As the design philosophy of a silo combustor differs largely from the better known one of smaller can type combustors, the paper describes the impact of alternative fuels on the burner concepts and emission characteristics of the silo combustor. Some published influences of a higher C/H-ratio on wall temperatures and smoke emission could not be observed. The large volume of the silo combustor offers the possibility of burning coal derived gases with heat values as low as 1800 kJ/kg. Nitrogenous liquid fuels need a rich burning first combustion stage with a long residence time. Calculations which closely agree with latest published test results show the pronounced effect of residence time to the rich burn quick quench concept. This becomes even more distinct in the case of a low BTU coal gas containing NH 3 or HCN resulting in unrealistic large combustor volumes. In addition, a general graph based on kinetic calculations shows the expected NO x increase or decrease of any kind of CO, H 2 and inert concentration in a coal gas related to the NO x result of methane in the same combustor.