Coal gasification device for circulating fluidized bed and manufacturing method thereof

[0008] The technical solution given by the present invention is: this circulating fluidized bed coal gasification device includes a coal feeding system composed of coal crushing, screening equipment, coal storage tank and feeding bin, generator, cyclone dust collector, waste heat boiler , a water cooling tower and a Venturi scrubber, wherein the bottom of the feeding bin is provided with a spiral coal feeder for feeding coal to the producer, the producer is provided with upper and lower gasification agent nozzles, and the bottom of the producer is provided with a spiral Ash removal machine and ash storage tank, the upper part of the generator is provided with a gas pipe connected to the upper end of the cyclone dust collector, the bottom of the cyclone dust collector is provided with a return pipe connected with the generator furnace, and the cyclone dust collector is connected with the waste heat boiler through the gas pipe, and the waste heat The boiler communicates with the water-cooling tower through the gas pipe, and the water-cooling tower communicates with the Venturi scrubber through the gas pipe. It is characterized in that the return pipe from the lower end of the cyclone dust collector to the generating furnace is a feeder with a small fluidized bed. The amount of returned material can be dynamically adjusted, effectively realizing two key functions: one is to make the recirculated bed material return to the furnace continuously and stably from the cyclone dust collector; the other is to provide a gap between the negative pressure of the cyclone dust collector and the positive pressure of the lower combustion chamber The seal of the feeder is composed of a standpipe, a wind cap or an air duct, a bottom air chamber, a side air chamber, a return pipe, a fluidization chamber, a horizontal air distribution plate and a longitudinal air distribution plate, and the feeder is equipped with There are horizontal air distribution boards and vertical air distribution boards, and the space in the feeder is divided into three parts: the fluidization chamber, the bottom air chamber and the side air chamber. One end of the standpipe is connected with the cyclone dust collector. The other end is connected to the fluidization chamber, one end of the return pipe is connected to the fluidization chamber, and the other end is connected to the generator. The high-pressure gas from the blower enters the bottom air chamber and the side air chamber through the air inlet pipe. The backflow dust in the fluidization chamber is blown by the wind cap or air pipe on the air distribution board to form a small fluidized bed. A negative pressure zone is formed in the area below the joint, which not only facilitates the fly ash from the cyclone dust collector to enter the fluidization chamber smoothly through the standpipe, but also solves the problem of U-shaped, J-shaped, L-shaped return feeders in the prior art. The problem that the standpipe reverses and the amount of fly ash cannot be circulated back to the furnace through the return pipe when the amount of fly ash is small