This presentations contains the basic layout of a thermal power palnt along with the components.Coal and it's types.Future of thermal power plant in India.
3. CONTENTS:
1. Introduction
2. Power plant layout
3. Main and Auxiliary Equipment
4. Classification of coal
5. Efficiency of a Thermal power plant
6. India’s biggest Thermal power plants
7. Advantages and Disadvantages
8. Future of Thermal power plant in India
4. Thermal power plant
A Thermal power plant is a power plant in which heat energy is converted to
Electric power. In most of the places in the world the turbine is steam-driven.
Water is heated, turns into steam and spins a steam turbine which drives an
Electrical generator.
A Thermal Power Plant converts the heat energy of coal into
electrical energy. Coal is burnt in a boiler which converts
water into steam. The expansion of steam in turbine produces
mechanical power which drives the alternator coupled to the
Turbine.
Thermal Power Plants contribute maximum to the
generation of Power for any country .
Thermal Power Plants constitute 60% of the total installed captive and non
captive power generation in India . In thermal generating stations coal,
oil, natural gas etc. are employed as primary sources of energy.
6. 1. Cooling tower. 2. Cooling water pump. 3. Transmission line (3-phase). 4. Unit transformer (3-phase). 5. Electric generator
(3-phase). 6. Low pressure turbine. 7. Condensate extraction pump. 8. Condenser. 9. Intermediate pressure turbine. 10. Steam
governor valve. 11. High pressure turbine. 12. Deaerator. 13. Feed heater. 14. Coal conveyor. 15. Coal hopper. 16. Pulverised
fuel mill. 17. Boiler drum. 18. Ash hopper. 19. Superheater. 20. Forced draught fan. 21. Reheater. 22. Air intake. 23. Economiser.
24. Air preheater. 25. Precipitator. 26. Induced draught fan. 27. Chimney stack. 28. Feed pump.
Typical Layout of Thermal power plant with all the Equipments
7. MAIN AND AUXILIARY
EQUIPMENTS
1. Coal handling plant
2. Pulverizing plant
3. Draught fans
4. Boiler
5. Ash handling plant
6. Turbine
7. Condenser
8. Cooling towers and ponds
9. Feedwater heater
10. Economiser
11. Superheater and Reheater
12. Air preheater
8. Coal Handling Plant
•The function of coal handling plant is automatic feeding of coal to the
boiler furnace.
•A thermal power plant burns enormous amounts of coal.
•A 200MW plant may require around 2000 tons of coal daily
9. PULVERISING PLANT
In modern thermal power plant , coal is
pulverised i.e. ground to dust like size and
carried to the furnace in a stream of hot air.
Pulverising is a means of exposing a large
surface area to the action of oxygen and
consequently helping combustion.
Pulverising mills are further classified as:
1.Contact mill
2.Ball mill
3.Impact mill
10. DRAUGHT SYSTEM
• The circulation of air is
caused by a difference in
pressure, known as Draught.
• Draught is a differential
pressure b/w atmosphere
and inside the boiler.
• It is necessary to cause the
flow of gases through boiler
setting
• It may be –
1. Natural draught
2. Artificial draught
12. BOILER
• A boiler or steam generator is a closed vessel in which water
under pressure, is converted into steam.
• It is one of the major components of a thermal power plant
• Always designed to absorb maximum amount of heat released
in
the process of combustion
Boilers are of two types-
1.Fire tube boiler
2.Water tube boiler
13. SUPERHEATER AND REHEATER
Superheater :
A Superheater is a device used to convert saturated steam or wet steam into superheated
steam or dry steam. Superheaters are used in steam turbines for electricity generation, steam
engines, and in processes such as steam reforming.
14. Reheater :
Power station furnaces may have a reheater section containing tubes heated by hot flue gases
outside the tubes. Exhaust steam from the high-pressure turbine is passed through these
heated tubes to collect more energy before driving the intermediate and then low-pressure
turbines.
15. STEAM TURBINE
A steam turbine converts thermal energy of steam into mechanical
energy and drives the generator. It uses the principle that steam
when issuing from a small opening attains a high velocity. This
velocity attained during expansion depends on the initial and
final heat content of the steam. This difference b/w initial and
final heat content repesents the heat energy converted into
kinetic energy.
These are of two types :-
Impulse turbine
Reaction turbine
16. ASH HANDLING PLANT
The percentage of ash in coal varies from 5% in good quality coal to
about 40% in poor quality coal
Power plants generally use poor quality of coal , thus amount of ash
produced by it is pretty large
A modern 2000MW plant produces about 5000 tons of ash daily
The stations use some conveyor arrangement to carry ash to dump
sites directly or for carrying and loading it to trucks and wagons which
transport it to the site of disposal.
17. CONDENSER
A surface condenser is a commonly used term for a water-cooled shell
and tube heat exchanger installed on the exhaust steam from a steam
turbine in thermal power stations. These condensers are heat exchangers
which convert steam from its gaseous to its liquid state at a pressure below
atmospheric pressure.
18. COOLING TOWERS AND PONDS
● A condenser needs huge quantity of water to condense the steam .
● Typically a 2000MW plant needs about 1500MGallon of water.
● Most plants use a closed cooling system where warm water coming from
condenser is cooled and reused
● Small plants use spray ponds and medium and large plants use cooling
towers.
● Cooling tower is a steel or concrete hyperbolic structure having a reservoir at the
base for storage of cooled water
● Height of the cooling tower may be 150 m or so and diameter at the base is
150 m
19. FEEDWATER HEATER
A feedwater heater is a power plant component used to pre-heat water delivered to a
steam generating boiler. Preheating the feedwater reduces the irreversibility involved in
steam generation and therefore improves the thermodynamic efficiency of the system.
20. ECONOMISER
Flue gases coming out of the boiler carry lot of heat. An
economiser extracts a part of this heat from flue gases
and uses it for heating feed water. This use of
economiser results in saving coal consumption and
higher boiler efficiency.
21. AIR PREHEATER
After flue gases leave economiser, some further heat
can be extracted from them and used to heat
incoming heat. Cooling of flue gases by 20 degree
centigrade increases the plant efficiency by 1%.
Air preheaters may be of three types
Plate type
Tubular type
Regenerative type
23. Efficiency of a Thermal power Plant
The energy efficiency of a conventional thermal power station, considered
salable energy produced as a percent of the heating value of the fuel
consumed, is typically 33% to 48%. As with all heat engines, their efficiency
is limited, and governed by the laws of thermodynamics.
24. India’s Biggest Thermal power plants
1.Vindhyachal Thermal Power Station, Madhya Pradesh
Vindhyachal Thermal Power Station in the Singrauli district of Madhya Pradesh, with an
installed capacity of 4,760MW, is currently the biggest thermal power plant in India. It is a
coal-based power plant owned and operated by NTPC.
25. 2.Mundra Thermal Power Station
The 4,620MW Mundra Thermal Power Station located in the Kutch district of
Gujarat is currently the second biggest operating thermal power plant in India. It is a
coal-fired power plant owned and operated by Adani Power.
26. 3.Mundra Ultra Mega Power Plant (UMPP)
The 4,000MW Mundra Ultra Mega Power Plant (UMPP), also located in the Kutch district of
Gujarat, ranks as the third largest thermal power plant in India. It is a coal-fired power
plant owned and operated by Coastal Gujarat Power Limited (CGPL), a subsidiary of Tata
Power.
27. Advantages:
●Very Cheap
● Less Space Compared to Hydro Power Station
● Capital Cost Rs. 3 – 4 Cr /MW
● Located at Load centers
● Quick response to Load Variations
Disadvantages:
● High Maintenance
● High Pollution
● Ash Disposal
● Long time- (Erection & Installation)
● High Operating Cost
28. Futureof Thermal power plant in India
CEA(Central Electricity Authority) says that around 50,000 MW of coal power
plants is under construction which would be most likely beneficial for the
period 2017–2022 and fulfill the demand in the 5 year period 2022–27.
The report also says that the share of renewable energy would be around 20%
in 2021–22 and 24.6% in 2026–27.
Older units are most likely to be replaced by super-critical units.
The target for renewable energy addition by 2022 has been revised to
175GW(1,75,000MW) and that’s a huge task and would require huge investments.
KOLKATA: Coal-fired power generation is expected to grow 4.05 per cent during
2017-18, suggests Central Electricity Authority (CEA) in its latest
estimates. Hydel on the other hand is expected to grow 5.52 per cent, while
nuclear will grow only about 2.43 per cent during the same year.
I think the future of coal based power plants would not be good as we
progress and invest more and more in clean energy technologies.
29. Thank You
Prabakaran Sir for guiding us patiently.
Soham Sir for your timely inputs and support whenever we needed.
