Question 174Steam Plants - Assistant Engineer

The correct answer is B) Operating with a bypassed economizer. When the economizer is bypassed, less heat is extracted from the flue gases before they enter the superheater. This results in higher superheater inlet temperatures, leading to higher superheater outlet steam temperatures. The other options are incorrect because: A) Insufficient excess air would reduce heat transfer, leading to lower superheater outlet temperatures. C) Excessive heat transfer in the control desuperheater would actually lower the superheater outlet temperature. D) High water level in the steam drum would not directly affect the superheater outlet temperature.