Influence of product flow rate on O<sub>2</sub> volume fraction in PSA oxygen generation process

LIU Ying-shu; ZHANG Quan-li; LIU Wen-hai; LI Zi-yi; YANG Xiong; CAO Xi-guang; FU Yao-guo; LI Ye

doi:10.13374/j.issn2095-9389.2019.11.11.002

Volume 42 Issue 11

Nov. 2020

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Article Navigation > Chinese Journal of Engineering > 2020 > 42(11): 1507-1515

LIU Ying-shu, ZHANG Quan-li, LIU Wen-hai, LI Zi-yi, YANG Xiong, CAO Xi-guang, FU Yao-guo, LI Ye. Influence of product flow rate on O2 volume fraction in PSA oxygen generation process[J]. Chinese Journal of Engineering, 2020, 42(11): 1507-1515. doi: 10.13374/j.issn2095-9389.2019.11.11.002

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LIU Ying-shu, ZHANG Quan-li, LIU Wen-hai, LI Zi-yi, YANG Xiong, CAO Xi-guang, FU Yao-guo, LI Ye. Influence of product flow rate on O₂ volume fraction in PSA oxygen generation process[J]. Chinese Journal of Engineering, 2020, 42(11): 1507-1515. doi: 10.13374/j.issn2095-9389.2019.11.11.002

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Influence of product flow rate on O₂ volume fraction in PSA oxygen generation process

doi: 10.13374/j.issn2095-9389.2019.11.11.002

School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China

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Corresponding author: E-mail: ziyili@ustb.edu.cn
Received Date: 2019-11-11
Publish Date: 2020-11-25

Abstract

Abstract

In recent decades, the small-scale pressure swing adsorption (PSA) oxygen generator has been widely used in the fields of home medical and hospital oxygen supply, anoxic environments, and plateau environments due to its cost effectiveness, operational flexibility, and adequate O₂ volume fraction. The flexible optimization of PSA oxygen generation in response to changes in product demand is an important factor in its practical performance. To study the influence of a variable product flow rate on O₂ volume fraction in the small-scale PSA oxygen generator, experimental equipment was set up, which consisted of a modified Skarstrom-cycle two-bed PSA system. The research results show that variations in the parameters at the lower product flow rate (≤10.37 L·min^?1) may have a negative effect on oxygen countercurrent mixing, which can impair oxygen generation, and at higher product flow rates (≥13.57 L·min^?1) may cause the negative effect of nitrogen breakthrough, which decreases the working capacity of the adsorbents in the bed. The O₂ volume fraction at the lower product flow rate was improved by increasing the ratio of total oxygen in the purge gas to the total oxygen in the feed gas (P/F) and by decreasing the ratio of the highest adsorption pressure to the lowest desorption pressure (θ) during a cycle to suppress oxygen countercurrent mixing. The O₂ volume fraction at the higher product flow rate was improved by increasing the P/F and θ values to improve the working capacity of the adsorbents in the bed. Accordingly, adjustments are made in the P/F and θ values at the lower and higher product flow rates to achieve optimal oxygen generation performances, enhancing the O₂ volume fraction from 92.4% and 74.0% to 95.7% and 74.9% at the respective product flow rates of 3.55 L·min^?1 and 19.88 L·min^?1. This work is meaningful for the optimization of the parameters of the PSA oxygen production process at variable product flow rates.
- pressure swing adsorption (PSA),
- product flow rate,
- oxygen countercurrent mixing,
- parameter adjustment,
- O₂ volume fraction

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References(23)

References

[1]	Yang X, Epiepang F E, Li J B, et al. Sr-LSX zeolite for air separation. Chem Eng J, 2019, 362: 482 doi: 10.1016/j.cej.2019.01.066
[2]	冉莊, 羅勇軍. 高原制氧供氧技術及合理用氧研究進展. 人民軍醫, 2019, 62(5):466 Ran Z, Luo Y J. Research progress on oxygen production and supply technology and rational use of oxygen in plateau. People’s Military Surgeon, 2019, 62(5): 466
[3]	劉應書, 祝顯強, 曹永正, 等. 彌散供氧流動特性及其富氧效果. 工程科學學報, 2015, 37(10):1370 Liu Y S, Zhu X Q, Cao Y Z, et al. Flow characteristics and oxygen-enriched effect of oxygen diffusion. Chin J Eng, 2015, 37(10): 1370
[4]	Yang X, Wang H Y, Chen J W, et al. Two-dimensional modeling of pressure swing adsorption (PSA) oxygen generation with radial-flow adsorber. Appl Sci, 2019, 9(6): 1153 doi: 10.3390/app9061153
[5]	Wang Y Y, An Y X, Ding Z Y, et al. Integrated VPSA processes for air separation based on dual reflux configuration. Ind Eng Chem Res, 2019, 58: 6562
[6]	王浩宇, 劉應書, 施紹松, 等. 徑向流吸附器內部結構對變壓吸附制氧效果的影響. 工程科學學報, 2015, 37(2):238 Wang H Y, Liu Y S, Shi S S, et al. Influence of the structure of radial flow adsorbers on oxygen production with pressure swing adsorption. Chin J Eng, 2015, 37(2): 238
[7]	Mendes A M M, Costa C A V, Rodrigues A E. Oxygen separation from air by PSA: modelling and experimental results Part I: isothermal operation. Sep Purif Technol, 2001, 24(1-2): 173 doi: 10.1016/S1383-5866(00)00227-6
[8]	呂愛會, 鄧橙, 朱孟府, 等. 小型變壓吸附制氧工藝技術研究. 應用化工, 2018, 47(3):481 doi: 10.3969/j.issn.1671-3206.2018.03.015 Lü A H, Deng C, Zhu M F, et al. Study on the process of small-scale PSA oxygen generation. Appl Chem Ind, 2018, 47(3): 481 doi: 10.3969/j.issn.1671-3206.2018.03.015
[9]	Farooq S, Ruthven D M, Boniface H A. Numerical simulation of a pressure swing adsorption oxygen unit. Chem Eng Sci, 1989, 44(12): 2809 doi: 10.1016/0009-2509(89)85090-0
[10]	翟暉, 劉應書, 張輝, 等. 小型變壓吸附制氧的真空解吸實驗. 化工進展, 2008, 27(7):1061 doi: 10.3321/j.issn:1000-6613.2008.07.020 Zhai H, Liu Y S, Zhang H, et al. Experimental study on vacuum-desorption of small-scale oxygen concentrator by pressure swing adsorption. Chem Ind Eng Prog, 2008, 27(7): 1061 doi: 10.3321/j.issn:1000-6613.2008.07.020
[11]	Bhat A A, Mang H, Rajkumar S, et al. On-board oxygen generation using high performance molecular sieve. Life Sci J, 2017, 2(4): 380
[12]	章新波, 劉應書, 劉文海, 等. 多塔變壓吸附制氧技術實驗. 低溫工程, 2009(2):43 doi: 10.3969/j.issn.1000-6516.2009.02.010 Zhang X B, Liu Y S, Liu W H, et al. Experiment study on a multicolumn PSA oxygen system. Cryogenics, 2009(2): 43 doi: 10.3969/j.issn.1000-6516.2009.02.010
[13]	Liow J L, Kenney C N. The backfill cycle of the pressure swing adsorption process. AIChE J, 1990, 36(1): 53 doi: 10.1002/aic.690360108
[14]	Mofarahi M, Towfighi J, Fathi L. Oxygen separation from air by four-bed pressure swing adsorption. Ind Eng Chem Res, 2009, 48(11): 5439 doi: 10.1021/ie801805k
[15]	呂愛會, 鄧橙, 朱孟府, 等. 響應面法分析高原環境變壓吸附制氧工藝的研究. 應用化工, 2018, 47(6):1175 doi: 10.3969/j.issn.1671-3206.2018.06.024 Lü A H, Deng C, Zhu M F, et al. Analyzing the PSA process of oxygen generation in plateau environment using response surface method. Appl Chem Ind, 2018, 47(6): 1175 doi: 10.3969/j.issn.1671-3206.2018.06.024
[16]	Tian C X, Fu Q, Ding Z Y, et al. Experiment and simulation study of a dual-reflux pressure swing adsorption process for separating N₂/O₂. Sep Purif Technol, 2017, 189: 54 doi: 10.1016/j.seppur.2017.06.041
[17]	Rege S U, Yang R T. Limits for air separation by adsorption with LiX zeolite. Ind Eng Chem Res, 1997, 36(12): 5358 doi: 10.1021/ie9705214
[18]	Reynolds S P, Ebner A D, Ritter J A. Enriching PSA cycle for the production of nitrogen from air. Ind Eng Chem Res, 2006, 45(9): 3256 doi: 10.1021/ie0513550
[19]	田濤, 劉冰, 石梅生, 等. 雙塔微型變壓吸附制氧機實驗和模擬. 化工學報, 2019, 70(3):969 Tian T, Liu B, Shi M S, et al. Experiment and simulation of PSA process for small oxygen generator with two adsorption beds. CIESC J, 2019, 70(3): 969
[20]	Serbezov A. Effect of the process parameters on the length of the mass transfer zone during product withdrawal in pressure swing adsorption cycles. Chem Eng Sci, 2001, 56(15): 4673 doi: 10.1016/S0009-2509(01)00121-X
[21]	Tondeur D, Chlendi M. Front analysis and cycle policy in PSA operations. Gas Sep Purif, 1993, 7(2): 105 doi: 10.1016/0950-4214(93)85007-I
[22]	Mohammadi N, Hossain M I, Ebner A D, et al. New pressure swing adsorption cycle schedules for producing high-purity oxygen using carbon molecular sieve. Ind Eng Chem Res, 2016, 55(40): 10758 doi: 10.1021/acs.iecr.6b02570
[23]	王浩宇, 劉應書, 張傳釗, 等. π型向心徑向流吸附器變質量流動特性研究. 化工學報, 2019, 70(9):3385 Wang H Y, Liu Y S, Zhang C Z, et al. Study on variable mass flow laws in π-shaped centripetal radial flow adsorber. CIESC J, 2019, 70(9): 3385