Recent questions tagged thermal-power-plant

Description : What type of cooling is provided for Generator in power plant?

Last Answer : Hydrogen gas cooling is employed for large size generators because of better heat carrying ability of the hydrogen. Hydrogen cooling is provided for rotors and core of the generator. Water cooling is provided for the stator of the alternator.

Description : What are different types of circuit breakers employed in thermal power plant?

Last Answer : For low voltage operation 415/220V vacuum circuit breakers or air break circuit breakers are employed. For voltage ratings about 6.6kV and beyond SF6 circuit breakers are employed.

Description : How Generator Transformer is cooled in Thermal Power Plant?

Last Answer : MVA power rating of the Generator Transformer will be equal to the alternator. Hence lot of heat will be generated while generator transformer is under operation. Oil Forced Air Forced (OFAF) type of cooling is employed for generator transformer

Description : What are the different Generator Protections employed in Thermal Power Plants?

Last Answer : Faults in the windings, Over load protection, Over heating of windings or bearings, Over speed protection, Loss of Excitation protection, Motoring operation protection, Inadvertent energisation ... , out of step operation protection, sub-synchronous oscillations protection and earth fault protection

Description : What are the major electric systems in Thermal Power Plant?

Last Answer : Major electrical equipment in thermal power plant are Turbine Generator Exciter System Generator Protection System Generator Transformer HT/LT switch gear Electrical Switch-yard

Description : On what factors efficiency (thermal) of the steam plant depends?

Last Answer : Efficiency of the thermal plant depends on three factors, they are pressure of steam entering the turbine temperature of the steam entering the turbine pressure in the condenser Thermal efficiency ... as low as possible. Thermal efficiency also increases by reheating the steam between turbine stages

Description : Why the Thermal efficiency of the steam power plant is quite low?

Last Answer : In Steam power station, more than 50% of the total heat of combustion is lost as heat rejected to the condenser and the loss is unavoidable as the heat energy cannot be converted in to mechanical ... lowest temperature. This is the reason that the thermal efficiency of the power plant is quite low.

Description : What is the overall efficiency of the Thermal Power Plant or Steam Power Plant?

Last Answer : Overall efficiency of the system is defined as the ratio of heat equivalent of electrical output to the heat of combustion. Generally Overall efficiency of the steam plant will always be ... by multiplying the thermal efficiency of the plant with efficiency of the generator (electrical efficiency)

Description : What is the Thermal efficiency of steam power plant?

Last Answer : Thermal efficiency of steam power plant is defined as the ratio of heat equivalent of mechanical energy transmitted to the turbine shaft to the heat of combustion. Generally Thermal efficiency of the steam power plant will be in the range of 30-35%

Description : Steam power plant works on which cycle?

Last Answer : Steam power plant works on the principle of Rankine Cycle

Description : What are the main circuits in the Thermal Power Plant?

Last Answer : Thermal Power plant consists of four main circuits, they are: Feed water and steam flow circuit Coal and ash circuit Air and gas circuit Cooling water circuit

Description : Why are feed water heaters are used?

Last Answer : Regenerative Feedwater heaters are employed in steam power plants to improve the cycle efficiency. Also it increases the steam flow rate and reduces the steam flow to the condenser. They raise the temperature of the feed water before it enters the economizer

Description : Why cooling towers require in the Steam power plant ?

Last Answer : Cooling towers cool the warm water discharged from the condenser and feed the cooled water back to the condenser. There are two types of cooling methods provided in the cooling towers, they can be either ... finned tubes over which cooling air is passed. Heat is rejected to air as water is cooled

Description : What is the purpose of deaerator in steam power plant?

Last Answer : The presence of dissolved gases like oxygen and carbon dioxide in water makes the water corrosive, as they react with metal and forms iron oxide. The solubility of the gases in the water ... deaerator by heating the feed water to saturation temperature through the bled steam from the turbine.

Description : Why Thermal Power Plants are always situated by the side of rivers or lakes?

Last Answer : Thermal Power Plants are situated close to the rivers or lakes because to meet the large quantity of the water requirement. Water is required in the steam power plants steam in the boiler for cooling purposes such as in condensers as carrying medium such as in disposal of ash for drinking purpose

Description : Write about classification of draught?

Last Answer : Draught is classified as 1. Natural draught 2. Artificial draught

Description : Define draught, what is the use of draught in thermal power plants?

Last Answer : Draught is defined as a small pressure difference required between the fuel bed (furnace) and outside air to maintain constant flow of air and to discharge the gases through chimney to the atmosphere. ... combustion products through the system. · To remove burnt products from the system

Description : What is the working principle of Cooling Towers?

Last Answer : The hot water is sprayed from the top of the tower, while the air is made to flow from the bottom of the tower to the top. This air cools the hot water in the cooling tower. Air vaporises ... and leaves at the top of the tower and cooled water leaves at the bottom and recirculated to the condenser.

Description : What are different types of Steam boilers used in Thermal Power Plants?

Last Answer : Different type of boiler used in thermal power plants are: Fire tube boiler Water tube boiler Natural Circulation boiler Forced Circulation boiler Once through boiler

Description : List the types of super heaters:

Last Answer : 1. Radiant super heater- absorb heat by radiation 2. Convention super heater-absorb heat via a fluid 3. Separately fixed super heaters- it is totally separated from the boiler

Description : What is meant by cooling Towers?

Last Answer : It is a tower or building like device in which atmospheric air circulates in direct or indirect contact with warmer water and water is thereby cooled. Cooling towers may either use the evaporation of water to remove process heat and cool the working fluid

Description : What consists of cooling water circuit and coal & ash circuit in steam power plant?

Last Answer : The cooling water circuit consists of a pump, condenser and cooling tower. The coal and ash circuit consists of coal delivery, preparation of coal, handling of coal to the boiler furnace, ash handling and ash storage.

Description : What consists of feed water and steam flow circuit in steam power?

Last Answer : The feed water and steam flow circuit consists of feed pump, economizer boiler drum super heater, turbine and condenser.

Description : What consists of air and flue gas circuit?

Last Answer : Air and flue gas circuit consists of forced draught fan, air-pre-heater, boiler, furnace, super heater, economizer, dust collector, induced draught fan and chimney.

Description : Name the four major circuits in steam power plant.

Last Answer : • Coal and ash circuit • Air and flue gas circuit • Feed water and steam circuit • Cooling water circuit

Description : What is the function of Air preheater?

Last Answer : Air pre heater is used to transfer heat from the flue gases to the air before it passes into the furnace for combustion thereby increasing the thermal efficiency of the process.

Description : What is an Economizer?

Last Answer : An economizer is a mechanical device which is used as a heat exchanger by preheating water by recovering residual heat from the flue gases in thermal power plant.

Description : What is superheater?

Last Answer : A superheater is a device used to convert saturated steam or wet steam into dry steam

Description : Why the preparation of coal is necessary?

Last Answer : The coal from coal nines cannot be directly fed into the furnace. Proper preparation of coal should be done before feeding the coal to the furnace. In the coal preparation, the coal passes through the different equipments like 1.Crushers 2. Sizers 3. Driers and Magnetic Separators.

Description : Explain the working of thermal power plant.

Last Answer : It uses coal as the primary fuel to boil the water available to superheated steam for driving the steam turbine. The steam turbine is then mechanically coupled to an alternator rotor, the rotation of which results in the generation of electric power.

Description : List the factors to be considered while choosing a site for steam power station:

Last Answer : 1.Supply of fuel 2.Availability of water 3.Transportation facilities 4.Cost and type of land 5.Nearness to load centres 6.Distance from populated area