Simulation and analysis of CH4/N2 separation by vacuum pressure swing adsorption with structured composite adsorption media

被引：0
|
作者：
Tian J. [1 ]
Shen Y. [1 ]
Zhang D. [1 ]
Tang Z. [1 ]
机构：
[1] State Key Laboratory of Chemical Engineering, Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin
来源：
Zhang, Donghui (donghuizhang@tju.edu.cn) | 1600年 / Materials China卷 / 72期
关键词：
Coalbed methane enrichment; Methane; Numerical simulation; Structured composite adsorption media; Vacuum pressure swing adsorption;
D O I：
10.11949/0438-1157.20210650
中图分类号：
学科分类号：
摘要：
To reduce methane emissions and achieve effective resource utilization of low concentration coalbed methane, the process of using a structured composite adsorbent for vacuum pressure swing adsorption to enrich low-concentration coal-bed methane was explored. The equilibrium adsorption capacities of pure gases (CH4 and N2) on the structured composite adsorption medium were measured under different pressures at a series of fixed temperatures by using the static volumetric method. Thus, a rigorous and reasonable mathematical model, including a set of conservation equation of mass, energy and momentum balances, was developed to precisely describe the dynamic behavior of multiple components in adsorption bed. A typical three-bed VPSA process with continuous feeding was designed and simulated. A comprehensive analysis was presented, relating to the process characteristics and performance such as temperature and pressure distribution in axial adsorption bed at cycle steady state. Additionally, effects of feed flow rate, desorption pressure, feed concentration and adsorption pressure on purity, recovery, energy consumption and productivity were investigated. The results showed that an effective separation performance of 59.07% CH4 purity, 93.64% CH4 recovery and 4.56 mol·h-1·kg-1 productivity with an energy consumption of 18.70 kJ·mol-1, was finally got with the optimal parameters, while the feed flow rate, desorption pressure, feed concentration and adsorption pressure were 100 L·min-1, 0.1 bar, 30% and 3 bar, respectively. Overall, this study indicated there is an effective adsorption and separation performance on CH4/N2 of structured composite adsorption media, which can achieve high-efficiency enrichment of methane in low concentration coalbed methane. © 2021, Editorial Board of CIESC Journal. All right reserved.
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页码：5675 / 5685
页数：10
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