CESC-TGS REPORT

PROJECT REPORT ON TITAGARH
GENERATING STATION
CESC LIMITED
AVISHEK GHOSH
JADAVPUR UNIVERSITY, KOLKATA
VACATIONAL TRAINING PROJECT REPORT
13/6/2016 – 25/6/2016 (2 WEEKS)
AT TITAGARH GENERATING STATION ,
B.T.ROAD ,KHARDAH ,NORTH 24-PARGANAS ,
WEST BENGAL ,PIN-700119 .

AVISHEK GHOSH 1
The Project report is not just mine. It is a collective effort of many people who helped me
a lot to successfully complete this project report and without the support of whom this
project report would not have been implemented. I thank Mr.Hirak Das (HRD) for
providing me with important data, description of the whole process and assisting us
throughout the training.
I would also thank Mr. Monotosh Chowdhury (Asst.Manager, HRD) of CESC LTD for
allowing me to have training under his careful supervision at TGS.
I am also grateful to Mr. Debdutta Maitra (GM, HR), Mr. D Basak (Station Manager), for
providing me with important data, description of the whole process and assisting us
throughout the training.
I am very grateful to Joydeb da for making me understand the operations and instruments
from the very grassroots level.
I would also thank all the employees of Instrumentation Maintenance Department for
explaining the operation details of the instruments at TGS.
Lastly I would like to thank the entire staff at TGS for their support. It has been a privilege
to have them by my side throughout the training period from 13.06.2016 to 25.06.2016.
Their tireless guidance, co-operation has led me to successful completion of this
vacational training.
DATE: 25th
JUNE, 2016 AVISHEK GHOSH
(3RD
YEAR MECHANICAL)
JADAVPUR UNIVERSITY
KOLKATA
ACKNOWLEDGEMENT

AVISHEK GHOSH 2
SL. No. TOPIC Pg. No.
1 ACKNOWLEDGEMENT 1
2 ABOUT CESC LIMITED 3
3 TITAGARH GENERATING STATION (TGS) 4
4 LOCATION OF A POWER PLANT 5
5 CYCLES OF A THERMAL POWER PLANT 7
6 ENERGY TRANSFORMATION IN STEAM POWER PLANT 10
7 THERMODYNAMIC CYCLES IN STEAM POWER PLANT 10
i) RANKING CYCLE 10
ii) REGENERATIVE RANKING CYCLE 12
8 DE-MINERALISED WATER PLANT 13
9 COAL HANDLING PLANT 16
10 BOILER 22
11 TURBINE 27
12 CONDENSER 28
13 ALTERNATOR 29
14 ELECTRO-STATIC PRECIPATOR 31
15 ASH REMOVAL SYSTEM 33
16 BASIC INSTUMENTS AT TGS 35
17 DISTRIBUTED CONTROL SYSTEM 37
18 CONCLUSION 39
CONTENTS

AVISHEK GHOSH 3
History and Generating capacity of different plants of CESE Limited.
STATS DATA
CESE LIMITED LICENSE AREA 567 Sq.Km
No OF CONSUMERS 2.9 Million
No OF EMPLOYEES 10000 (approx.)
GENERATION CAPACITY 1125 MW
SUBSTATION CAPACITY 7483 MW
POWER GENERATION IN YEAR 2010-2011 8756 MU
Few stats about CESE Limited.
Generating Station Year of starting Installed
capacity
Feature of
boiler
Titagarh (TGS) 1983 (4X60)MW Pulverized fuel
Southern (SGS) 1991 (2x67.5)MW Pulverized fuel
Budge Budge (BBGS) 1997 (3x250)MW Pulverized fuel
Calcutta has come a long way on the wings of power. CESC Ltd, a power utility
in India was set up in 1897. It was first Thermal Power Generation Co. in
India. In 1989 CESC became a part of RPG group which has a strong presence
in the fields of power generation, transmission network & distribution
network.
From its first DC station at Emambaugh Lane operating from April of 1899.
Units of CESC now became an ISO 9001: 2008 & 14001:2004 Company &
established. Its latest station at Budge Budge (1997) with a capacity of 750
MW which is one of the largest ever private industrial investments in West
Bengal.
ABOUT CESE LIMITED

AVISHEK GHOSH 4
TITAGARH GENERATING STATION (TGS)
TGS is one of the oldest generating station & is the first pulverized fuel thermal station of
CESC situated on B.T. road, Titagarh, West Bengal. It has total installed capacity of 240
MW (4x60). Its generating voltage is 10.5 KV. The plant started commercial generation
since 1983, when the first unit started operating. Subsequently the other three units
started in the years 1983, 1984 & 1985.
Plant Load Factor (P.L.F) of this plant is generally high (87.39) in 2006-07 & P.A.F. is 94.79
(2006-07). TGS is committed to ensuring required power supply to the CESC’s
distribution network in line with the varying level of electricity demand. In TGS the
generating voltage 10.5 KV is stepped up by generating transformer to 33KV. This 33 KV
supply is again stepped up to 132 KV in the receiving station & is sent to distribution
station & stepped down to 11KV.
Thereafter it is again stepped down to 6.6 KV, 415 V for distributing to consumers.
Operation & maintenance of the plant is part of the business activity of TGS. CESC
Central Turbine Maintenance department (CTM) is responsible for Turbo-Alternator sets
while, testing & calibration of protection metering equipments are done by company’s
test department. In 2006-2007 TGS captured the 5th position all over India due to its
great performance.
Currently TGS is used as a supporting unit to produce excess power during the time of
large demand (summer), and only one of the four boiler is functional and a power of
60MW is being produced. It does not have a re-heat cycle so is overall efficiency is also
low compared to ultra-modern power plants.

AVISHEK GHOSH 5
Location of a power plant is dependent on various factors as discussed below -
LOCATION OF A POWER PLANT
 Site Requirements: The size of the required depends on several factors like
the fuel used and its mode of delivery to the site, the area to be provided for
the fuel storage, cooling towers, switch yards, space needs for store yards,
workshops etc. The following factors are to be taken into consideration:
a) Station building b) Coal store and siding c) Cooling towers
d) Switch yard compound e) Surrounding area and approaches
 Water for Power Station: The water requirement for thermal stations
come under two main groups, the first requirement for steam generation and
second for cooling purpose. As far as the water for steam generation is
concerned, the problem is not of quantity but is quality. The requirement of
steam cycle is of the order of 3 to 4 ton/hr./MW. The amount of water
required for compensating is quite sufficient. In once through system of
circulating water the amount required will be approx. 20,000 m^3 / hr. /
100MW
 Coal for Power Station: The main areas where coal mines are located are
eastern region i.e. Bihar, Bengal, Central region, Singraull coal fields, Tamil-
nadu , Neyvell and small sources of coal are located in rest of the country as
well. The economic and efficient utilization of high ash content coals for
thermal power generation calls for special consideration. Firstly it is
economical to haul this coal over long distance because any transportation
means paying freight and handling charges on the useless ash; thereby
adversely affecting the cost of useful heat that can be recovered from the
coals.
 Transportation: In case of thermal power stations, the problem of transport
is to be considered mainly from the view point of fuel viz. coal economics and
for initial erection of the plant. Modes of transport are also to be considered
but may not be overriding factor in decision regarding feasibility. At this stage
the possibility of rail and road connections capable of taking heavy and over-
dimensioned loads of the machines are to be considered.

AVISHEK GHOSH 6
 Disposal of Effluents: The major effluents in case of thermal stations are in
ash and the flue gases. The disposal of chemically treated water generated in
the water treatment plant is also an effluent which requires attention for
disposal. The disposal of the gases and ash concerns mainly the atmosphere
and environment and that of water is concerned with the effect on marine life
of the rivers and canals. The methods of disposal of ash has been by
converting it into slurry and pumping the same by means of ash disposal
pumps of hydro aces to waste lands.
 Transmission: A route must be available for the transmission lines from the
site to the nearest grid system or major load point on the area board system
which can accept the station output. Increasing opposition from the public,
amenity societies and planners to Overhead lines makes the line increasingly
difficult to obtain and sometimes the only solution is to lay underground
sections of the line.
 Climatic Conditions: Climatic conditions of a place play a significant part in
the economics of capital investment. The tropical climate existing in most
parts of our country, calls for special attention to the ventilation and cooling
arrangements.
 Proximity to Airfields: Before the site is selected, its proximity to air fields
must be studied. The chimney height now goes up.
 Fishers and marine life: The intake of large volume of water from the river
and consequent throw off at a higher temperature after being treated with
chlorine will affect fishes. The effluent discharge from water treatment plant
has to be treated suitably before discharging it to the river.
 Personal requirement: The personal requirement will consist of persons
both in the skilled and unskilled labor categories. We may not find out any
difficulty in getting the skilled personnel required for different specialized jobs.

 Amenities: Some of the considerations kept in mind while locating a power
plant are also the availability of medical, education and related facilities. From
the point of view of the power plant, availability of ancillary industrial units
will also form one of the factors.


AVISHEK GHOSH 7
Any coal fired power generating station operates on the following four basic
cycles:
Pump
Boiler
Turbine
Condensor
CYCLES OF A THERMAL POWER PLANT
 Coal-Ash Cycle
 Air-Flue Gas Cycle
 Water-Steam Cycle
 Cooling Water Cycle
Coal-Ash Cycle: Raw coal is fed into the Fuel Handling Plant (FHP) or Coal
Handling Plant (CHP) after which it is sent to the coal bunker through the crusher.
Then through the coal feeder the coal is fed into the pulverizer where the coal
(20mm dia.) is pulverized. After that the pulverized coal is fed through the 24 (4 X
6) coal burners by primary air fans into the boiler furnace. After proper
combustion (determined by the 3-Ts: (temperature, time and turbulence) ash is
formed. This ash is of two types. The heavier variety is called the Bottom Ash while
the lighter variety passes out as flue gas into the Economizer. The bottom ash is
also obtained from the economizer. The bottom ash is obtained as clinkers which
are crushed into powder form by the scrapper-clinker grinder conveyer. Then the
bottom ash thus obtained is converted to slurry by water through the ash water
pumps. The flue gas from the furnace is fed to the economizer and the Air Pre-
Heaters (APH). From the electrostatic precipitator (ESP) the flue gas is vented out
into the atmosphere by the ID fans through the chimney. There is a government
guideline as to allow only 150mg/Nm3
suspended particles and TGS employs
opacity meter to allow only 35mg/Nm3
.
The ESP tries to collect all the suspended ash particles by high voltage discharge.
The ash thus obtained is the second variety of ash and is called fly ash. This fly ash,
as the bottom ash is converted into slurries. The slurry of both bottom ash and fly
ash together is collected in the ash slurry sump. The slurries from the sump is sent
to the ash pond employing three ash slurry pumps.

AVISHEK GHOSH 8
with it. The quantity of these matters
is small when oil is fired but it
becomes quite considerable when
coal is fired, particularly when high
ash content coal is fired. The ESP helps
in minimizing the dust concentration
of flue gas thus reducing the erosion
of ID FAN impellers, ducting and the
atmospheric pollution.
 Air-Flue Gas Cycle:
AIR CIRCUIT: The air requirement of the boiler is met by two forced draft fans (FD
FANS). The forced draft fans supply the necessary primary and secondary air.
About 80% of the total air (Secondary air) goes directly to the furnace wind box
and 20% of the air goes to the coal-mill via primary air fans (Primary air). The air
before it goes into the furnace or to the mill it is pre heated in the air pre heaters.
The air pre heater installed is a tubular type heat exchanger in which the heat
exchange takes place between flue gas and air. The flue gas flows through the
tubes and air flows over the tubes. The air heater serves to recovers the useful
heat in the outgoing flue gas (after recovery in the economizer) and thus improves
the efficiency of the boiler. At the air heater cold end the outgoing flue gas
contains constituents like sulphur dioxide. If the operating temperature goes
below the dew-point of the vapour then the vapour get condensed and react with
sulphur dioxide and sulphuric acid is formed which is corrosive in nature. The
possibility of cold and corrosion is more during lighting up of the boiler and at low
load. To avoid this corrosion problem the flue gas bearing the air is to be
maintained at a higher temperature. This is accomplished by bypassing the Air Pre-
heater during lighting up and low load condition when flue gas temperature is low.
The primary air is supplied to the five mills by the five primary air fans. The
primary air issued in the mill to dry the pulverized coal and to carry it into the
furnace. To ensure drying of coal a portion primary air is taken after passing
through the air pre-heater. A cold air line is also connected to the hot primary
airline before it enters into the mills. Temperature of the coal air mixture at the
mill outlet is controlled by admitting the cold and hot primary air proportionately.
FLUE GAS CIRCUIT: The flue gases move upward in the furnace and through the
rear gas pass in a downward direction to the air pre-heaters. The flue gas leaving
the air pre-heater pass through the electrostatic precipitators and then the
induced draft fan (ID FAN) sucks and forces the flue gas through the stack. The flue
gas which leaves the boiler furnace carries particles like ash, un-burnt carbon, etc.

AVISHEK GHOSH 9
 Water-Steam Cycle: Feed water is supplied to the boiler drum from economizer
outlet header through economizer links and these two links at the point of
entering the drum have been divided into 4 branch pipes. Altogether there are 8
down-comers from boiler drum, out of which two down-comer pipes termed as
‘short loop’ (water platen) divided into 4 branches before entering the boiler and
ultimately water flows to the drum through these 4 water platen outlet headers.
The front & the rear wall inlet headers feed the front and rear furnace wall tubes.
The furnace side walls are fed by two side wall inlet headers. The water in the
furnace sidewall, water wall platen and the extended side wall absorb heat from
the furnace. The resultant mixture of water and steam is collected in the outlet
headers and discharged into the steam drum through a series of riser tubes. Steam
generated in the front and the rear walls is supplied directly into the drum. In the
drum separation of water and steam takes place. The boiler water mixes with the
incoming water.
The steam is
superheated to the
designed temperature
and from the super-
heater outlet header
the steam is led to the
turbine via the main
steam-line.
 Cooling Water Cycle: There are NINE cooling tower fans each of voltage rating:
415 V. They are of ID fan type. All of them are controlled by MCC blocks.
Coo
ling
Tow
er
Condenser
Turbine
Steam
Steam
Condense Water
Discharge
Make-up
Water

AVISHEK GHOSH 10
RANKING CYCLE
The Thermodynamic Cycle generally in operation in any Steam Power Plant is Ranking Cycle
In modern Power plants Modified version of Ranking Cycle is used with Re-Heating.
Chemical Energy
stored in Fossil Fuel
Boiler
Heat Energy in
Super-Heated
Steam
Turbin
e
Mechanical Energy
in the Shaft of
Turbine
Altern
ator
Electrical Energy
in Generator
ENERGY TRANSFORMATION IN STEM POWER
PLANT
THERMODYNAMIC CYCLE IN STEM POWER
PLANT

AVISHEK GHOSH 11
The Processes involved are -
1-2 Isentropic compression in a pump 2-3 Constant pressure heat addition in a boiler
3-4 Isentropic expansion in a turbine 4-1 Constant pressure heat rejection in a condense
The Rankine cycle is a model that is used to predict the performance of steam engines. The
Rankine cycle is an idealized thermodynamic cycle of a heat engine that converts heat into
mechanical work. The heat is supplied externally to a closed loop, which usually uses water
as the working fluid. The Rankine cycle, in the form of steam engines, generates about 90%
of all electric power used throughout the world.
In an ideal Rankine cycle the pump and turbine would be isentropic, i.e., the pump and
turbine would generate no entropy and hence maximize the network output. Processes 1-2
and 3-4 would be represented by vertical lines on the T-S diagram and more closely
resemble that of the Carnot cycle. The Rankine cycle shown here prevents the vapour
ending up in the superheat region after the expansion in the turbine, which reduces the
energy removed by the condensers.
 Process 1-2: The working fluid is pumped from low to high pressure. As the fluid is a
liquid at this stage, the pump requires little input energy.
 Process 2-3: The high pressure liquid enters a boiler where it is heated at constant
pressure by an external heat source to become a dry saturated vapour. The input
energy required can be easily calculated using mollier diagram or h-s chart or
enthalpy-entropy chart also known as steam tables.
 Process 3-4: The dry saturated vapour expands through a turbine, generating power.
This decreases the temperature and pressure of the vapour, and some condensation
may occur. The output in this process can be easily calculated using the Enthalpy-
entropy chart or the steam tables.
 Process 4-1: The wet vapour then enters a condenser where it is condensed at a
constant pressure to become a saturated liquid.
Efficiency of Ranking Cycle –
𝜂 𝑡ℎ = Wnet /Qin = 1- (Qout/Qin)
Wnet = Qin – Qout = Wturb, out – Wpump,in

AVISHEK GHOSH 12
In TGS, REGENERATIVE RANKINE CYCLE is used.
Closed Feed Water Heater Regenerative Ranking Cycle
The regenerative Rankine cycle is so named because after emerging from the condenser
(possibly as a sub-cooled liquid) the working fluid is heated by steam tapped from the
hot portion of the cycle. On the diagram shown, the fluid at 2 is mixed with the fluid at
4 (both at the same pressure) to end up with the saturated liquid at 7. This is called
"direct contact heating". The Regenerative Rankine cycle (with minor variants) is
commonly used in real power stations.
Another variation is where bleed steam from between turbine stages is sent to feed
water heaters to preheat the water on its way from the condenser to the boiler. These
heaters do not mix the input steam and condensate, function as an ordinary tubular
heat exchanger, and are named "closed feed water heaters".
The regenerative features here effectively raise the nominal cycle heat input
temperature, by reducing the addition of heat from the boiler/fuel source at the
relatively low feed water temperatures that would exist without regenerative feed
water heating. This improves the efficiency of the cycle, as more of the heat flow into
the cycle occurs at higher temperature. This process ensures cycle economy.

AVISHEK GHOSH 13
The river water contains suspended matter with colloidal particles and some of organic and
inorganic impurities which make it necessary for chemical and mechanical treatment in WT
plant before being used as clarified and filtered water. The impurities in water are of two
kinds, volatile and non-volatile. Volatile impurities can be expelled from water to a very great
extent by it in fine streams or droplets into the atmosphere. By this means foul gases
dissolved in it are removed. By the Cascade Type, 5 Stage Aerator the iron dissolved in water
also is oxidised and thus precipitates, enabling easy
removal by filtration. The pH value of the water is
often increased due to aeration owing to the removal
of CO2 from it. Lime dosing is done to promote the
coagulation efficiency. It also helps to maintain the pH
value around 7.4 during coagulation.
The non-volatile impurities like clay, vegetable
matter, colouring matter and bacteria being minute
escape through filters. Hence alum is added to
sedimentation and hence, filtration. In the clari-
flocculator mechanical agitation is created and the
mixture is allowed to fall into a trough below for
integrate mixing with the chemicals used, creating violent turbulence. The flocculated water
is admitted into the clarifier tank from the bottom of the flocculator tank in a continuous
rotary upward movement that enhances the rate of deposition of sludge on the floor of the
tank. This sludge is removed by continuous sweeping through a desludging valve. The
clarified water is then collected in the gravity filter beds where they are filtered through a
layer of sand and gravel by the effect of gravity. Now to clean the pores in the filter bed,
DE-MINERALISED WATER PLANT

AVISHEK GHOSH 14
backwashing is done. This process of backwashing involves flushing by compressed air and
water from beneath the filter bed and simultaneous drainage of the turbid water. The
filtered water thus is collected in the filtered water sump from where through colony filter
pumps this water is supplied to the colony. Through plant filter pumps the clarified water is
supplied to the DM plant & the Bearing Cooling Water (BCW) sump or the non-dm plant.
Water is required for industrial process. From the Ganges the water is taken.The water is
first processed to deminarilize in DM plant. However natural water contains dissolved salts,
alkaline salts such as bicarbonates & carbonates of Ca, Na & Mg. there are also other
dissolved impurities such as sulphates, chlorides & nitrates of Ca, Mg & Na. Silica, dissolved
CO2 and metals like Fe, Mn & organic matters are also present. Ion exchange resins are
porous materials that contain inert base attached to which are free ions & can be free to
move about within the resin structure.
At first water is taken from Ganges is taken to main water bus and is sent to water chamber where alum is
mixed. By clarifoculator system and flushing of air the alum gets mixed properly in water and all the mud,
algae etc. settles down. Upper portion of the water which is collected in reservoir which is divided into
two sections. One portion goes for treatment & other is for cooling of machines, coal yard & other services.
There are three types of pump.
1. Clarified water pump 2. Drinking water pump 3. Service water pump
PROCESSES: The clarified water is fed to pressure sand filter (PSF). There are three PSF (A, B, C) & used
to remove sand, mud etc. From PSF the water is fed to the activated carbon filter (ACF). In the ACF it
absorbs any chlorine. There are 3 no’s of ACF (A, B, C) & used to remove the small particles & bacteria.
From AC the water is moved to Strong Acid Cation (SAC) which are three in no. (A, B, C). In SAC the cation
exchange resin causes removal of the cation & in their place hydrogen ions are released in the solutions.

AVISHEK GHOSH 15
REGENERATION: While supply of exchangeable ions within the resin is exhausted, the quality of
treated water from the resin deteriorates & the resin requires regeneration.
 SAC: RNa + HCl = RH + NaCl ; R2Mg + H2SO4 = 2RH + MgSO4
 SBA: RCl + NaOH = ROH + NaCl
 WBA: RHCl + NaOH = R + H2O
SPECIFICATION: In lower tower there are 9 IM PUMP used.
There are used three types of pumps:
1. Service water pump 2. Drinking water pump 3. Clarified water pump.
 There is Oil skinning station where removes oil from the water. 2 tanks are used. 1 tank is full& the other
tank is empty. A rotating device is attached on top & it rotates slowly along the tanks boundary.
Effluent re-circular system
De-Gassed Water Pumps MB Air Blasts
Pump3 1kg/cm2
Pump4 1kg/cm2
Pump1 5kg/cm2
PRESSURE
SANK
FILTER
(PSF)
ACTIVATE
D CARBON
FILTER
(ACF)
STRONG
ACID
CATAION
(SAC)
DE-
GASSED
WATER
TANK
WEAK
BASE
ANION
(WBA)
STRONG
BASE
ANAION
(SBA)
MIXED
BED
DM
WATER
TANK
CONDENS
ATE
STORAGE
TANK
(CST)
BOILER
SBA BASIN 3
WBA BASIN 3
PRESSURE 2kg/cm2
VOLTAGE 415 V
SPEED 2920 rpm
CURRENT 310 Amp
The no of PSF (pressure sand filter) vessel 2
The no of ACF (Activated charcoal filter) vessel 2{[A] ---2kg/cm2 ; [B]---2.4kg/cm2}
The no of SAC (SULPHURIC acidic cation) vessel 3{[A] ---off ; [B]--0.5kg/cm2 ; [C] ---2kg/cm2}
NOT RUNNING 2
MIXED BED 3
PRESSURE 6kg/cm2

AVISHEK GHOSH 16
In a coal based thermal power plant, the initial process in the power generation is “Coal
Handling”. So in this article i will discuss the overall processes carried out at a Coal Handling
plant in a coal based thermal power generating station. The huge amount of coal is usually
supplied through railways. A railway siding line is taken into the power station and the coal
is delivered in the storage yard. The coal is unloaded from the point of delivery by means of
wagon tippler. It is rack and pinion type. The coal is taken from the unloading site to dead
storage by belt conveyors. The belt deliver the coal to 0m level to the pent house and
further moves to transfer point 8.
The transfer points are used to transfer coal to the next belt. The belt elevates the coal to
breaker house. It consists of a rotary machine, which rotates the coal and separates the
light dust from it through the action of gravity and transfer this dust to reject bin house
through belt. The belt further elevates the coal to the transfer point 7 and it reaches the
crusher through belt. In the crusher a high-speed 3-phase induction motor is used to crush
the coal to a size of 50mm so as to be suitable for milling system. Coal rises from crusher
house and reaches the dead storage by passing through transfer point 8.
Schematic of CHP of TGS
COAL HANDLNG PLANT
CHP (Coal Handling Plant)
Conveyer at CHP

AVISHEK GHOSH 17
Raw Coal
(Grade 4-6 ,
Bituminous)
Wagon
Trippler Grid
(300mm-12'')
Crusser
(20mm-3/4")
Coal Mill
(75 Micron)
Furnace of
Boiler
 Pull Chord Switch: A series of such switches are arranged in series at a 1m
distance on the side of conveyor belt. The power supply to rotor of the conveyor
belt is established only if all switches in series are connected.
 Vibrating Feeder: The coal stored in a huge hub is collected on the belt through
vibrations created by the vibrating feeder.
 Flap Gates: These are used to channelize the route of coal through another belt
in case the former is broken or unhealthy. The flap gates open let the coal pass
and if closed stop its movement
 Magnetic separator: These are used to separate the ferrous impurities from
the coal.
 Metal Detector: These are detect the presence of any ferrous and non-ferrous
metal in the coal and send a signal to a relay which closes to seize the movement
of belt until the metal is removed. It basically consists of a transmitter and a
receiver. The transmitter consists of a high frequency oscillator, which produces an
oscillations of 1500 Hz at 15V. The receiver receives this frequency signal. If there
is any presence of metal in the coal. Then this frequency is disturbed and a
tripping signal is send to relay to stop the conveyor belt.
 Belt Weightier: It is used to keep an account of the tension on the belt carrying
coal and is moves accordingly to release tension on the belt.
 Reclaim Hopper: Reclamation is a process of taking coal from the dead storage
for preparation or further feeding to reclaim hoppers. This is accomplished by belt
conveyors.

AVISHEK GHOSH 18
F.D. FAN P.A. FAN
 Wagon Tippler: Coal from the coal wagons
is unloaded in the coal handling plant. This
unloading is done by the “Tipplers”. This
coal is transported up to the raw coal
bunkers with the help of conveyor belts.
 Crush House: After hand picking foreign
material, coal is transported to the Crush
house by conveyor belts where it is crushed
to small pieces of about 20 mm diameter.
The crushed coal is then transported to the
store yard. Coal is transported to bowl mills
by coal feeders.
WagonTipplerCrushHouse
 Blow Mill: The coal is pulverized in the
bowl mill, where it is grounded to a powder
form. The mill consists of a round metallic
table on which coal particles fall. This table
is rotated with the help of a motor. There
are three large steel rollers, which are
spaced 120” apart. When there is no coal,
these rollers do not rotate but when the
coal is fed to the table it packs up between
rollers and the table and these forces the
rollers to rotate. Coal is crushed by the
crushing actions between the rollers and
rotating tables.
BlowMill
 Furnace: This crushed coal is taken away
to the furnace through coal pipes with the
help of hot and cold air mixture from P.A
Fan. P.A Fan takes atmospheric air, a part
of which is sent to Air pre-heaters for
heating while a part goes directly to the
mill for temperature control. Atmospheric
air from F.D Fan is heated in the air
heaters and sent to the furnace as
combustion air.


AVISHEK GHOSH 19
P.A. Fan F.D. Fan I.D. Fan
No. of Fans
per Boiler
Motor Type Rating
(KW/HP)
Rated
Voltage
P.F. at Full
Load
Rated
Speed
5 3 Phase AC
50Hz IM
235/315 6.6KV 0.87 1490 RPM
No. of Fans
per Boiler
Rating
(KW/HP)
Rated
Voltage
P.F. at Full
Load
Rated Speed
2 270/362 6.6 KV 0.85 985 RPM
No. of Fans
per Boiler
Rating
(KW/HP)
Rated
Voltage
P.F. at Full
Load
Rated Speed
2 450/603 6.6 KV 0.85 740 RPM
Coal is pulverized in order to increase its surface its surface exposure thus promoting
rapid combustion without using large quantities of excess air. In modern power plants,
lump coal, crushed to uniform size is continuously supplied to the pulverized
hopper from where it is fed into the pulverized through a feeder arrangement.
Combustion rate is controlled by varying the feeder speed thereby controlling the rate of
coal being fed to the pulveriser. It is swept out from the mill and floated to the burner
located in the furnace wall by admitting enough of the combustion air at the pulveriser
to accomplish air bone transportation. This air is called primary air as it is varied from as
little as 10% to almost the entire combustion air requirements, depending upon load.
 P.A. Fan
 F.D. Fan
 I.D. Fan

AVISHEK GHOSH 20
Model of pulverizing millPulverizing Mill In operation
Ring Granulator

AVISHEK GHOSH 21
RH1 ECL
RH2 ICML,ECL
RH3 ICML
The no of convert belt 18
It’s area Wagon tippler to bunker
Crusher speed 750rpm
Shaft per crasher 4
The no of hammers inside the shaft 18
The no of Gates 19
The no of bunker per unit 5
The no of wagon per bunker 5
The height of bunker 60
Timing of to fill up a bunker 30 to 45 min
Bunker division 1 ECL coal Bunker 4 ICML coal Bunker
Ability of supply of coal in a bunker 14-15 hours
Time require for transport of coal from
Wagon tippler to bunker
5-6 min

AVISHEK GHOSH 22
Boiler used in the power plant is suspended type. This prevents it from getting deformed,
when a subjected to very high temperatures. The boiler is divided into two cylindrical parts
namely the Primary and the Secondary boiler. Water from the boiler feed pump passes
through economizer and reaches the boiler drum. Water from the drum passes through
down comers and goes to bottom ring header. Water from the ring header is divided to all
the four side of furnace. Due to heat and density difference the water rises up in the
water wall tubes. Water is partly converted to steam as it rises up in the furnace. This
steam and water mixture is again taken to the boiler drum where the steam is sent to super
heaters for superheating.
The super heaters are located inside the furnace and the steam is superheated (540°C) and
finally it goes to turbine. Flue gasses from the furnace are extracted by induced draft fan,
which maintains balance draft in the furnaces with forced draft fan. These flue gasses emit
their heat energy to various super heaters in
the pant house and finally pass through air
pre-heaters and goes to electrostatic
precipitator where the ash particles are
extracted. Electrostatic precipitator consists
of metal plates, which are electrically
charged. Ash particles are attracted on to
these plates, so that they do not pass
through the chimney to pollute the
atmosphere. Regular mechanical hammers
blows cause the accumulation of ash to fall
to the bottom of the precipitator where the
bottom of the precipitator where they are
collected in a hopper for disposal. This ash is
mixed with water to form slurry and is
pumped to ash pond.
BOILER
Types of firing:
 Perfect mixing of air & fuel
 For complete combustion the optimum fuel &air ratio is maintained.
 Continuous and reliable ignition of fuel.
 Adequate control over point of formation& accumulation of ash when coal is fuel.

AVISHEK GHOSH 23
STEAM DRUM:
The steam drum is made up of high cast steel so that its thermal stress is very high. There is a
safety valve in the drum, which may be explored if the temperature and the pressure of the
steam are beyond to a set value.
The boiler drum has the following purpose:
 It stores and supplies water to the furnace wall headers and the generating tubes.
 It as the collecting space for the steam produced.
 The separation of water and steam tube place here.
 Any necessary blow down for reduction of boiler water concentration is done from the drum.
Length Weight O.D. Design Press Shell
Thickness
Design
Temp
Head
Thickness
12.93 Mts 56 Tons 1724 mm 102.7 Kg/cm2 105 mm 312 C 90 mm
Steam pressure - 91.4kg/cm2
Steam temperature - 515o
C
Furnace volume - 1558m3
Drum Length 14.97m
Pressure 102.7kg/cm2
Temperature 312o
C
Type Ball & race
Pulveriser Capacity 15T/hr * 5
Speed 49rpm
Required power 100KW
Feeder Type Drag link
Control device Thyristor

AVISHEK GHOSH 24
RISER AND DOWN COMERS:
Boiler is a closed vessel in which water is converted into the steam by the application of the
thermal energy. Several tubes coming out from the boiler drum and make the water wall
around the furnace.
Outside the water wall there is a thermal insulation such that the heat is not lost in the
surroundings. Some of the tubes of the water wall known as the ‘down comer’, which
carries the cold water to the furnace and some of other known as the ‘riser comer’, which
take the steam in the upward direction. At the different load riser and the down comers
may change their property. There is a natural circulation of water in the riser and the
down comers due to different densities of the water and the steam water mixture. As the
heat is supplied, the steam is generated in the risers due to this density of the steam
water mixture is greater in the riser then in the down comer and the continuous flow of
water takes place. Down comer connected to the ‘mud drum’, which accumulates the mud
and the water. When the plant takes shut down the mud drum is allowed to clean
manually.
BURNERS:
15 Y jet sprayers are provided for lighting up and PF flame stabilization of 15 numbers burners.
There is a provision for firing both the heavy fuel oil and light diesel oil. The oil firing is done
initially during the starting up and when the coal used in TGS is of poor quality, then the plant is
allowed to run on oil support. In TGS light diesel oil (LDO) is used for the initiation for ignition of
the pulverized coal. The LDO charged into the furnace
through the oil burners. It increases the burning
capacity of the pulverized coal.
Heavy fuel oil passes through the pumping and
heating unit to reduce the viscosity as required for
firing. For LDO no heating is required. Separate oil
pumps are provided for LDO.

AVISHEK GHOSH 25
For both the type of oil, the oil pump discharge a pressure is 14 kg cm². Constant steam
pressure 10.5 kg cm² is maintained for oil atomization and oil heating. P 34 gas igniters are
provided for ignition.
SUPER HEATER:
The super heater rises the temperature of the steam above its saturation point and there are
two reasons for doing this:
FIRST- There is a thermodynamic gain in the efficiency.
SECOND- The super-heated steam has fewer tendencies to condense in the last stages of the
turbine.
ECONOMISER:
The heat of the flue gas is utilized to heat the
boiler feed water. During the start up when no
feed water goes inside the boiler water could
stagnate and over heat in the economizer. To
avoid this economizer re-circulation is provided
from the boiler drum to the economizer inlet.
SAFETY VALVE:
A safety is a valve mechanism for the automatic release of a gas from a boiler, pressure
vessel or other system when the pressure or temperature exceeds pre-set limits. It is a part
of a bigger set named Pressure Safety Valve (PSV) or Pressure Relief Valve (PRV). The other
parts of the set are named relief valves.

AVISHEK GHOSH 26
AIR HEATER or AIR PREHEATER:
The air heater is placed after the economizer in the path of the boiler flue gases and preheats
the air for combustion and further economy. There are 3 types of air pre heaters: Tubular
type, rotary type and plate type. Tubular type of air
heater is used in TGS. Hot air makes the combustion
process more efficient making it more stable and
reducing the energy loss due to incomplete
combustion and unburnt carbon. The air is sucked by
FD fan heated by the flue gas leaving the
economizer. The preheated air is sent to coal mill as
primary air where coal is pulverized. The air sucked is
heated to a temp. Of 240-280o
C. The primary air
transports the pulverized coal through three burners
at TGS after drying in the mill.
SPRAY ATTEMPERATOR:
In order to deliver a constant steam temperature over a range of load, a steam generating
unit (Boiler) may incorporate a spray attemperator. It reduces the steam temperature by
spraying controlled amount of water into the super-heated steam the steam is cooled by
evaporating and super heating the spray water. The spray nozzle is situated at the entrance
to a restricted venture sections and introduces water into the steam. A thermal sleeve
linear protects the steam-line from sudden temperature shock due to impingement of the
spray droplets on the pipe walls. The spray attemperator is located in between the primary
super heater outlet and the secondary super heater inlet.

AVISHEK GHOSH 27
Turbine is a rotating device which converts heat energy of steam into mechanical energy. It is
a two cylinder machine of impulse reaction type comprising a single flow high pressure turbine
and a double flow low pressure turbine. The H.P. turbine shaft and the generator are all rigidly
coupled together, the assembly being located axially by a thrust bearing at the inlet end of H.P.
turbine.
The turbine receives high pressure steam from
the boiler via two steam chests. The H.P.
turbine cylinder has its steam inlets at the end
adjacent to the no. one bearing block, the
steam flow towards the generator. Exhaust
steam passes through twin over-head pipes to
the L.P. turbine inlet belt where the steam
flows in both directions through the L.P.
turbine where it exhausts into under slung condenser. Steam is extracted from both the
H.P. & L.P. turbine at various expansion stages & fed into four feed water heaters.
Main parts of a Turbine –
TURBINE
 Over speed trip test plunger
 Over speed governor
 Worm
 Speed indicator wheel
 Breaking keep-no.1
 Thrust collar
 Bearing and thrust-no.1
 Oil buffle-no.1
 Labyrinth gland-no.1
 Dummy piston
 Nozzle chest
 Impulse wheel
 H.P. Turbine shaft
 Reaction blading
 Labyrinth gland-np.2
 H.P. Exhaust
 Oil buffle-no.2
 Casing and block head

AVISHEK GHOSH 28
The steam coming out of the turbine no longer remains superheated, so this warm steam is
allowed to condense for recycling inside the condenser. The condensate is extracted from the
condenser extraction pump. This extraction should be kept free from the air & air rejecter.
Pipes serve this purpose. Then water from CEP enters
the drain cooler and warm water is cooled there and
increases boiler efficiency. In the drain cooler it gets the
temp. 0f 47o
C & enters the L.P. heater 1, where water
temp. increases to 70o
C and then it enters the L.P.
heater 2 n the temperature becomes 102o
C
It has several functions.
 To condensate the steam exhausted from the L.P. turbine.
 To accept & condense the steam from drains &vents of heaters through flush box.
 To maintain the vacuum.
 To accommodate the air and non-condensable gases in the coolest zone of the condenser.
 To receive make up water for the system & de-aerate the same.
 To act as reservoir for the extraction pump.
Economical and max continuous rating 60MW
Steam pressure at emergency stop valve 89kg/cm2
Steam temperature at emergency stop valve 510o
C
Absolute pressure at exhaust 0.088kg/cm2
Rotational speed 3000rpm
Tripping speed 3375rpm
CONDENSER

AVISHEK GHOSH 29
Alternator generates electricity. In general the electrical and magnetic circuits of the
generator are of conventional design. The generator stator casing contains the core and
windings which are enclosed at the ends with inner and outer and covers. At both sides of
casing, air coolers are mounted on the generator soleplate and connect to a re-circulatory
air ventilation system. The covers over the coolers direct air to and from the generator
casing via the air coolers. Two axial flow fans, one at each end of the rotor circulate the
cooling air through the generator and air coolers.
The generator rotor, when excited, provides the magnetic field for the generator. The shaft
is hollow bored at the exciter end and machined to carry the rotor winding. The rotor is
threaded through the bore of the generator stator and is supported at each end by a white
metal bearing. The alternator and main exciter are of the brushless type and copper links,
connect the rotor winding to a rotating rectifier on the main exciter shaft.
ALTERNATOR

AVISHEK GHOSH 30
MAIN EXCITER PILOT EXCITER
Maximum continuous rating 60 MW output
Maximum continuous rating 70.59 MVA o/p
Rated power factor 0.85 lagging
Rated terminal voltage 10500 volts
Rated phase current 3881 amps
Rated speed 3000 rpm
Frequency 50Hz
Number of phases 3
Number of poles 2
Short circuit ratio 0.6
Anti-condensation heater rating 6off-1KW,415V,3ph,4wires 50Hz
Number of phase 1
Rated peak voltage 130V rms
Power factor peak 0.9 Y -
Connection
Number of poles 8
Maximum continuous rating 207KW
Rated terminal volt at
rectifier DC term
225V
Rated current at rectifier 920A
Frequency 150Hz
Rated speed 3300 rpm
Number of poles 6

AVISHEK GHOSH 31
It is a device that separates fly ash from outgoing flue gas before it discharged to the stack.
There are four steps in precipitation.
 Ionization of gases and charging of dust particles.
 Migration of particle to the collector.
 Deposition of charged particles on collecting surface.
 Dislodging of particles from the collecting surface.
By the electrostatic discharge the ash particles are charged due to high voltage (56KV)
between two electrodes. Generally maximum amount of ash particles are collected in the
form of dry ash, stored inside the SILO. Rest amount of ash (minimum) are collected in the
form of bottom ash and stored under the water inside HYDROBIN
Control Circuit:
To control the operation & protection of the control circuit is provided which comprises the
following modules:
 Ramp setting
 Power supply
 Power amplifier
 Synchronizing & firing module
 Flashing over sensing
 Under alarm & voltage annunciation
ELECTRO-STATIC PRECIPERATOR

AVISHEK GHOSH 32
Operation of E.S.P:
Steady state load operation: During steady state resistance load it is a DC power supply
with a constant current, constant voltage characteristics where the limiting parameter can be
set under manual mode of operation. The limiting actions of parameters is achieved by
controlling the triggering angle of the thirstier of AC regulator.
Operation under Flashover Condition: When the spark occurs it is sensed & a common signal
is given to the reference by a set amount which in turn reduces the output voltage proportionally.
Dust of fly ash gets deposited in the plates which has to be regularly removed by doing raping.
Seven raping system is continuously operating through the microprocessor.

AVISHEK GHOSH 33
Bottom Ash Removal System: Here for removal
bottom ash “Zero Discharge System” is used. In this
system overflow transfer tank, overflow transfer
pump, two numbers of hydro bin, one number of
settling tank, one number of surge tank, three HP
pumps, two LP pumps, ejector and three number of
surge recirculation pumps are present.
The bottom ash hopper filled with the water. When
the bottom ash come into the contact of water it
forms clinker then the ash passes through flap gate
and goes to the clinker grinder to reduce the size
of the clinker formed ash. After clinker grinder it goes
to the ejector where power water create the jet
velocity to convey the bottom ash to the hydro bin.
Hydro bin is a conical shaped tank which can separate
the ash and the water. Here two numbers of hydro bin
are used. When one hydro bin is filled with the ash
other come into the service. Each hydro bin can store
four days ash. In the hydro bin a horizontal plate is
present that is baffle plate upon which the mouth of
the slurry pipes are opened. There is a little gap between the plate and the mouth of the pipe.
When the slurry water comes out from the pipe and falls on the plate the turbidity is reduced.
It helps the slurry water to settle down the ash at the bottom. The ash settle down in the
bottom and the water (not pure) is comes out from the vertical cylindrical centralised strainer.
ASH REMOVAL SYSTEM

AVISHEK GHOSH 34
The water from the upper most portion of the hydro bin means overflow water comes out and
goes to the settling tank for more settlement of ash. In the bottom portion there is a flap gate
for ash extraction through this gate the ash is collected in the truck to dispatch. In the surge
tank more ash is separated and this bottom ash is conveyed to the hydro bin through another
SRP. There is no overflow facility of the surge tank. The clear water from surge tank through
three number of HP pumps goes to the ejector as power water to convey the bottom ash.
Similarly, two LP pumps also connected with the surge tank. It convey the water to the
bottom ash hopper for sealing purpose. The overflow water of the bottom ash hopper goes
to the hydro bin through overflow transfer tank and overflow transfer pump. Here no water
comes out from the system. For this reason this system is called ““Zero Discharge System””.

AVISHEK GHOSH 35
Resistance temperature detectors (RTDs): Resistance thermometers, also
called resistance temperature detectors (RTDs), are sensors used to measure temperature
by correlating the resistance of the RTD element with temperature. Most RTD
elements consist of a length of fine coiled wire wrapped around a
ceramic or glass core. The element is usually quite fragile, so it
is often placed inside a sheathed probe to protect it. The
RTD element is made from a pure material, typically platinum, nickel or
copper. The material has a predictable change in resistance as the temperature changes
and it is this predictable change that is used to determine temperature.
Thermistor: A thermistor is a type of resistor whose resistance varies significantly
with temperature, more so than in standard resistors. Thermistors differ from resistance
temperature detectors (RTDs) in that the material used in a
thermistor is generally a ceramic or polymer, while RTDs use pure
metals. The temperature response is also different; RTDs are
useful over larger temperature ranges, while thermistors typically
achieve a higher precision within a limited temperature range,
typically −90 °C to 130 °C.
Orifice plate: An orifice plate is a device used for
measuring flow rate, for reducing pressure or for
restricting flow (in the latter two cases it is often called
a restriction plate). Either a volumetric or mass flow
rate may be determined, depending on the calculation
associated with the orifice plate.
BASIC INSTRUMENTS AT TGS

AVISHEK GHOSH 36
Thermocouple: A thermocouple is a temperature-
measuring device consisting of two dissimilar
conductors that contact each other at one or more
spots. It produces a voltage when the temperature
of one of the spots differs from the reference
temperature at other parts of the circuit.
Thermocouples are a widely used type
of temperature sensor for measurement and control, and can also convert a temperature
gradient into electricity.
Smart transducer: A smart transducer is an analog or
digital transducer or actuator combined with a processing
unit and a communication interface. As sensors and
actuators become more complex they provide support for
various modes of operation and interfacing .Some
applications require additionally fault-tolerance and distributed computing. Such high-level
functionality can be achieved by adding an embedded microcontroller to the classical
sensor/actuator, which increases the ability to cope with complexity at a fair price. They are
often made using CMOS, VLSI technology.
Pressure measurement: Many techniques have been developed for the measurement
of pressure and vacuum. Instruments used to measure pressure are called pressure
gauges or vacuum gauges.
Bourdon: - The Bourdon pressure gauge uses the principle that
a flattened tube tends to straighten or regain its circular form in
cross-section when pressurized.
Bourdon

AVISHEK GHOSH 37
Titagarh Generating Station currently runs on Distributed Control System (DCS).
A distributed control system (DCS) refers to a control system usually of a manufacturing
system, process or any kind of dynamic system, in which the controller elements are not
central in location (like the brain) but are distributed throughout the system with each
component sub-system controlled by one or more controllers. The entire system of
controllers is connected by networks for communication and monitoring.
A DCS typically uses custom designed processors as controllers and uses both proprietary
interconnections and communications protocol for communication. Input and output
modules form component parts of the DCS. The processor receives information from input
modules and sends information to output modules. The input modules receive information
from input instruments in the process (a.k.a. field) and transmit instructions to the output
instruments in the field. Computer buses or electrical buses connect the processor and
modules through multiplexer or demultiplexers. Buses also connect the distributed
controllers with the central controller and finally to the Human-Machine Interface (HMI) or
control consoles.
A typical DCS consists of functionally and/or geographically distributed digital controllers
capable of executing from 1 to 256 or more regulatory control loops in one control box.
The input/output devices (I/O) can be integral with the controller or located remotely via
a field network. Today’s controllers have extensive computational capabilities and, in
addition to proportional, integral, and derivative (PID) control, can generally perform logic
and sequential control.
DISTRIBUTED CONTROL SYSTEM

AVISHEK GHOSH 38
DCSs may employ one or several workstations and can be configured at the workstation or
by an off-line personal computer. Local communication is handled by a control network
with transmission over twisted pair,
coaxial, or fiber optic cable. A server
and/or applications processor may
be included in the system for extra
computational, data collection, and
reporting capability.

AVISHEK GHOSH 39
CONCLUSION
CESC’s environmental management system focuses on continuous improvement and
upgradation with state-of-the-art principles and equipment, setting high targets and
reviewing its performances. CESC recognizes its responsibility towards protecting the
ecology, health and safety of the employees and consumers.
The vacational training has been organized by the CESC limited and has been undertaken
at the Titagarh Generating Station. The purpose of the vocational training is to get an
industrial exposure in our engineering career.
Students can learn a lot from different books about various subjects such as operations
of a plant, various constituents of a plant, power production, power distribution etc. but
a practical experience helps in better understanding and enhancement of knowledge in
various subjects. I am grateful to CESC limited for organizing this vacational training.

AVISHEK GHOSH 40
This is to certify that Mr. Avishek Ghosh, student of 3rd
year Mechanical Engg.
Dept. Jadavpur University, has successfully completed his 2 weeks Vacational Training at
Titagarh Generating Station, CESC Limited, B.T.Road, Khardah, North 24-Parganas, WB,
PIN-700119 from 13th
June to 25th
June 2016.
He was punctual and his conduct during the training was good. I wish him
success in his future carrier.
Mr.Hirak Das Date
(Asst. Manager HRD)
DECLARATION
Name of Trainee – Avishek Ghosh
Class – 3rd year B.E. Mechanical
Name of College – Jadavpur University
Duration of Training – 13/6/16 – 25/6/16
Place of Training – Titagarh Generating Station

CESC-TGS REPORT

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