Medium temperature rules for efficient operation of Teflon heat exchangers

Medium temperature rules for efficient operation of Teflon heat exchangers:

Teflon heat exchangers are widely used in waste heat recovery and thermal systems. In order to obtain economic benefits, it is necessary to participate in the optimization design of heat exchangers. Teflon heat exchangers can recover heat energy, but increase investment and operating costs. The optimization design of Teflon heat exchangers is not a good way to unify. It is recognized that more practices are to adopt multiple heat transfer efficiency units (E-NTU) methods.

The heat exchanger temperature depends on the process conditions. Although we hope to increase the heat transfer and heat transfer temperature and pressure intensity, the medium temperature is too high or too low. Scaling, precipitation and crystallization may occur, but the heat transfer is deteriorated. At the same time, the choice of medium temperature has an important influence on the choice of wall materials and thermal compensation requirements. It is not worth pursuing high efficiency and economy.

The hot end temperature is not less than 20°C, the cold end temperature difference is not less than 5°C, the initial temperature of the cooler or condenser of the coolant should be higher than the freezing point of the liquid to be cooled, the condensation of non-condensable gas, the final temperature of the coolant is 5°C lower than the dew point temperature of the condensing gas, and the air outlet and inlet of the hot fluid should be no less than 20°C air cooling temperature. These indicators can be calculated by technology and economy. Of course, these indicators should be considered comprehensively according to different occasions and purposes.

The evaluation of Teflon heat exchangers should be based on technical and economic analysis, comprehensive consideration, such as technology, economy, safety, manufacturing, installation, operation and maintenance and material requirements, especially the improvement projects of energy-saving heat exchangers should pay attention to the heat transfer coefficient K under the same pressure conditions, the heat exchanger efficiency, equipment investment, operating costs and other technical and economic indicators, on a comparable basis, such evaluation has a general guiding significance.