Ammonia spraying device of denitration system

The utility model discloses a denitration system ammonia spraying device which comprises a mixing box and a driving box, the driving box is installed at the top end of the mixing box, supporting sleeves are arranged on the outer walls of the two sides of the mixing box, mixed gas pipes are arranged in the supporting sleeves, one end of each mixed gas pipe extends into the mixing box, and the other end of each mixed gas pipe extends into the mixing box. The other end of the mixed gas pipe extends to the outside of the mixing box, two groups of hinge seats are arranged in the mixing box, driving arms are arranged on the outer walls of the hinge seats, driving frames are mounted at the bottom ends of the driving arms, two groups of nozzles are arranged at the bottom ends of the driving frames, and an annular sleeve is mounted in the mixing box. A flue gas pipe is mounted on the outer wall of the mixing box on one side of the annular sleeve, and one end of the flue gas pipe extends into the annular sleeve. Accord