A boiler generates superheated steam having temperature 270 C and pressure 13 bar. The specific heat of the superheated steam 2.1 kJ/kg-K. The temperature of the feed water is 32 C. The evaporative capacity of the boiler is 8 kg of steam per kg of fuel. The calorific value of the coal is 26000 kJ/kg.

A boiler generates superheated steam having temperature 270 C and pres

1.	A boiler generates superheated steam having temperature 270 C and pressure 13 bar. The specific heat of the superheated steam 2.1 kJ/kg-K. The temperature of the feed water is 32 C. The evaporative capacity of the boiler is 8 kg of steam per kg of fuel. The calorific value of the coal is 26000 kJ/kg.
A.	86.65%
B.	70.32%
C.	65.87%
D.	90.80%
Answer» B. 70.32%

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