A

PROJECT REPORT ON

INDUSTRIAL TRAINING

AT

GUJARAT STATE FERTILIZERS & CHEMICALS LTD(PU)

P R E P A R E D B Y

KASHISH PRAJAPATI

N I R M A U N I V E R S I T Y

AHMEDABAD

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ACKNOWLEDGEMENT

“The facet of care can be expressed in thought and action.”

Success is not only the brain but in addition of your heart,soul and multiplication with your attitude and approach.

My training at GSFC(PU),BARODA justifies the above statement.No project is ever the outcome of a single individual’s talent.

So first & formost I am grateful to MR. N.K. SHAH (DGM PERSONNEL) MR. V.S. RATHOD(DGM SERVICES)For showing trust & confidence on me and allow me to enhance my knowledge and gave me the best industrial experience.

My heartiest gratitude to MR. Ashok Patel,MR. M.N Patel,MR. ZALA who shaped my efforts and give me right direction from the best of his knowledge and experience.

I am also very much thankful to MR. H.N. GURJAR(DGM MECHANICAL) and MR. N.M Vyas(DGM TRG & HRM) for allowing me to visit head office of GSFC and giving me exposure of Cogeneration plant and Workshop.

A special thanks to all those engineers,operators and technicians who boosted my talent and gave me the practical knowledge about machinaries and industrial life.

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CONTENTS

INTRODUCTION OF COMPANY

MECHANICAL COMPONENTS USED IN CHEMICAL & PETROCHEMICAL INDUSTRY

COGENERATION PLANT

INDUSTRIAL SAFETY

UTILITY PLANT

MANAGERIAL ROLE OF MECHANICAL ENGINEER IN INDUSTRY

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Introduction of company

GSFC is established in year of 1967 with the setting up of 6 plants with an initial investment of Rs. 40 crores.

At present it has four units:

1. Fertilizernagar(Baroda unit-head office)

2. Fibre unit at Kosamba

3. DAP unit at Sikka

4. Polymer unit at Nandesari

All this four units have arount 27 different plants with turnover of Rs. 5000 crores

Per annum.

Vision:-

Our vision is to efficiently produce an array of valuable, superior and reliable products that enrich lives of millions in farms, industries and homes. The

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Company envisions operating in synergy with its environment and seeks to be recognized as an enterprise that is for total customer satisfaction and creates credible long term value for its stakeholders. Integrity and transparency remains the corner-stones of Company's governance.

Mission:-

The Company seeks to enrich lives of;customers by providing goods and services that add value to farm enterprises, industries and homesstakeholders by continuously adding value by managing responsibly, sensibly and maintaining ethical standards of highest quality

employees by providing them a work environment that fosters growth, learning, achievement and a perfect work-life balance.

Mechanical Components used in Chemical & Petrochemical Industry

Pump:-

A pump is a device that moves fluids or sometimes slurries by mechanical action.

Function of pump in the industry:

1. It transfers the fluid from one place to another against the direction of gravitational force.

2. It carries out the fluid from the close vessel.

3. It transfers the fluid from low pressure area to high pressure area.

(A) Centrifugal Pump

A centrifugal pump is one of the simplest pieces of equipment in any processplant. Its purpose is to convert energy of a prime mover (a electric motor or turbine) first into velocity or kinetic energy and then into pressure energy of a fluid that is being pumped. The energy changes occur by virtue of two

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main parts of the pump, the impeller and the volute or diffuser. The impeller is the rotating part that converts driver energy into the kinetic energy. The volute or diffuser is the stationary part that converts the kinetic energy into pressure energy.

A centrifugal pump has two main components:

I. A rotating component comprised of an impeller and a shaft.II. A stationary component comprised of a casing, casing cover, and bearings housing,stuffing box.

1. ImpellerThe impeller is the main rotating part that provides the centrifugal acceleration tothe fluid.

Wear rings: Wear ring provides an easily and economically renewableleakage joint between the impeller and the casing. clearance becomestoo large the pump efficiency will be lowered causing heat andvibration problems. Most manufacturers require that you disassemblethe pump to check the wear ring clearance and replace the rings whenthis clearance doubles.

2. ShaftThe basic purpose of a centrifugal pump shaft is to transmit the torques encountered when starting and during operation while supporting the impellerand other rotating parts. It must do this job with a deflection less than theminimum clearance between the rotating and stationary parts.

Shaft Sleeve: Pump shafts are usually protected fromerosion, corrosion, and wear at the seal chambers, leakage joints,internal bearings, and in the waterways by renewable sleeves. Unlessotherwise specified, a shaft sleeve of wear, corrosion, and erosionresistantmaterial shall be provided to protect the shaft. The sleeveshall be sealed at one end. The shaft sleeve assembly shall extendbeyond the outer face of the seal gland plate. (Leakage between theshaft and the sleeve should not be confused with leakage through the

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mechanical seal).

Coupling: Couplings can compensate for axial growth of the shaft andtransmit torque to the impeller. Shaft couplings can be broadlyclassified into two groups: rigid and flexible. Rigid couplings are usedin applications where there is absolutely no possibility or room for anymisalignment. Flexible shaft couplings are more prone to selection,installation and maintenance errors.In GSFC in most of the centrifugal pumps spider coupling is used.

In most of the cases single stage cenrifugal pump is used in this industry.As per requirements in some cases multi stage centrifugal pump is also used having impeller more than two.

• For high pressure at the outlet impellers can be connected in the series.

• For higher flow output impellers can be connected in parallel.Generally in all industry for cooling of mechanical seal fluid from discharge line is recovered.In GSFC handling of process condensate is difficult and harmful for environment because of its contents.This process condensate is used for cooling of mechanical seal that observes environment friendly and economical approach of industry.

(B) Non Seal pump

It is one type of centrifugal pump.In chemical industry where highly flammable and/or toxic fluid is circulated non seal pump which is also

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known as Canned motor pump is used because of its following salient features.

• Sealed leak proof structure integrating the pump and motor ensures environmental protection and on-site safety.Features includes low noise and vibration as well as high weather and dust resistance.

• As the fluid itself lubricating the sliding parts no lubrication is required.

• A highly reliable bearing monitoring device,E-Monitor,allows real time monitoring of the wear of bearings.

(C) Plunger Pumps

It is one type of reciprocaing positive displacement pump where the high-pressure seal is stationary and a smooth cylindrical plunger slides through the seal. This makes them different from piston pumps and allows them to be used at higher pressures. This type of pump is often used to transfer municipal and industrial sewage. Plunger pumps are reciprocating pumps that use a plunger to move media through a cylindrical chamber. The plunger is actuated by a steam powered, pneumatic, hydraulic, or electric drive.

Plunger pumps use a crank mechanism to create a reciprocating motion along an axis, which then builds pressure in a cylinder or working barrel to force gas or fluid through the pump. The pressure in the chamber actuates the valves at both the suction and discharge points. Plunger pumps are used

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in applications that could range from 70 to 2,070 bar (1,000 to 30,000 psi).The volume of the fluid discharged is equal to the area of the plunger multiplied by its stroke length. The overall capacity of the plunger pumps can be calculated with the area of the plunger, the stroke length, the number of pistons or plungers and the speed of the drive. The power needed from the drive is proportional to the pressure and capacity of the pump.

Seals are an integral part of and plunger pumps to separate the power fluid from the media that is being pumped. A stuffing box or packing is used to seal the joint between the vessel where the media is transferred and the plunger. A stuffing box may be composed of bushings, packing or seal rings, and a gland.

(D) Vacuum Pump

A vacuum pump is a device that removes gas molecules from a sealed volume in order to leave behind a partial vacuum. Electromechanical vacuum pumps trap air inside moving mechanical parts--like rotors--then force it through a pump device. This process creates a vacuum effect. These are motorized devices that require electricity to run.

Valve:-

There are following types of valve that are used in chemical industry.

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• Gate valve

• Globe valve

• Diaphragm valve

• Check valve

• Bellow seal valve

• Ball valve

1. Gate valve

Fluid is flowing in straight line and fluid gets minimum resistance in this type of valve.Pressure loss is minimum.Opening and closing of the valve is done right angle to the direction of flow.It can’t regulate the flow or pressure of the fluid.Main function of the gate valve is to isolate the process.

2. Globe Valve

It is used in discharge or bypass line to control or throttle the process.Pressure drop is high.It can regulate the flow of the fluid.Its construction allows it to change the direction of flow.Opening and closing is done in opposite direcion to the pressure.It is used where valve is operated frequently.

3. Diaphragm valve

It is used in acid or corrosion affected line.Maintenance is less and proper sealing can be obtained.But it is used for certain level of pressure and temperature only.

4. Bellow seal valve

A gate or globe valve that uses a cylindrical metal bellows to hermetically seal the valve against leakage.This valve is used where almost no leakage is necessary due to its hazardous chemical properties or its high cost.

5. Ball valve

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It is used where thick slurry or acid is passing through the line.Chocking problem is not there in this case.Thus back preesure doesn’t appear and leakage can be reduced.It is light in weight.

Compressor:-

(A) Reciprocating compressor

A reciprocating compressor or piston compressor is a positive-displacement compressor that uses pistons driven by a crankshaft to deliver gases at high pressure.

The intake gas enters the suction manifold, then flows into the compression cylinder where it gets compressed by a piston driven in a reciprocating motion via a crankshaft, and is then discharged.

• In this type of compressor for lubrication of each cylinder small motor is used to deliver the oil through veins.In this type of compressor high pressure and low discharge can be obtained.

• In Melamine and Amonia plant of GSFC two stage three cylindar double acting non lubricating reciprocating compressor is used to liquified amonia gas.Volume bottle is provided between two stages to provide the constant flow of gas to the compressor.

• In amonia storage tank plant rotary screw compressor is used. The gas compression process of a rotary screw is a continuous sweeping motion, so there is very little pulsation or surging of flow, as occurs with piston compressors.

(B) Centrifugal compressor

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Centrifugal compressor sometimes called a radial compressor achive a pressure rise by adding velocity(kinetic energy) to continuous flow of fluid through the rotor or impeller.This kinetic energy then converted into an increase in static pressure(potential energy) by slowing a flow through a diffuser.It is used wher low pressure with high discharge is required.Melamine plant of the company uses two stage lubricated centrifugal compressor of BHEL.They are provide axial thrust bearing to suppore high axial load.

Steam trap:-

Steam trap is a devise used to collect and automatically discharge the condensate water resulting from partial condensation of steam without allowing any steam to escape.The trap is so located that water from condensation of the steam in the steam pipe flows by gravity to it.The main types of steam traps are given below:

(A)Mechanical traps(float trap,bucket trap)

(B)Thermostatic or Expansion traps(metalic,liquid,balance pressure expansion traps)

(C)Relay traps(self contained,pilot,servo operated traps)

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If condensate is not drained immediately,it reduces operating efficiency by slowing the heat transfer process and cause physical damage through the phenmenon called as “water hammer”.

Centrifuge:-

A centrifuge is a piece of equipment, generally driven by an electric motor that puts an object in rotation around a fixed axis, applying a force perpendicular to the axis. where the centripetal acceleration causes denser substances to separate out along the radial direction (the bottom of the tube) and lighter objects will tend to move to the top.

In GSFC Ferrum make horizontal scraper centrifuge is used.It is solid-liquid seperation unit.In which melamine is filtered from melamine slurry and further dried upto 5% moisture.

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COGENERATION PLANT

Cogeneration, also known as “combined heat and power” (CHP), is the simultaneous production of heat (usually in the form of hot water and/or steam) and power, utilizing one primary fuel. It is one of the most common forms of energy recycling.

Conventional power plants emit the heat created as a by-product of electricity generation into the natural environment through cooling towers, flue gas, or by other means. In co generation system, the mechanical work is converted into electrical energy in an electric generator, and the discharged heat, which would otherwise be dispersed to the environment, is utilized in an industrial process in other ways.

The net result is an overall increase in the efficiency of fuel utilization.

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Cogeneration Efficiency,

η= Electrical energy generated +

Heat energy

generated

He

at Added

To Plant

It improves total system efficiency up to 85-90% as compared separate electricity generation at 30-35% efficiency and separate steam generation at 50 to 90% efficiency. This means that less fuel needs to be consumed to produce the same amount of useful energy.

This concept is highly beneficial to process industries which require both steam and power. For older plants, Co-generation is a cost-effective modernization. Cogeneration is the environmentally-friendly, economically-sensible way to produce power, simultaneously saving significant amounts of money and also dramatically reducing total greenhouse gas emission.

TYPES OF COGENERATION

1) On the basis of waste heat utilization : -

Waste Heat Utilization: - Main purpose is to generate electricity and hot water is released as by product.

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Total energy system: - The system is designed to supply both electric power and hear requirements of large building complex or community.

Combined purpose: - Here the objective is to produce both electricity and industrial process heat in form of steam, hot water, hot air, etc.

2) On the basis of cycles utilized : -

Topping Cycle

A topping cycle plant generates electricity or mechanical power first. There are four types of topping cycle cogeneration systems. The first type burns fuel in a gas turbine or diesel engine to produce electrical or mechanical power. The exhaust provides process heat, or goes to a heat recovery boiler to create steam to drive a secondary steam turbine. This is a combined-cycle topping system. The second type of system burns fuel (any type) to produce high-pressure steam that then passes through a steam turbine to produce power. The exhaust provides low-pressure process steam. This is a steam-turbine topping system. A third type burns a fuel such as natural gas, diesel, wood, gasified coal, or landfill gas. The hot water from the engine jacket cooling system flows to a heat recovery boiler, where it is converted to process steam and hot water for space heating. The fourth type is a gas-turbine topping system. A natural gas turbine drives a generator. The exhaust gas goes to a heat recovery boiler that makes process steam and process heat. A topping cycle cogeneration plant always uses some additional fuel, beyond what is needed for manufacturing, so there is an operating cost associated with the power production.

Bottoming Cycle

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Bottoming cycle plants are much less common than topping cycle plants. These plants exist in heavy industries such as glass or metals manufacturing where very high temperature furnaces are used. A waste heat recovery boiler recaptures waste heat from a manufacturing heating process. This waste heat is then used to produce steam that drives a steam turbine to produce electricity. Since fuel is burned first in the production process, no extra fuel is required to produce electricity.

ADVANTAGES OF CO GENERATION SYSTEM

1) It can adopt in general type of energy utilizing industries where both steam and power require.

2) There is no need of External Supply from GEB or Others By means There is No Power cuts, Trips, or Power Failure So Ultimately Reduce Production Loss

3) Same or highly efficient boilers can be used; No investment for infrastructure require.

4) Since power produced at the site of utilization at the premises of the industry, transmissions & distribution losses are negligible.

5) Processes in the plant require steam at different premises. This can be obtained by extraction backpressure or extraction condensing type turbine.

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6) Reliability of systems very high and it increases if it is operated in parallel operation with the grid; hence same system frequency is maintained.

7) Co generation plants require less land than the conventional thermal power plant.

8) The over all efficiency of co generation plant is about 80% to 90%. The power generated is also very cheap.

9) Island operation is possible if there is a grid failure hence especially in the process plant where production losses are huge co generation are blessings.

TURBINES

They are the basic elements of the power system, which utilize the high pressure and high temperature steam for their working. They produce mechanical rotation and hence are capable of driving other sources such as generators, alternators, etc. They can be broadly classified in two categories:

a. Steam Turbine:1) Impulse type2) Reaction type3) Impulse reaction type

b. Gas Turbine:They can also be classified upon their action such as back pressure type, condensing type, pressure compounded, velocity compounded, pressure

velocity compounded, Francis type, Kaplan type, Straight condensing type, Straight non condensing type, Auto extraction condensing type, Auto extraction non condensing type, Reheat type, Tandem compound regenerative type etc.

GENERATORS

They are the heart of the power system. They shall produce the electricity necessary in accordance to their KW rating. They are coupled to steam turbine or Gas Turbine or I.C engines in case of co-generation power plant. They can be electrically classified as follows:1. D.C Generators2. A.C Generators (Alternators)

COMBINED CYCLE POWER PLANTPHASE –III

INTRODUCTION

In a combined cycle power plant (CCPP), gas turbine-generator produces power. The heat in exhaust gasses of the gas turbine is received in a heat recovery steam generator. The steam so produced is utilized for driving a steam turbine which, in turn, drives an electric generator, thus producing additional power.

This is the most efficient method of generating power, compared to other methods such as conventional steam turbine based or IC engine based power plants.

In most combined cycle applications the gas turbine is the topping cycle and the steam turbine is the bottoming cycle. The major components that make up a combined cycle are the gas turbine, the HRSG and the steam turbine as shown in Figure.

Exhaust gas

Steam

Feed water

Steam turbine

Combustion chamber

Compressor

Fuel

Gas Turbine

Power

Generator

Heat recovery

Steam generator

Condenser

Condensate

Generator

BRAYTON CYCLEThe Brayton cycle is a thermodynamic cycle that describes the workings of the gas

turbine engine, basis of the jet engine and others. It is named after George Brayton

(1830–1892), the American engineer who developed it.

It consists of three components:

• A gas compressor • A burner (or combustion chamber) • An expansion turbine

Compressor

Combustion chamber

Gas Turbine

Exhaust gas

Fuel

Air from atmosphere

1

4

3

2Generator

⇒ IDEAL BRAYTON CYCLE:

• Isentropic process - Ambient air is drawn into the compressor, where it is pressurized.

• Isobaric process - The compressed air then runs through a combustion chamber, where fuel is burned, heating that air—a constant-pressure process, since the chamber is open to flow in and out.

• Isentropic process - The heated, pressurized air then gives up its energy, expanding through a turbine (or series of turbines). Some of the work extracted by the turbine is used to drive the compressor.

• Isobaric process - Heat Rejection (in the atmosphere).

⇒ ACTUAL BRAYTON CYCLE:

• Adiabatic process - Compression. • Isobaric process - Heat Addition. • Adiabatic process - Expansion. • Isobaric process - Heat Rejection.

1

2

3

4

T

S

1

2

3

4

P

V

Since neither the compression nor the expansion can be truly isentropic, losses through the compressor and the expander represent sources of inescapable working inefficiencies. In general, increasing the compression ratio is the most direct way to increase the overall power output of a Brayton system.

⇒ Methods to increase power: The power output of a Brayton engine can be improved in the following manners:

• Reheat, wherein the working fluid—in most cases air—expands through a series of turbines, then is passed through a second combustion chamber before expanding to ambient pressure through a final set of turbines. This has the advantage of increasing the power output possible for a given compression ratio without exceeding any metallurgical constraints (typically about 1000°C). The use of an afterburner for jet aircraft engines can also be referred to as reheat, it is a different process in that the reheated air is expanded through a thrust nozzle rather than a turbine. The metallurgical constraints are somewhat alleviated enabling much higher reheat temperatures (about 2000°C). The use of reheat is most often used to improve the specific power (per throughput of air) and is usually associated with a reduction in efficiency, this is most pronounced with the use of afterburners due to the extreme amounts of extra fuel used. ⇒ Methods to improve efficiency The efficiency of a Brayton engine can be improved in the following manners:

• Intercooling, wherein the working fluid passes through a first stage of compressors, then a cooler, then a second stage of compressors before entering the combustion chamber. While this requires an increase in the fuel

consumption of the combustion chamber, this allows for a reduction in the specific volume of the fluid entering the second stage of compressors, with an attendant decrease in the amount of work needed for the compression stage overall. There is also an increase in the maximum feasible pressure ratio due to reduced compressor discharge temperature for a given amount of compression, improving overall efficiency. • Regeneration, wherein the still-warm post-turbine fluid is passed through a heat exchanger to pre-heat the fluid just entering the combustion chamber. This directly offsets fuel consumption for the same operating conditions improving efficiency; it also results in less power lost as waste heat.

COG-III

Phase-III is a combine cycle power plant i.e. rankine cycle and brayton cycle power plant.

In a combined cycle power plant, NG is burnt in the gas turbine combustion chamber with the help of compressed air and the exhaust high temp flue gas after passing through the gas turbine producing power is passed to the heat recovery steam generator (HRSG).

In the HRSG high temp flue gases is used in producing steam at the rated capacity by the heat transfer across the boiler tubes. Thus it works on Bray ton cycle and modified Rankine cycle.

Flue gases having temperature 560°C which is going in to HRSG and it produce steam having capacity 75 TPH. There is also supplementary fuel firing system provided which is useful for when we need more steam than 75 TPH and increased up to 125 TPH.

The steam so produced is fed to the steam turbo generator (STG) to produce additional rated power. In case, STG is not be run, this steam at 37ata pressure is exported to process plants.

Thus, this cycle gives high thermal efficiency reduced cost of project installation per KWH produced rapid start and smooth operation of the plant. There is also counter flow type cooling tower having capacity 7500 m3/hr in phase-III.

30MW GAS TURBINE GENERATOR (GTG)

Gas Turbine machine is manufactured in General Electric co. America and supplied by M/S BHEL, Hyderabad and having the capacity of 30 MW at site conditions. It can be operated on NG/Naphtha/HSD or mixed fuel (NG and HSD/Naphtha) as fuel. HSD is used for the safe startup and shutdown of the machine during the liquid fuel firing.

⇒ STARTING SYSTEM

Before the gas turbine can be fired and started it must be rotated or cranked by accessory equipment. This is accomplished by a diesel engine operating through a torque converter to provide the power required by the turbine for startup. Starting system components include:

• The diesel engine • Torque converter with ratchet mechanism • Starting jaw clutch • Hydraulic ratchet self-sequencing control value assembly

In addition, there are several supplementary components required for sequencing and operation of the turbine starting system. During the starting sequence, the gas turbine is driven through the accessory gear by the diesel engine, torque converter, output gear, and the starting clutch. The starting clutch assembly and the engagement cylinders are mounted on the accessory gear assembly. The accessory gear is permanently coupled to the turbine compressor shaft by a flexible coupling. The accessory gear drives the main lube oil pump, and main hydraulic oil pump.

The diesel engine draws air from the accessory compartment through a filter into the turbocharger inlet. A diesel fuel tank is built in the turbine base. A high lift pump pumps the fuel from the base tank to the vented float tank. The main fuel pump draws fuel from the float tank through a filter into the injector headers. Each fuel injector draws the required amount of fuel form the headers, while the excess fuel (used to cool the injectors) is returned to the float tank. The diesel engine contains its own lube oil system. Cooling water is supplied to a diesel engine form the gas turbine cooling water system.

Torque converter assembly includes the torque converter, the hydraulic ratchet mechanism and an output gear unit. The torque converter transmits diesel engine output torque to the gas turbine accessory gear through a reversing gear. The torque converter is a constant input power device. The input power is only a function of input speed and does not vary with gas turbine speed. As the gas turbine reaches self sustaining speed, the stating clutch automatically opens and drops out. The diesel engine returns to idle speed for a five minute cool down period and is then shutdown.

⇒ AIR CIRCUIT

Atmospheric air is conditioned in the air-processing unit (APU).There are 384 self-cleaning type cartridge filters used for the filtration of air. Filter size is of 0.5-micron size.

Filtration is necessary to provide protection against the effect of the contaminated air that may degrade gas turbine performance and life through erosion, corrosion, fouling and plugging of cooling passages.The air is then compressed to 9 to 10 bar abs in 17-stage axial flow compressor. Air from the 5th stage is used for the sealing of turbine bearings

and air from the 11th stage is used to the surge control as it is bypassed to the GT exhaust plenum. Compressed air is mainly used in GT hot gas path cooling and APU filters cleaning.Airflow is controlled by the MARK-IV operated IGV vanes at the compressor inlet.

⇒ FUEL CIRCUIT

Natural gas supplied by GSPL or GAIL at 35 to 45 kg/cm² is conditioned in gas conditioning skid (GCS), after being reduced to 20 kg/cm²g through PCV. GCS consists of scrubber for removing dirt, oil traces and moisture particles. It also consists of filters for removing dirt particles. Conditioned NG is fed to the 10 combustion chambers after passing through the SRV (speed ratio valve) and GCV (gas control valve), which are operated by Speed tronic Mark-4 control system.

⇒ COMBUSTION SYSTEM AND FLUE GAS CIRCUIT

Compressed air and fuel is burned in the combustion chamber no 1 and 10. Flame sensors are provided to sense the flame. The hot flue gases are passed through three stages Gas turbine, where kinetic energy is converted into the mechanical energy thereby producing power. There is a load gearbox, which reduces the main shaft speed to the generator shaft speed to the ratio of 1:1.7.

The exhaust flue gases from the gas turbine is diverted to the bypass stack for simple open cycle operation or HRSG through the deviator damper at 560°C in combined cycle mode operation.

⇒ LUBRICATION AND HYDRAULIC SYSTEM

Lubrication Oil System is a closed loop, forced feed system containing Auxiliary Oil Pump (AOP), shaft driven main oil pump (MOP) and DC power driven EOP. The MOP or AOP pumps lubricating oil from the reservoir to the bearing. After lubricating the bearing, lubricant flows back through the

various drain lines to the Lube Oil reservoir. Pressure relief valve VPR 1 in the main pump discharge is provided to regulate the trip oil pressure and VPR 2 is provided to regulate to regulate BRG Header pressure.

High pressure Hydraulic oil pumped by shaft driven Main Hydraulic Pump (MHP) or motor driven auxiliary driven pump (AHP) is supplied to various servo valves of the control system i.e. inlet guide vanes servo valve, gas control servo valve and speed ratio valve.

⇒ COOLING WATER SYSTEM The cooling water system is designed to accommodate the heat-dissipation requirements of the turbine and generator lubrication system, the diesel cooling system and the turbine support. The cooling water system is comprised of the heat exchanger at the turbine aft support legs, the diesel engine heat exchanger, flow regulating valves orifices and hand valves.

The cooling water system circulates water as a cooling medium to cool several turbine generator components and to maintain the lube oil at acceptable lubrication system temperature levels. The water is circulated through water jackets surrounding the turbine support legs. A flow regulating valve is installed in the coolant inlet to the heat exchanger, which controls coolant flow to the heat exchanger.

⇒ COOLING AND SEALING AIR SYSTEM

The cooling and sealing air system provides the necessary air flow from the gas turbine compressor to other parts of the gas turbine rotor and stator to cool these parts during normal operation. When the gas turbine is operating, air is extracted from two stages of the axial flow compressor as well as from the compressor discharge. It is used to provide the following cooling and sealing functions:

• Seal the turbine bearings. • Cool the internal parts. • Cool the turbine outer shell and exhaust frame. • Compressor pulsation protection. • Provide pulse air to the self cleaning inlet air filter

Air extracted form the fifth stage and eleventh stage of the axial flow compressor and form the compressor discharge is used for sealing the bearings and internal turbine parts. It is also used to provide a clean air supply for air-operated control valves of other systems.

Cooling of the turbine shell and the exhaust frame is accomplished by two motor driven centrifugal blowers, which are mounted external to the turbine. The discharge of each passes to the turbine shell for cooling and flows into the exhaust frame via the exhaust frame strut passages.

HEAT RECOVERY STEAM GENERATOR

HRSG is manufactured in M/s BHEL, Trichy (Henry Vogt design). Boiler having capacity of 75TPH steam generation rate without supplementary fuel firing and 125 TPH with SF system with 355°C steam temp and 38kg/cm² steam pressure.

Flue gases from the gas turbine exhaust are used in combined cycle consideration for recovery of heat energy. This flue gases passes over the boiler super heater, evaporator, economizer and condensate pre heater (CPH) at various temperature and finally diverted to stack.

HRSG will have to recover the sensible heat of GTE to maximum extract possible for generation of max steam quantity so as to achieve highest co-generation/combine cycle efficiency.

GAS TURBINE GENERATOR

Gas turbine generator is connected to GSFC electrical system through 45MVA, 11/66 KV transformer (no 8) and the related circuit breaker. The generator is provided with brush less excitation system to prevent spark due to high hazardous conditions

INSTRUMENTATION AND CONTROLS

FOR PLANT

For safe, reliable and efficient operation of the plant most modern instrumentation such as SPPEDTRONIC MARK-IV control system, distributed control system, Bently Nevada turbo super visionary system, burner management system is provided.

INDUSTRIAL SAFETY

General safety can be classified into three categories:

1. Personal safety

2. Plant safety

3. Process safety

Personal safety:-

Human safety Human safety is one of the main concernsof any industrial sector.In order to safety of the employees various safety equipments have been madeavailable to them which are as follows:

• Safety helmet

• Safety shoes

• Gum shoes

• Hand gloves

• Ear muffs

• Air line Respiration system

• Breathing Apparatus Set

• PVC suit

• Full face shield

Plant safety:-

• All the pipes in the entire plant are coated with glass wool and thermocol for safety purpose.

• Micro sensor technology is used for leakage detection.

• Shower systems have been provided to reduce the effect of fluid come in contact with body by instant shower.

• Fire water supplies to fir hydrant with auto start pump at utility pump house.Altogether there are 72 fire hydrant points.Fire water pumps are alsooperated with diesel generator setin case of power failure.

• Filter water is supplied for cynide destruction & Ammonia absorption in atmosphere.

General Safety Rules:-

• Use appropriate electric torch instead of naked light at inflammable places.

• Never stand under suspended load.

• In case of gase leakage or fire always run in opposite direction to wind

• Do not tamper with any type of valves,electric switches or any other moving machinery installed in the factory area.

• Remove guard or clean machinery when in motion is prohibited.

.