The advantages of the plate heat exchanger are compact structure, and the heat exchange area provided by the unit volume equipment is large; the assembly is flexible, and the number of plates can be increased or decreased according to the need to adjust the heat transfer area; the plate surface of the plate heat exchanger makes the section change complicated, the fluid The disturbance effect is enhanced and has high heat transfer efficiency; the plate heat exchanger is convenient to disassemble and assemble, which is beneficial to maintenance and cleaning. The disadvantage is that the throughput is small; the operating pressure and temperature are not limited by the performance of the gasket material. The plate heat exchanger is suitable for frequent cleaning, and the working environment is very compact. The working pressure is below 2.5 MPa and the temperature is between -35 °C and 200 °C.