The plate heat exchanger is a new type of high-efficiency heat exchanger made of a series of metal sheets with a certain corrugated shape. Thin rectangular channels are formed between various plates, and heat is exchanged through the plates. Compared with conventional shell and tube heat exchangers, its heat transfer coefficient is much higher under the same flow resistance and pump power consumption, and it has a tendency to replace shell and tube heat exchangers within the applicable range. The plate heat exchanger is a heat exchanger made of metal plates pressed into heat exchange plates with a certain corrugated shape, which are then stacked and fastened with plywood and bolts. The working fluid flows through the narrow and tortuous channel formed between the two plates. The cold and hot fluids pass through the flow channel in turn, and there is an interlayer plate in the middle to separate the fluids, and heat is exchanged through this plate. The structure and heat exchange principle of the plate heat exchanger determine that it has the characteristics of compact structure, small footprint, high heat transfer efficiency, large operational flexibility, wide application range, small heat loss, easy installation and cleaning. The average temperature difference between the two media can be as small as 1°C, and the heat recovery efficiency can reach more than 99%.

There are two main types of plate heat exchangers: frame type (detachable type) and brazing type. There are three main types of plates: herringbone corrugated plate, horizontal straight corrugated plate and tumor-shaped plate.