A cascaded model is proposed for SYNGAS refinement. The first stage has a bypass outlet to transfer some SYNGAS to the output. Also, both stages have adjustable steam inputs controlling the amount of steam supply to both reactors separately; hence SYNGAS characteristics at the output can take the desired form. Satisfying the constraints of H-2/CO ratio at reactor exit was emphasized. SYNGAS composition fed into the first stage characterizes the overall behavior. Hence, the structured model has the capability to refine any SYNGAS composition by identifying the proper process parameters of a given coal type for desired SYNGAS properties. The model was tested with three different coal types, and in each case the best bypass values and steam ratios were obtained.