高温煤气金属脱硫剂的研究进展

煤的清洁转化利用符合中国的能源结构,高温煤气脱硫是提高能源利用率的关键技术。本文综述了单一金属氧化物和复合金属氧化物干法脱除H2S的研究进展,对比分析了单一金属氧化物在脱硫效率、使用温度和再生方面的优缺点,指出由于单一金属氧化物脱硫剂不能满足实际生产需要,因此兼有单一金属氧化物优点的复合金属脱硫剂成为未来研究方向。同时,论述了复合金属脱硫剂的制备原则、脱硫效率及再生等方面的研究状况。在此基础上,重点对铁酸锌和钛酸锌两种具有代表性的复合脱硫剂及其他复合金属脱硫剂进行了介绍。     

高温煤气脱硫剂的研究进展

论述了高温煤气脱硫的重要意义及近几年的研究状况，从高温煤气脱硫剂的发展趋势着重阐述了几种新型的高温煤气脱硫剂的研究状况．以及当前高温煤气脱硫存在的问题，结合我国实际情况对高温煤气脱硫的发展研究提出一些建议，以使在 ＩＧＣＣ研究开发工作中有所突破．     

高温煤气脱硫剂再生行为气氛效应的研究进展

脱硫剂再生过程是高温煤气脱硫工业化应用必备的关键环节之一。本文重点综述了含氧气氛、水气氛、水氧混合气氛和二氧化硫气氛中高温煤气脱硫剂的再生行为。以硫资源化回收作为高温煤气脱硫剂再生的目标,分析了不同再生气氛以及不同再生操作条件对高温煤气脱硫剂再生行为的影响。最后对今后高温煤气脱硫剂的再生研究提出了几点建议。     

高温煤气铁系脱硫剂的研究

高温煤气脱硫净化是目前先进洁净煤利用技术之一 ,但是以前高温煤气脱硫剂在多次硫化再生循环过程中出现粉化 ,妨碍脱硫剂进一步使用 .本研究选择钢厂赤泥作为脱硫剂原料 ,添加不同活性组分和防粉化结构助剂 ,制备了氧化铁基高温煤气脱硫剂 .经过 1 0次硫化 /再生循环实验 .结果表明 :1 0次循环累计 1 96.98% ,再生后脱硫活性不发生变化 ,具有较高和较稳定的脱硫活性 .再生后脱硫剂的机械强度高于新鲜样品 ,在使用过程中没有出现粉化现象 ,这为氧化铁基高温煤气脱硫剂的工业化研究提供了可靠的依据 .     

高温煤气脱硫剂的研究

介绍了高温煤气脱硫剂的研制、脱硫工艺条件试验、再生工艺条件试验和长周期考核试验。结果表明,以锌、锰和铁等氧化物为主成分,辅加多种助剂的高温煤气脱硫剂,可在(350～600)℃脱除煤气中的H_2S和COS,脱硫精度高,硫容大,脱硫剂脱硫后可再生。脱硫剂经22次脱硫-再生循环操作后,仍具有高脱硫性能。     

氧化铈型高温煤气脱硫剂的研究进展

较详尽地叙述了被誉为第二代高温煤气脱硫剂的氧化铈及氧化铈基脱硫剂的研究进展和研究动态.针对目前高温煤气脱硫剂存在的问题,分析了氧化铈及氧化铈基脱硫剂的优点和缺点.指出采用适宜的制备工艺,加入适当的金属氧化物添加剂以大大提高氧化铈的还原性,扩宽脱硫剂的可操作温度范围将是氧化铈基脱硫剂的未来研究开发方向.     

国内外高温煤气脱硫技术探讨

本文从高温脱硫剂、脱硫温区、过程模型化、反应器等方面综述了美、日等发达国家从事高温煤气脱硫的研究概况。结合我国实际,提出了对我国发展高温煤气脱硫技术的看法     

炭基锌锰铜煤气脱硫剂的硫化行为研究

对锌、锰、铜摹单金属和复合金属氧化物脱硫剂的脱硫性能进行了讨论,并对炭材料作为脱硫剂和载体的研究现状进行了分析,同时对活化半焦作为脱硫剂载体的可行性进行了探讨.认为复合金属氧化物脱硫剂能够发挥单氧化物的优势,并克服其不足.将复合金属氧化物负载于炭材料上,可提高金属氧化物活性组分的利用率,改善脱硫剂的硫化性能,同时降低脱硫剂成本,使炭基锌锰铜复合金属氧化物煤气脱硫剂具有广阔的应用前景.     

高温煤气脱硫剂及再生特性研究

高温煤气净化是实现IGCC过程的关键环节，系统地介绍了国内外钙、锌、铜的锰系高温脱硫剂近年来的研究结果，同时结合脱硫剂再生的研究，分析了各种脱硫剂在高温脱硫过程中可能遇到的问题，探讨了各种脱硫剂的再生方法以及相应的尾气处理方案，最后对我国今后高温煤气脱硫剂研究开发提出了几点建议。     

高温煤气脱硫的动力学研究现状及进展

煤气的高温脱硫是洁净煤技术研究和开发的关键技术之一。综述了近年来高温煤气脱硫动力学方面的研究进展,比较分析了目前研究较多的未反应收缩核模型、粒子反应模型和等效粒子模型等动力学模型,认为等效粒子模型综合了未反应收缩核模型和粒子反应模型的优点,能够较好地模拟金属基高温煤气脱硫剂在高温脱硫过程中的动力学行为。详细总结了动力学模型在高温煤气脱硫中的应用。     

煤气净化中H2S干法脱除的研究进展

综述了活性炭、金属氧化物、复合金属氧化物和活性炭负载金属氧化物干法脱除H₂S的研究进展.分析了活性炭和单一金属氧化物在使用温度、脱硫效率和再生等方面的优缺点,指出复合金属氧化物和活性炭负载金属氧化物在使用温度、硫化效率和再生性能等方面都有很大改进,是应用前景广阔的脱硫剂.根据它们脱硫的原理和特点,结合半焦和活性炭性质上的相似性,对半焦负载金属氧化物制备脱硫剂的可行性进行了探讨.     

Effects of reduction of metal oxide sorbents on reactivity and physical properties during hot gas desulphurization in IGCC

In this study, the changes of physical properties and reactivity of the metal oxide sorbents were investigated under the reducing conditions of coal gas. Metal oxide sorbents are converted into metal sulphides as a result of reaction with H₂S in synthesis gas. This could cause the reduced reactivity of sorbents if the metal oxides were converted into metallic elements due to the reduction by either hydrogen or carbon monoxide. In this experiment, the changes of physical properties and reactivity of the metal oxides were investigated over the temperature range 480-700 °C. It is confirmed that the reactivity of sulphidation and the reduction of metal oxide increased with increasing temperature. Even though the sulphur capacity of the sorbents in the early stage was high, it reduced rapidly due to the progressive reduction of metal oxides as the sulphidation/regeneration process was repeated. The reduction of metal oxide and the extent of reduction were verified by measuring the amount of oxygen consumed and the amount of SO₂ produced during the regeneration of sulphidated sorbents with the aids of a gas analyser. It was concluded that the reactivity of the metal oxide sorbents was influenced by reduction with coal gas at high temperature.     

Reactivity of Metal Oxide Sorbents for Removal of Sulfur Compounds from Coal Gases at High Temperature and Pressure

Abstract

Hot-gas desulfurization for the integrated gasification combined cycle (IGCC) process has been investigated to effectively remove hydrogen sulfide with various metal oxide sorbents at high temperatures and pressures. Metal oxide sorbents such as zinc titanate oxide, zinc ferrite oxide, copper oxide, manganese oxide, and calcium oxide were found to be promising sorbents in comparison with other removal methods such as membrane separation and reactive membrane separation. The removal reaction of H₂S from coal gas mixtures with zinc titanate oxide sorbents was conducted in a batch reactor. The main objectives of this research are to formulate promising metal oxide sorbents for removal of hydrogen sulfide from coal gas mixtures, to compare reactivity of a formulated sorbent with a sorbent supplied by the Research Triangle Institute at high temperatures and pressures, and to determine effects of concentrations of moisture contained in coal gas mixtures, and to determine effects of concentrations of moisture contained in coal gas mixtures on equilibrium absorption of H₂S into metal oxide sorbents. Promising durable metal oxide sorbents with high-sulfur-absorbing capacity were formulated by mixing active metal oxide powders with inert metal oxide powders and calcining these powder mixtures.     

燃料油吸附脱硫的研究进展

与传统的加氢脱硫技术相比,吸附脱硫技术在超低硫燃料油生产方面具有明显优势,近年来得到了迅速发展。综述了吸附法脱除燃料油中有机硫化物的研究进展,重点介绍了反应吸附脱硫和选择性吸附脱硫两种类型的吸附脱硫方法以及分子筛基吸附剂、金属氧化物基吸附剂、活性炭基吸附剂和粘土基吸附剂在吸附脱硫方面的应用。指出选择性吸附脱硫技术是近期最有希望实现零硫目标的脱硫技术。     

负载型煤气脱硫剂用载体的研究现状

煤气净化用脱硫剂的载体在脱硫剂硫化再生过程中具有重要的作用,好的载体不仅可以均匀分散活性组分、增大表面积,而且能够提高其耐热性和机械强度。在分析γ-Al2O3,活性炭和TiO2 3种常用载体在脱硫剂应用中存在的优势和不足的基础上,进行了载体改性的探讨,指出经过改性的载体以及复合型载体在脱硫领域将具有更为广泛的应用前景。     

微波固相法制备铁酸锌脱硫剂的硫化动力学

通过微波与常规固相法制备了铁酸锌高温煤气脱硫剂,使用X射线衍射（XRD）、氮吸附、扫描电子显微镜（SEM）以及X射线光电子能谱（XPS）对两种不同焙烧方式制备的脱硫剂的物相组成、织构形貌和表面元素进行了表征。数据显示微波焙烧制备的脱硫剂具有孔隙结构丰富、表面金属元素含量高、结合能低等优点。使用热天平对铁酸锌脱硫剂硫化行为进行了研究,根据等效粒子模型计算了两种脱硫剂与硫化氢气体反应的动力学参数,得到了硫化反应动力学方程,并在固定床上对其煤气脱硫性能进行了考察。结果表明硫化过程分为化学反应控制区和颗粒内扩散控制区。微波焙烧制备脱硫剂的化学反应活化能和颗粒内扩散活化能较低,说明其在硫化氢气体脱除上具有更高的活性。在模拟煤气气氛下,相比常规焙烧方法制备的脱硫剂,微波制备的脱硫剂的脱硫性能显著提高,具有更高的硫容和更长的精脱硫时间。     

Review of Experimental Characterization of Active Sites and Determination of Molecular Mechanisms of Adsorption,Desorption and Regeneration of the Deep and Ultradeep Desulfurization Sorbents for Liquid Fuels

This review analyzes the recent literature on the direct experimental determination of molecular and atomic-level nature of adsorption sites, mechanisms of adsorption under the mild (close to ambient) conditions, desorption of sulfur-aromatic compounds, and surface chemical reactions upon regeneration of the “spent” sorbents for desulfurization of the liquid fuels. Supported noble, transition metals and metal oxides, binary, and ternary metal oxides, activated carbons, zeolites, supported polymers, pervaporation membranes and other advanced adsorptive desulfurization materials are discussed. The recent trends in developing the deep and ultradeep desulfurization sorbents are discussed, and challenges of the direct determination of molecular mechanisms are described.     

Desulfurization matching with coal poly-generation system based on dual gas resources

The coal poly-generation system for the production of alcohol and ether fuels as well as power is one of advanced coal utilization techniques. The team leaded by Professor Xie Kechang is carrying out the research on the poly-generation system to produce the syngas from the combination of gasified and pyrolyzed coal gas (dual gas resources) for the alcohol ether synthesis. Gas desulfurization is one of the key technologies for this system. The desulfurization matching with dual gas resources based poly-generation system for the production of alcohol and ether fuels as well as power is presented according to gas components, sulfur content, sulfur species and desulfurization accuracy in this technology. This matching desulfurization is classified into hot gas desulfurization, normal gas desulfurization, warm gas desulfurization and organic sulfur catalytic conversion. The preparation of H₂S removal sorbents, organic sulfur hydrolysis catalyst and the evaluation of their activities involved in the system were investigated. The H₂S removal efficiencies of the crude and fine desulfurization sorbents prepared for hot gas desulfurization are 90% and 99% at 500 °C in simulating coal gas, and their sulfur capacities are 21.85 wt.% and 24.91 wt.%, respectively. The organic sulfur catalyst shows the high hydrolysis activity, and the hydrolysis conversion of COS is more than that of CS₂ on the same catalyst. The research will provide necessary information for the matching desulfurization technology in the demonstration project on dual gas resources coal poly-generation system.