Biogas Combustion in a Crater Bed

S. Tia, P. Chaivatamasath, V. Jumnongpon, S. Manomaiwong


The application of crater bed for simulated biogas (mixture of methane and carbon dioxide) combustion was studied. The effect of biogas composition, biogas to air ratio, bed particle size, and the height of burner tube on the circulation of bed particles and lower flammability limit (LFL) were experimentally examined. It was found that the circulation amount and height of bed particles increase in burner tube height caused a decrease in circulation height, while the amount of circulated particles increased. Under the study conditions, the values of LFL obtained for simulated biogas were 35% to 60% lower than those of standard conditions reported in the literature. With the preheating effect obtained from both hot gas and particle circulation, biogas containing CH4 as low as 7% vol (93% CO2) can be burned with stabilized flame in this crater bed.

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