Effect of two-step pressurization with intermediate gas on rapid vacuum pressure swing adsorption process for oxygen generation

doi:10.11949/j.issn.0438-1157.20160191

Abstract

Abstract:

An improved rapid vacuum pressure swing adsorption (RVPSA) process, namely, two-step pressurization with intermediate gas, was proposed to improve performance of miniature oxygen concentrators, which were based on rapid pressure swing adsorption (RPSA) technology. The experimental results on the new process show that pressurization with intermediate gas at the exhaust end could effectively improve oxygen purity and re-pressurization with intermediate gas at the feed end could improve recovery. The pressure and oxygen purity of intermediate gas at the exhaust end before pressurization as well as the bed pressure after re-pressurization of intermediate gas at the feed end were key parameters for improving oxygen purity and recovery of the production. At the adsorption pressure of 240 kPa and the desorption pressure of 60 kPa, the improved RVPSA process exhibited recovery of recycling oxygen up to 34.57% and the BSF at 61.18 kg·TPD^-1 for producing a ton of oxygen per day.

Key words: adsorption, separation, oxygen generation, pressurization, numerical simulation

摘要：

针对快速变压吸附制氧浓度和回收率低问题，提出了用于提高产氧浓度和回收率的中间气两步充压的快速真空变压吸附流程，并对该流程进行了研究。结果表明：在快速真空变压吸附制氧过程中，中间气先在出气端充压可以有效提高产氧浓度，之后再在进气端充压可提高氧气回收率。出气端充压前中间气压力及氧浓度和进气端充压后床层压力是影响产氧浓度和回收率提高的关键参数。当吸附和解吸压力分别为240、60 kPa时，循环氧气回收率为34.57%，且每天产单位吨氧需吸附剂量为61.18 kg·TPD^-1。

关键词: 吸附, 分离, 制氧, 充压, 数值模拟

CLC Number:

TQ028.1

ZHU Xianqiang, LIU Yingshu, YANG Xiong, LIU Wenhai, LI Yongling. Effect of two-step pressurization with intermediate gas on rapid vacuum pressure swing adsorption process for oxygen generation[J]. CIESC Journal, 2016, 67(10): 4264-4272.

祝显强, 刘应书, 杨雄, 刘文海, 李永玲. 中间气两步充压对快速真空变压吸附制氧的影响[J]. 化工学报, 2016, 67(10): 4264-4272.

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