1. The plate heat exchanger has a high heat transfer coefficient. Since different corrugated plates are inverted each other to form a complex flow channel, the fluid flows in a three-dimensional rotating flow in the flow channel between the corrugated plates, and can produce turbulent flow at a low Reynolds number (generally Re=50~200), so heat transfer The coefficient is high, generally considered to be 3 to 5 times that of the shell-and-tube heat exchanger.　　

2. The logarithmic average temperature difference of the plate heat exchanger is large, and the temperature difference at the end is small. In the shell-and-tube heat exchanger, the two fluids flow in the tube side and the shell side respectively, and the flow is generally cross-flow, and the logarithmic average temperature difference correction coefficient is small, while the plate heat exchanger mostly adopts co-current or counter-current flow. , The correction factor is usually around 0.95. In addition, the flow of cold and hot fluids in the plate heat exchanger is parallel to the heat exchange surface and has no side flow, so that the temperature difference at the end of the plate heat exchanger is small, and the heat transfer to water can be lower than 1℃, while the shell-and-tube heat exchanger The heater is generally 5°C.　　

3. The plate heat exchanger occupies a small area. The plate heat exchanger has a compact structure, and the heat exchange area per unit volume is 2 to 5 times that of the shell and tube type. Unlike the shell and tube heat exchanger, there is no need to reserve a tube bundle inspection place, so the same heat exchange can be achieved , The floor area of the plate heat exchanger is about 1/5~1/10 of that of the shell and tube heat exchanger.　　

4. The plate heat exchanger is easy to change the heat exchange area or process combination. As long as a few plates are added or reduced, the purpose of increasing or reducing the heat exchange area can be achieved. Changing the plate arrangement or replacing several plates can achieve the required process combination and adapt to the new heat exchange conditions. However, the heat transfer area of the shell-and-tube heat exchanger is almost impossible to increase.　　

5. The plate heat exchanger is light in weight. The plate thickness of the plate heat exchanger is only 0.4~0.8mm, while the thickness of the heat exchange tube of the shell-and-tube heat exchanger is 2.0~2.5mm. The shell of the shell-and-tube heat exchanger is larger than the frame of the plate heat exchanger. It is much heavier, and the plate heat exchanger is generally only about 1/5 of the weight of the shell-and-tube heat exchanger.　　

6. The price of plate heat exchanger is low. Using the same material, under the same heat exchange area, the price of the plate heat exchanger is about 40% to 60% lower than that of the shell and tube heat exchanger.　　

7. The plate heat exchanger is easy to manufacture. The heat transfer plate of the plate heat exchanger is processed by stamping, which has a high degree of standardization and can be mass-produced. The shell-and-tube heat exchanger is generally made by hand.　　

8. The plate heat exchanger is easy to clean. As long as the detachable plate heat exchanger loosens the compression bolts, the plate bundle can be loosened, and the plates can be removed for mechanical cleaning. This is very convenient for the heat exchange process that requires frequent cleaning of the equipment.　　

9. The heat loss of the plate heat exchanger is small. Only the shell plate of the heat transfer plate of the plate heat exchanger is exposed to the atmosphere, so the heat dissipation loss can be neglected, and no heat preservation measures are required. The shell-and-tube heat exchanger has a large heat loss and requires a thermal insulation layer.　　

10. The plate heat exchanger has a small capacity. The capacity of the plate heat exchanger is about 10%-20% of the shell-and-tube heat exchanger.　　

11. The pressure loss per unit length of the plate heat exchanger is large. Due to the small gap between the heat transfer surfaces and the unevenness on the heat transfer surface, the pressure loss of the plate heat exchanger is greater than that of the traditional smooth tube.

12. The plate heat exchanger is not easy to scale. Because the inside of the plate heat exchanger is fully turbulent, it is not easy to foul, and its fouling coefficient is only 1/3~1/10 of that of the shell-and-tube heat exchanger.　　　　

13. The working pressure of the plate heat exchanger should not be too high, and the temperature of the medium should not be too high, as it may leak. The plate heat exchanger is sealed with a gasket. The working pressure should generally not exceed 2.5MPa, and the temperature of the medium should be lower than 170°C, otherwise it may leak.　　

14. The plate heat exchanger is easy to block. Since the passage between the plates of the plate heat exchanger is very narrow, generally only 2~5mm, when the heat exchange medium contains larger particles or fibrous substances, it is easy to block the passage between the plates.