NATIONAL THERMAL POWER CORPORATION Ltd.
PROJECT REPORT ON
500 MW
BOILERS
2023
NTPC Ltd., TSTPS, KANIHA, TALCHER
AT NTPC Ltd. ,TSTPS POWER PLANT,
KANIHA
GUIDED BY:
PRASANTA KUMAR BEHERA
SR.MANAGER(operation)
Emp No:100792
NTPC Ltd.,Talcher(kaniha)
SUBMITTED BY: BISWABIJAYIT JAGDEV
CERTIFICATE
This is to certify that the project report on “500 MW BOILERS by
BISWABIJAYIT JAGDEV, Regd. No:-F22004002014 (INDIRA
GANDHI INSTITUTE OF
TECHNOLOGY,SARANG), is carried out under my guidance, in partial fulfillment of
summer vocational training from 1st July,2023 to 31st July, 2023. The present
work is a sincere and dedicated effort to study the various design and
operational aspect of high-pressure feed-water heaters and the regenerative
cycle of a power plant. During the course of training I found
Mr. Jagdev to be hard-working and quite committed for the job.
PROJECT GUIDE:
………………………………………
Mr. PRASANTA.KU. BEHERA
SR. MANAGER (operation)
Emp No:100792
NTPC Ltd., Talcher(kaniha)
PROJECT CO-ORDINATOR:
…………………………….
Mr. SANJIB KUMAR,
A.G.M (RLI),
TSTPS, NTPC Limited
ACKNOWLEDGEMENT
A summer project is a golden opportunity for learning and self development. I
consider myself to be very lucky and honoured to be a part of the “NTPC
Ltd.,TSTPS,Kaniha” during my summer interval and having so many wonderful
people leading me through the completion of this project.
I specially thank and express my deep sense of gratitude to Mr. Prasanta Kumar
Behera(Sr.mngr(operation),emp no:100792 ) for his relentless guidance and
support. .It would not have been possible for me to take this project to this level
without his valuable guidance.
I would like to express my sincere gratitude to Mr. Sanjib Kumar(A.G.M,RLI) for
being there with us throughout the entire training period.
Last but not the least, We lend our extreme gratitude to the employees of NTPC
Ltd.,Kaniha for their co-operation during the training and project work who gave
us their precious time and explained all the activities carried out in the power plant.
DECLARATION
I, hereby declare that the project entitled “500 MW BOILERS” report submitted
by me is completely based on my efforts under the guidance of my guide and
mentor, Mr. Prasanta Kumar Behera (SR. Manager).
This report is submitted as a part of the partial fulfillmentof
my degree and has not been submitted to any other university
in any other form or not published at any time before.
I do hereby declare that this report will fulfill the need ofuniversity
training program I had undergone.
Date:Place:- Kaniha
Name:- Biswabijayit Jagdev
(Diploma) Electrical
CONTENTS:
1. NATIONAL THERMAL POWER CORPORATION
2. KANIHA POWER PLANT-AN ELUCITATED OVERVIEW
3. WHAT IS A BOILER?
4. COMPONENTS OF ABOILER
5. BOILER AUXILIARIES
6. AIR AND DRAFT SYSTEM
7. PRIMARY AIR FANS
8. FORCED DRAFT FANS
9. INDUCED DRAFT FANS
10. FUEL AND OIL SYSTEMS
11. BOWL MILLS
12. BALL AND RACE MILLS
13. TUBE MILLS
14. FLUE GAS SYSTEMS
15. TYPES OF SEALS
16. ELECTROSTATIC PRECIPITATOR
17. RANKINE CYCLE
18. TALCHER-K STAGE-1 BOILER
19. TALCHER-K STAGE -2 BOILER
20. TURBINE AND ITS AUXILIARIES
21. CONCLUSION
22. BIBLIOGRAPHY
NTPC Limited (formerly National Thermal Power Corporation) is the largest Indian state-owned electric
utilities company based in New Delhi, India. It is listed in Forbes Global 2000 for 2012 ranked at 337th in the world. It
is an Indian public sector company listed on the Bombay Stock Exchange in which at present the Government of India
holds 84.5% (after divestment of the stake by Indian government on 19 October 2009) of its equity. With an electric
power generating capacity of 41,184 MW, NTPC has embarked on plans to become a 128,000 MW company by 2032.
It was founded on 7 November 1975.
On 21 May 2010, NTPC was conferred Maharatna status by the Union Government of India.[4]
NTPC's core business is engineering, construction and operation of power generating plants and providing
consultancy to power utilities in India and abroad.
The total installed capacity of the company is 36,514 MW (including JVs) with 16 coal-based and seven gas-based
stations, located across the country. In addition under JVs (joint ventures), six stations are coal-based, and another
station uses naphtha/LNG as fuel. By 2017, the power generation portfolio is expected to have a diversified fuel mix
with coal-based capacity of around 27,535 MW, 3,955 MW through gas, 1,328 MW through hydro generation, about
1,400 MW from nuclear sources and around 1,000 MW from Renewable Energy Sources (RES). NTPC has adopted a
multi-pronged growth strategy which includes capacity addition through green field projects, expansion of existing
stations, joint ventures, subsidiaries and takeover of stations.NTPC has been operating its plants at high efficiency
levels. Although the company has 19% of the total national capacity it contributes 29% of total power generation due
to its focus on high efficiency. NTPC’s share at 31 Mar 2001 of the total installed capacity of the country was 24.51%
and it generated 29.68% of the power of the country in 2008–09. Every fourth home in India is lit by NTPC. As at 31
Mar 2011 NTPC's share of the country's total installed capacity is 17.18% and it generated 27.4% of the power
generation of the country in 2010–11. NTPC is lighting every third bulb in India. 170.88BU of electricity was produced
by its stations in the financial year 2005–2006. The Net Profit after Tax on 31 March 2006 was 58.202 billion. Net
profit after tax for the quarter ended 30 June 2006 was 15.528 billion, which is 18.65% more than that for the same
quarter in the previous financial year. It is listed in Forbes Global 2000, for 2011 ranked it 348th in the world.
KANIHA POWER PLANT- AN ELUCIDATED
OVERVIEW
TALCHER, KANIHA PLANT IS LOCATED IN THE KANIHA BLOCK, UNDER TALCHER SUBDIVISION IN ANGUL DISTRICT OF ORISSA.
•
•
•
•
NEAREST TOWN
NEAREST RAILWAY STATION
NEAREST AIRPORT
NEAREST PORT
-
TALCHER
TALCHER
- BHUBANESWAR
PARADIP
-
26 KMS
26 KMS
180 KMS
240 KMS
CAPACITY:
TOTAL - 3000MW (6 X 500 MW)
•
STAGE - I - 2 X 500 MW - INSTALLED
•
STAGE - II - 4 X 500 MW - INSTALLED
TOTAL LAND: 3890 ACRES.
SOURCE OF WATER:
•
BETWEEN DOWNSTREAM OF RENGALI DAM AND
•
UPSTREAM OF SAMAL BARRAGE ON RIVER
•
BRAHMANI
SOURCE OF FUEL:
•
TALCHER AND IB VALLEY COALFIELDS OF
•
MAHANADI COALFIELDS LTD
WATER REQUIREMENT
:
138 CUSEC
COAL REQUIREMENT
:
16 MILLION TONS / YEAR
APPROVED PROJECT COST
:
•
STAGE-I- Rs.2592.18 CRORES [WORLD BANK (IBRD LOAN) US $ 250.35 MILLION, FRENCH BILATERAL CREDIT FF 531.52 MILLION]
•
STAGE-II- Rs.6648.83 CRORES
TRANSMISSION LINES:
•
•
•
•
•
•
•
TALCHER - KOLAR: +500 KV, DC 2000 MW HVDC BI-POLE
TALCHER, KANIHA - RENGALI: 400 KV AC D/C (PGCIL)
TALCHER, KANIHA – ROURKELA: 400 KV AC D/C (PGCIL)
TALCHER, KANIHA - MERAMUNDALI: 400 KV AC D/C (PGCIL)
TALCHER, KANIHA – MERAMUNDALI: 220 KV AC D/C (GRIDCO)
TALCHER, KANIHA – RENGALI: 220 KV AC S/C (GRIDCO)
TALCHER, KANIHA – TTPS: 220 KV AC S/C (GRIDCO)
MILESTONES
UNITS
UNIT-I
UNITII
UNITIII
UNITIV
UNITV
UNITVI
1ST BOILER LIGHT UP
02.10.94
22.11.95
11.09.02
05.07.03
18.01.04
27.09.04
SYNCHRONISATION
12.02.95
27.03.96
04.01.03
25.10.03
13.05.04
06.02.05
COMMERCIALISATION
01.01.97
01.07.97
01.08.03
01.03.04
01.11.04
01.08.05
UNIQUE FEATURES OF TSTPS

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










ONCE THROUGH SUB CRITICAL TOWER TYPE BOILERS FOR STAGE I UNITS AND TWO PASS BHEL MAKE BOILERS FOR STG-II UNITS.
SLOW SPEED DOUBLE ENDED TUBE MILL TO MATCH FAST RESPONSE OF ONCE THROUGH BOILER OF STG-I.
NOZZLE GOVERNED TURBINE WITH SLIDING PRESSURE OPERATION FOR STG-I UNITS.
GCB AT GENERATOR TERMINAL BEFORE GT TO REDUCE NO OF STATION TRANSFORMERS.
STG-I UNITS ARE DESIGNED FOR QUICK STARTUP AND FAST LOAD RAISING.
STATE OF ART TECHNOLOGY WITH DDCMIS CONTROL FOR BOTH STG-I AND STG-II UNITS.
CENTRALISED CONTROL ROOM WITH LVS DISPLAY FOR STG-II UNITS.
TOTAL COMPUTERISED MONITORING & PLC CONTROL FOR ALL OFFSITE SYSTEMS.
INCREASING FLEXIBILITY OF OPERATION THROUGH CRT BASED DESK OPERATION.
HIGHLY EFFICIENT ELECTROSTATIC PRECIPITATOR FOR LOW STACK EMISSION.
275 MTRS HIGH CHIMNEY FOR WIDER DISPERSION OF FLUE GAS.
ZERO DISCHARGE CONCEPT WITH ASH WATER RECIRCULATION SYSTEM FOR ENVIRONMENTAL PROTECTION.
FURNACE DRAFT CONTROL BY VARIABLE FREQUENCY DRIVE FOR ID FANS TO MINIMISE AUXILIARY POWER CONSUMPTION.

VAPOUR ABSORPTION MACHINE FOR AIR CONDITIONING OF STG-II CONTROL TOWER TO AVOID USE OF FREON GAS AND ALSO TO REDUCE APC.
POWER
ALLOCATION
TO
BENEFICIARY
STATES BY
STAGE-I
BIHAR
ER
MW
BIHAR
JHARKHAND
ORISSA
WB
SIKKIM
DVC
OTHERS
TOTAL
SR
TAMILNADU
NR
UP
Rajasthan
J&K
Total
NER
Assam
WR
MP
CHATISHGARAH
MAHARASTRA
DADRA NAGAR HAVELI
DAMAN & DIU
TOTAL
35.4
5.7
31.8
9.1
2.4
0.31
15.29
100
354
57
318
91
24
3.1
152.9
1000
3.9
39
1.39
0.84
0.52
2.75
13.9
8.4
5.2
27.5
3.17
31.7
1.34
0.61
2.78
0.26
0.48
5.47
13.4
6.1
27.8
2.6
4.8
54.7
SER
3.17
31.7
0.31%
2.40%
JHARKHA
ND
15.29%
ORISSA
35.40%
9.10%
WB
SIKKIM
31.80%
5.70%
DVC
OTHERS
Generation (MU )
24000
21185
22000
23656
20000
18000
16246
16000
14000
12000
11759
10991
10000
8000
2003-04
2004-05
2005-06
2006-07
2007-08
(Upto Sep-07)
WHAT IS A BOILER?
“BOILER” means any closed vessel exceeding 22.75 liters in capacity which is used expressly for generating steam
under pressure and includes any mounting or other fitting attached to such vessel, which is wholly or partly under
pressure when steam is shut off. The term BOILER is used for a closed vessel in which water or other fluid is heated.
The fluid does not necessarily boil. The heated or vaporized fluid exits the boiler for use in various processes or
heating applications.
COMBUSTION REACTIONS

C +O2--->CO2

2C+O2

2H+O2--->H2O

S +02--->SO2
33820 KJ/Kg
--->2CO
10200 KJ/Kg
COMBUSTION EQUATIONS
AIR REQUIRED =4.31[(8/3) Carbon – 8(Hydrogen-0xygen/8)-S]
 ATMOSPHERIC AIR = N2 - 77% O2 - 23% by weight
N2 -79%
O2- 21% by volume
 EXCESS AIR FOR COMPLETE COMBUSTION- 15 TO 20%
Boiler’s efficiency depends on the 3-T LAW of COMBUSTION
1. TIME
All combustion requires sufficient Time which depends upon type of Reaction.
2. TEMPERATURE
Temperature must be more than ignition temperature.
3. TURBULENCE
Proper turbulence helps in bringing the fuel and air in intimate contact and gives them enough time to complete reaction.
COMPONENTS OF A BOILER

ECONOMISERS- Mechanical devices intended to reduce energy consumption, or to perform another useful function such as
preheating steam. It is a heat exchanger.





FORMS PART OF FEED WATER CIRCUIT
PRE HEAT BOILER FEED WATER
RECOVERY OF HEAT FROM FLUE GAS
LOCATED IN BOTTOM OF REAR PASS
NO STEAM FORMATION

BOILER DRUM- It is a reservoir of water/steam at the top end of the water tubes. The drum stores the steam generated in the water
tubes and acts as a phase-separator for the steam/water mixture. The difference in densities between hot and cold water helps in the
accumulation of the "hotter"-water/and saturated-steam into the steam-drum.



TO SEPARATE WATER FROM STEAM
TO REMOVE DISSOLVED SOLIDS
TO PROTECT WATER WALLS FROM STARVATION

ACTS AS TEMPORARY PRESSURE RESERVOIR DURING TRANSIENT LOADS

DOWNCOMERS- System of pipes carrying the downward flow of water from the boiler drum carrying it to the bottom water
header of the boiler.

WATER WALL- A wall within a boiler enclosure that is composed of numerous closely set water-tubes. These tubes may be either
bare, or covered by a mineral cement.



FORMS FURNACE ENCLOSURE
GENERATION OF STEAM
PROVIDES SEALING TO FURNACE


PRIMARY SUPER HEATER- It is a device used to convert saturated steam or wet steam into dry steam.
PLATEN SUPER HEATER- It is a device used to further rise the temperature of the dry steam to release it to the main steam to
the turbines.

FINAL SUPER HEATER- It is used to reheat the CRH supply from the HP Turbine exhaust which is then sent to IP Turbine
through HRH pass.






RAISES STEAM TO HIGHER TEMPERATURE
ARRANGED IN 3 STAGES
LTSH LOCATED ABOVE ECONOMISER
RADIANT PENDENT TYPE (DIV PANEL) ABOVE FURNACE
CONVECTIVE FINAL SUPER HEATER ABOVE FURNACE IN CONVECTIVE PATH
RE-HEATER- A device using highly superheated steam or high-temperature flue gases as a medium serving to restore superheat to
partly expanded steam; used often between high - and low-pressure turbines.
RE HEAT THE STEAM FROM HP TURBINE TO 540 DEGREES
COMPOSED OF THREE SECTIONS:

RADIANT WALL REHEATER ARRANGED IN FRONT & SIDE WATER WALLS

REAR PENDANT SECTION ARRANGED ABOVE GOOSE NECK

FRONT SECTION ARRANGED BETWEEN UPPER HEATER PLATEN & REAR WATER WALL HANGER TUBES

BURNERS- A device which combines fuel and air in proper proportions for combustion and which enables the fuel-air mixture to
burn stably to give a specified flame size and shape.




32 COAL BURNERS & 16 OIL BURNERS IN ALL IN CE TYPE BOILERS OF STAGE-II 500 MW
24 COAL BURNERS & 24 OIL GUNS IN STAGE-I ANSALDO BOILER ARRANGED ON THE FRONT
IN 500 MW BOILERS, BURNERS CAN BE TILTED +30 DEGREES TO -30 DEGREES DENPENDING ON THE REQUIREMENT
NO SUCH PROVISION IN STAGE- 1 BURNERS

OIL GUNS- The assembly of parts in a burner which provides atomized fuel oil mixture to the furnace for burning.
IGNITORS- A burner smaller than the main burner, which is ignited by a spark or other independent and stable ignition source and

which provides proven ignition energy required to immediately light off the main burner.





EACH GUN IS PROVIDED WITH AN IGNITOR
HIGH ENERGY ARC, EDDY CURRENT IGNITORS
OUTPUT VOLTAGE
2500V DC
SPARKS
4 SPARKS PER SECOND
DUTY CYCLE
15 MIN ON , 30 MIN OFF

BUCK STAYS- A structural member placed against a furnace or boiler wall to limit the motion of the wall against furnace pressure.


MECHANICAL SUPPORT BEAMS SUPPORTS BOILER ENCLOSURE
TO SAFE GUARD FURNACE GEOMETRY , EXPECIALLY FURNACE EXPLOSION /IMPLOSIONS

CONTROL CIRCULATION PUMPS- The pumps which suck water from the boiler drum and send it to the bottom header of
the boiler for recirculation.





THREE PUMPS PER BOILER (2X50%)
ASSIST IN CIRCULATING WATER THROGH WATER WALL TUBES
EACH PUMP CAPACTY
2879.4 T/HR
DIFFERENTIAL PRESSURE
1.948 KSC
SPECIFIC GRAVITY
.5993@362 DEG

BOTTOM WATER SEAL TROUGH- A water sealed trough is present under the boiler just above the ash hopper to control the
expansion of the boiler and sealing of the ash into the hopper resulting in full sealing of the boiler.
COMBUSTION
Constituents of coal
(%)
Carbon
Volatile matter
Moisture
Ash
Sulphur
36.54
21.6
10
32
0.38
WHAT ARE BOILER AUXILIARIES?
Auxiliaries of steam boiler are devices that are installed to the steam boiler, and can make it operates efficiently. These
devices should be maintained and controlled, so steam boiler can run in good condition.
BOILER AUXILIARIES

AIR & DRAFT SYSTEM

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
FUEL SYSTEM




COAL BUNKERS & FEEDERS
MILLS
SEAL AIR FAN
FLUE GAS SYSTEM




FORCED DRAFT FANS
INDUCED DRAFT FANS
PRIMARY AIR FANS
WIND BOX
SCANNER FAN
AIR PRE HEATERS
ESP
CHIMNEY
SOOT BLOWERS
 WALL, APH & LR SOOT BLOWERS
AIR & DRAFT SYSTEMS
Need of Draft Systems:
• Air needed for combustion
•
Flue gases are needed to be evacuated
•
Losses due to flow need to be overcome
Types of Draft:
•
•
•
•
Natural Draft
Forced Draft
Induced Draft
Balanced Draft
FEEDERS
FUEL & OIL SYSTEMS
Axial fan
FUEL SYSTEM
•


•

•
•
•
o
The Major components are:
Coal Preparation Equipment
Feeders
Mills
Coal Firing Equipment
BurnersVolumetric Type feeder
Chain Feeder
Belt Feeder
Table type belt Feeder
Gravimetric Feeder
BOWL MILLS
o BASE CAPACITY (T/HR) AT
HGI -55
o Total Moisture-10%
o Fineness-70% THROUGH -200
MESH
BOWL MILLS







Grinding chamber
Classifier mounted above it
Pulverization takes place in rotating bowl
Rolls rotating free on journal do the crushing
Heavy springs provide the pressure between the coal and the rolls
Rolls do not touch the grinding rings
Tramp iron and foreign material discharged.
BALL& RACE MILL (E MILL)
Model no.
7E9
8.5E10
8.5E9
10E10
10.9E11
10.9E10
10.9E8
Base capacity (T/Hr)
25
35
40
55
61
70
80
THEORY OF PRECIPITATION
Electrostatic precipitation removes particles from the exhaust gas stream of Boiler combustion process. Six activities typically take place:
 Ionization - Charging of particles
 Migration - Transporting the charged particles to the collecting surfaces
 Collection - Precipitation of the charged particles onto the collecting surfaces
 Charge Dissipation - Neutralizing the charged particles on the collecting surfaces
 Particle Dislodging - Removing the particles from the collecting surface to the hopper
Particle Removal - Conveying the particles from the hopper to a disposal point
COMPONENTS OF ESP
•
•
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•
•
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•
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•
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•
•
•
•
•
•
•
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Discharge Electrodes-Discharge electrodes emit charging current and provide voltage that generates an electrical field between the
discharge electrodes and the collecting plates. The electrical field forces dust particles in the gas stream to migrate toward the
collecting plates. The particles then precipitate onto the collecting plates. They are typically supported from the upper discharge frame
and are held in alignment between the upper and lower discharge frames. The upper discharge frame is in turn supported from the roof
of the precipitator casing. High-voltage insulators are incorporated into the support system.
Power Components-The power supply system is designed to provide voltage to the electrical field (or bus section) at the highest
possible level. The voltage must be controlled to avoid causing sustained arcing or sparking between the electrodes and the collecting
plates. Electrically, a precipitator is divided into a grid, with electrical fields in series (in the direction of the gas flow) and one or more
bus sections in parallel (cross-wise to the gas flow). When electrical fields are in series, the power supply for each field can be adjusted
to optimize operation of that field. Likewise, having more than one electrical bus section in parallel allows adjustments to compensate
for their differences, so that power input can be optimized. The power supply system has four basic components:
Automatic voltage control
Step-up transformer
High-voltage rectifier
Sensing device
Precipitator Controls
Rapping Systems-Rappers are time-controlled systems provided for removing dust from the collecting plates and the discharge
electrodes. Rapping systems are actuated by electrical, or by mechanical means. Rapping methods include
Discharge Electrode Rapping : Discharge electrodes should be kept as free as possible of accumulated particulate
Collecting Plate Rapping: Remove the bulk of the precipitated dust
Purge Air Systems-Ductwork connects the precipitator with upstream and downstream equipment. The design of the ductwork takes
into consideration the following:
Low resistance to gas flow
Gas velocity distribution
Minimal fallout of fly ash
Minimal stratification of the fly ash
Low heat loss
Structural integrity
Flue Gas Conditioning-Fly ash resistivity can be modified (generally with the intent to reduce it) by injecting one or more of the
following upstream of the precipitator:
Sulfur trioxide (SO3)
Ammonia (NH3)
Water
Sulfur Trioxide and Ammonia Conditioning Systems
In most cases, a sulfur trioxide conditioning system is sufficient to reduce fly ash resistivity to an acceptable level. The source of sulfur
trioxide can be liquid sulfur dioxide, molten elemental sulfur, or granulated sulfur. It is also possible to convert native flue gas SO2 to
SO3. The source of ammonia may be liquid anhydrous or aqueous ammonia, or solid urea.
Emitting Electrodes-It emits charged particles into space by corona discharge and then the charge gets deposited on the ash particles
resulting in their collection.
Collecting Electrodes-Collecting electrodes are designed to receive and retain the precipitated particles until they are intentionally
removed into the hopper. Collecting plates are also part of the electrical power circuit of the precipitator. These collecting plate
functions are incorporated into the precipitator design. Plate baffles shield the precipitated particles from the gas flow while smooth
surfaces provide for high operating voltage. Collecting plates are suspended from the precipitator casing and form the gas passages
within the precipitator.
High Voltage Equipment
Hoppers-Precipitator hoppers are designed to completely discharge dust load on demand. Typically, precipitator hoppers are
rectangular in cross-section with sides of at least 60-degree slope. These hoppers are insulated from the neck above the discharge
flange with the insulation covering the entire hopper area. In addition, the lower 1/4- 1/3 of the hopper wall may be heated. Discharge
diameters are generally 200-300mm. The fly ash handling system evacuates the fly ash from the hoppers, and transports the fly ash to
reprocessing or to disposal. The ash handling system are designed and operated to remove the collected fly ash from the hoppers
without causing re-entrainment into the gas flow through the precipitator. The design of the ash handling system allow for flexibility of
scheduling the hopper discharges according to the fly ash being collected in these hoppers.
Heaters- Heaters are used to evaporate the moisture present in fly ash so that efficient flow of fly ash flow would be maintained and the
pipes would not corrode under moisture conditions.
ALI
Gas Distribution Screen-For creating similar gas and dust conditions Uniformity is desired in the following parameters:
Gas velocity
Gas temperature
Dust loading

Gas distribution devices, which ensure this, consist of turning vanes in the inlet ductwork, and perforated gas distribution plates in the
inlet and/or outlet fields of the precipitator.
•
Segregating Gates
FACTORS AFFECTING ESP PERFORMANCE
• Particle Size Distribution
•
Gas Speed
• Particle Resistivity (can change with presence of sulfur, Moisture, temperature)
• ESP Voltage Levels
• Re-entrainment of Fly Ash
–
Rapping Frequency
–
Fly Ash Properties. (Cohesive Property)
•
Sparking, back corona and
•
Particle Loading
PERFORMANCE IMPROVEMENTS
• Coal Mills The setting of the coal mills and classifiers defines the coal particle size which in turn impacts the fly ash
particle size. Larger coal particles are more difficult to combust, but larger fly ash particles are easier to collect in the
precipitator. Furnace Base-load operation of the boiler is usually better for precipitator operation than swing-load
operation due to more stable operating conditions.
• Furnace: Base-load operation of the boiler is usually better for precipitator operation than swing-load operation due to
more stable operating conditions. Boiler operation at low loads may be as problematic for the precipitator as operating
the boiler at its maximum load level, due to fallout of fly ash in the ductwork, low gas temperatures, and deterioration of
the quality of the gas velocity distribution. If low load operation cannot be avoided, the installation of additional gas flow
control devices in the inlet and outlet of the precipitator may prove beneficial.
BASIC RANKINE CYCLE
T
E
ensible heat Addition in Economizer
M
P
E
R
A
T
U
Pump Work
R
E
Super Heating
Adiabatic Expansion in Turbine
L+V
Constant Pressure Heat Rejection in Condenser
ENTROPY
BOILER MANUFACTURING SPECIFICATIONS
•
DESIGN & SUPPLY– M/s. Stein Industries, France.
•
TYPE- Tower type, Once through Circulation, Direct pulverized coal fired, balanced draft furnace, single
reheat radiant, dry bottom type.
•
BOILER SPECIFICATIONS
Boiler and Boiler Auxiliaries
•
Controlled Circulation (3 CC Pumps)
•
Smaller Dia Rifle Tubes for WW
•
Bisector Air-heater
•
Two stage reheating
•
Tower Type Once Through boiler with spiral tube arrangement
BOILER & BOILER AUXILIARIES-DESCRIPTIONS
Schematic of 500MW Talcher-K Stage-1 boiler:
Two stage Reheating(RH):
Anthracite  High CV, low VM
Semi-anthracite High CV, low VM
Bituminous  Medium CV, medium VM
Semi-BituminousMedium CV, medium VM
Lignite
 Low CV, high VM, high TM
Peat
 Very low CV, high VM & TM
Once through Boiler with spiral tube arrangement:
TALCHER-K STAGE-II BOILER
TALCHER-K STAGE-II BOILER
Raw materials for design of boilers


1.
Coal from mines
2.
Ambient air
3.
Water from natural resources (river, ponds)
A 500MW steam generator consumes about 8000 tons of coal every day
It will be considered good, if it requires about 200 cubic meter of DM water in a day
It will produce about 9500 tons of Carbon di Oxide every day
COAL FOR COMBUSTION
Generating heat energy
Air for combustion
Working fluid for steam generation,
STEAM GENERATOR IS A COMPLEX INTEGRATION OF
THE FOLLOWING ACCESSORIES :ECONOMISER
BOILER DRUM
DOWN COMERS
CCW PUMPS
BOTTOM RING HEADER
WATER WALLS
LTSH
DIV PANEL
PLATEN SH
REHEATER
BURNER
APHs
Circulation in Boiler
The steam generator has to produce steam at highest purity, and at high pressure and temperature required for the turbine. Water must
flow through the heat absorption surface of the boiler in order that it be evaporated into steam Natural circulation is the ability of
water to circulate continuously, with gravity and changes in temperature being the only driving force known as "thermal head“.
The ratio of the weight of water to the weight of steam in the mixture leaving the heat absorption surfaces is called Circulation Ratio.
Cold feed water is introduced into the steam drum where, because the density of the cold water is greater, it descends in the 'down
comer' towards the lower bottom ring header, displacing the warmer water up into the front tubes.
Continued heating creates steam bubbles in the front tubes, which are naturally separated from the hot water in the steam drum, and
are taken off.
Forced Circulation
However, when the pressure in the water-tube boiler is increased, the difference between the densities of the water and saturated steam
falls, consequently less circulation occurs. To keep the same level of steam output at higher design pressures, the distance between the
Bottom ring header and the steam drum must be increased, or some means of forced circulation must be introduced.
Therefore natural circulation is limited to boiler with drum operating pressure around 175 Kg/cm2.
Water Walls
•
•
•
•
HEATING AND EVAPORATING THE FEED WATER SUPPLIED TO THE BOILER FROM THE ECONOMISERS.
THESE ARE VERTICAL TUBES CONNECTED AT THE TOP AND BOTTOM TO THE HEADERS.
THESE TUBES RECEIVE WATER FROM THE BOILER DRUM BY MEANS OF DOWNCOMERS CONNECTED BETWEEN DRUM AND
WATER WALLS LOWER HEADER.
APPROXIMATELY 50% OF THE HEAT RELEASED BY THE COMBUSTION OF THE FUEL IN THE FURNACE IS ABSORBED BY THE
WATER WALLS.
Economizer




Boiler Economizer are feed-water heaters in which the heat from waste gases is recovered to raise the temperature of feed-water
supplied to the boiler.
The economizer preheats the feed water by utilizing the residual heat of the flue gas.
It reduces the exhaust gas temperature and saves the fuel.
Modern power plants use steel-tube-type economizers.
Design Configuration: divided into several sections : 0.6 – 0.8 m gap
CONCLUSION
For any organization there must be a proper and systematic approach towards the daily
movement of its trade and improving the efficiency of the same plays the key role in
making of an organization truly successful.
So when we consider a boiler,the most important aspect that one learns is the proper
working of different parts of the boiler as well as the boiler auxiliaries that are present in
order to derive maximum output from the power plant in a reasonably quick time.
When we got a chance to be a part of the TSTPS, our group was eager to work on such a
project which would actually help the power plant grow and achieve greater heights in
outturn capacities each new month. So we undertook this project so that we would learn
from it and side by side observe the working of the boiler and the boiler auxiliaries.
After spending some days at the power plant and realizing the great potential that is
present in the power plant, our next stop was innovation, which led us to the creation of
this project emphasizing the organizational approach to Boiler and its auxiliaries in a nonconventional manner.
BIBLIOGRAPHY
 www.google.co.in
 www.wikipedia.org
 www.ntpc.co.in
 www.yahoo.com
 www.ntpccareer.net
 economicstimes.indiatimes.net