Flammability of low-Btu gases

Every engineer whose responsibilities include furnaces, fuels, incinerators or processes involving offgases is occasionally confronted with an offgas or a waste stream that needs to be incinerated. Such streams are sometimes so low in their combustible content that one cannot even be sure that they will burn in such cases, there is frequently a voice in the background requesting an immediate estimate of the amount and value of primary fuel required to incinerate the gas stream. 

Accurately estimating the flammability of low-Btu gases has always been a problem. 

On such occasions, we pull a handbook off the shelf that contains a Flammability Table, examine the data for several of the most common compounds in the mix, notice that differences between compounds seem radical, then start searching for a common denominator, If some of the 

For constituents undergoing cracking reactions that absorb heat, the heating value of the fuel is  

For constituents undergoing cracking reactions that release heat, the heating value of the fuel is carbon energy, plus hydrogen energy, plus the heat of formation. Thus, the low heat value of acetylene is  

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