Cooling protection device for downcomer of gasification furnace

The utility model discloses a gasification furnace downcomer cooling protection device which comprises a combustion chamber and a chilling chamber, the bottom end of the combustion chamber is connected with a cone bottom, the bottom end of the cone bottom is connected with a chilling ring through a flange, the chilling ring is connected with a downcomer, the downcomer is arranged in the chilling chamber, and the other end of the downcomer is provided with a slag outlet. A plurality of spray holes are uniformly distributed and connected in the inner side of the downcomer of the chilling ring, a water jacket cylinder is welded and sleeved outside the downcomer, a chilling water inlet is connected to the bottom of the water jacket cylinder, a branch pipe is connected to the chilling water inlet, an annular baffle is connected between the top end of the water jacket cylinder and the downcomer, and a plurality of through holes are connected to the annular baffle; and a gap is connected between the water jacket cyl