Optimization of\nthe Helium Extraction Process from\nNatural Gas with Integrated Cryogenic–Membrane Separation

Helium, recognized as a scarce and vital strategic resource,\nis\npredominantly extracted from natural gas through the cryogenic separation\nmethod. Nevertheless, conventional cryogenic separation processes\nare plagued by challenges, such as elevated energy consumption, diminished\nhelium extraction efficiency, and escalated production costs. Through\nthe study of various helium extraction methods and their technological\ncharacteristics, this paper proposes a novel natural gas cryogenic–membrane\nseparation helium extraction process coproducing ethane. Simulation\nof the process was performed with Aspen HYSYS. By calculating the\npercentage of equipment energy consumption, we analyzed the influence\nof the operating parameters on the equipment energy consumption, helium\nconcentration, and ethane recovery and then identified the main influencing\nparameters as optimization variables. Response surface analysis was\nused for process optimization, and central composite design was selected\nas the experimental design method; three regression models for equipment\nenergy consumption, ethane recovery, and crude helium concentration\nwere established, and process parameters were optimized and simulated\nfor validation. The maximum error of the three models was 0.772%.\nThe optimized process reduces the total energy consumption of the\nequipment by 3.301% while meeting the requirements of 89% ethane recovery,\n66.7% crude helium concentration, and 99.6% refined helium concentration.\nThis study can provide a theoretical foundation and technical guidance\nfor the operation and management of the cryogenic–membrane\nseparation method for helium extraction from natural gas.