State necessity of super heater in steam boilers. State advantages of economizer.

State necessity of super heater in steam boilers. State advantages of economizer. 
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1 Answer

Answer :

Necessity of super heater in steam boilers:

1. The efficiency of the boiler is increase with the use of superheated steam.

2. It eliminates the erosion of the turbine blades.

3. It reduces specific steam consumption of engine and turbine.

Advantages of economiser:

1. Saving of fuel.

2. Dissolved gases as air and CO2 are removed by preheating the feed water; so reducing corrosion and pitting.

3. There will be less temp. strain in the boiler plates as the feed water enters the boiler at a higher temp.

4. Circulation of the water is very well maintained as quick evaporation is possible because of hot feed water.

5. This unit improves the overall efficiency of the boiler by reducing the fuel consumption. 
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