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。     

变压吸附(PSA)空分制氧技术进展

论述了 PSA法空分制氧分子筛的开发现状和制氧工艺的进展 ,为 PSA法空分制氧今后的发展提出了研究方向     

均压方式对微型变压吸附制氧装置的影响

采用两塔变压吸附制氧实验装置研究了上下均压、交叉均压、下均压、上均压等4种方式对制氧效果和能耗的影响。结果表明,采用均压方式制氧能提高制氧效果,上均压方式、上下均压方式能显著提高排氧浓度,且最高排气O2质量分数超过90%;采用均压方式制氧节能效果明显,上均压方式、上下均压方式制氧的能耗较低,节能率达30%以上。     

Production of Hydrogen and Ammonia Synthesis Gas by Pressure Swing Adsorption

Abstract

Two new pressure swing adsorption processes for the simultaneous production of hydrogen or ammonia synthesis gas and carbon dioxide from a reformer off-gas feed are described. Both products are produced at high purity and recovery. Performance data for these processes are reported.     

变压吸附原理在工业制氢中的运用

变压吸附(PSA)是一种新型的气体吸附分离技术,目前在工业制氢中的应用非常广泛。选取的氢源是130 000m~3/h的半焦煤气,其φ(H_2)30%,具体讨论PSA原理在半焦煤气制氢工作中的运用,目的是分离制取纯度较高的H_2。     

变压吸附制氧在玻璃纤维行业纯氧燃烧的经济性分析

介绍了玻璃纤维行业的基本情况和纯氧燃烧技术,对深冷空分和变压吸附制氧技术做了对比分析.概述了变压吸附制氧由于其工艺简单、能耗较低、操作灵活、安全性较高、维护方便等优势在玻纤池窑纯氧燃烧工艺选型上逐渐占有重要地位.同时对变压吸附制氧的发展、工艺原理以及特点做了简要分析.     

变压吸附的实质

变压吸附是利用分子筛筛分机理的特性来实现气体分离的。由于分子运动自由程的不同,气体分子通过分子筛的孔向孔内扩散时所受阻力不同,导致在孔内扩散速率不同,宏观上这种分离体现为气体被固定于分子筛的孔内部被"吸附"。实际操作时,不断采取"加压吸附-减压脱附"循环方式,因此被形象地称为"变压吸附",其实质是基于分子筛孔本身的筛分机理,并非吸附机理。通过变压吸附的机理分析,我们确定了分子筛孔径的选择方法,同时分析了变压吸附过程的影响因素。     

变压吸附制纯氧过程阀系数的优化控制

利用电路网络模型,对变压吸附制纯氧阀系数进行优化控制,在碳分子筛为第一级吸附,5A分子筛作为二级吸附工艺中,可得到浓度为99.06%,回收率为28.4%的氧气产品,从而提高了氧气的回收率,增加了单位吸附剂的生产能力,节省了动力消耗.     

Syngas Stoichiometric Adjustment for Methanol Production and Co-Capture of Carbon Dioxide by Pressure Swing Adsorption

Methanol is an important raw material in industry and is commonly produced from syngas. The stoichiometric ratio (H₂–CO₂)/(CO + CO₂) of the methanol synthesis reactor feed stream must be adjusted to approximately 2.1. In this study, the replacement of the solvent unit within a coal to methanol process by a pressure swing adsorption (PSA) unit is proposed. The PSA produces a hydrogen enriched stream, to adjust the stoichiometric ratio of the methanol feed stream, and simultaneously captures the carbon dioxide for future sequestration. The feed flow rate is sub divided into eight 4-bed PSA units, operated with a defined phase lag between them in order to flatten the products (composition and flow rate) oscillations. The results show that the stoichiometric adjustment is possible and that oscillations on the products flow rate and composition are reduced to less than 3%. A carbon dioxide stream of 95.15% is obtained with a recovery of 94.2% and a productivity of 82.7 mol CO₂/kg/day. The power consumption of the global process is 119.7 MW, which includes the requirements for the rinse stream (64.4 MW) and the compression of the CO₂ product to 110 bar for sequestration (55.3 MW).     

Simultaneous Production of Hydrogen and Carbon Dioxide from Steam Reformer Off-Gas by Pressure Swing Adsorption

Abstract

Pressure swing adsorption (PSA) processes are used for the production of ultrapure hydrogen from a crude hydrogen stream containing H₂O, CO₂, CO, CH₄, and N₂ impurities which is produced by steam reformation of natural gas or naphtha. Two commercial PSA processes designed for this purpose are reviewed and a new commercial PSA process which simultaneously produces ultrapure hydrogen and high purity carbon dioxide products from the crude hydrogen with high recoveries of both components is described. Performance data for the new process are reported.     

变压吸附过程的数学模拟

变压吸附过程的数学模拟崔群姚虎卿（南京化工大学，南京２１０００９）关键词变压吸附（ＰＳＡ）数学模拟１前言变压吸附过程具有常温操作、易于自控、可获得高纯度产品等特点。广泛用于炼油和石油化工过程尾气的回收等系统，如用于炼油厂放空气和合成氨厂弛放气的Ｈ２...     

Predictive Dynamic Model of Air Separation by Pressure Swing Adsorption

A general dynamic model is developed for separation of air over a carbon molecular sieve and a zeolite adsorbent for production of nitrogen and oxygen. The proposed model is validated using experimental data from working laboratory scale N₂–PSA and laboratory scale O₂–PSA systems. Simulations studies are performed to investigate the effect of changing various process variables, such as the duration of PSA steps, bed length and feed inlet velocity.     

变压吸附方法分离五元气体混合物

本文研究了用变压吸附从五元气体混合物分离H_2及操作条件对分离的影响.提出了简化的双孔扩散模型模拟变压吸附过程,计算结果和实验数据符合良好.     

Feed Purge Cycles in Pressure Swing Adsorption

Abstract

Three new pressure swing adsorption cycles for the production of oxygen-enriched air at very high recoveries are developed. The cycles involve a purge step using low-pressure feed gas. Local equilibrium theory is used to predict purities and recoveries for air separation with 5A zeolite. Novel methods for drying the inlet air are developed. For low product purities these processes are predicted to have very high recoveries and adsorbent productivities. A simple new method for determining the location of a curved shock wave is illustrated. Other possible applications of PSA feed purge cycles are briefly discussed.     

变压吸附制氢装置扩能改造总结

介绍了采用改良变压吸附技术对现有变压吸附（PSA）制氢装置扩能改造的情况。通过改造,装置性能得到了提升,原料气处理能力由16000m^3／h（标态）提高至25000m^3／h（标态）,H2收率提高了约4％,满足了公司用氢要求。本次改造投资较少,工期较短,为公司创造了很好的经济效益。     

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.     

Production of Motor Fuel Grade Alcohol by Concentration Swing Adsorption

Abstract

A new cyclic process concept called “concentration swing adsorption” for separation of bulk binary liquid mixtures is described. The process carries out the primary separation by selective liquid-phase adsorption of one of the components of the feed mixture on an adsorbent. The adsorbed component is then desorbed by a desorbent liquid which is equally or more strongly adsorbed than the slectively adsorbed component of the feed mixture. The desorbent liquid is removed from the adsorbent by displacing it with the less strongly adsorbed component of the feed mixture so that the adsorbent can be resused. The process also includes a complementary step where the adsorbent is rinsed with the more strongly adsorbed component of the feed mixture so that two essentially pure products are produced from the feed mixture with high recoveries of both components. At least one simple distillation is also required by the process which separates the desorbent liquid from the less strongly adsorbed component of the feed mixture. The process can be used to separate liquid mixtures with close boiling components or azeotropic mixtures which require energy intensive distillation. A very efficient separation can be achieved in these cases by spending only a fraction of the distillation energy. An example of such an application, viz., separation of a bulk ethanol–water mixture for motor fuel grade alcohol production, is described. A local equilibrium model of the process is used to evaluate the performance of the process for that separation using an activated carbon as the adsorbent and acetone as the desorbent liquid. Experimentally measured equilibrium adsorption characteristics for ethanol–water, acetone–water, and acetone–ethanol binary liquid mixtures on the carbon as well as adsorption column dynamics for the steps of the process are reported.     

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。     

氢气变压吸附提纯单元改造探讨

中国石油吉林石化公司乙烯厂乙烯装置氢气变压吸附提纯单元(PSA单元)是与原300kt/a乙烯装置一同开车的单元,设计能力和吸附组分完全按照原300kt/a装置所产生氢气产量和组分而确定。装置700kt/a改扩建完成后,氢气产量和组分发生了很大变化,同时,PSA单元所存在的尾氢流量波动过大问题一直是制约裂解炉炉温控制的瓶颈。因此,2008年对PSA单元进行技术改造,使其处理能力和尾氢运行平稳率得到明显提高。