1%
• They have a std. Design to allow upto 95 bar pressure
• While the grid usually carries 60 bar Pressure
• The 1st pipe line was from Mohra- Hazira for Nikko it was a 14km long & 36 inch wide
pipeline .It was Low pressure pipeline
• At every inlet & outlet points of gas Gas chromatography is done every 5 seconds.
• This ensures the quality of gas intake from each company & the quality of gas supplied
• On this billing is done
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The pipeline map is shown below
Loop Line: It used to increase efficiency its parallel to the main pipeline
Risks:
i. Over Run :- If company extracts more than the contract
ii. Under Run :- If company extracts less than the contract
iii. If under any condition like riots or strike to keep the additional gas inside the problem
iv. Gas leakage leading to fire
Prevention & Cure:
1. Taping of pressure & velocity is done at interval stations at every 15 to 20 km by SCADA
system
o In SCADA system fluctuations , low pressure jerks recorded show leakage
2. Fire does not occur inside the pipes because of lack of oxygen
3. In case of a leak first the customers are in formed
4. Then the leaked gas pipe is isolated by valves & the gas is allowed to flow out from the
sides
5. Gas is released in a stop start fashion
6. The reaction of the valves is maximum 30 seconds to the change at the control station.
The 36 & 42 inch valves take 30-34 seconds & normal small valves take 15 seconds
7. Carbon steel Pipes are used for less damage.
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GSPC Gas
Introduction: There can be no doubt that Natural Gas is the fuel of the 21st Century. As a progressive company,
Gujarat State Petroleum Corporation (GSPC) has always tried to identify new trends and prepare
itself for the future. We at GSPC Group are laying the groundwork and preparing ourselves for the
future.
The GSPC Group’s foray into Gas Distribution in a big way bears testimony to our core philosophy of
being ‘A Complete Energy Company’.
Role:
The role of GSPC Gas is envisioned to be complementary to Gujarat State Petronet Ltd. (GSPL). At
every location where the GSPL network ends, the GSPC Gas retail network starts. This has resulted in
a strong synergy in network management besides ensuring that Gas is adequately available to all
retail segments in Gujarat.
Segments:
GSPC Gas is catering to the Natural Gas requirements of all the retail segments, which comprise of
industrial, commercial, transportation and residential customers.
Working & Details:
• Natural gas is received directly from Hazira plant
• Sent out after compression from the plant at 230 – 240 bar pressure The general layout of the plant is shown below
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• On the left side there is an air compressor & its control unit where the gas is
compressed to about 20 – 21 bar
Its fig. is as shown
• From there the gas goes into the compressor via a suction line to the main condenser
• There are 2 compressors
1. Old compressor: Compressing capacity of 250 scm (0.73scm=
1kg)
2. New compressor: Compressing capacity of 1200scm
It use Dresser Rand (D.R)
• New compressor :- The new compressor is a 3 stage piston compressor the hydraulic
piston compresses one way & the piston returns back due to inertia the gas compressed is
taken to the next stage. After each stage of compression there is water cooling this is
because the gas expands slightly which makes it easy & better for compression. So the gas
goes from 1st stage compression to cooling then to 2nd stage & then to the 3rd stage from
that it goes to the cascade. Now in the compressor there is an oil dropper for proper oiling
of the piston this is regulated by the heat of the pistons. So no lubricant is wasted.
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This compressed gas is stored in the CNG STORING CASCADE
• There are 40 cylinders
• Each cylinder has capacity 75 kg
• There are SOV(Solenoid Operated Valve) which controls the flow of gas going outside the
cascade
• This gas goes to the Priority Panel where the gas is separated into three banks
1. low bank: from pressure 50-160 bar
2. mid bank: from pressure 160-180 bar
3. high bank: from pressure above 200 bar The fig is as shown
From left the banks are
Low bank, mid bank, high bank
• From priority panel it goes to the dispenser
• There are 4 dispensers
2 for trucks, 2 sides for cars, 2 sides for rickshaws
• Each dispenser has 2 main parts
a. hoarse :the pipe through which the gas flows
b. adapter: the part which is attached to the vehicle
• 78 bar pressure is required for the valve to open
When the adapter is inserted into the car it gives signal to the mother board the mother
board activates the banks from
pressure is up to the limit then there is an automatic switched off. This can also
controlled by the control centre
The image of a mother board is as shown below
• Inside each dispensor there is
Each dispenser has 2 main parts
the pipe through which the gas flows
the part which is attached to the vehicle
pressure is required for the valve to open
When the adapter is inserted into the car it gives signal to the mother board the mother
board activates the banks from Low bank, mid bank, high bank respectively. Once the
pressure is up to the limit then there is an automatic switched off. This can also
controlled by the control centre
The image of a mother board is as shown below
Inside each dispensor there is
39
When the adapter is inserted into the car it gives signal to the mother board the mother
respectively. Once the
pressure is up to the limit then there is an automatic switched off. This can also be
40
Low bank, mid bank, high bank
• In black cylinders at the bottom are the spring loaded assemblers
• PNG (Piped Natural Gas )is also distributed at slightly lower pressure to different houses