Mole balances with heat exchange

Figure ES 7.2 PER with heat exchange, 1. The mole balance ...

A fuel gas containing 95 mole% methane and the balance ethane is burned completely with 25% excess air. The stack gas leaves the furnace at 900 C and is cooled to 450°C in a waste heat boiler, a heat exchanger in which heat lost by cooling gases is used to produce steam from liquid water for heating, power generation, or process applications. 

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