Heat exchanger

The utility model provides a heat exchanger which comprises a cylinder, a connecting pipe arranged at the bottom end of the cylinder and a pipe box cylinder body arranged at the top end of the cylinder. One end of the connecting pipe is matched and connected with the bottom end of the cylinder through a flange and a bolt. Condensate generated after heat exchange treatment of the heat exchange pipe is discharged through the condensate liquid outlet pipe, and gas generated after heat exchange treatment of the heat exchange pipe is discharged through the exhaust pipe; and a flange is connected with an external pipeline for discharging, so that the water-gas separation work is effectively carried out. The water scale removing agent in the water tank is pumped out through the water pump and conveyed into the cylinder through the water pipe, and water scale, rust scale and other sediments in the cylinder are degraded. Meanwhile, the incrustation scavenger can form a protective film in the cylinder, corrosion in the