SURFACE MELTING FURNACE OF BURNT ASH

PROBLEM TO BE SOLVED: To provide a surface melting furnace capable of preventing mixing of fly ash and drop of the in-furnace temperature during the water granulation, and capable of providing the slag of arbitrary size. SOLUTION: A surface melting furnace comprises a melting chamber 6a of fire-proof structure having an inclined hearth to flow the raw ash 1a in one direction, a flue chamber 6b of fire-proof structure which is installed below the melting chamber and communicated with the melting chamber, a water tank 12 provided with a screw conveyor 17 for feeding the slag below the flue chamber, and a burner 5 to eject the flame of high temperature to the raw ash, the molten raw ash is dropped from the inclined hearth into the water tank, and an air blowing means 7 is fitted to an upper part of the water tank. The melting chamber which has the inclined hearth to drop the raw ash in one direction and is provided with a fire-proof structure, the flue chamber which is installed below the melting furnace 6 and communicated with the melting furnace, and the burner to blow the flame against the raw ash flowing down on the inclined hearth are provided so that the molten raw ash can be taken outside.