Date of Publication:2019-01-01

Journal:化工学报

Volume:70

Issue:7

Page Number:2556-2563

ISSN:0438-1157

Abstract:Industrial helium is mainly extracted from natural gas by cryogenic, membrane separation and pressure swing adsorption(PSA) coupling of which PSA is the key to obtain high purity helium. It is helpful to overcome experimental limitations via adsorption process simulation, which can effectively guide engineering design and optimize process conditions. A helium/methane single-column pressure swing adsorption model was established by Aspen Adsorption software to obtain breakthrough curves. Based on the results, a two-column PSA process was established. The optimal operation time of adsorption, forward, reverse, flush, and boost step is 60, 180, 30, 60 and 180 s, through analyzing the changes of the gas phase composition in the adsorption column. In three-column PSA process, the optimal time of adsorption and pressure equalization for one cycle are 135 s and 90 s, helium purity can reach 98.42% and the recovery is up to 60.45%. It is necessary to optimize the cycle time in one cycle by considering the matching of each step time and the continuity of production in five-tower PSA process. When cycle time is between 300 s and 340 s, purity of helium reaches 99.07%.

Note:新增回溯数据