Question

How flue gas is made use of in steam power plant?

(a) To maintain the constant pressure inside boiler

(b) To heat the water in the tubes of boiler

(c) To increase or decrease the pressure inside the boiler

(d) To remove all unnecessary chemical constituents

This question was posed to me during an online interview.

Question is taken from Cooling Water System, Air & Fuel Gas System in division Steam Power Plant of Energy Engineering

Answer 1

Correct answer is (b) To heat the water in the tubes of boiler

For explanation I would say: The flue gases are circulated in the furnace to heat the water in tubes. First it is passed over economizer and then to the pre-heater. And then finally after making maximum utilization of the flue gas they are exhausted through chimneys.