共查询到19条相似文献,搜索用时 93 毫秒
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燃烧后CO2捕集技术(PCC)因易于与既有电厂结合而被认为是一项减少二氧化碳排放的重要技术。化学吸收、吸附和膜分离是PCC的主流技术。在CO2吸附技术类中,变温吸附(TSA)是一种有效的吸附方法。近年来,TSA技术的能源消耗和能源转换效率问题成为人们对其大规模部署的关注焦点。然而,大多数的研究都是将数学模型和仿真方法应用于TSA的性能评估,缺乏足够的实验研究支持。为了对TSA系统的能源转化效率进行实验分析,开发了一套四步法TSA系统,能效性能是基本分离性能外的主要考察指标。实验采用沸石13X-APG作为吸附剂材料,根据实验测得的两组吸附等温线,计算了CO2/N2的吸附选择性系数。通过进气CO2浓度、解吸时间、吸附温度和解吸温度对纯度、回收率、单位能耗和第二定律效率的影响分析,得到了4组实验结果。结果表明,第二定律效率的范围为3.24%~9.23%,回收率和纯度最高分别为83.97%和94.70%。解吸温度和进气CO2浓度的升高,吸附温度的降低有利于分离及能效性能提升。延长解吸时间有利于分离和能效提升,但过长的操作时间反而使得效果变差,这会对工程中的运行策略优化产生积极的指导意义。 相似文献
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变温吸附(TSA)碳捕集技术是控制碳排放进而实现“双碳”目标的有效保障手段之一。然而,由于目前缺乏相对完善的计量体系和可执行的标准化测试方案,导致机组性能的测试结果差别较大,缺乏规律性所造成的趋势和性能迭代困难不利于TSA产业化发展。本文初步提出了包含测试工况、性能评价指标、数据的测量与采集三个方面的标准化测试方案,并对样机规模的实物机组进行了性能测试。结果表明,该套方案的可执行度高,可为相关机组的性能评价工作提供借鉴。此外,机组的性能测试结果显示,该机组的运行状态容易控制,纯度和回收率最高均能达到90%以上,但是能源效率在3.5%~6.5%之间,提升潜力大。对标分析发现机组内的管道等部件损失的能耗占比30%~40%,所以需要通过优化管道线路布置、提高吸附腔内换热效率、优化解吸温度和真空压力等运行参数等方式来进一步降耗提效。 相似文献
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采用13X-APG沸石吸附捕集烟道气中CO2,并研发了五步循环真空变压变温(VTSA)耦合吸附捕集工艺. 实验测定了循环吸附/解吸过程中吸附剂再生率、烟道气中CO2回收率、产品气量及产品气中CO2纯度,并与传统的真空变压吸附工艺(VSA)和变温吸附工艺(TSA)比较. 由于VTSA在真空解吸的同时加热吸附剂,减少了真空泵的电耗,可在较温和的真空下(约3′103 Pa)操作,附加的吸附剂再生温度也不高,90~150℃下吸附剂再生率达97%以上,CO2回收率达98%以上. 吸附剂捕集CO2的量可提高到1.8 mol/kg,是VSA工艺产品气量的2倍,且产品气中CO2纯度提高到90%以上. 相似文献
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通过窑尾CO2变压吸附捕集与利用的成套装置,将窑尾烟气CO2提纯到40%后,巧妙搭载在飞灰水洗水泥窑协同处置技术系统中,用于飞灰水洗液硬度降控和pH调节,低成本利用窑尾烟气CO2.同时结合前期装置运行中出现的问题,进行技术优化改进,建成变温吸附(TSA)+变压吸附(PSA)的碳捕集装置一套,该装置CO2吸附速率可达到1... 相似文献
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Modeling of circulating fluidized beds systems for post‐combustion CO2 capture via temperature swing adsorption 下载免费PDF全文
Stefano E. Zanco Marco Mazzotti Matteo Gazzani Matteo C. Romano Isabel Martínez 《American Institute of Chemical Engineers》2018,64(5):1744-1759
The technology of circulating fluidized beds (CFBs) is applied to temperature swing adsorption (TSA) processes for post‐combustion CO2 capture employing a commercial zeolite sorbent. Steady state operation is simulated through a one‐dimensional model, which combines binary adsorption with the CFB dynamics. Both single step and multi‐step arrangements are investigated. Extensive sensitivity analyses are performed varying the operating conditions, in order to assess the influence of the main operational parameters. The results reveal a neat superiority of multi‐step configurations over the standard one, in terms of both separation performance and efficiency. Compared to fixed‐bed TSA systems, CFB TSA features a high compactness degree. However, product purity levels are limited compared to the best performing fixed‐bed processes, and heat management within the system appears to be a major issue. As regards energy efficiency, CFB systems place themselves in between the most established absorption‐based technologies and the fixed‐bed TSA. © 2017 The Authors AIChE Journal published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers AIChE J, 64: 1744–1759, 2018 相似文献
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Integrated adsorbent‐process optimization for carbon capture and concentration using vacuum swing adsorption cycles 下载免费PDF全文
A novel approach for integrated adsorbent and process design is proposed. The traditional pressure or vacuum swing adsorption (PSA) / vacuum swing adsorption (VSA) process optimization for chosen objectives, where operating conditions are the decision variables, and CO2 purity and recovery are constraints, is expanded to include adsorbent isotherm characteristics as additional decision variables. Two VSA cycles, namely a four‐step process1, currently known to have the lowest energy consumption for CO2 capture and concentration (CCC), and a six‐step process2, recently proven to have a wider operating window for the evacuation pressure, have been investigated in the current study. The integrated optimization results simultaneously provide the lower bound of minimum energy and upper bound of maximum productivity for CCC achievable from the two VSA processes along with the operating conditions and the corresponding isotherm shapes necessary to achieve them. It may be viewed as an enabler for adsorbent design or expedient adsorbent search by process inversion. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2987–2995, 2017 相似文献
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介绍了采用变温吸附技术对氯乙烯进行干燥脱水的工艺流程及运行效果,阐述了变温吸附装置运行过程中出现的问题及相应的解决方法. 相似文献
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为减缓气候变化,减少CO2的排放,对真空变温吸附(TVSA)从干烟道气中捕集CO2进行了系统的研究。以沸石13X为吸附剂,设计了实验室规模的4塔连续进料的TVSA工艺,并建立数学模型进行数值模拟。模拟结果表明,通过四塔TVSA可获得纯度为97.54%,回收率为96.79%的CO2产品气,其产率为1.7 mol· -1·h-1,能耗为3.14 。此外,考察了进料量、循环回流步骤时间、真空度对产品气纯度、回收率、吸附剂产率和工艺能耗的影响,并且分析了塔内压力与温度变化,详细探讨了塔内气固相浓度随轴向的分布。良好的工艺效果表明,TVSA有潜力成为一种能够生产高纯度高回收率的CO2产品气,并具有良好经济效益的捕碳工艺。 相似文献
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An equilibrium theory simulator (Esim) for the simulation of cyclic adsorption processes is presented. The equations are solved with a Godunov upwind flux scheme that does not require either the evaluation of characteristics or shock equations or the imposition of a numerical entropy condition to track shocks. Esim is able to simulate non-trace and non-isothermal adsorption systems with any adsorption isotherm. Esim has been validated against gPROMS based simulations that use the full set of governing equations (including mass and heat transfer resistances and axial dispersion) carried out under conditions close to the limits where equilibrium theory is valid. Esim enables the establishment of bounds for the optimal performance of an equilibrium driven separation and requires only the measurement of adsorption isotherms. 相似文献
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Jianghua Ling Penny Xiao Augustine Ntiamoah Dong Xu Paul Webley Yuchun Zhai 《中国化学工程学报》2016,24(4):460-467
Different VSA(Vacuum Swing Adsorption) cycles and process schemes have been evaluated to find suitable process configurations for effectively separating CO2 from flue gases from different industrial sectors. The cycles were studied using an adsorption simulator developed in our research group, which has been successfully used to predict experimental results over several years. Commercial zeolite APGIII and granular activated carbon were used as the adsorbents. Three-bed VSA cycles with- and without-product purge and 2-stage VSA systems have been investigated. It was found that for a feed gas containing 15% CO2(representing flue gas from power plants), high CO2 purities and recoveries could be obtained using a three-bed zeolite APGIII VSA unit for one stage capture, but with more stringent conditions such as deeper vacuum pressures of 1–3 k Pa. 2-stage VSA process operated in series allowed us to use simple process steps and operate at more realistic vacuum pressures. With a vacuum pressure of 10 k Pa, final CO2 purity of 95.3% with a recovery of 98.2% were obtained at specific power consumption of 0.55 MJ·(kg CO2)-1from feed gas containing15% CO2. These numbers compare very well with those obtained from a single stage process operating at1 k Pa vacuum pressure. The feed CO2 concentration was very influential in determining the desorption pressure necessary to achieve high separation efficiency. For feed gases containing N 30% CO2, a singlestage VSA capture process operating at moderate vacuum pressure and without a product purge, can achieve very high product purities and recoveries. 相似文献
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介绍了采用新型吸附剂及变温变压吸附技术脱除氯乙烯单体中水分的原理及工艺流程。该技术用于20万t/a氯乙烯单体装置的深度脱水处理后,氯乙烯单体的含水质量分数由700μg/g下降到20~50μg/g。该技术脱水能力强、效率高,生产过程中无"三废"排放。 相似文献
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The role of water on postcombustion CO2 capture by vacuum swing adsorption: Bed layering and purge to feed ratio 下载免费PDF全文
Gang Li Penny Xiao Jun Zhang Paul A. Webley Dong Xu 《American Institute of Chemical Engineers》2014,60(2):673-689
The influence of water vapor on the adsorption of CO2 in carbon capture by vacuum swing adsorption (VSA) was described. VSA experiments with single and multilayered columns using alumina and zeolite 13X were conducted to understand the migration of water. The penetration depth of water in the column could be controlled by maintaining the purge‐to‐feed ratio above a critical value. At high water content in the feed (>4%), employment of a water adsorbing prelayer was essential to prevent failure of the carbon capture process. A simple axial working capacity model predicts the penetration depth of water in the column for a given feed temperature and adsorption isotherm, and the layering ratio can be selected accordingly. Although water is detrimental to CO2 capture with polar adsorbents, long‐term recovery of CO2 is still possible by appropriate layering and ensuring an adequate purge‐to‐feed ratio. © 2013 American Institute of Chemical Engineers AIChE J 60: 673–689, 2014 相似文献