Nitrogen detection equipment for closed spray dryer

The utility model discloses nitrogen detection equipment of a closed spray dryer. The device comprises a first shell and a second shell, the first shell and the second shell are in threaded connectionwith each other; a groove is formed in the second shell; a clamping groove is formed in the bottom of the groove; an elastic film is clamped in the clamping groove; an inner cavity of the second shell is connected with a cylinder in a sliding manner; the lower end of the cylinder and the elastic film are fixedly installed. A second end cover is connected to the upper end of the second shell in athreaded mode, a through round pipe is fixedly installed on the second end cover, a pressure sensor is installed at the lower end of the round pipe, a through cylinder is fixedly connected to the sideface of the first shell, a valve element is slidably connected to an inner cavity of the cylinder, and a first end cover is installed at the right end of the cylinder. The air pressure in the pipeline is indirectly reflected b