Abstract
Representative low-Btu gas mixtures derived from coal are presented and simplified, resulting in synthetic low-Btu gas mixtures composed of H2, CO, CH4, N2, and CO2. Mine-atmosphere flammability data are applied to the synthetic mixtures to produce flammability limits at one atmosphere and 77 °F. Two-component synthetic mixtures of CH4 and an inert gas are shown to be not suitable for certain combustion experiments requiring low-Btu gases.