煤化工装置燃料气系统优化探讨

Optimization of fuel gas system in coal chemical plant

根据燃料气系统运行现状,提出了两个燃料气系统优化方案,以解决目前燃料气系统无法完全满足下游生产装置需要、排放量过大的问题,达到减少燃料气排放、提高能源利用率、降低企业运行成本的目的。并对两个优化方案进行物料衡算和经济效益核算,分别验证两个方案的可行性和经济性。通过对比两种方案,得出方案一(对现有燃料气管网进行改造,将含烯烃、甲醇较多的燃料气单独送至动力装置,并对现有PSA氢回收装置进行扩能改造,使回收气量达23778.4m3/h)优于方案二(维持PSA氢回收装置目前运行状态,增加一套尾气回收装置回收甲醇弛放气中的CO、H2,使燃料气系统达到物料平衡)。方案一具有可行性高、投资小、操作维护方便、经济效益高的优点,是两种优化方案中的最佳选择。

This paper presented two optimization plans aiming at the solution of high flue gas emissions based on the existing conditions of flue gas exhaust in a coal chemical plant. The purpose was ultimately to reduce emissions,improve energy efficiency,and save operation cost. The material balance and the economic benefits of the two proposed plans were analyzed and compared. The results showed that plan No.1（modify the existing fuel gas pipe network,send the fuel gas line full of olefins and methanol to the Power plant,expand the hydrogen recovery capacity of PSA,make the gas volume of recovering reach 23778.4m3/h） was better than plan No.2（maintain the currently running state of PSA unit,build a tail gas recovery device for recovering CO and H2 from methanol purge gas,then the fuel gas system can achieve material balance）,in terms of feasibility,low investment,more convenient for operation and maintenance.