The invention discloses an automatic
powder feeding device which comprises a level indicator device, a
screw conveyor, an ash conveying pipeline, a high-pressure fan, an observation window access hole, a
crawling ladder, a
powder feeding protection device, a feed cylinder, and a
powder feeding guardrail. The
crawling ladder is arranged on the side of a support frame; one end of the
crawling ladderis connected with the support frame; the other end of the crawling ladder is connected with the crawling ladder and the powder feeding protection device; the level indicator device, the
screw conveyor, the ash conveying pipeline, the high-pressure fan, the observation window access hole, a speed
reducer, an ash hopper and a tank are arranged in the support frame; the side of the top end of the support frame is connected with the top end of the ash hopper; the observation window access hole and the level indicator device are arranged on an outer side panel of the ash hopper; the speed reduceris arranged under the ash hopper; and the
screw conveyor is connected to the side of the speed
reducer. According to the automatic powder feeding device provided by the invention, when a deduster works, a
lime powder feeder is arranged according to the
system parameters, and the powder feeding rate per hour is set according to the demand of an owner, so that the automatic powder feeding device isstable to work, high in efficiency and convenient to use.