Thermal Power Station Ukai Report pdf 24

Collage Institute Provided By Internship Training GSECL,UKAI.

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INTERNSHIP REPORT




 GUJARAT TECHNOLOGICAL UNIVERCITY
AHEMDABAD


 VIDHYADEEP INSTITUTE OF ENGINEERING AND
TECHNOLOGY, ANITA, KIM





Internship In THERMAL POWER STATION,GSECL
UKAI
In partial fulfilment for the award of the degree of
DEPLOMA OF ENGINEERING
IN
MECHANICAL DEPARTMENT
3
rd
Semester
Submitted by
NAME ENROLLMENT NO
VASAVA ANISH SARVARSHING 229630319013

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 VIDHYADEEP INSTITUTE OF ENGINEERING AND TECHNOLOGY,
ANITA, KIM



 DECLARATION


I hereby declare that the internship report submitted along
with the internship at THERMAL POWER STATION, UKAI
submitted in partial fulfilment for the Diploma of Engineering
in Mechanical Engineering to Gujarat Technological
University, Ahmedabad is a benefited record of original
project work carried out by me at THERMAL POWER
STATION, UKAI under the supervision of B.B Chaudhari And
there is no part this report has been directly copied from any
students report or taken from any other source without
providing dug reference.

Name of Student : Sig. of Student :
Vasava Anish. S

Name of H.O.D : Sig. of H.O.D.
Kavaljitsinh. J. Kosamiya

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 ACKNOWLEDGEMENT


We are gladly thankful to our H.O.D. and our staff
members who give us a great guidance regarding training and
instruct us the importance of training in mechanical field so we
decided to take training in THERMAL POWER PLANT which is
situated at UKAI.

We are especially thankful to respected chief engineer,
Training Centre, UKAI THERMAL POWER STATION because we
granted permission to take training in this such wonderful
campus.

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 INDEX


Sr.No. NAME Page.
No.
1. ABSTRACT 5
2. INTRODUCTION 6
3. BLOCK DIAGRAM OF THERMAL POWER PLANT 7
4. BOILER DETAIL 9
5. TURBINE DETAIL 14
6. CONDENSER 15
7. COOLING TOWER 16
8. DRAUGHT SYSTEM 19
9. COAL HANDALING PLANT 24
10. ASH HANDALING SYSTEM 30
11. GENERATOR DETAIL 33
12. TRANSFORMER DETAIL 34
13. DM PLANT 35
14. CONCLUSION 36

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1. ABSTRACT

 The main aim this training is to study the various types of
mechanical instrument involved in the process of generation
of electrical power.
 We decided to take training to improve practical knowledge
and get benefit their theoretical knowledge.
 An internship is a purposeful activity of the student set in a
work environment in order to obtain learning outcomes
within their curriculum. During the internship, the
knowledge, skills, and attitudes learned in the programmed
can be applied.
 The aim of the internship provides a direction to the
activities, helps to focus on a result, and to assess the result
achieved.
 Connecting what you have learned (theoretical and practical
knowledge on your subject field) with actual work
experience, in order to complement your field specific skills
and learn new ones.
 The internship is a process to achieve practical
knowledge about some theoretical lessons. Basically, an
internship means having practical knowledge from a real
scenario of work.

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2. INTRODUCTION


 Ukai Thermal Power Station of the Gujarat State Electricity
Corporation Limited, India.
 Is a power station with an installed capacity of 1,110 MW. It
is one of Gujarat's major coal-fired power plants, located on
the bank of the Tapi river.
 Ukai Thermal Power Station is located on the banks of
the Tapi because of the water resources, along with the
hydroelectric power plant with the same name.

Ukai TPS
Unit-1 is the first power station unit in India with a capacity
more than 100 MW.

 Installed Capacity :










 Ukai TPS unit-6 was first unit in GSECL having a capacity
more than 500 MW.

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3. BLOCK DIAGRAM’S OF THERMAL
POWER PLANT















i. Feed Water & Steam Flow Diagram

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ii. Energy Balance

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4. BOILER DETAILS


 Stage I & II: Tangentially Fired, Balance Draft, Natural
Circulation, Radiant Reheat Type.
 Stage III: Vertically Suspended Water Tubes, Radiant Reheat
Cycle, Natural Circulation.
 Height of Boiler: 64 m
 Capacity: 700 Tones/hr.
 Feed Water Temp.: 241°C
 Steam Temperature: 540°C
 Force Draft Fan: 2 Nos
 Induced Draft Fan: 2 Nos
 Primary Air Fan: 2 Nos
 Coal mill: 6 Nos
 Steam Pressures at Boiler Outlets:
[1] SH: 137 Kg/Cm²
[2] RH: 25.8 Kg/Cm²
 Height Of Chimney: Stage 1&2 150 m Stage 3 220 m

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İ. Economizer


 The feed water from the high-pressure heaters enters the
economizer and pick up heat from the flue gases after the low
temperature super heater.
 The boiler designer always keep the economizer water outlet
temperature to about 25-35 degrees below the drum
saturation temperature.
 Economizer tubes are commonly 38.1x4 mm in OD and made
in vertical sections of continues tubes between inlet and
outlet headers with each sections formed into several
horizontal paths connected by 180° bend for proper drainage.
 Economizer are generally placed between the last super
heater, reheater and the air preheater.
 Chemical and water washing when cleaning the economizer
in shut down time of the station.

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İİ. Super Heater



 It is integral part of the boiler and is placed in the path of hot
flue gases from the furnace.
 The heat recovered from the flue gases is used in
superheating the steam before entering into the turbine.
 Its main purpose is to increase temperature of saturated
steam without raising its pressure.
 In UKAI, TPS the regenerative super-heater are used.


















İİİ. Air Pre-Heater

 The purpose of the air preheater is recover the heat from the
heat from the boiler flue gases.
 It increases the thermal efficiency of the boiler by reducing
the useful heat lost in the flue gas.
 Air preheaters are also a requirement for the operation of
pulverized-coal furnaces to dry that fuel.

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İV. Re-Heater

 They are the same as the super-heaters but as their exit
temperature is a little bite less than super heater and their
pressure is 20%-25% less than the super-heater.
 Re-heater tube are commonly 44.5×5 mm in OD


V. High-Pressure Feed Heater

 The high-pressure feed heater is a heat exchanger of the
shell and tube which further heats the feed water before
entry to the boiler.
 Bled steam from the turbine is used for heating.


Vİ. Low-Pressure Feed Heater

 Feed Water from the condensate extraction pumps passes
through five low pressure feed heaters.
 Steam is used to heat the feed water. After the fifth low
pressure heater, the feed water is at 160 c.

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Vİİ. Steam Drum

 After leaving the economizer, the feed water reaches the
steam drum, which is cylindrical vessel at the top of the
boiler.
 From here the water flows by natural circulation through
downpipes into the boiler. Saturated steam collects here
ready to go to the SH.

































[STEAM DRUM]

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5. TURBINE DETAILS


 Turbine Consist of multi stage three cylinder with lube oil
system, Jack Oil Pump, bearing lubrication, condenser, LP
Heaters, Gland coolers, HP Heaters, Condensate extraction
pumps, Deaerators, CW system and other auxiliaries.

 Type: Three Cylinders Condensing Tandem, Compound
Horizontal Reheat Type.
 Makes: Stage 1- Russian/Lenin Grade Metal Works (LMW)
Design.
Stage 2- German Craft Work Union (K.W.U) Design
 High Pressure (HP) Turbine (first cylinder)-
Steam Inlet Temperature-535 C
Steam Inlet Pressure 130 Kg/cm2
 Intermediate Pressure (IP) Turbine (Second Cylinder)-
Steam Inlet Temparature-535 C
Steam Inlet Pressure 26 kg/cm2
 Low Pressure (LP) Turbine (Third Cylinder)-
It used steam of very low pressure and temperature.

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6. CONDENCER

 The Surface Condenser are used in UKAI TPS.
 A Surface Condenser is a commonly used term for a water-
cooled shell tube heat exchanger which is installed on the
exhaust steam from a steam turbine.
 The primary purpose of a surface condenser is to condense
the exhaust steam from a steam turbine to obtain maximum
efficiency and also convert in pure water.
 These Condenser are heat exchanger which converts steam
from its gaseous to its liquid state at a pressure below
atmospheric pressure.
























[CONDENCER]

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7. COOLING TOWER

 Cooling towers are heat removal devices used to transfer
process waste heat to the atmosphere.
 Cooling towers may either use the evaporation of water to
remove process heat and cool the working fluid. The towers
vary in size from small roof-top units to very large
hyperboloid structures.
 Cooling tower is one type of heat exchanger.
 TYPE: Natural Draft Cooling Tower.
 Cooling Tower Heights:
Stage 1& 2: 112 m
Stage 3 & 4:118 m
 By using CEP (Condensate Extraction Pump) cold fluid is again
fed into condenser. And from condenser to cooling tower.
Cycle is again repeated.

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İ. Deaerator

 Function of Deaerator is to remove the dissolved gases
(oxygen & carbon Dioxide) in water.
 Presence of oxygen in water react with metal and to form
iron oxide.
 To provide net positive suction head (NPSH) for pump,
Deaerator located at sufficient height. When water sucked by
pump pressure does not fall Past and no flashing of water
into vapor, which protects BFP from damage & cavitation































[DEAREATOR]

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İİ. Boiler Feed Pump

 Boiler feed pump is a multi-stage pump provided for
pumping feed water to economizer. BFP is biggest auxiliary
equipment after boiler and turbine. It consume about 4 to 5
MW electricity.by using booster pump we can increase
pressure about 35 kg/cm².
 Then BFP increase the pressure about 150 kg/cm². And this
high-pressure water again fed into the economizer.






























[BOILER FEED PUMP (B.F.P.)]

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8. DRAUGHT SYSTEM

 The difference between atm pressure and pressure existing
in furnace is termed as draft.
 In a power plant large amounts of air are needed for
combustion of fuel. And huge amount of combustion
products (flue gases, ash) have also removed from boiler so
that pressure differential is needed. Draught is used to define
static pressure in furnace, ducts.




İ. Tow Main Function of Draught System

1) Supply required quantity of air for complete combustion of fuel
2) Remove gaseous products of combustion from furnace & throw
through chimney to atmosphere.

 Mechanical draught is produced by fans. Mechanical draught
equipment much more economical. Two types of fans used in
power plant (1) FD Fan (2) ID Fan.

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İİ. Forced Draught

 Function of the FD fan is to supply secondary air to the
windbox. Forced draught fans are installed at inlet to air
preheater. They handle cold air or say atm air. FD Fan forcing
air into the furnace and ductwork. Air is often passed
through an air heater; which heats the air going into the
furnace in order to increase the overall efficiency of the
boiler. Dampers are used to control the quantity of air
admitted to the furnace. Forced draught furnaces usually
have a positive pressure. Two FD Fans are used in parallel say
A & B. Centrifugal fans with backward-curved blading type is
used in power plant.

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İİİ. Induced Draught

 ID Fans are generally located at the end of ESP (Electro Static
Preceptor). induced draught fan (ID fan) which removes flue
gases from the furnace and forces the exhaust gases up to
the chimney. Induced Draught furnaces usually have a
slightly negative pressure. Two ID Fans are used in parallel
(say A & B) for better reliability. Centrifugal fans with
forward-curved or flat blading is used in pp. ID fan creates
negative draft inside furnace -5 to -10 mmwc.

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İV. Balanced Draught

 Balanced draught is obtained through use of both induced
and forced draught.
 This is more common with larger boilers where the flue gases
have to travel a long distance through many boiler passes.
 The induced draught fan works in conjunction with the
forced draught fan allowing the furnace pressure to be
maintained slightly below atmospheric.
 Balanced draft pressure is required because furnace were
not air tight, furnace walls were cooled by constant stream of
cool air drawn in slightly negative pressure.
 if allowing these furnace to go positive for even a short time
could result into damage boiler. If boiler operate with
excessively negative pressure than too much air through
furnace. Resulting poor burner and poor efficiency.

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V. Primary Air Fan

 Main function of PA fan is to carry coal from pulverize to
furnace and also heating of coal so that moisture present in
coal can be removed and coal can be easily burnt out in
furnace. Discharge of pa fan divided into two parts first one is
cold pa and second one is hot pa after passing through air
preheater which is utilize for transformation of coal from
pulverize to furnace.




















[PRIMARY AIR FAN]

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9. COAL HANDALING PLANT

 A coal-handling plant (CHP) in a thermal power plant is a
front-end facility with a primary function, In a nut shell, that
is to receive coal and transfer it the coal bunker. The proper
coal size should be what is acceptable to the mills/pulverizes
for further processing. There are quite a few factors that
dictate the design of the CHP (e.g., coal source, coal quality
and size, transportation mode, main plant capacity),
topography of the area, etc. The coal supplied directly from
the mine to the various destinations (e.g., coal preparation
plant, coal washeries, steam generation plant) is called run-
of-mine, or ROM, coal. This coal contains rocks, other
minerals, and a variety of contaminations…














[COAL HANDLING SYSTEM]

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İ. Coal Circuit

 UKAI POWER STATION is coal based power station.it uses
coal as its fuel. Bituminous coal is used in the UKAI POWER
STATION. UKAI received coal mainly from coal mines
situated at Orissa, Madhya Pradesh, west Bengal, Andhra
Pradesh, Chhattisgarh Mines ( south eastern collieries Ltd),
WCL(Western Collieries Ltd) & Korea reva mines.
 To unload received coal rack, UKAI THERMAL POWER
STATION has wagon tippler house. There are total 05 no of
tipplers which unloads record 710 nos of wagon in single day.
 Total 5 wagon tipplers installed. 1,2,4 are made by elechon &
tippler 5 is hydraulic.
 5 to 7 rack received per day.
 Each railway train carrying 58 wagons is called one rack. Each
wagon loads 60 ton of coal which means each rack loads
3600 MT Approx.. Total 18000 MT-21000 MT of coal is
consumed daily to generate power of 1,110 MW.

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 Light diesel oil (LDO) is also used for lighting up the boiler at
the time of start up.
 The steps involved in coal handling are as follows:

1. Coal delivery
2. Unloading
3. Preparation
4. Transfer
5. Outdoor storage
6. Covered storage
7. In Plant Handling
8. Weighing and Measuring
9. Feeding The Coal Into Furnace.





İİ. Coal Delivery

 The coal from supply points is delivered by Orissa, Madhya
Pradesh, west Bengal, Andhra Pradesh, Chhattisgarh Mines
(south rail ways to power stations. generally, from eastern
collieries Ltd), WCL (Western Collieries Ltd) & Korea reva
mines.

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İİİ. Belt Conveyor

 It is moving over a pair of end drums roller. At some distance
a supporting roller is provided at the center. The belt is
made, up of rubber & nylon. It is suitable for the transfer of
coal over long distances. The inclination at which coal can be
successfully elevated by belt conveyor is about 20.
 Total length of conveyor belt is around 16 km. width of
conveyor belt is 1500mm, 1400mm &1200mm. belt speed is
3.3-3.6 m/sec.


İV. Stockpiles

 Stockpiles provide surge capacity to various parts of the CPP.
ROM coal is delivered with large variations in production rate
of tones per hour (tph). A ROM stockpile is used to allow the
wash plant to be fed coal at lower, constant rate. A simple
stockpile is formed by machinery dumping coal into a pile,
either from dump trucks, pushed into heaps with bulldozers
or from conveyor booms. More controlled stockpiles are
formed using stackers to form piles along the length of a
conveyor, and reclaimers to retrieve the coal when required
for product loading, etc. Taller and wider stockpiles reduce
the land area required to store a set tonnage of coal. Larger
coal stockpiles have a reduced rate of heat lost, leading to a
higher risk of spontaneous combustion.

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V. Stacking

 Travelling, lugging boom stackers that straddle a feed
conveyor are commonly used to create coal stockpiles.
 1 MAMC (mining & Allied Machinery Corporation) stacking
capacity 2000 MT/hour.
 2 elechone stacking capacity 1000 MT/hour.


Vİ. Reclaiming

 Tunnel conveyors can be fed by a continuous slot hopper or
bunker beneath the stockpile to reclaim material. Front-end
loaders and bulldozers can be used to push the coal into
feeders. Sometimes front- end loaders are the only means of
reclaiming coal from the stockpile. High-capacity stockpiles
are commonly reclaimed using bucket-wheel reclaimers. two
types of reclaimer.

1. MAMC (Mining & Allied Machinery Corporation)
Reclaiming capacity 1500 MT/hour.
2. Elechone reclaiming capacity 750 MT/hour.

 Coal size is uneven, so that it is necessary that coal used in
plant is in powder form so better combustion of coal is
occurs.
 For this purpose two crusher is used.
1) Primary Crusher.
2) Secondary Crusher.

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 Primary crusher: in primary crusher size of coal is max about
125 mm. capacity of primary crusher is 1100 MT/hour. 1A,
1B, 1C,1D is installed.
 Secondary crusher: in secondary crusher size of coal is max
about 30mm.capasity of this crusher is nearly
1100MT/hour.2A, 2B, 2C, 2D is installed.
 Magnetic separators are provided in plant to remove iron or
uneven impurities in coal. Two magnetic separators are
provided.
 Now this coal is go into the bunkers with the help of
conveyor belt. There is total 6 bunkers. But only 4 is in
running condition. Hoppers are used to weigh the quantity of
coal.
 From bunkers this coal go into the feeders. And from feeders
to the mills or grinders or pulveriser. Total 6 mills are there.in
mill we gain coal powder. Stockers provided to feeds coal
into furnace this coal powder is lift by PA Fan and sprayed
into furnace. Orifice type arrangement is required to control
the quantity of coal into furnace.
 Bowl mill is used in UKAI TPS Thermal Power Plant.

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10. ASH HANDLING SYSTEM

 In Thermal Power Plants, an Ash Handling System is used to
collect and dispose off discharged Ash, once it has been
cooled down to a manageable temperature. Which is then
used in various industries like construction, cement plants,
and other allied industries. Typically for a 20x500 MW Plant
based on India coal, the amount of ash generated is around
300 to 400 TPH depending on gross calorific value and ash
content of the coal. The amount of ash produced when coal
is burnt in a thermal power plant is roughly thousands of
tonnes. It could have an effect on other subjects too if proper
ash handling methods are not followed.

1. Fly Ash Handling System
2. Bottom Ash Handling System
3. Ash Slurry Disposal System











[ASH HANDLING SYSTEM]

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İ. Ash And Flue Gases Circuit

 Ash disposal is the major problem in power plant.
 To avoid the atmospheric pollution the fly ash must be
removed from the gaseous products of combustion before
they leaves the chimney.
 ID Fan sucks the flue gases from boiler.
 Flue gases contains fly ash and other gases like SOx, NOx. So
that it is necessary to remove fly ash from flue gases.

 FLUE GASES PATH: -




























Boiler Furnace
Pre-Heaters
ESP
Air Pre-Heater
Economizer
Super Heaters
Chimney

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İİ. Electro Static Precipitator

 ESP (Electro Static Precipitator) is device that remove
particles from flue gases by using ID Fan charge.
 From air preheater flue gases goes to ESP. this precipitator
has plate blanks A,B,C,D,E,F which are insulated from each
other between which the flue gases are made to pass. Dust
particles are ionized and attracted by charged electrode are
maintained at 60KV.hammering is done to the plates so that
fly ash comes down and collect at the bottom the fly ash is
dry form is used in jp cement manufacture.
 Silo is also provided in plant.


























[ELECTRO STATIC PRECIPITATOR]

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11. GENERATOR DETAILS

 Type: THW-210-2B (Water & Hydrogen Cooled Turbo
Generator
 Rated Capacity: 210 MW, 247 MVA
 Power Factor: 0.85 Lag
 Stator: 15.75 Volts, 9050 A
 Rotor: 310 V DC, 2600 A
 Excitation System: Static
 Type of Cooling: Water, Hydrogen
 Hydrogen Pressure: 3.5 Kg/Cm2

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12. TRANSFORMER DETAILS

 Generator Transformer:

Stage 1: 250 MVA, 15.75/220KV
Stage 2: 250 MVA, 15.75/400KV
 Interconnection Transformer: 500 MVA (167 x 4, 3+1 St by),
220/400 KV
 Station Transformers: 25 MVA, 220/07 KV Unit Auxiliary
 Transformers: 15 MVA, 15.75 / 07 KV Unit Service
 Transformers: 07 KV/433 Volts Station Service
 Transformers: 02 MVA, 07 KV / 433 Volts

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13. DE MINERALIZATION (DM) PLANT

 Demineralization is the process of removing mineral salts
from water by using the action process.
 Basic Processes: -
1. Distillation
2. Membrane Filtration
3. Deionizing
4. Degasser
 In the Context of water purification, ion exchange resin. The
impurity ions are taken up by the resin.
 The following ions are widely found in raw water
1. Cations: -Calcium (Ca2+), Magnesium (Mg2+), Sodium
(Na+) Potassium (K+)
2. Anions: -Chlorine (CI), Bicarbonate (HCO3), Nitrate
(NO3-)


















[DM PLANT]

36. 36

13. CONCLUSION

 After this training at the UKAI THERMAL POWER STATION
we can visualized the complex study of power generation
using coal as a fuel, which will help us a lot in future in many
field & we can understand the function of each component in
THERMAL POWER STATION, their importance, their
arrangement & precautions that to be used for the safety in
the plant.
 We only say that we really enjoyed us training over here and
we again want to thank all my faculties, staff of UKAI
THERMAL POWER STATION to give us this great pleasure of
the training.
 At last we conclude that we got good knowledge and great
experience at the UKAI THERMAL POWER STATION.