Yaojie Coal and Electricity Group Co.
China Coal Research Institute Co.,Ltd.
Beijing Key Laboratory of Coal Based Carbon Materials
National Energy Technology & EquipmentLaboratory of Coal Utilization and Emission Control

氦气是国家重要战略气体之一,天然气提氦是其主要工业来源。我国由于缺少天然气资源严重受制于氦垄断国家,寻找新的氦气提取资源迫在眉睫。从与天然气组成类似,且不需复杂前处理的浓缩煤层气中提取氦气可作为破除我国氦气“卡脖子”的重要方向。利用AspenHYSYS软件对浓缩煤层气提氦联产液化天然气(LNG)工艺进行模拟计算,分析了提氦塔的进料温度、进料压力、回流比、理论板数与进料位置及原料气组成等参数对深冷液化提氦工艺能耗、粗氦和LNG产品质量的影响。结果表明:浓缩煤层气深冷液化提氦工艺主要耗能设备为循环制冷过程中的压缩机和膨胀机,提氦过程中的冷凝器和再沸器。进气低温、高压条件下,深冷液化提氦分离效果好。一、二级提氦塔和脱氮塔的理论板数分别为8、7和4时,深冷液化提氦系统投资费用最低,经济性好。原料气中CH4体积分数由86%提高至93%,He体积分数由0.8%提高至1.5%,N2体积分数由13.2%降至5.5%时,经两级低温冷凝提氦后产品粗氦体积分数由66.68%提高至70.49%,He回收率由99.67%提高至99.93%,粗氦产量由7.47m3/h提高至13.28m3/h。针对15000m3/d生产规模,浓缩煤层气深冷液化提氦系统总投资约1946万元,其中氮气循环制冷压缩机占比最大,约65.58%。针对浓缩煤层气,采用深冷液化工艺可实现粗氦制取同时联产液化天然气(LNG),对煤层气提氦工艺工业应用提供支持。

Helium is one of the important national strategic gases, and the extraction of helium from natural gas is its main industrialsource. China is severely constrained by helium monopoly countries due to the lack of natural gas. It is extremely urgent to find the new resources for helium extraction. Helium extraction from concentrated coalbed methane, which is similar to natural gas and does not require complex pretreatment, could be an important direction for China to break the helium " stuck neck" . The extraction of heliumfrom concentrated coalbed methane with the co-production of LNG was simulated by Aspen HYSYS, and the influence of intake air temperature, intake air pressure, reflux ration, theory plate number, feed position and composition of feed gas on the energy consumption ofhelium extraction by cryogenic liquefaction, crude helium and LNG quality was analyzed. The results show that the main energy consumingequipments of helium extraction from concentrated coalbed methane by cryogenic liquefaction are compressor and expander from cycle refrigeration, condenser and reboiler from helium extraction, respectively. The separation effect of helium extraction by cryogenicliquefaction is better under the conditions of low temperature and high pressure of inlet gas. The investment cost of helium extraction bythe cryogenic liquefaction is the lowest and the economy is good, when the number of theoretical plates of the primary and secondary helium extraction tower and denitrification tower are 8, 7 and 4, respectively. The concentration of crude helium is increased from 66.68% to70.49%, the recovery rate of helium is increased from 99.67% to 99.93%, and the output of crude helium is increased from 7.47 m3 / h to13.28 m3 / h by two-stage low-temperature condensation, with the CH4 concentration of the feed gas is increased from 86% to 93%, theHe concentration is increased from 0.8% to 1.5%, and the N2 concentration is reduced from 13.2% to 5.5%. For the production scale of15 000 m3 / d, the total investment of the cryogenic liquefaction helium extraction system of concentrated coalbed methane is about19.46 million RMB, of which the nitrogen cycle refrigeration compressor accounts for the largest proportion, about 65.58%. The crude helium and coproduct liquefied natural gas (LNG) can be produced from concentrated coalbed methane by cryogenic liquefaction which willbe helpful for industrial application of helium extraction from coalbed methane.

许继宗,李雪飞,袁崇亮,等.浓缩煤层气深冷液化提氦工艺[J].洁净煤技术,2023,29(11):167-177.

XU Jizong,LI Xuefei, YUAN Chongliang, et al. Helium extraction process by cryogenic liquefaction of enriched coalbed methane[J].Clean Coal Technology,2023,29(11):167-177.