The invention discloses a device for removing
sulfur trioxide from
smoke. The device comprises a bin, a screw feeder, a
smoke delivery
pipe, a spray gun, a denitration inlet
flue, a denitration reactor and a
spoiler, wherein the screw feeder is provided with a feeding opening and a discharging opening, and the feeding opening is connected with the bin and used for controlling the discharging rate of an absorbent; the
smoke delivery
pipe is provided with a smoke inlet and a smoke outlet, and the discharging opening is connected with the smoke delivery
pipe; the smoke outlet is connected with the spray gun, and the spray gun is used for spraying the absorbent for strong alkaline particles; the denitration inlet
flue is used for mixing the absorbent with smoke, and the smoke outlet and the spray gun are positioned in the
flue; the denitration reactor is connected with the denitration inlet flue. The device can be applied to a
coal firing unit of a thermal power
plant, effectively reduce the SO3 content, reduce the influence of the
sulfur trioxide on the denitration device and an air pre-heater, and reduce pollutants to realize smoke clean emission.