How to improve the heat exchange efficiency of spiral plate heat exchanger during its application?

1. Increase logarithmic mean temperature difference: the flow patterns of spiral plate heat exchanger are countercurrent, downstream and mixed (both countercurrent and downstream). Under the same conditions, the logarithmic mean temperature difference is the largest in countercurrent and the smallest in downstream, and the mixed flow pattern lies between them. The method to improve the logarithmic mean temperature difference of spiral plate heat exchanger is to adopt countercurrent or near countercurrent mixed flow pattern as much as possible, increase the temperature of hot side fluid and decrease the temperature of cold side fluid as much as possible.

2. Determination of the position of inlet and outlet pipes: For the plate heat exchanger with single process layout, for the convenience of maintenance, the fluid inlet and outlet pipes should be arranged on the fixed end plate side of spiral plate heat exchanger as much as possible. The greater the temperature difference of the medium, the stronger the natural convection of the fluid, and the more obvious the influence of the stagnant zone formed. Therefore, the inlet and outlet positions of the medium should be arranged in such a way that the hot fluid goes up and down and the cold fluid goes in and out, so as to reduce the influence of the stagnant zone and improve the heat transfer efficiency.

3. Improve the heat transfer efficiency: the plate heat exchanger is a heat exchanger with partition wall. The cold and hot fluids transfer heat through the plates of the spiral plate heat exchanger, and the fluids directly contact with the plates. The heat transfer modes are heat conduction and convection heat transfer. The key to improve the heat transfer efficiency of plate heat exchanger is to improve the heat transfer coefficient and logarithmic mean temperature difference.

4. Improving the heat transfer coefficient of the heat exchanger. The heat transfer coefficient of the spiral plate heat exchanger can be effectively improved only by simultaneously improving the surface heat transfer coefficient of the cold and hot sides of the plate, reducing the thermal resistance of the fouling layer, selecting the plate with high thermal conductivity and reducing the thickness of the plate.