氨制冷循环系统中过冷器的作用及其应用

The Role and Application of Subcooler in Ammonia Refrigeration Cycle

在煤化工项目中,为满足低温甲醇洗等装置的冷量需求,通常需设置氨制冷循环系统。氨制冷循环系统中冷凝器出口的饱和液氨过冷可提高单位质量液氨的制冷量,从而在冷量需求一定的情况下,减少液氨的用量和氨压缩机的功耗,实现节能。本文以单级氨制冷理论循环为例说明过冷器的作用,并得出过冷对制冷循环总是有利的,过冷度越大,则越节能的结论;通过分析四种实现过冷的方法,得到既可实现较大过冷度,又适用于氨制冷剂的方法为设置经济器,即第四种方法。某集团新建氨制冷循环系统采用了此方法,Aspen模拟结果显示,与无过冷的氨制冷循环系统相比,氨压缩机功耗降低了8.4%,实现了节能。

In coal chemical industry,in order to meet the cooling demand of low -temperature methanol wash unit, the ammonia refrigeration cycle system usually needs to be set. Supercooling the saturated liquid ammonia from condenser can improve the unit refrigerating capacity of liquid ammonia, reducing the amount of liquid ammonia and compressor power consumption and achieving energy saving under the situation in which cooling demand is certain. Based on the theory of single stage ammonia refrigeration cycle as an example, effect of subcooler is shown, and the conclusion that supercooling is always favorable to refrigeration cycle, the greater the degree of supercooling, the more energy - efficient is found out; By analyzing four kinds of implementation method of supercooling, setting the economizer, namely the fourth method, can achieve greater degree of supercooling and is suitable for ammonia refrigerant. This method is adopted in a newly - built ammonia refrigeration cycle system. Aspen simulation results show that, compared with the ammonia refrigeration cycle system wilh no subcooler, the compressor power consumption of this ammonia refrigeration cycle system with subcooler was reduced by 8.4%, achieving the energy saving.