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SUMMER TRAINING NTPC DADRI

ABOUT NTPCNTPC is the largest power generating company in india, was set up in 1975 to accelerate power development in the country.

NTPC has installed capacity of (29,394MW).

NTPC has 15 coal based power stations (23,395MW).

NTPC has 7 gas based power stations (3,955MW).

NTPC has 4 power stations in joint ventures (1,794MW).

Today NTPC contributes more than 3/5th of the total power generation in india.

In 1997 , Government of india granted NTPC status of Navratna.

ABOUT NTPC, DADRIIt has energy generating capacity by -coal based thermal plant is 1820MW . -gas based thermal plant is 817 MW.

It has 6 units of coal based thermal plant . -4 units are of 210 MW & 2 units are of 490 MW capacity.

It has 6 units of gas based thermal plant . -4 units are of 130 MW & 2 units are of 154 MW Grand Total capacity is2637 MW.

COAL SOURCE - Piparwara mines , Jharkhand

WATER SOURCE - Upper Ganga Canal, Mat Branch

GAS SOURCE - HBJ Pipe line

SOURCESOPERATION OF THERMALPOWER PLANT

OPERATION MECHANISM

The coal is brought and crushed to powder. This is feed to boiler for producing heat . In Boiler the water is converted to steam.In super heater the moisture content is removed from the steam and that steam is called super heated steam.The superheated steam rotates the shaft of the High pressure turbine.The exhausted steam is sent to preheater and the steam then rotates the intermediate pressure (IP) turbine. The steam from the IP Turbine is then feed to low pressure turbine.The turbine shaft is connected to the Generator, which produceselectric Power.The power generated is then transmitted .MAIN AND AUXILIARY EQUIPMENTCoal handling plantPulverizing plantBoilerSuperheater TurbineGeneratorCondenserCooling tower and poundsFeed water heaterEconomizer and ReheaterAir preheaterSwitchyardAsh handling plant

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 following are the process of plant-:Unloading process Feeding process Screening process Crushing process Stacking process Reclaiming process Bunkering process

A boiler or steam generator is a closed vessel to 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.BOILER

SUPER HEATERA device which moves last traces of moisture.

It helps in reduction in requirement of steam quantity.

Steam being dry reduces the mechanical resistance of turbine.

No corrosion at the Turbine blades.

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 represents the heat energy converted into kinetic energy.

These are of two types :- Impulse turbine Reaction turbine GENERATOR

The Synchronus Generator is used to generate power by connecting the shaft of the Turbine to the shaft of the generator which create the magnetic flux producing Emf.

The generated voltage will generally 33 KV to 11 KV max.

the generated Voltage is stepped up by connecting Step up transformer and is also used for auxilliary purpose.CONDENSER

Which condenses the steam at the exhaust of turbine.

It creates a very low pressure at the exhaust of turbine, this helps in converting heat energy of steam into mechanical energy in the prime mover.

The condensed steam can be used as feed water to the boiler. COOLING TOWER

Remove heat from the water discharged from the condenser so that the water can be discharged to the river or re circulated and reused.

Air can be circulated in the cooling towers through natural draft and mechanical draft. SWITCHYARDA switchyard is a part of an electrical generation, transmission system.

Switchyard transform voltage from high to low or the reverse, or perform any of several other important functions

EQUIPMENTS IN SWITCHYARDOUTDOOR EQUIPMENTS BUS BARLIGHTENING ARRESTERBREAKERCAPACITIVE VOLTAGE TRANSFORMEREARTHING RODCURRENT TRANSFORMERPOTENTIAL TRANSFORMER

INDOOR EQUIPMENTSRELAYSCONTROL PANNELCIRCUIT BREAKERSASH HANDLING PLANTThe 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

UTILISATION OF SECONDARY RAW MATERIAL (ASH)Construction of embankments and fills

Construction of road in sub-base

Manufacture of cement

Manufacture of bricks/blocks

Filling as flowable fill material

Agriculture as soil amendment/source of essential plant nutrientsADVANTAGESThe fuel used is quite cheap.

Less initial cost as compared to other generating plants.

It can be installed at any place irrespective of the existence of coal.

The coal can be easily transported to the site

It require less space as compared to Hydro power plants.

Cost of generation is less than that of diesel power plants.DISADVANTAGESIt pollutes the atmosphere due to production of large amount of smoke and fumes.

It is costlier in running cost as compared to Hydro electric plants.

Maintenance cost is more.