Abstract: A device for making high temperature reformed gas from coke oven gas and blast furnace gas comprises a continuous heating apparatus for preheating a coke oven gas; and a first system including (a) an intermittent heat exchanger containing therein a packing bed of the heat-accumulator type for preheating a blast furnace gas; (b) a separate cyclone-type gas mixing chamber for mixing the preheated raw gases; and (c) an intermittent reforming furnace containing therein a packing bed of the heat-accumulator type impregnated with a catalyst. A second system comprising counterpart elements (a), (b) and (c) is connected to the apparatus (a) in parallel with the first system so as to be operated alternately with said first system. Bypass valves are preferably provided to feed the blast furnace gas directly to the gas mixing chamber bypassing the intermittent heat exchanger.