The cooling furnace is mainly used for the cooling of building gypsum. It is an efficient special equipment with the application of fluidization technology. The main body of the cooling machine is a rectangular container, and there is a porous plate of gas distribution at the bottom, which is connected with the bellows. There is a longitudinal partition in the furnace body, which divides the furnace body into two parts, the main furnace and the paying furnace, and many heating pipes are installed in the two parts. The upper part of the furnace body is equipped with a dust box, which is integrated with the furnace body. In normal operation, the furnace is filled with powder, and a small amount of air is blown into the bottom of the furnace through the gas distribution plate, so that the powder can achieve fluidization. The heat of the building plaster is transferred to the air through the wall of the heat dissipation pipe.