NTPC ,sipat voccational training

NTPC , SIPAT
PRESENTATION

1. A PRESENTATION ON THERMAL POWER PLANT PRESENTED BY : BHUMIT SOLANKI (3023713044) 4 TH SEM

2. INTRODUCTION NTPC sipat has total installed capacity : 2980 MW Stage 1 = 3 X 660 MW Stage 2 = 2 X 500 MW   Stage 2 is based on "Super Critical Boiler Technology "

3. PRODUCITON INPUTS COAL SOURCE > Dipika Mines of South Eastern Coalfields Limited WATER SOURCE > Hasdeo barrage

4. What is “supercritical” ? “Supercritical” is the thermodynamic state where there is no clear distinction between the Water and Steam phase in the Ranking Cycle. Water reaches to steam state at a critical pressure above 22.1 MPa at 374 ° C. This "critical point" is at the apex of the saturation line on T-s coordinates . Above this pressure, the physical properties (density, compressibility, and Viscosity) change continuously from those of a liquid to those of a vapor.

5. Benefits of supercritical units Higher unit cycle efficiency (40 - 42%). Lower heat rate and electricity generation cost is lower. Lower water losses because no continuous blow down. Reduced auxiliary power consumption. Environmental Benefits Reduce carbon dioxide (CO2) emissions and provides carbon credit within the Rankine cycle.

6. LAYOUT OF THERMAL POWER PLANT

7. MAIN AND AUXILIARY EQUIPMENTS Coal handling plant Pulverizing plant Draft fans Boiler Ash handling plant Turbine Condenser Cooling towers and ponds Feed water heater Economizer Superheater and Reheater Air preheater

8. WORKING OF THERMAL POWER PLANT TURBINE GENERATOR HIGH TENSION WIRE

9. Train (coal) Track hopper Conveyer belt M ill Conveyer belt Pulverisation process Coal Coal Coal small piece of coal small piece of coal powderEd coal boiler steam Turbine Generator Electricity Tiscon pipe with basalt cutters Ash dyke Water dyke Condensation process Cooling tower Storage tank Demineralisation process steam Water Water Water Water Water Water ash + hot water ash + hot water Ventilator turbine dry ash dry ash Wind pipes Chimney Atmosphere dry ash dry ash Shaft

10. 1. COAL HANDLING PLANT A thermal power plant burns enormous amounts of coal. A 200MW plant may require around 2000 tons of coal daily The function of coal handling plant is automatic feeding of coal to the boiler furnace.

11. 2. 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: Contact mill Ball mill Impact mill

12. 3. DRAFT FANS The circulation of air is caused by a difference in pressure, known as Draft. Draft 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 – Natural draft Mechanical draft

13. 4.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- Fire tube boiler Water tube boiler

14. 5.Ash handling plant Wherever coal is burned it is necessary to have an efficient ash handling system, especially in a coal-fired power station environment where large quantities of pulverized fuel ash (PFA) are created The various systems involved in the ash handling system are: Bottom ash handling system Fly ash handling system (both wet & dry) Slurry handling system from slurry pump house to ash dyke Ash water system Ash water recirculation system Basically, two types of ash are generated: Fly ash (approx 80%) Bottom ash (approx 20%)

15. Ash collected in hoppers is grinded by grinders and mixed with water and then sent to ash slurry house by using jet pumps. Where it is collected in ASH PIT, from where it is pumped to ASH POND. Here there is also an auxiliary pump which is used for FLUSHING OFF blockages.

16. 6. STEAM TURBINE A steam turbine converts heat 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

17. 7. CONDENSER Steam after rotating steam turbine comes to condenser. Condenser refers here to the shell and tube heat exchanger (or surface condenser) installed at the outlet of every steam turbine in Thermal power stations of utility companies generally. These condensers are heat exchangers which convert steam from its gaseous to its liquid state, also known as phase transition. The purpose is to condense the outlet (or exhaust) steam from steam turbine to obtain maximum efficiency and also to get the condensed steam in the form of pure water, otherwise known as condensate, back to steam generator or (boiler) as boiler feed water.

18. CONDENSER

19. 8. 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

20. 9. ELECTROSTATIC PRECIPITATOR The exhaust gases contain large amount of smoke and dust, which are being emitted into atmosphere. This possess a real threat to the mankind as a health hazards. Hence it has become necessary to free the exhaust gases from smoke and dust. The Electrostatic precipitator utilizes electrostatic forces to separate the dust particle form the gas to be cleaned .

21. 10. 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

22. 11. 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. 12. SUPERHEATERS   Superheater is a component of a steam-generating unit in which steam, after it has left the boiler drum, is heated above its saturation temperature. The super heater may consist of one or more stages of tube banks arranged to effectively transfer heat from the products of combustion. Super heaters are classified as convection , radiant or combination of these.

24. 13. GENERATOR The Synchronous Generator is used to Generate power by connecting the shaft of the Turbine to the shaft of the generator which cuts the magnetic flux producing Emf . The Generated Voltage will generally 11KV to 20 KV max. The Generated Voltage is stepped up by connecting Step up transformer and is transmitted and is also used for Auxiliary purposes .

25. CONCLUSION Super critical power plants are the efficient plants to produce greater out put although it has some drawbacks……

26. THANK YOU