1, temperature regulation: expansion heat exchanger through the use of the upper tower return flow of dirty nitrogen (or other low-temperature fluid) of the cold, after the expansion of the expansion of the air to cool. This step effectively reduces the temperature of the expanding air, thus reducing the superheat of the expanding air when it enters the upper tower. It helps to improve the energy efficiency of the air separation system.
2, cold recovery and distribution: in the air separation process, cold is a valuable resource. The expansion heat exchanger achieves the effective use of cold capacity by recovering the cold capacity in the dirty nitrogen and returning some or all of it to the system. This not only helps to improve the cold utilisation of the whole system, but also helps to improve the distillation process in the upper and lower columns. Optimise the operating efficiency of the system.
3, improve product quality: due to the presence of expansion heat exchanger, the moisture content of the air into the lower tower can be reduced. This helps to reduce the water content of the liquid at the bottom of the lower tower, thereby improving the purity of the liquid and air. Improvement of the purity of the liquid-air for the stability of the subsequent distillation process and product quality is critical.
4, optimise system energy consumption: through the reasonable design of the expansion heat exchanger process and parameters, can ensure product quality at the same time, reduce the energy consumption of the system. For example, by adjusting the flow rate and temperature of dirty nitrogen, you can optimize the heat transfer effect of the expansion heat exchanger and reduce unnecessary energy losses.
