Multi-technology integrated separation process for producing high-purity helium from liquefied tail gas of helium-rich natural gas

• Main Authors: HE GAOHONG, JIANG XIAOBIN, XIAO WU, ZHENG WENJI, RUAN XUEHUA, WANG JIAMING, DAI YAN, GUO MINGGANG, YAN XIAOMING
• Format: Patent
• Language: Chinese; English
• Published: 23.07.2021
• Subjects: BLASTING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; HEATING; LIGHTING; LIQUEFACTION SOLIDIFICATION OF GASES; LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS; MANUFACTURE OR STORAGE OF ICE; MECHANICAL ENGINEERING; MIXTURES BY PRESSURE AND COLD TREATMENT; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; REFRIGERATION OR COOLING; SEPARATION; TRANSPORTING; WEAPONS

The invention relates to a multi-technology integrated separation process for producing high-purity helium from helium-rich liquefied natural gas tail gas, which comprises the following steps: helium-containing tail gas from a natural gas liquefaction device enters a multi-stage circulating membrane separation unit for preliminary enrichment after being subjected to cold energy recovery and pressurization; crude helium obtained through membrane separation enters a catalytic oxidation dehydrogenation unit after being pressurized, then enters a compression condensation and temperature swing adsorption dehydration unit and finally enters a low-temperature pressure swing adsorption purification unit, and high-purity helium is obtained; and desorbed gas of the adsorption unit returns to a membrane separation unit. Through multi-technology gapless matching and synergistic interaction, it is guaranteed that each impurity is removed in a proper mode, high-purity helium with the purity being 99.99 vol% is obtained, th