Plate heat exchanger is a kind 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. Plate heat exchangers are ideal equipment for liquid-liquid, liquid-vapor heat exchange. It has the characteristics of high heat exchange efficiency, small heat loss, compact and lightweight structure, small footprint, wide application, and long service life. Under the same pressure loss, the heat transfer coefficient is 3-5 times higher than that of the tube heat exchanger, and the floor area is one-third that of the tube heat exchanger, and the heat recovery rate can be as high as more than 90%.
In general, we mainly distinguish plate heat exchangers based on their structure, that is, they can be divided into four categories: ① removable plate heat exchangers (also called plate heat exchangers with sealing gaskets) ② Welded plate heat exchanger, ③ Spiral plate heat exchanger, ④ Plate coil heat exchanger (also called honeycomb heat exchanger).
Among them, welded plate heat exchangers are divided into: semi-welded plate heat exchangers, fully welded plate heat exchangers, plate and shell heat exchangers, and brazed plate heat exchangers.
The following classifications are often used:
1 According to the amount of heat exchange area in the unit space, the plate heat exchanger is a compact heat exchanger, which is mainly compared with the shell and tube heat exchanger.
2 According to the process, there are different names: plate heater, plate cooler, plate condenser, plate preheater;
3 According to the combination of processes, it is divided into single-pass plate heat exchanger and multi-pass plate heat exchanger;
4 According to the flow direction of the two media, it is divided into a cocurrent (cocurrent) plate heat exchanger, a countercurrent plate heat exchanger, and a crossflow (cross flow) plate heat exchanger.
5 According to the gap of the flow channel, it is divided into conventional gap plate heat exchanger and wide gap plate heat exchanger;
6 According to the corrugation, the plate heat exchanger has more detailed differences, which will not be described in detail, please refer to: plate heat exchanger plate corrugated form.
7 According to whether it is a complete set of products, it can be divided into stand-alone plate heat exchangers and plate heat exchanger units.