[1]

TRAINING REPORT

ON

KALISINDH THERMAL POWER PROJECT

JHALAWAR-RAJASTHAN

Submitted to- Submitted by-

Dr. Ajay Jain Abhineet Kumar Singh

Mechanical Engineering Deptt. Roll No-1120370 (M-3)

N.I.T Kurukshetra

[2]

ACKNOWLEDGEMENT

I oblige to acknowledge my heartiest gratitude to all honorable people who helped me

during my summer training at KALISINDH THERMAL POWER PROJECT-

JHALAWAR,(RVUNL)RAJASTHAN.

I want to express my thanks to Mr. S. S. Meena Chief Engineer of KaTPP, S. P. Meena

(Training Co-ordinator) for granting me the permission for doing summer training at this

project and to give their valuable time and kind co-operation.

I am also thanks a lot to other staff members of RRVUNL, BGR & TCE for their further

co-operation to gain the better knowledge about the world class power plant project in Distt.–

Jhalawar, Rajasthan.

ABHINEET KUMAR SINGH

B. Tech 2nd Year

Mechanical Engineering

[3]

CONTENTS

1. INTRODUCATION

1.1. Contribution of Thermal Power Plant In India...................................... 04

1.2. INTRODUCATION OVERVIEW OF KaTPP………………………...05-07

1.3. ENERGY GENERATED IN KaTPP………………………………….. 08

1.4. PLANT OVERVIEW…………………………………………………… 08

1.5. PRINCIPLE OF OPERATION…………………………….................... 09

1.6. THERMAL PLANT OPERATION PROCEDURE………………….. 10-11

1.7. PULVERSIZED COAL FUELED POWER PLANT………………… 11-12

2. COAL HANDLING PLANT (CHP)

2.1. INTODUCATION………………………………………………………. 13

2.2. STAGES OF COAL HANDLING PLANT……………………………. 13-16

3. IMPORTANT PARTS OF THERMAL POWER PLANT

3.1. BOILER………………………………………………………………….. 17-18

3.2. TURBINE………………………………………………………………... 19-22

3.3. GENERATOR…………………………………………………………... 22-23

3.4. CONDENSER…………………………………………………………… 24

3.5. COOLING TOWER…………………………………………………….. 24-25

3.6. WATER TREATMENT PLANT………………………………………. 25

4. ESP AND AHP SYSTEM

4.1. ELECTROSTATIC PRECIPITATOR (ESP)…………………………. 26-29

4.2. ASH HANDLING PLANT (AHP)………………………………………. 29-30

5. CONTOLLING AND TRANSMISSION SYSTEM

5.1. CONTOL AND INSTRUMENTATION SYSTEM…………………… 31

5.2. SWITCHING AND TRANSMISSION…………………………………. 32-33

6. EFFICIENCY AND CONCLUSION

6.1. EFFICIENCY…………………………………………………………….. 33

6.2. CONCLUSION…………………………………………………………… 34

7. REFERENCE

REFRENCE………………………………………………………………. 35

[4]

1. INTRODUCATION

Everybody must be having a thought that a thermal power plant is a place where electricity is

produced. But do you know how it is produced? How the chemical energy stored in fuel is

converted into heat energy which forms the input of power plant i.e. steam and electrical energy

produced by generator? Power is the single most important necessity for common people and

industrial development of nation. In a conventional power plant the energy is first converted to a

mechanical work and then is converted to electrical energy .Thus the energy conversions

involved are:

The first energy conversion takes place in Boiler or Steam Generator, second in Turbine

and the last conversion takes place in the Generator.

A thermal power station is a power plant in which the prime mover is steam driven.

Water is heated, turns into steam and rotates the turbine which drives an electrical

generator after that steam pass through in a condenser where it condensed and recycled to

again in boiler; this whole cycle is known as RANKINE CYCLE.

[5]

1.1 CONTRIBUTATION OF THERMAL POWER PLANT IN INDIA

In India, Thermal Power Plant contribute about 60% of the total electricity produced.

Pie chart shows the electricity production percentage by different sectors-

Fig-percentage of electricity produced by different sectors

[6]

1.2 INTRODUCATION OVERVIEW OF KaTPP

Fig-KaTPP 3D VIEW

[7]

Kalisindh Thermal Power Project is about 760 K.M. from Kurukshetra Junction. It is

located in Jhalawar. The proposed capacity of coal based Thermal Power Project is 1200 MW.

The project site is about 12 km from Jhalawar (Distt.-Head quarter) and NH-12. Site is

comprising of 5 villages viz. Nimoda, Undal, Motipura, Singharia and Devri. It is 2km from state

highway No.19 and 8 km from Ramganj Mandi - Bhopal broad gauge rail line

Fig-route between Kurukshetra Junction to Kalisindh Thermal Power Plant

The site selection committee of Central Electricity Authority has visited the Nimodha and

its adjoining villages of Jhalawar Distt. And site was found techno- economical feasible for

setting up of a Power Project. The Govt. of Raj. have included that project in 11th five year plan.

The estimated revised cost of the project is Rs.7723 Crores. M/s. TCE Banglore has been

appointed as the technical consultant for the project. The state irrigation department has allotted

1200 mcft water for the project from proposed Kalisindh dam. The origin of the Kalisindh river

[8]

is from northern slop of Vindya Mountains . The river enters from MP to Rajasthan near village

Binda. After flowing 145 km in Rajasthan, the Kalisindh river merges in Chambal river near

Nanera village of Distt. Kota.Its catchment area is about 7944 sq.km in Jhalawar & Kota Distt.

The existing Dam is located at Bhawarasa village, primarily for P.H.E.D. purpose is being

uplifted for providing a storage of 1200mcft water for this power project.

The GOR has allotted 842 bigha Government land and acquired 1388 bigha private

khatedari land for the thermal project .Phase-1 will be constructed on 1400 bigha land only.EPC

contract has been awarded to M/s. BGR Energy System Chennai on dt.09/07/08,through ICB

route at cost Rs.4900Crores. Ministry of coal, Govt. of India has allotted Paras east and Kanta

basin coal blocks to RVUN in Chhattisgarh state. The RVUN has formed new company under

joined venture with M/s. Adani Enterprises for mining of coal blocks and new co mpany started

the work. Annual coal requirement for the project is 56 LacsTPA.GOR also decided to setup two

new units of2x660MW in next few years.

2x60 KALISINDH THERMAL POWERP ROJECT-JHALAWAR

OWNER RVUNL

OWNER’S TATA CONSULTING

CONSULTANT ENERGY LTD. MUMBAI

EPC BGR ENERGY SYSTEM LTD.

CONTRACTOR CHENNAI

[9]

1.3 ENERGY GENERATED IN KaTPP

Number of units=2

Electricity generated by one unit=600 MW

Total electricity negated by plant=2x600=1200 MW

1.4 PLANT OVERVIEW

Project Kalisindh Super Thermal Power Project Jhalawar

Capacity 1200MW(2x600 MW)

Project Site Village-Undel, Motipura, Nimoda, Singhania & Deveri of Tehsil

Jhalarapatan, Distt-Jhalawar

Project Location The project site is about 12 km from NH-12, 2km from state highway

and 8 km from proposed Ramganj Mandi-Bhopal broad gauge rail line.

Land Aera 2230 Bigha/564 Hq.(1400 bigha/350 Hq. in I stage)

Water Souce and

quantity

Dam on Kalisindh river and 3400CuM/Hrs.

Fuel Source Main Fuel-Coal from captive coal blocks(Paras east and kanta Basin in

Chhatisgarh state) Secondary Fuel-FO/HSD

Quantity of fuel(at

80% PLF)

Coal-56 Lacs TPA FO/HSD-13000-14000 KL/A

ElectroStatic

Precipator

99.9 % Capacity

Stack Height 275 Mtr

Estimated revised cost Rs.7723 Crores

[10]

1.5 PRINCIPLE OF OPERATION

For each process in a vapour power cycle, it is possible to assume a hypothetical or ideal

process which represents the basis intended operation and do not produce any extraneous effect

like heat loss.

1. For steam boiler, this would be a reversible constant pressure heating process of water

to form steam.

2. For turbine ,the ideal process would be a reversible adiabatic expansion of steam.

3. For condenser, it would be a reversible a constant pressure heat rejection as the steam

condenser till it becomes saturated liquid.

4. For pump, the ideal process would be the reversible adiabatic compression of liquid

ending at the initial pressure.

When all the above four cycles are combined, the cycle achieved is called RANKINE

CYCLE. Hence the working of a thermal power plant is based upon Rankine Cycle with some

modification.

[11]

1.6 THERMAL PLANT OPERATION PROCEDURE

The basic understanding of the modern thermal power station in terms of major systems

involved can be done under three basic heads viz. generating steam from coal, conversion of

thermal energy to mechanical power and generation & load dispatch of electric power.

COAL TO STEAM- The coal is burnt at the rate upto 200 tonnes per hour. From coal

stores, the fuel is carried on convey or belts to bunkers through coal tipper. It then falls in

to coal pulverizing mill, where it is grounded into powder as fine as flour. Air is drawn

into the boiler house by drought fan and passed through Preheaters. So me air is passed

directly to bunker and rest, through primary air fan, to pulverizing mill where it is mixed

with powdered coal. The mixture is then carried to bunker of furnace where it mixes with

rest of the air and burns to great heat. This heats circulating water and produces steam,

which passes to steam drum at very high pressure. The steam is then heated further in the

Superheater and fed to high pressure cylinder of steam turbine. . The spent steam is sent

to condenser, where it turns back to water called condensate. Condensate is sent tol ower

part of steam drum through feed heater and economizer. The flue gases leaving boiler are

used for heating purpose in feed heater, economizer, and air Preheater. The flue gases are

then passed to electro-static precipitator and then, through draught fan, to chimney.

STEAM TO MECHANICAL POWER- Steam first enters the high pressure cylinder of

turbine where it passes over a ring of stationary/fixed blades which acts as nozzle and

directs steam onto a ring of moving blades. Steam passes to the other cylinders through

reheater and the process is repeated again and again. This rotates the turbine shaft upto

3000rpm. At each stage, steam expands, pressure decreases and velocity increases.

MECHANICAL POWER TO ELECTRICAL POWER- To obtained the electrical

power from mechanical power we connect the shaft to an alternator’s armature. When the

armature is rotated and electric current is produced in the stator’s windings. The

generated electricity is of order 25,000 volts.

SWITCHING AND TRANSMISSION-The produced electricity is can’t to transmitted

as this state so It is passed to a series of three switches called an isolator, a circuit-

breaker, and another isolator. From circuit-breaker, current is taken to bus bars and then

to another circuit-breaker with it’s associated isolator before being fed to the main Grid.

Each generator has its own switching and transmission arrangement. Three-phase system

is used for power transmission.

CONTROL AND INSTRUMENTATION- Control and Instrumentation (C & I)

systems are provided to enable the power station to be operated in a safe and efficient

manner while responding to the demands of the national grid system. These demands

have to be met without violating the safety or operational constraints of the plants. For

example, metallurgical limitations are important as they set limits on the maximum

permissible boiler metal temperature and the chemical constituents of the Feed water.

The control and Instrumentation system provides the means of the manual and automatic

[12]

control of plant operating conditions to maintain an adequate margin from the safety and

operational constraints. Monitor these margins and the plant conditions, and provide

immediate indications and permanent records. Draw the attention of the operator by an

alarm system to any unacceptable reduction in the margins. S hut down the plant if the

operating constraints are violated.

1.7 PULVERIZED COAL FUELED POWER PLANT

A typical pulverized coal fueled power plant is based on Rankine Thermodynamic cycle.

“A Rankine cycle is a vapour cycle Furnace that relies on the isentropic expansion of high

pressure gas to produce work”.Let us see a super heat Rankine cycle:

This facility first produces steam in a boiler (steam generator). This steam is used to rotate

turbine which is connected to a shaft of generator. Hence electricity is produced here. The used

steam is then condensed in a condenser, and the condensed liquid is used again in the steam

generator. This is a simple phenomenon, understood by everybody. For all this we need a fuel.

As the name suggest here coal is used as fuel. Coal is one of the cheapest and most preferred

fossil fuel used as a key to most of the power plants. Usually delivered by train from Mines to

the Coal Handing Plant (CHP). The CHP unloads this it become more economical to unload the

coal. Then the coal stacked, reclaimed, crushed, and conveyed it to the storage silos near the

steam generator. Then it is fed through the Feeder to the Pulverizer. Feeder is mainly used to

weight the amount of coal going to the Pulverizer per hour. From the Feeder the coal is fed to the

Pulverizer which powders it and then it is carried to the steam generator using pressurized air.

Within the steam generator the coal is atomized and burned and the heat energy produced is used

for producing steam. Here two types of steam namely superheated & reheated steam are

[13]

produced in a cycle. The steam turbine generator converts the thermal energy of superheated and

reheated steam to electrical energy. The first energy conversion is carried in Boiler or steam

generator; the second is carried out in Turbine and the last one carried out in the Generator.

Initially the superheated steam is fed to High Pressure (HP) turbine. It has a temperature of

540° C (approx.) and a pressure of about 140 Kg/cm2. Then the exhausted steam from it is taken

to the reheater so that it can be reheated and fed back to Intermediate Pressure (IP) turbine. Here

the temperature is maintained the same as that of superheated steam but pressure is reduced to 35

Kg/cm2. Then the exhausted steam is directly fed to Low Pressure(LP) turbine having the

reduced temperature and pressure of about 1Kg/cm2. Then the exhausted steam from the LP

section is condensed in the condenser. The condensed liquid is moved from condenser by

Condensate Pumps through Low Pressure Regenerative Feed water heaters to a Deaerator. Boiler

Feed Pumps (BFPs) moves the deaerated liquid through HP heaters to the steam generators.

Extraction steam is supplied to the LP & HP regenerative heaters to improve cycle efficiency.

Then comes to the system of fans which keeps the system working by providing the valuable air

where required. There arethree pairsoffans, namely , ForcedDraft (FD)fan, Induced Draft (ID)

fan, Primary Air (PA) fan. FD fans supplies combustion air to the steam generator and PA fans

transports the coal into the steam generator. ID fans remove the flue gases from the steam

generator and exhaust it through chimney. Cooling water for the condenser is supplied by the

circulating water system, which takes the heat removed from the condenser and rejects it to the

cooling towers or other heat sink. This all working is controlled from a single place called

control room. It enables the operator to direct the plant operation for reliable and efficient

production of electrical energy. This is achieved by the control system installed by the C & I

group. These are DAS (Data Acquisition System), ACS (Analog Control System), FSSS

(Furnace Safeguard Supervisory System), and other relays governing numerous activities. Last

but not the least is the switching and transmission methods used here. The generated power

cannot be transmitted as such. It is stepped up to 132 KVA or 400 KVA then passed through a

series of three switches an isolator, a circuit breaker and an isolator. Three phase system is used

for the power transmission.Each generator has its own switchyard and transmission arrangement.

[14]

2. COAL HANDLING PLANT(CHP)

2.1 INTRODUCTION

Every thermal power plant is based on steam produced on the expanse of heat

energy produced on combustion of fuel. Coal is categorized as follows depending upon fixed

carbon, volatile matter and moisture content:

Anthracite having 86% fixed carbon

Bituminous having 46 to 86% fixed carbon

Lignite having 30% fixed carbon and

Peat having 5 to 10% fixed carbon

Coal from mines is transported to CHP in railway wagons. It is unloaded in track hoppers.

Each project requires transportation of large quantity of coal mines to the power station site.

Each project is established near coal mine which meets the coal requirements for the span of its

entire operational life. For the purpose each plant has Merry Go-Round (MGR) rail

transportation system. The loading operation of the coal rake takes place while it is moving

under the silo at a present speed of 0.8 Km/hr. the loading time for each wagon is one minute.

For unloading of coal from the wagons an underground track hopper is provided at the power

station.

The term coal handling plant means to store and to handle the coal which is transported by

the train and convey to the bunkers with the help of belt conveyers. Through the bunkers coal is

transferred to the coal mill and drifted to the furnace. The coal handling plant includes wagon

tippler, conveyer belt, crusher house, stacker & reclaimer, bunkers & coal mill.

COAL SUPPLY IN KaTPP-Ministry of coal, Govt. of India has allotted Paras east and

Kanta basin coal blocks to RVUN in Chhattisgarh state.

2.2 STAGES OF COAL HANDLING PLANT

WAGON TIPPLER-The term Wagon Tippler contains two words WAGON &

TIPPLER .Wagon means the compartment of train which is just like a container which is

used to carry the coal from mines to generating stations & the word Tippler means a

machine, which is used to unload the wagon into the hopper. Hopper is just like a vessel

which is made of concrete & it is covered with a thick iron net on its top. Here big size

coal pieces are hammered by the labors to dispose it into the hopper.

[15]

Capacity 90 tonnes

Types of Tipplers 1.Weighing type,2.Non weighing type

Angle of Tip 30 ‘to35’

Wire Ropes 1.Hoisting Ropes, 2.Counter Weight Ropes

Drive unit Motor 37.3 KW

Operating Cycle 10 wagons/Hour on 1 wagon Tippler

Time consume for one cycle 6 minutes

FEEDER- It is used to control the supply of crushed coal to the mill depending upon

load condition.It is installed under wagon tippler and hopper.In KaTPP there are 4

unbalanced Motor Vibrating Feeder installed in unit 1st.

CHRUSHER/RING GRANULATOR-In ring granulator the material is fed in to the

crushing chamber and is crushed by the rind hammers with impact and rolling action

across the feed, with concentrated pressure.This cracks the coal producing a granulator

product with a minimum of fines upto 20 mm square.

Capacity 500 Tonnes/hr

Machine Weight 30 Tonnes(approx.)

Max Feed Rate 500 Tonnes/hr

Rotor Speed 720 r.p.m

Motor 550 H.P

Volts 606 Kv

Phase 3 Phase motor

CONVEYORS-Conveyor belt is used to sent the coal from coal storage yard and also

used to sent crushed coal from store to mill bunkers. The carrying capacity of conveyors

belt is 750 tonnes/hrs that are installed in KaTPP.

Conveyor belt used in coal handling plant(CHP) are of 2 types

1. 5 ply x1000 mm width with 5 mm rubber top side and 5 mm rubber bottom side.

Total thickness of belt:-17 to 18 mm

[16]

Power:-1000KN/m2

2. 4 Ply x1000 mm width with 5mm rubber top side and 5 mm rubber bottom side.

Total thickness of belt:-17mm

Power:-800KN/m2

Cold joint are used in joining the conveyor, conveyor belts run with the help of electric

motor , gear box, fluid coupling geared coupling are installed at head of all conveyors.

PARTS OF CONVEYORS:

1) Flap Gate-it provide under coal transfer chutes for replacements of

crusher/conveyors.

2) Deflector Plate-Deflector plates are installed in the chutes coming on conveyors to

keep the coal direction in the centre of the conveyors.

3) Skirt board and Skirt rubber-These are provided on tail end chutes to avoid

spillages of coal from Conveyors.

4) Stone picker-Stone picker pick the stones from the running belt manually.

5) Metal Detactor-Electromagnets are provide on conveyors to avoid and to save

crusher parts and entry of iron pieces in crusher. It also stop the entry of iron pieces in

coal bunker to save damage of coal mills.

6) Guide Idlers-These idlers help to train/guide the conveyors.

7) Return Idlers-These idlers carries the conveyors belts in return side.

8) R.T.I (Return Training Idler)-These idlers are provided on return side to guide the

conveyors.

9) Impact Idler-These Rubber idlers are provided under chutes through which coal falls

on conveyors.

10) Carrying Idlers-These are installed to run the conveyor.

BUNKERS-Bunckers are fabricated to store the coal before sending to coal mills. Coal is

fed in the bunkers with the help of tripper trolleys installed at 37 m height for unit 1st and

2nd.These are 20 bunkers for unit 1st and 2nd.

Capacity of a bunker=500 tonne/bunker.

[17]

COAL BUNKERS-These are in process storage used for storing crushed coal from the

handling system. Generally these are made up of the welded steel plates with vibrating

arrangement of the outlet to avoid chocking of coal, normally there are six bunker supply

coal to the corresponding mills. These are located on the top of mills so as to add gravity

feeding of coal.

RECLAIM YARD-After filing the coal bunkers extra coal is taken to reclaim yard after

crushing of coal to storage.

COAL CIRCULATION-Coal is transported from the coal mine with the help of train.

Train wagons are emptied with the help of wagon tipplers and sent to the crusher for

crushing. From coal crusher it goes to the bunker through conveyor belt and from coal

bunker it move to R.C feeder feeds coal to the coal mill, where the coal is ground in to

powder from.

[18]

3. IMPORTANT PARTS OF THERMAL POWER PLANT

3.1 BOILER

Boiler can simply defined as the device where any liquid is boiled or Boiler may be

defined as a device that is used to transfer heat energy being produced by burning of fuel to

liquid, generally water, contended in it to cause its vaporization. Boiler, in simple terms, can be

called “Steam Generator”.

In simple way, boiler is a device used for producing steam. There are two types of boiler

(depending upon tube content):

a) Fire tube boiler

b) Water tube boiler

Here, boiler used is of water type. In the boiler, heat energy transfer takes place through tube

walls and drum. The gases lose their heat to water in the boiler or superheated. The escape heat is

used to heat the water through economizer.

ID and FD fans are used to produce artificial draught. The fuel oil is used to ignite the boiler and

pulverized coal is lifted from the coal mills by PA fans.

WATER TUBE BOILER USED IN KaTPP WITH 97M HIGHT

Various motors use in boiler are different rating and parameters 32KW ,15KW ,11KW ,&

3.3KW

Parameter in 15KW motor

Manufacturing CQ.GEAR BOX LTD.CHINA

Motor rating 15 KW

Speed 970 r.p.m

Rated voltage 416 V

Rated current 28.4 A

Impedance voltage 80.0 %

Oil weight 20 Kg

Core+winding weight 224 Kg

[19]

Total weight 600 Kg

Temp rise 50-55 deg cel.

BOILER AUXILIARIES-Efficiency of a system is of most concerned. Thus it is very

important to maintain a system as efficient as possible. So Boiler auxiliaries help in improving

boiler’s efficiency. Following are the important auxiliaries used

ECONOMISER: Its purpose is to preheat feed water before it is introduced into

boiler drum by recovering heat from flue gases leaving the furnace.

SUPER HEATER: It increase the temperature of steam to super heated region.

REHEATER: It is used for heat addition and increase the temperature of steam

coming from high pressure turbine to 540 deg. DRAFT FANS: They handle the supply of air and the pressure of furnace.

BOILER MOUNTINGS-These are used for the safe operation of boiler. Some example of

mountings used are water level indicator in drum, furnace temperature probe, reheat release

valve, pressure gauges indicating steam pressure etc.

[20]

3.2 TURBINE

Turbine is an m/c in which a shaft is rotated steadily by the impact of reaction of steam

of working substance upon blades of a wheel. It converts the potential energy or heat energy of

the working substance into mechanical energy. When working substance is steam it is called

‘Steam Turbine’

In the steam turbine the pressure of the steam is utilized to overcome external resistance

and the dynamic action of the steam is negligibly small.

PRINCIPLE-Working of the steam turbine depends wholly upon the dynamic action of

steam. The steam is caused to fall with pressure in a passage of nozzle, due to this fall in

pressure, a whole amount of heat energy is converted into mechanical energy & steam is

set moving with the reactor velocity. The rapidly moving particle of steam enter the

moving part of turbine and here suffers a change in the direction of mot ion which gives

rise to change of momentum and therefore to a force. This constitutes a driving force to a

turbine.

The passage of them/through the moving part of the turbine commonly called the blade,

may take place in such a manner that the pressure at the outlet sides of the blade is equal to that

of the inlet side. Such a turbine is broadly termed as outlet turbine or Impulse type.

On the other hand, the pressure of the steam at outlet from the moving blade may be less

than that at type inlet side of the blade. The drop of pressure suffered by the steam during its

flow through the moving blades causes a further generation of kinetic energy within the blades

and adds to the propelling force which is applied to the turbine rotor, such a turbine is broadly

termed as Reaction Turbine. Here in Kalisindh Thermal Power Project N600-

16.7/587/537,Re-Het,Three Casing,Four Exhaust, Tandem Compound Condenser Type Turbine

Used.

The turbine is of tandem compound design with separate High Pressure(HP),Indermediate

Pressure(IP) and Low Pressure(LP) cylinders.The HP turbine is of Single Flow type while IP and

LP turbines are of Double Flow type .The turbine is consdensing type with single reheat.It is

basically engineered on reaction principle with throttle governing.The stages are arranged in

HP,IP AND LP turbines driving alternating current full capacity turbo generator.

The readily designed HP,IP and LP turbines are combined and sized to required power

output,steam parameters and cycle configuration to give most economical turbine set.The design

and constructional feature have proved their reliability in service and ensure trouble free

operation over long operating periods and at the same time ensuring high thermal efficiencies.

[21]

[22]

TURBINE SPECIFICATION-

Rated output with extraction flow 600 MW

Speed 3000 r.p.m

Main steam throttle flow at HP Inlet 1848.5 TPH

Main steam pressure to HP turbine inlet 167 kg/sq.cm

Main steam temp. to HP turbine inlet 538 deg.cel

Re-heater steam flow at IP inlet 1587.942 TPH

Re-heater steam temp. at IP inlet 538 deg.cel

Steam pressure at LP inlet 35.12 kg/sq.cm

Steam flow at LP inlet 1353.7 TPH

Rotation Direction(view from turbine) anticlock wise

Number of stages 42

High pressure turbine-

a) Intermediate pressure

b) Low pressure turbine

c) Governing system

1 governing and 8 pressure

5 pressure stage

28 pressure stage

DEH(digital electro hydrolic)

Inlet steam flow governing type Nozzle+throttle

Rated exhaust pressure 0.09 kg/sq.cm

Type of bearing turbine 6 journal +1 thrust

Turbine allowable frequency 47.5 to 51.5 Hz

Turning gear rotation speed 1.5 r.p.m

Ist critical speed of HP & LP rotor 1722 r.p.m

Ist critical speed of LP-A rotor 1839 r.p.m

Ist critical speed of LP-b rotor 1903 r.p.m

[23]

Heat regenerative extraction system 3 HP heater +1 deaerator +4 LP

heater

Final feed water temperature 274.9 deg.cel

Maximum bearing vibration 0.076 m

Maximum allowable exhaust temp. 80 deg.cel.

Colling water design flow at condenser 70200 TPH

3.3 GENERATOR

Generator is the important part of thermal power plant.It is device which convert the

mechanical engery into electrical energy.Generator is driven by coupled steam turbine at a speed

of 3000 r.p.m.Due to rotation at high speed it get heat.So there is cooling construction enclosing

the winding core of the geretator.So that during the operation is being in normal temperature.

In KaTPP , Each of the 2 units have been provided with 3-phase turbo generator rated

output 706MVA, 18.525KA, 22KV, 0.85 lagging p.f., 984 rpm and 50 cycles/sec .The generator

has closed loop of hydrogen gas system for cooling of the stator and rotor at a pressure of

4.5kg/sq-cm(g).

[24]

GENERATOR SPECIFICATION FOR UNIT I AND II:-

Make CQ GEARBOX China

Type QFSN

Apparent output 706 MVA

Active output 600 MW

Power factor 0.85 lagging

Rated voltage 22 KV

Rated current 18525 Amp

Rated speed 3000 r.p.m

Frequency 50 Hz

Phase connections Double gen.star

Cooling mode H20-H2-H2

Rated H2 pressure 4.5 Kg/sq-cm

Terminal in generator 6

DIESEL GENERATOR SET

It is used to emergency porpuse to supply auxillary system of power plant.3 Set Diesel

generator are use in which one is standby. parameters of generator are as

Make BY STAMFOARD MAHARASTRA INDIA

Rating 1900 KVA

Speed 1500 R.P.M

Rated Current 2643.37 A

Rated Temp 40 Deg cel

AMPS 3.6 A

[25]

3.4 CONDENSER

In condenser, the water passes through various tubes and steam passes through a chamber

containing a large number of water tubes (about 20000).

The steam gets converted into water droplets, when steam comes in contact with water

tubes. The condensate is used again in boiler as it is dematerialized water and 5-6 heats the

water, which was in tubes, during the process of condensation. This water is sent to cooling

tower.

Condenser is installed below the LP exhaust. The condenser is of surface type made of

fabricated construction in single shell. The tube is of divided type double pass arrangement,

having two independent cooling water inlet, outlet and reverse and water boxes. This

arrangement facilitates the operation of one half of condenser when the other half is under

maintenance. The condenser is provided with integral air-cooling zone at the centre from where

air and non-condensable gases are continuously drawn out with the help of mechanical vacuum

pump.

Area of condenser = 9655 sq m

Cooling water flow rate = 2400 cubic m/Hr.

3.5 COOLING TOWER

It is a structure of height 202 m (tallest in the world) designed to cool the water(coming

from condenser) by natural draught. The cross sectional area is less at the centre just to create

low pressure so that ate air can lift up due to natural draught and can carry heat from spherical

drops. The upper portion is also diverging for increasing the efficiency of cooling tower. Hence

it is named as natural draught cooling tower.

In KaTPP two natural draught cooling towers (2 NDCT) is present with height 202 m each

for each unit.

[26]

Fig-Cooling Tower

3.6 WATER TREATMENT PLANT

As everyone know that the cost of any thermal power plant is cores of rupees. So major

problem of any thermal power plant is that how to prevent the corrosion. The water available

can’t be used in boilers as such. The objective of water treatment plant is to produce the boiler

feed water so that there shall be.

No scale formation ·

No corrosion ·

No priming or forming problems

Water used in thermal power plant is called ‘Dematerialized Water’ or DM Water.

[27]

4. ESP AND AHP SYSTEM

4.1 ELECTROSTATIC PRECIPITATOR (ESP)

Electrostatic Precipitator (ESP) is equipment, which utilizes an intense electric force to

separate the suspended particle from the gases. In India coal is widely used to generate power.

The exhaust gases are emitted directly into the atmosphere, it will cause great environmental

problems. So it is necessary to extract this dust and smoke before emitted the exhaust gases into

atmosphere. There are various methods of extracting dust but electrostatic precipitator is the

most widely used. It involves electric changing of suspended particle, collection of charge

particles and removal of charge particles from collecting electrode. Its various other advantages

are as follows:

It has high efficiency i.e. about 99%

Ability to treat large volume of gases at high temperature

Ability to cope with the corrosive atmosphere.

It offers low resistance to the flow of gases.

It requires less maintenance.

WORKING PRINCIPLE- The electrostatic precipitator utilizes electrostatic forces to separate

dust particles from the gases to be cleaned. The gas is passed through a chamber, which contains

steel plates (vertical) curtains. Theses steel curtains divide the chamber into number of parallel

paths. The framework is held in place by four insulators, which insulate it elect rically from all

parts , which are grounded. A high voltage direct current is connected between the framework

and the ground, thereby creating strong electric field between the wires in the framework

curtains.

Strong electric field develops near the surface of the wire creates Corona Discharge along

the wire. Thus ionized gas produces +ve and –ve ions. In the chamber plates are positively

charged whereas the wire is negatively charged. Positive ions are attracted towards the wire

whereas the negative ions are attracted towards the plates. On their way towards the curtains

negative ions strike the dust particle and make them negatively charged. Thus is collected on the

steel curtains.

The whole process is divided into the following parts:

Corona Generation

Particle Charging

Particle Collection

Particle Removal

Details of the following are given below-

[28]

Corona Generation- Corona is a gas discharge phenomenon associated with the

ionization of gas molecules by electron collision in regions of high electric field strength.

This process requires non-uniform electric field, which is obtained by the use of small

diameter wire as one electrode and a plate or cylinder as the other electrode. The corona

process is initiated by the presence of electron in strong electric field near the wire. In

this region of corona discharge, there are free electrons and positive ions . Both positive

and negative coronas are used in industrial gas cleaning.

In case of negative corona, positive ions generated are attracted towards the negative

electrode or wire electrons towards collecting plates. On impact of negative and serve as

principle means of charging dust.

Particle Charging- These are two physical mechanisms by which gas ions impact charge

to dust particles in the ESP. Particles in an electric fields causes localized distortion in an

electric filed so that electric field lines intersect with the particles of maximum voltage

gradient, which is along electric field lines. Thus ions will be intercepted by the dust

particles resulting in a net charge flow to the dust particles. The ions will be held to the

dust particles by an induced image charge force between the ion and dust particle and

become charged to a value sufficient to divert the electric field lines from particles such

that they do not intercept.

Particle Collection- The forces acting on the charged particles are Gravitational, Inertial,

Electrostatic and Aerodynamically. The flow of gas stream is turbulent flow because it

causes the particles to flow in random path through ESP. Particles will be collected at

boundary layers of collector pates. But if flow is laminar, charge will act on particles in

the direction of collecting electrode. This force is opposite to viscous drag force and thus

in the short time, particle would achieve Terminal (Migration) velocity at which

electrical; and viscous forces are equal. Thus the flow of the charged particle is decided

by the vector sum of these forces i.e. Turbulent.

Particle Removal- In dry removal of dust collected on plates, Rapping Mechanism is

used. It consider of a geared motor, Which moves along shaft paced near the support

collector electrode and is provided with cylindrical hammer. On rotating of shaft these

hammers strikes the supports causes plate to vibrates and dust is removed from plates.

Removed dust is collected in the Hoppers below the precipitator. At the time of starting

of precipitation of dust from flue gases, the hoppers are at normal temperature but the ash

collected is very hot. So there is a chance of ash deposit at the exit of the hopper thus

causing problem of removing the ash. To avoid this , heater are provide which increase

the temperature at the exit point o the hopper thus avoiding any undue accumulation of

ash at starting . In other method, the water is allowed to flow down the collector electrode

and hence dust is collected in hoppers below.

GENERAL DESCRIPTION-

The whole ESP is divided into two parts-

[29]

Mechanical System

Electrical System

Here we will discuss only Mechanical System (i.e. Precipitator Casing, Emitting and

Collecting System and Hopper).

Precipitator Casing-Precipitator Casing is made of 6mm mild steel plates with required

stiffness. The precipitator casing is all welded construction comprising of pre-fabricated

walls and proof-panels. The roof carries the precipitator internals, insulator housing,

transformer etc. Both emitting and collecting systems are hung from the top of the casing.

Emitting and Collecting System- Emitting System is the most important part of ESP.

Emitting system consists of rigid emitting frame suspended from four points on the top of

rigid emitting electrodes in the form of open spiral. The four suspension points are

supported on support insulators to give electrical insulation to the emitting frame. The

frame is designed to take up the retention forces of the emitting electrode. The emitting

electrode consists of hard drawn spiral wires and are fastened with hooks to the discharge

frame.

Collecting system mainly consists of collecting suspension frame, collection electrodes

and shock bars. Collecting electrode are made of 1.6 mm thick Mild Steel sheets formed

in ‘G’ Profile of 400mm width. Hook and guide are welded on one end and shock iron on

the dipped in rust preventive oil tank. Collecting electrodes bundles are properly bundled

in order to avoid any damage to electrode.

Hoppers- Hoppers are seized to hold the ash for 8-hour collection and is provided under

the casing of ESP. It is of Pyramidal Shape and is 56 in number. It is preferred to

evacuate the hoppers at the earliest as long storage of dust in hopper leads to clogging of

hopper. Also at the bottom of hopper electrical heating is provided to avoid any

condensation, which could also lead to clogging of hopper. Baffle plates are provided in

each hopper to avoid gas leakage.

RAPPING MECAHISM FOR COLLECTING SYSTEM- During electrostatic precipitation a

fraction of dust will be collected on the discharge on the discharge electrodes and the coro na will

be suppressed as the dust layer grows. So rapping is done in order to remove this dust by

hammering the electrodes. As the shaft rotates the hammer tumbles on to the shock bar that

transmits the blow to the electrode. The whole rapping mechanism is mounted on a single shaft,

which is collection of ash on the collecting electrode.

[30]

Fig-Electrostatic Precipitation Unit

4.2 ASH HANDLING PLANT (AHP)

The ash produced on the combustion of coal is collected by ESP. This ash is now required to

disposed off. This purpose of ash disposal is solved by Ash Handling Plant (AHP). There are

basically two types of ash handling process undertaken by AHP.

Dry Ash System

Ash Slurry System

DRY ASH SYSTEM- Dry ash is required in cement factories as it can be directly added to

cement. Hence the dry ash collected in the ESP hopper is directly disposed to silos using

pressure pumps. The dry ash from these silos is transported to the required destination.

ASH SLURRY SYSTEM- Ash from boiler is transported to ash dump areas by means of

sluicing type hydraulic system which consists of two types of system-

Bottom Ash System

Ash Water System

[31]

BOTTOM ASH SYSTEM- In this system, the ash slag discharged from the furnace is collected

in water impounded scraper installed below bottom ash hopper. The ash collected is transported

to clinkers by chain conveyors. The clinker grinders churn ash which is then mixed with water to

form slurry.

ASH WATER SYSTEM-In this system, the ash collected in ESP hopper is passed to flushing

system. Here low pressure water is applied through nozzle directing tangentially to the section of

pipe to create turbulence and proper mixing of ash with water to form slurry. Slurry formed in

above processes is transported to ash slurry sump. Here extra water is added to slurry if required

and then is pumped to the dump area.

FLY ASH SYSTEM-Even though ESP is very efficient, there is still some ash, about 0.2%, left

in flue gases. It is disposed to the atmosphere along with flue gases through chimney.

[32]

5. CONTROLLING , SWITCHING AND TRANSMISSION

5.1 CONTROL AND INSTRUMENTATION SYSTEM

Control and Instrumentation (C & I) systems are provided to enable the power station to be

operated in a safe and efficient manner while responding to the demands of the national grid

system. These demands have to be met without violating the safety or operational constraints of

the plants. For example, metallurgical limitations are important as they set limits on the

maximum permissible boiler metal temperature and the chemical constituents of the Feed water.

The control and Instrumentation system provides the means of the manual and automatic control

of plant operating conditions to maintain an adequate margin from the safety and operational

constraints. Monitor these margins and the plant conditions, and provide immediate indications

and permanent records. Draw the attention of the operator by an alarm system to any

unacceptable reduction in the margins. Shut down the plant if the operating constraints are

violated.

[33]

5.2 SWITCHING AND TRANSMISSION

The electricity is usually produced in the stator winding of the large modern generators at

about 25,000 volts and is fed through terminal connections to one side of a generator transformer

that steps up the voltage 132000, 220000 or 400000 volts. From here conductors carry it to a

series of three switches comprising an isolator, a circuit breaker and another isolator.

The circuit breaker, which is a heavy-duty switch capable of operating in a fraction of a

second, is used to switch off the current flowing to the transmission lines. Once the current has

been interrupted the isolators can be opened. These isolate the circuit breaker from all outside

electrical sources.

From the circuit breaker the current is taken to the bus bars-conductors, which run the

length of the switching compound and then to another circuit breaker with its associated isolates

before feeding to the grid.

Three wires are used in a ‘three=phase’ system for large power transmission. The centre of

the power station is the control room. Here engineers monitor the output of electricity,

[34]

supervising and controlling the operation of the generation plant and high voltage switch gear

and directing power to the grid system as required.

6. EFFICIENCY AND CONCLUSION

6.1 EFFICIENCY

Efficiency is defined as the ratio of output to input. Efficiency of any thermal power plant

can be divided into four parts-

1) Cycle Efficiency

2) Boiler Efficiency

3) Generator Efficiency

4) Turbine Efficiency

Efficiency of thermal power plant is defined as in the term of overall efficiency

i.e. overall efficiency = cycle x boiler x generator x turbine efficiency

CYCLE EFFICIENCY- Cycle efficiency is defined as the ration of energy available for

conversion in work to the heat supplied to the boiler.

BOILER EFFICIENCY- Efficiency of boiler depends upon the following factors:

a) Dry flue gas loss: Increase by excess air in boiler.

b) Wet flue gas loss: Moisture in coal.

c) Moisture in combustion loss: Hydrogen loss.

GENERATOR EFFICIENCY- Efficiency of generator is about 98% also its efficiency

depends upon:

a) Copper and iron loss

b) Windage losses

TURBINE EFFICIENCY-It means the efficiency of steam turbine in converting the heat

energy made available in the cycle into actual mechanical work.

[35]

6.2 CONCLUSION

This is my first practical training in which I learned lot of things and seen lot of huge

machine like Turbine, Boiler, Generator, cooling tower and many other things.

The architecture of the power plant, the way various units are linked and the way working

of whole plant is controlled make the student realize that engineering is not just learning the

structure description and working of various machine but the great part is of planning proper and

management.

I think training has essential for any student. It has allowed an opportunity to get an

exposure of the practical implementation to theoretical fundamentals.

[36]

7.REFERENCE

www.rvunl.com

www.googleindia.com

Generation of electrical power By B. R. Gupta, S CHAND PUBLICATION

Steam and Gas Turbine By R. Yadav , CPH

Engineering Thermodynamics By P. K. Nag, TMH