Absolute combustion oxygen starvation

If we do not ensure that we operate some extra air to put us on the good side of the point of absolute combustion, then we run the risk of getting into oxygen starvation on the wrong side or bad side of the point of absolute combustion. 

Automatic operation linked to process outlet temperature while on the bad side of absolute combustion is potentially hazardous because the heater outlet temperature will drop as a result of the reduced heating efficiency of the fuel. The automatic control will then call for more fuel, which, in turn, produces more oxygen starvation. 

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