Question: A single-pressure waste heat recovery boiler is being considered in a combined-cycle system design. The boiler is expected to provide steam at 1250 psia and 950?F at an inlet water temperature of 274?F. Calculate the steam flow rate and stack gas temperature for the following conditions:
Exhaust gas flow rate 1.68 × 106 lb/h Exhaust gas temperature 960?F Supplementary heat addition rate 26.57 × 106 Btu/h at superheater Conduct an analysis to comment on the acceptability of the value of the stack gas temperature with respect to longevity of the exhaust stack.