The large image on the left shows the prediction of a laboratory scale bubbling bed with the green region being coal particles. Steam and air are injected into the base of the gasifier as shown by the O2 and H2O plots. These react with the coal particles producing combustible gases including hydrogen, carbon monoxide and methane that can later be burned in a combustor. Other plots show the concentration and distribution of these species and the temperature within the fluidised bed gasifier.