Fractional gasifying furnace for coal and coke gasification

The present invention is one stepped gasifying furnace for gasifying coal and coke to produce coarse gas containing CO and H2. The stepped gasifying furnace includes pressure resisting casing, refractory layer, coarse gas outlet, cinder outlet, water chilling system in the lower part of the furnace body, and feeding burner in the top to supply oxygen and fuel. It features the secondary oxygen nozzle set in the reflux region of the furnace body to regulate oxygen distribution inside the furnace and establish different temperature regions, so as to optimize the reaction condition, prolong the service life of the feeding burner and raise the volume utilizing rate of the furnace.