二氧化碳捕集技术及应用分析

分析了CO2捕集技术及现状。CO2捕集是CCS的关键技术单元之一,针对不同的CO2气源,国内外研究开发了多种技术。许多CO2捕集技术已经工业化,其中燃烧后烟气中CO2的捕集技术主要是以一乙醇胺(MEA)为基础的胺法;燃烧前的CO2捕集技术主要应用于IGCC电厂,一般需要对煤气中CO进行部分变换,变换后脱碳可采用成熟技术,如Selexol(NHD)等。富氧燃烧则是在中试成功的基础上,进行更大规模的工业示范。国内外大型煤制油化工项目主要采用低温甲醇洗脱除CO2,如果设置CO2产品塔,则可以获得体积分数98%以上的CO2。天然气脱碳主要采用MDEA技术。另外还有低温法、PSA、膜分离等CO2捕集技术及化学链燃烧等一些正在研发的技术。     

基于双流化床模型的高温钙基碳捕集流程敏感性分析

介绍了几种碳捕集技术方法,高温钙基循环采用石灰石作为吸附剂,是一种高效的燃烧后二氧化碳捕集技术.利用Aspen Plus软件建立了高温钙基循环捕集工艺模型,优化了碳酸化反应过程工艺参数,得到了以下结论:当碳酸化反应温度为630℃、煅烧反应温度为900℃、F0/FCO2为0.04、气固分离效率为1.0、烟气SO2体积分数...     

固体碳酸盐吸附剂干法捕集二氧化碳实验研究

以负载型固体碳酸盐为吸附剂,采用流化床反应器对烟道气中二氧化碳的捕集进行了研究.测定了不同吸附剂、操作温度和反应时间对吸附效果的影响及吸附剂再生性能.结果表明,吸附剂为负载的固体碳酸钠,在65℃～85℃范围内,吸附时间为4 min～10 min,二氧化碳的脱除率达97.5％,吸附剂经过10次再生后达到稳定状态,可以长期使用.     

二氧化碳捕集技术

据相关资料报道,随着人类对能源需求的不断增加,大量煤炭、石油等化石燃料被开采利用,全球排放出的C02将从2002年的236×10^5kt增加到2030年的380×10^5kt,年平均增长率达1．7％。这期间,我国CO2排放也将净增38．37×10^5kt。以CO2为主的温室气体排放量增加,不仅导致了全球气候急剧恶化,     

湍球塔捕集烟气中低浓度二氧化碳特性

引言全球温度逐步上升已经是个不容否认的事实[1],政府间气候变化专门委员会(IPCC,intergovernmental panel on climate change)《2007年气候变化报告》[2]指出温室效应主要是人类活动造成,而且化石燃料燃烧排放的CO2对温室效应贡献率达到56.5%,因此控制CO2是应对全球趋     

膜分离-变压吸附协同捕集低浓度烟气二氧化碳工艺模拟研究

利用软件PROⅡ和Aspen Adsorption分别模拟协同工艺中膜分离和变压吸附过程,通过引入气体流量修正系数解决气体流量不匹配问题,提高膜-变压吸附协同碳捕集工艺模拟的准确性。案例研究表明,引入流量修正系数解决了协同工艺模拟过程中出现的气体流量不匹配问题,实现了稳态膜分离和动态循环变压吸附过程的耦合。与以往的膜-变压吸附协同工艺模拟方法相比较,更好地识别了能耗降低和捕集率提升的技术途径。     

二氧化碳捕集技术研究进展

结合目前二氧化碳捕集技术的发展现状,对二氧化碳捕集方法进行深入研究,在此基础上,对二氧化碳捕集机理进行深入分析,为推动二氧化碳捕集技术的进一步发展奠定基础。     

碳捕集固体胺吸附剂载体性能优化策略及分析

碳捕集是“双碳”下推动化石能源低碳应用的有效途径,固体胺吸附剂是实现碳捕集、利用与封存的重要手段。其中,载体改性和胺种类优化是固体胺吸附剂研究热点策略。综述和评论了国内外固体胺吸附剂优化策略的作用机制、技术难点和碳捕集效果等,重点阐述并比较了硅基、多孔碳和有机框架载体优化策略在改善CO2选择性、吸附容量和稳定性等方面的作用,展望了固体胺吸附剂未来在高效稳定捕集、生物质吸附和碳利用与封存等研究方向和应用前景。     

低分压CO2回收新技术捕集燃煤电厂烟气CO2

基于分子模拟和设计,开发了以一乙醇胺(MEA)为主溶剂,优选添加了活性胺、抗氧化剂和缓蚀剂组成了适用于回收低分压CO2的优良复合吸收剂,在华能北京热电厂建立了我国第1套燃煤电站烟气CO2捕集示范装置,并完成了运行测试。结果表明:CO2回收装置出来的CO2纯度为99.5%(体积分数),每tCO2蒸汽消耗为3.5GJ,每tCO2溶液消耗小于1.5kg。该套装置的建成和各项指标试验的进行将为我国大规模推广电站CO2捕集奠定基础。     

CO2捕集技术的研究进展

介绍了近年来二氧化碳捕集技术路线和国内外的有关研究项目,分析了各种方法的分离原理及优缺点。并对二氧化碳捕捉技术发展前景进行了展望。     

Synthetic Ca‐based solid sorbents suitable for capturing CO2 in a fluidized bed

Coprecipitation and hydrolysis of CaO have been employed to produce Ca‐based synthetic sorbents suitable for capturing CO₂ in a fluidized bed. Their composition, CO₂ uptake, volume in small pores (2–200 nm) and resistance to attrition were measured and compared to those of limestone and dolomite. Sorbents produced by hydrolysis showed the highest uptake and resistance to attrition. After 20 cycles of carbonation and calcination, two sorbents exceeded the uptake of both limestone and dolomite, when subjected to the same regimes of reaction. A sorbent's uptake of CO₂ was shown to be determined by the volume in pores narrower than ～200 nm.     

胺基CO2固体吸附剂脱碳特性及SO2的影响

燃煤电厂烟气中存在的微量SO₂对胺基CO₂固体吸附剂的碳酸化反应及循环特性有不利影响。利用固定床反应器,针对采用溶胶凝胶法制备的胺基CO₂固体吸附剂的碳酸化特性及其在含SO₂气氛下的失效规律进行了实验研究,并结合红外光谱、有机元素分析、BET等测试手段,研究其失效机理。结果表明,所制备的胺基CO₂固体吸附剂在反应温度50℃时具有较好的碳酸化反应特性和循环特性。当反应气氛中存在SO₂时,由于生成了不可再生的亚硫酸/硫酸盐类物质而导致胺基活性位损失,孔隙结构发生变化,影响了吸附剂的脱碳性能,但适当提高反应温度可提高吸附剂的碳酸化反应竞争性。     

Performance of limestone-based sorbent for sorption-enhanced gasification in dual interconnected fluidized bed reactors

A possibility to carry out sorption-enhanced gasification (SEG) is represented by its integration with the calcium looping concept in dual interconnected fluidized beds (DIFB). This article is focused on the sorbent CO₂ uptake performance and attrition/fragmentation tendency when operating conditions simulating those of a DIFB-SEG process are adopted. Experiments were carried out on a commercial Italian limestone in a laboratory-scale DIFB reactor. Carbonation was carried out in a range of test conditions, including variable temperature (600–700°C) and absence/presence of steam (10% by volume); CO₂ concentration was set at 10% by volume. The characterization is extended by investigating the behavior of preprocessed DIFB-SEG samples on impact fragmentation tests, conducted in an ex situ apparatus. Tests were carried out for impact velocities in the range 17–45 m/s. Results were discussed considering both the impact velocity value and the operating conditions under which the sample was preprocessed in the fluidized bed.     

基于3kW塔式串行流化床差异燃料的化学链燃烧解析

化学链燃烧反应器具有广泛的燃料适应性,可同时兼顾气、液、固多类型燃料的运行。本文依托耦合内构件的3kW塔式串行流化床反应器,分别开展异丙醇、污泥以及煤炭的化学链燃烧实验,探究燃料物化属性对化学链燃烧过程与反应器运行的影响,揭示面向目标燃料的反应器针对性设计、载氧体性能选择与流化操作策略,助力形成指向性强、碳捕集效率高与操作灵活的化学链燃烧技术。面对碳化程度低、有机质含量高的固体燃料,焦炭气化速率已非强化重点,如污泥在3kW塔式反应器910℃与150s停留时间内,可实现大于99%的CO₂捕集效率,化学链燃烧反应器应侧重改善可燃气体转化与旋风分离器对轻质焦炭颗粒的捕捉。当采用异丙醇等高CH₄含量的燃料时,Fe基矿石载氧体的反应性能不足,3kW反应器的额外耗氧率高达10%～19%,其中未燃尽CH₄对额外耗氧率的贡献占比超80%。化学链燃烧反应器需依据热解反应气的物化特性,选择或掺混功能性载氧体,以针对性改善气固转化。在煤等高碳化燃料的化学链燃烧过程中,焦炭气化是反应的限制性步骤,简化循环结构的3kW塔式反应器停留时间不足,仅可...     

吸附法碳捕集固体胺吸附剂成型技术研究进展

吸附法碳捕集技术是实现工业过程或大气中CO₂分离与脱除的重要途径之一,高性能吸附剂的开发是该技术的关键。固体胺吸附剂由于其优异的CO₂吸附量、选择性以及较低的再生能耗,近年来受到了广泛的关注,但用于工业的成型吸附剂仍面临机械强度低、稳定性差和胺流失严重等关键难题,难以在工业中大范围的推广应用。本文分析了固体胺成型吸附剂制备面临的主要难题,重点总结了近年来国内外吸附剂成型技术的研发进展,并对固体胺工业吸附剂的发展方向进行了展望。未来固体胺吸附法碳捕集技术的研发重点在于立足吸附反应机理和工业烟气的特性,创新成型固体胺吸附剂制备技术,提升吸附剂的CO₂吸附量、胺效率、机械与循环稳定性,研发低能耗的配套吸附工艺和核心装置。     

双流化床生物质气化炉研究进展

生物质是重要的清洁可再生能源,双流化床生物质气化技术是将低品位的生物质能转化成高品位氢能的重要途径。本文阐明了双流化床气化过程的基本原理,从燃气中氢气浓度、焦油含量和装置热效率等角度,介绍了双流化床生物质气化技术的早期探索和发展现状,对目前几种典型双流化床生物质气化炉的炉型设计及相关试验研究进行了分析和总结。指出内循环双流化床气化炉结构虽然简单紧凑,但是难以避免气化室和燃烧室之间的气体串混问题;而外循环流化床通过外置返料器很好地解决了气体串混问题。分析了不同气化室优化设计方案对提升燃气品质的理论依据及其优缺点。最后对双流化床生物质气化技术的发展进行了总结和展望,指出双流化床生物质气化制氢具有非常广阔的工业化应用和发展前景。     

Mathematical modeling of a moving bed reactor for post‐combustion CO2 capture

A mathematical model for a moving bed reactor with embedded heat exchanger has been developed for application to solid sorbent‐based capture of carbon dioxide from flue gas emitted by coal‐fired power plants. The reactor model is one‐dimensional, non‐isothermal, and pressure‐driven. The two‐phase (gas and solids) model includes rigorous kinetics and heat and mass transfer between the two phases. Flow characteristics of the gas and solids in the moving bed are obtained by analogy with correlations for fixed and fluidized bed systems. From the steady‐state perspective, this work presents the impact of key design variables that can be used for optimization. From the dynamic perspective, the article shows transient profiles of key outputs that should be taken into account while designing an effective control system. In addition, the article also presents performance of a model predictive controller for the moving bed regenerator under process constraints. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3899–3914, 2016     

Numerical simulations and comparative analysis of two- and three-dimensional circulating fluidized bed reactors for CO2 capture

Carbon dioxide (CO₂), the main gas emitted from fossil burning, is the primary contributor to global warming. Circulating fluidized bed reactor (CFBR) is proved as an energy-efficient method for post-combustion CO₂ capture. The numerical simulation by computational fluid dynamics (CFD) is believed as a promising tool to study CO₂ adsorption process in CFBR. Although three-dimensional (3D) simulations were proved to have better predicting performance with the experimental results, two-dimensional (2D) simulations have been widely reported for qualitative and quantitative studies on gas–solid behavior in CFBR for its higher computational efficiency recently. However, the discrepancies between 2D and 3D simulations have rarely been evaluated by detailed study. Considering that the differences between the 2D and 3D simulations will vary substantially with the changes of independent operating conditions, it is beneficial to lower computational costs to clarify the effects of dimensionality on the numerical CO₂ adsorption runs under various operating conditions. In this work, the comparative analysis for CO₂ adsorption in 2D and 3D simulations was conducted to enlighten the effects of dimensionality on the hydrodynamics and reaction behaviors, in which the separation rate, species distribution and hydrodynamic characteristics were comparatively studied for both model frames. With both accuracy and computational costs considered, the viable suggestions were provided in selecting appropriate model frame for the studies on optimization of operating conditions, which directly affect the capture and energy efficiencies of cyclic CO₂ capture process in CFBR.     

煤/生物质流态化富氧燃烧的CO2富集特性

流化床富氧燃烧是具有重要应用前景的燃烧中碳捕集技术。为更深入认识固体燃料的流态化富氧燃烧行为,构建了微型流态化反应-质谱联用实验系统,反应器直径10 mm,燃烧温度700～900℃,探索了基于在线质谱分析的流态化燃烧过程特性表征方法,以烟煤和花梨木为对象,研究了煤、生物质及其混合物在富氧气氛和流态化条件下的燃烧行为,重点考察了氧浓度、燃烧温度、煤与生物质质量比对CO₂谱峰曲线形态、反应总时间、起始反应时刻、烟气中富集CO₂体积分数、颗粒燃烧产生CO₂量、CO₂相对生成率等特性的影响。结果表明,在O₂/CO₂燃烧气氛下,随着氧体积分数增加,燃烧总反应时间缩短,颗粒燃烧产生的CO₂量和生成速率均增加,但烟气中富集的CO₂体积分数减小;提高燃烧温度,缩短了燃烧过程所需的时间,可以促进CO₂的富集,烟气中CO₂浓度、颗粒燃烧产生的CO₂量和生成速率均增加;生物质比例增大,起始反应时间提前,燃烧反应所需总时间减少,烟气中富集的CO₂浓度和颗粒燃烧产生的CO₂均减少,但CO₂生成速率增加。