Parts of a Steam Power Plant –
Steam Power Plant is used to generate electricity with the help of steam. The major parts or components of a steam power plant include the following –
2. Super Heater
4. Air Preheater
6. Steam Turbine
8. Cooling Tower
10. Pumps of Circulating Water
These are the major components of a steam power plant and are described below with their use –
1. Boiler –
A Boiler is a device sued to produce steam by utilizing the heat of combustion. It is a closed vessel in which the heat produced due to combustion of fuel is used to heat the incoming water for producing steam at required pressure and temperature.
2. Super Heater –
A Super Heater is used to heat the saturated steam coming out of the boiler above saturation temperature with little loss in pressure. Here the moisture is totally removed. With super – heating, the cycle efficiency rises and avoids too much condensation in the last stages of turbine.
3. Reheater –
In reheater, the steam is extracted from a suitable point from the turbine and is reheated utilizing the waste heat available from the flue gases of the boiler. The reheating results in the increase of dryness fraction of steam passing through the lower stages of turbine. Reheating reduces the specific steam consumption, the size of the boiler and auxiliaries for the given output.
4. Air Preheater –
It is one of the accessories and with the economizer. The flue gases passing out of the economizer is also at a higher temperature than ambient temperature. Therefore, the gases passing through the economizer is allowed to pass through preheater. The air after preheating is supplied to the combustion chamber. The high – pressure air always results in better combustion.
5. Economizer –
In an economizer, the waste heat of the flue gases is utilized for heating the feed water. The major heat loss in a steam boiler is heat carried away by the flue gases. Using the economizer, fuel is economized and consequently stem rate is increased.
6. Steam turbine –
Turbine is a device in which kinetic energy of the working fluid is utilized for producing the mechanical energy. Turbine is defined by Neilson as a machine in which a rotary motion is obtained by the gradual change of momentum of fluid. The high velocity steam coming out of nozzle expands in the turbine blades, making it to rotate thus producing mechanical power.
7. Condenser –
A Condenser is used to condensate the steam coming out of a turbine. Here the energy of steam in the form of latent heat is taken up by the cooling water. The steam after giving latent heat, changes its phase from vapour to liquid and leaves the condenser as condensate. The temperature of cooling water as exit is more compared to temperature at inlet.
8. Cooling Tower –
Cooling tower is a device in which the cooling water coming out of condenser is cooled. In this, the atmospheric air and the water is mixed, due to which, the heat of the water is taken up by the air and the water gets cooled.
9. Generator –
A Generator is a device which converts the mechanical energy obtained from the turbine into electrical energy.
10. Pumps –
Pumps are employed to circulate the water from a reservoir or any river to the desired location. It lifts the water to the desired height.
The above mentioned are the major components of a steam power plant.