Separation of Hydrogen-Lean Mixtures for a High-Purity Hydrogen by Vacuum Swing Adsorption

Abstract

High-purity hydrogen is commercially produced by pressure swing adsorption from hydrogen-rich mixtures. In this work, a vacuum pressure swing adsorption cycle is used to produce high purity hydrogen from a hydrogen-lean binary mixture (20/80 H₂/CO) using zeolite 5A as the sorbent. The effects of different process variables on separation performance have been studied. The purity of hydrogen product increases at low throughput, high feed pressure, high end pressure of cocurrent depressurization, low end pressure of countercurrent evacuation, and short cycle time. Also, it was found that for a H₂-lean mixture, the separation is improved at higher ambient temperature. In addition, a new “vacuum purge” step was found to improve the separation and is therefore a promising step for commercial application.     

气体分离用变压吸附剂的研究进展

介绍了在应用变压吸附生产N2、O2和CO2的生产过程中,沸石分子筛和碳分子筛的吸附分离机理及它们的改性研究,并讨论了国内外目前使用的沸石分子筛和碳分子筛的优缺点,评述了现阶段国内外变压吸附剂的研究现状,进而展望了变压吸附剂的研究和发展趋势。     

Concentration-Thermal Swing Adsorption Process for Separation of Bulk Liquid Mixtures

Abstract

A novel concentration-thermal swing adsorption process is described for separation of bulk binary liquid mixtures. The process is designed to produce essentially two pure products with high recoveries of both components. It is particularly suited for separation of azeotropic or close-boiling liquid mixtures which are difficult to separate by distillation. An example of the performance of the new process for separation of an azeotropic water-methyl acetate mixture is given. Experimental binary surface excess equilibrium isotherms, adsorptive mass transfer coefficients, and column dynamics for adsorption of water-methyl acetate mixtures on NaX zeolite are reported.     

变压吸附空分制氧的技术进展

介绍了近年来变压吸附空分制氧的技术进展情况,分别从空分制氧的工艺和吸附剂的改进状况进行了详细论述,并简单的描述了空分制氧的发展前景。     

Vacuum Pressure Swing Adsorption to Produce Polymer-Grade Propylene

We have evaluated the Vacuum Pressure Swing Adsorption (VPSA) technology to separate propane–propylene streams to produce polymer-grade propylene. Zeolite 4A is used as kinetic adsorbent since propylene diffuses much faster than propane. A single VPSA process is able to produce propylene with purity higher than 99.6%. However, propylene recovery is only 67% and therefore a second stage is used. In this VPSA unit, zeolite 4A with smaller crystal radius is employed to reduce kinetic limitations. The second VPSA (tail unit) produces purified propane and recovers propylene that is recycled to the feed of the first VPSA (front unit). Linking these two VPSA units allows us to produce polymer-grade propylene (PGP) recovering 95.9% of the propylene. Comparing the performance of this process with distillation, there is a significant decrease in the separation volume. However, further efforts are necessary to reduce the power consumption of VPSA which is still slightly higher than for distillation.     

变压吸附分离技术的研究进展

简述了变压吸附技术在分离净化方面的应用,及其在分离提纯高沸点组分中的研究进展,寻求进一步拓展变压吸附技术的应用领域,开发新型工业装置的途径     

介绍一种新的制氮方法——变压吸附制氮

本文介绍了可以代替深冷法的新的制氮方法—变压吸附法,该法适合于70t/d以下规模。该法启动快,可根据需要随意开停车。产品氮气的纯度可达99.5％以上。     

膜分离技术与变压吸附技术结合制取高浓度氧的研究

针对膜分离(MS)技术与变压吸附(PSA)技术在以空气为原料制氧方面各自存在的优缺点,尝试将二者相结合用于制取高浓度(体积分数》99.5%)氧气.通过实验证明了采用MS-PSA流程用于制取高浓度氧是行不通的.而通过PSA-MS流程可得到体积分数为99.51%的氧气.结合实验数据进行模拟计算,得出了PSA-MS制高浓度氧最佳结合点.     

变压吸附气体分离技术应用及展望窥探

为了深入探究变压吸附气体分离技术,分析了技术工作原理,依据此原理,研究此项技术在H_2、CO_2、C0、氯乙烯精馏尾气的回收与提取中的应用方法,并探究参数指标变化下气体回收与提取纯度的影响。基于变压吸附技术应用现状,气体吸附提取纯度仍有上升空间,具有较高的研发应用前景。     

Separation of a Five-Component Gas Mixture by Pressure Swing Adsorption

Abstract

Bulk separation of a five-component mixture simulating coal gasification products was performed by pressure swing adsorption (PSA) using activated carbon. The PSA cycle consisted of four commercially used steps: (I) pressurization with H₂, (II) adsorption, (III) blowdown, and (IV) evacuation. Using this cycle, four products were obtained with a single PSA unit: H₂ (over 99.7% purity), CO, CH₄, and acid gas (CO₂ + H₂S). The first three products contained less than 0.001% H₂S, and the acid gas was suitable for sulfur recovery. A mathematical model incorporating equilibrium adsorption of mixture and mass transfer resistance (of CO₂) was found capable of simulating all steps of the PSA cycle. The model simulation results were in fair agreement with the experimental data. A fundamental understanding of the dynamics of the cyclic process was gained through the model.     

变压精馏分离异丙醇-二异丙醚工艺模拟

在分析异丙醇-二异丙醚二元物系性质的基础上,提出了,采用变压精馏分离该二元混合物系的工艺。利用ASPENPLUS模拟软件．选择NRTL物性模型对该物系的分离工艺进行模拟与参数优化,得到了分离该二元物系的最佳工艺参数。研究表明,采用变压精馏的工艺完全能够达到分离该共沸物的要求,变压精馏是分离提纯该二元共沸物的一种可行方法...     

变压吸附技术在气体分离提纯中的应用

介绍了变压吸附技术的基本原理、发展概况及基本工作过程,并阐述了该技术在氢气的分离与提纯、二氧化碳的分离与提纯、一氧化碳的分离、空气分离制氧、空气分离制氮、碳的脱除等工业过程中的应用,对变压吸附技术今后的发展提出了展望。     

变压吸附分离提纯CO_2技术的应用

本文叙述了变压吸附提纯ＣＯ２技术的基本原理和工艺过程，介绍了我国ＰＳＡ－ＣＯ２的开发过程及发展前景，对已开发的ＰＳＡ－ＣＯ２工业装置的生产成本和经济性进行了分析     

吸附法脱除烷烃中少量芳烃工业可行性分析

在实验研究烷烃中少量芳烃的吸附动态过程的基础上,确定该吸附净化过程的吸附一再生条件,探讨该过程实现的可行性,得到如下结论：从技术性能和技术经济这两个指标出发,对脱除循环烷烃中的少量芳烃的吸附分离过程,用固定床吸附过程来实现比用模拟移动床吸附过程来实现更具可行性,吸附法脱除循环烷烃中的少量芳烃具有设备投资少,能耗低的特点,有可能成为一种替代现行脱除少量芳烃的工艺方法,这些结果为在直链烷基苯的生产过程中,降低循环烷烃中芳构化物的含量,实现延长脱氢催化剂的寿命,提高烷基苯的产量提供了技术基础。     

Separation of Methane and Carbon Dioxide Gas Mixtures by Pressure Swing Adsorption

Abstract

Two pressure swing adsorption processes for separation of methane and carbon dioxide gas mixtures are described. One process simultaneously produces a high purity CH₄ and a high purity CO₂ product with high recoveries of both components from the feed gas. The other process only produces a high purity CH₄ product with high recovery. Test data for these processes are reported and their relative advantages are discussed.     

空气分离过程中的几项有效应用技术

介绍了３２００Ｎｍ＾３／ｈ空分装置设计中采用的几项有效应用技术－分子筛吸附、增压膨胀机、上塔改填料塔等。并对这些技术在空分能耗上的改进作了分析。     

稀土复合吸附剂的制备及变压吸附CO特性的研究

以活性炭负载Cu（I）为原料,添加适量稀土化合物制备成稀土复合吸附剂。实验测定了CO、CO2、CH4、N2在稀土复合吸附剂和5A分子筛上的吸附平衡,考察了CO、N2混合体系在稀土复合吸附剂和5A分子筛上的变压吸附性能。实验结果表明,该吸附剂对CO有很高的选择性,能满足变压吸附的要求,具有工业应用价值。     

变压精馏分离碳酸二甲酯与甲醇工艺流程的模拟

以Wilson模型对碳酸二甲酯与甲醇共沸体系的汽液平衡数据进行了二元交互作用参数的回归,然后以Aspen Plus对常压-加压精馏分离碳酸二甲酯与甲醇的流程进行了模拟与优化,结果表明通过该分离流程可以实现碳酸二甲酯与甲醇的分离,所得碳酸二甲酯与甲醇的质量分数达到99.9%。     

Some Issues in Operating Adsorption Prepurification Systems for Cryogenic Air Separation

Abstract

The paper outlines the operational aspects of a typical prepurification unit associated with a cryogenic air separation plant. The factors which may cause loss of performance are discussed. These include adsorbent degradation, feed impurity levels, moisture ingress, and regeneration aspects. Understanding these factors should improve the efficiency of the system.     

焦炉煤气变压吸附制氢新工艺

变压吸附制氢气体分离技术在工业上得到了广泛应用,已逐步成为一种主要的气体分离技术.本文重点介绍变压吸附技术在焦炉煤气制氢新工艺上的开发与利用,并对变压吸附技术在焦炉煤气实际应用作详细说明.