不同净化工艺下氧气纯度对合成氨流程能耗的影响  

Effects of oxygen purity on energy consumption in synthetic ammonia processes under different purification processes

作　　者：王贤聪 江健荣 冯霄[1] 杨敏博 WANG Xian-cong;JIANG Jian-rong;FENG Xiao;YANG Min-bo(The School of Chemical Engineering and Technology,Xi'an Jiaotong University,Xi'an 710049,China)

机构地区：[1]西安交通大学化学工程与技术学院

出　　处：《高校化学工程学报》2019年第6期1465-1472,共8页Journal of Chemical Engineering of Chinese Universities

基　　金：国家重点研发计划(2018YFB0604800)

摘　　要：对于配备纯氧气化的合成氨工艺流程来说,空分单元的能耗巨大,具有较大节能潜力。如果适当降低氧气纯度,可以有效降低整个合成氨流程的能耗。同时,由于流率增大使得后续净化单元的操作费用有所增加,这样就存在一个整个流程能耗最低的最优纯度。研究应用Aspen Plus软件对甲烷化精制工艺下的工业合成氨全流程进行模拟并与液氮洗精制工艺进行了全面对比分析,着重考虑了空分所产氧气的纯度对于整个系统的影响。结果表明,氧气纯度的变化对净化工段的能耗有一定影响,两种净化流程所得能耗与氧气纯度的关系曲线走势十分相似。通过能耗与操作费用的对比,确定了92%氧气纯度的液氮洗工艺流程是合成氨的最优方案,对实际生产有一定指导作用。For synthetic ammonia processes using pure oxygen, the energy consumption of air separation unit is huge that has great potential for energy saving. If the oxygen purity can be properly reduced, the energy consumption of the whole ammonia process can be reduced effectively. Meanwhile, the operation cost of the subsequent purification unit increases due to the increase of flow rate. Therefore, there is an optimal oxygen purity which makes the whole process energy efficiency. Aspen Plus was used to simulate the whole industrial ammonia synthesis process with methanation refining, and the results were compared with the liquid nitrogen purification process. Effects of oxygen purity from air separation were considered. The results show that the purity of oxygen has certain effects on energy consumption of purification, and the profiles of energy consumption against oxygen purity obtained by the two processes are very similar. After comparative analysis of energy consumption and operational cost, the liquid nitrogen washing process with 92% oxygen purity is found as the optimal solution for ammonia synthesis. This result is useful for practical production.

关 键 词：合成氨 氧气纯度 甲烷化净化 液氮洗净化 Aspen Plus 

分 类 号：TQ021.8[化学工程]