文献类型：期刊文献

英文题名：An improved vacuum pressure swing adsorption process with the simulated moving bed operation mode for CH4/N2 separation to produce high-purity methane

作者：Qian, Zhiling[1];Yang, Ying[1];Li, Ping[1];Wang, Jin[1];Rodrigues, Alirio E.[2]

机构：[1]East China Univ Sci & Technol, Sch Chem Engn, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]Univ Porto, Lab Separat & React Engn LSRE, Associated Lab LSRE LCM, Dept Chem Engn,Fac Engn, Rua Dr Roberto Frias S-N, P-4200465 Porto, Portugal

年份：2021

卷号：419

外文期刊名：CHEMICAL ENGINEERING JOURNAL

收录：;EI(收录号：20211610219161);WOS:【SCI-EXPANDED(收录号:WOS:000663664200001)】；

基金：The authors wish to acknowledge National Natural Science Foundation of China (No. 21978090, No. 21776089, No. 51804127), the International S&T Cooperation Program of China (No. 2016YFE0132500). The authors wish to acknowledge Dr. Porfirio Ferreira Alexandre Filipe and Dr. Ana Mafalda Ribeiro in University of Porto for the help of setup experimental device of gas phase simulating moving bed.

语种：英文

外文关键词：Methane enrichment; CH4/N-2 separation; VPSA process; Gas phase SMB process

摘要：Methane is a clean fossil fuel and an important greenhouse gas, so it is more significant to recover methane from massive resources of unconventional gas. Because of the similar physicochemical properties of methane and nitrogen, it is difficult to obtain the high-purity methane from the low-grade methane gas with nitrogen mixture by the conventional vacuum pressure swing adsorption (VPSA) process. In this work, this process was improved, where multicolumn in series operation was adopted at both adsorption and displacement steps to enhance the CH4/N-2 separation, and one column went on blowdown, purge, and pressurization steps for the effective regeneration of the adsorbent. In order to run the improved VPSA process automaticly, the SMB operation mode was introduced, synchronously shifting the inlet and outlet stream ports from one column to other column along the gas flow direction, and a countercurrent contact between the gas phase and adsorbent phase in the multicolumn system was formed to enhance the CH4/N-2 separation. To verify the feasibility of the improved VPSA process, the experimental device with eight-column unit had been set up in laboratory, and 30% similar to 50% CH4 gases were denitrified by the improved VPSA process using activated carbon beads. The experimental results demonstrated that the improved VPSA process was capable of producing a high-purity CH4 product gas (99.99% CH4) meeting pipeline grid specification and a high-concentration N-2 by-product gas meeting emission standards from 30% similar to 50% CH4 feed gases. In the end, we compared the CH4/N-2 separation performance among the conventional VPSA process, dual reflux-pressure swing adsorption process, improved VPSA process with SMB operation mode, CO2 displacement VPSA process and concentration temperature swing adsorption process.