A boiler produces 4000 kg of dry and saturated steam in 6 hours. In the same time the mass of coal consumed is 300 kg of coal. The mean pressure of steam generated is 11 bar. The temperature of the feed water is 35°C. Determine the boiler efficiency if the calorific value of the fuel is 30000 kJ/kg.

A boiler produces 4000 kg of dry and saturated steam in 6 hours. In t

1.	A boiler produces 4000 kg of dry and saturated steam in 6 hours. In the same time the mass of coal consumed is 300 kg of coal. The mean pressure of steam generated is 11 bar. The temperature of the feed water is 35°C. Determine the boiler efficiency if the calorific value of the fuel is 30000 kJ/kg.
A.	85.64%
B.	75.65%
C.	95.65%
D.	87.78%
Answer» E.

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