Abstract: According to the invention, the fuel is supplied to the reformed-gas generator in an amount at least approximately proportional to the instantaneous demand of the internal-combustion engine and is mixed there, in atomized or evaporated form, with so much air and/or fed-back exhaust gas drawn in through the reformed-gas generator that for the air component of the mixture, the air number for the reaction of the fuel in the converter is at least 0.05 but not more than 0.5 and the exhaust gas component does not fall below the exhaust gas quantity equivalent to the air number 0.05 and does not exceed the exhaust gas quantity equivalent to the air number 0.5. The fuel gas mixture produced in this manner, prior to being fed to the combustion chambers of the internal-combustion engine, is mixed with enough additional air sucked in by the internal-combustion engine such that the air number for the combustion in these combustion chambers is at least equal to 1.

Abstract: A fuel gas obtained in a reformed gas generator through the catalytic reaction of hydrocarbons and a gas containing oxygen and provided to an internal combustion engine has its heat content along with that of the exhaust gas of the engine used to convert methonal endothermically into a gas mixture containing carbon monoxide and hydrogen with the gas mixture so formed fed to one or both the reformed gas generator and, along with the fuel gas, the internal combustion engine.