LNG冷能空分装置优化改造

摘要

LNG assist air separation unit has the advantages of low energy consumption and low operating cost,but at present,there is a widespread problem for LNG assist air separation unit,which starts and shuts down frequently,has seriously affected the operation of air separation unit and economic benefits,need to be solved.The first air separation unit in the domestic was researched,and the cause and effect of the frequent shutdown of the air separation unit were analyzed,according to the condition of equipment,proposing the use of liquid nitrogen solution,with the help of Aspen Plus simulation software.The air separation unit was simulated and remolded.Simulation results show that the area of heat exchanger is 69.61 m2,and the quantity of liquid nitrogen cold energy is 18 110 kg/h.Through the analysis for the economic benefits of the scheme,using liquid nitrogen cold energy supply scheme can avoid the frequent shutdown of air separation,and improve the economic benefit of the project.%LNG冷能空分装置具有能耗低、运行费用低等优势,但是目前LNG冷能空分装置普遍存在频繁开停机问题,严重影响了空分装置的生产运行和经济效益,亟待解决.文中以国内首套冷能空分装置为研究对象,对冷能空分频繁停机的原因和结果分析,根据设备自身状况,提出利用液氮冷能方案,借助Aspen Plus模拟软件对空分装置进行模拟优化改造.模拟结果表明:换热器所需换热面积为69.61 m2,需要液氮冷能18 110 kg/h.通过对方案经济效益分析可知,采用液氮冷能供应方案,可避免空分装置频繁停机,提高了项目经济效益.