中型生物质气化发电系统设计及运行分析

中等规模的生物抟气化发电（１－５ＭＷ）,现阶段在我国具有特别重要的意义。从系统匹配的角度,阐述了中型生物质气化发电系统中气化炉、净化系统及内燃机三部分的相互关系和设计要点,指出４００ｋＷ以上发电系统最好选用循环流化床气化炉。     

生物质气化技术讲座(六)国外生物质气化技术的应用

近些年来 ,生物质气化及其应用技术在国外发展较快 ,生物质可燃气多用于发电 ,也用于合成化学品、烘干物料以及为生活供热等。１生物质气化发电国外采用的生物质气化发电机组基本上有３种类型 :一是内燃机—发电机机组 ;二是汽轮机—发电机机组 ;三是燃气轮机—发电机机组。有的发电厂将前两种类型联合使用 ,即先利用内燃机发电 ,再利用系统的余热生产蒸汽 ,推动汽轮机做功发电 ;也有的发电厂将后两种类型联合使用 ,即用燃气轮机发电系统的余热生产蒸汽 ,推动汽轮机做功发电 ,这种发电形式发展前景较广阔。图１至图３分别是上述３种发电机组…     

生物质气化技术讲座(五)生物质气化发电与生物质热裂解工程

生物质气化发电主要有３种方式：一是将可燃气作为内燃机的燃料,用内燃机带动发电机发电;二是将可燃气作为燃气轮机的燃料,用燃气轮机带动发电机发电;三是用燃气轮机和汽轮机实现两级发电,即利用燃气轮机排出的高温废气把水加热成蒸汽,再用蒸汽推动汽轮机带动发电机发电。我国主要是采用第一种方式进行生物质气化发电,并开始研究和探讨后两种发电方式。本讲还要简要介绍生物质热裂解工程实例。１我国生物质气化发电发展概况我国生物质气化发电所用原料以谷壳（尤其是稻壳）为主。早在６０年代,我国就开始了生物质气化发电的研究,研…     

生物质气化发电示范工程

由中科院广州能源研究所承担的国家“十五”863项目“生物质气化发电优化系统及其示范工程”，已开发出适合我国国情的生物质中小型气化发电系统。该技术采用CFB气化炉和多级气体净化装置，配置多台200-400kW的气体燃料内燃发电机组用谷壳、木屑、稻草等多种生物质作原料来发电。     

生物质气化发电示范工程

由中科院广州能源研究所承担的国家“十五”期间863项目的生物质气化发电优化系统及其示范工程．已开发出适合我国国情的生物质中小型气化发电系统。该技术采用CFB气化炉和多级气体净化装置，配置多台200～400kW的气体燃料内燃发电机组，用谷壳木屑、稻草等多种生物质作原料来发电。     

生物质气化技术的应用

随着生物质气化技术的日趋成熟，生物质气化系统的应用范围越来越广范。目前，生物质气化系统的开发应用主要有气化烘干、气化发电、家用燃气集中供气和户用气化炉灶四个方面。1生物质气化烘干系统包括气化炉、滤清器、燃烧器、混合换热器及用能终端装置。气化炉木材干燥系统如图1所示。气化炉供热量为4．2×104～6．3×104kJ/h，燃气热值为5040～5880kJ／m3，气化效率达70％以上。与常规烘干设备相比火化炉具有升温快、火力强、干燥质量好的优点，并能缩短烘干周期60％，降低成本50％。目前已用于木材、茶叶、烟草、谷物等的烘干。2生物质…     

我国生物发电研究新成果

中科院广州能源研究所承担的“十五”863项目“生物质气化发电优化系统及其示范工程”，目前已取得阶段性成果．开发出适合我国国情的生物质中小型气化发电系统。采用循环流化床气化炉和多级气化净化装置。配置多台200-400kW的单气体燃料内燃发电机组，用谷壳、木屑、稻草等多种生物质作原料，可以在不同的负荷下运行。     

生物质气化发电技术讲座(2)生物质气化工艺的设计与选用

生物质的气化有各种各样的工艺过程。从理论上讲,任何一种气化工艺都可以构成生物质气化发电系统。但从气化发电的质量和经济性出发,生物质气化发电要求达到发电频率稳定、发电负荷连续可调两个基本要求,所以对气化设备而言,它必须保证燃气质量稳定、燃气产量可调,而且必须连续运行。在这些前提下,气化能量转换效率的高低就是影响气化发电系统运行成本的关键。气化形式选定以后,从系统匹配的角度考虑,气化设备应满足以下要求:从实际应用上考虑,固定床气化炉比较适合于小型、间歇性运行的气化发电系统,它的最大优点是原料不用预处理,而且设备…     

MW级生物质气化发电站运行特性分析

结合浙江省长兴市某大米加工厂800kW稻壳气化发电系统测试结果,对MW级生物质气化发电站的运行特性进行了详细分析,重点考察了气化温度、当量比和负荷对生物质流化床气化特性的影响,并对系统存在的问题进行了讨论。气化炉轴向温度分布表明:床内存在流化不充分现象;密相区温度与当量比和负荷(加料速率)变化密切相关(负荷不变,床温随当量比增加近似线性升高;当量比相同,较高负荷对应较低的床温)。燃气热值随气化温度升高而降低,负荷变化对其影响不大。当气化温度保持在700~800℃之间时,燃气热值基本稳定在5453~6407kJ/Nm3。原料水分对气化炉的运行也有重要影响:当原料水份低于15%,水分含量增加,有助于提高运行气化当量比,提高燃气品质和产气率;然而原料水分含量超过15%,气化炉温度将很难控制。     

生物质气化耦合发电炉型选择及应用分析

结合国家能源局对生物质耦合发电技改试点的批复,分析耦合发电技改工艺发展趋势,对比直接耦合、气化耦合及蒸汽耦合方式的发电效率及投资成本,就气化耦合方式开展调研。对不同生物质气化炉在处理规模、燃气特性及组成方面与气化耦合发电需求进行了匹配,参考国内外耦合发电的实施案例,选择气化耦合最适炉型,并分析现存政策及市场气化耦合存在的问题。     

冷热电三联供系统的优化研究

冷热电联供系统主要应用于大型集中性供能系统中。作为分布式能源的一种,冷热电联供系统具有节约能源、改善环境、提高电力综合效益的优势。一般情况下,三联供系统是以天然气为燃料带动燃气轮机、微燃机或内燃机发电机等燃气发电设备运行,产生的电力供应用户的电力需求,系统发电后排出的余热通过余热回收利用设备(余热锅炉或者余热直燃机等)向用户供热、供冷。通过这种方式提高整个系统的一次能源利用率,实现能源的梯级利用,还可以提供并网电力作能源互补,经济收益和效率均得以提升。研究较为常见的燃气轮机中的一种蒸汽型吸收式冷热电联产系统,对不同配置方式和运行方式进行横向与纵向交叉比较,以完成系统优化研究。     

An update technology for integrated biomass gasification combined cycle power plant

A discussion is presented on the technical analysis of a 6.4 MW_e integrated biomass gasification combined cycle (IBGCC) plant. It features three numbers of downdraft biomass gasifier systems with suitable gas clean-up trains, three numbers of internal combustion (IC) producer gas engines for producing 5.85 MW electrical power in open cycle and 550 kW power in a bottoming cycle using waste heat. Comparing with IC gas engine single cycle systems, this technology route increases overall system efficiency of the power plant, which in turn improves plant economics. Estimated generation cost of electricity indicates that mega-watt scale IBGCC power plants can contribute to good economies of scale in India. This paper also highlight’s the possibility of activated carbon generation from the char, a byproduct of gasification process, and use of engine’s jacket water heat to generate chilled water through VAM for gas conditioning.     

生活垃圾气化甲烷化发电技术

我国生活垃圾产量逐年增加,焚烧是目前主流的生活垃圾减量化和资源化处理技术。但是未经预处理的生活垃圾成分复杂、热值偏低,导致在焚烧过程中存在污染物排放和发电效率低等问题。针对上述问题提出了一种全新的生活垃圾气化甲烷化发电技术。该技术将生活垃圾筛选、破碎、干化后制成废弃物衍生燃料RDF-5,利用气化、净化、甲烷化工艺制成高热值可燃气体,并采用内燃机-蒸汽轮机联合循环发电,能够降低污染物排放并提高发电效率。基于该技术,对各个工艺环节开展分析讨论与比较选型,以每天处理300t RDF-5燃料为例,进行了热平衡计算及发电机组配置方案设计。     

生物质流化床燃烧/气化的烧结特性与机理综述

流化床燃烧/气化是生物质高效规模化能源利用的主要方式之一,由于生物质在较低温度下燃烧/气化时就容易发生床料烧结,影响了系统安全稳定运行,阻碍了能源利用效率的提高.系统地归纳了不同生物质在不同种类床料状态下燃烧/气化时烧结所需的特征温度,分析了生物质种类、碱金属含量、反应气氛与烧结温度之间的联系,结合相关研究,对生物质的烧结机理进行了分析和总结,对烧结温度预测方法和模型的优缺点进行了剖析和比较,对生物质燃烧/气化烧结机理进一步研究、预测模型的优化等提出了积极的建议,以期为相关研究的深入开展和生物质能规模化利用水平的提高提供有意义的参考.     

Distributed power generation via gasification of biomass and municipal solid waste: A review

The access to electricity has increased worldwide, growing from 60 million additional consumers per year in 2000–2012 to 100 million per year in 2012–2016. Despite this growth, approximately 675 million people will still lack access to electricity in 2030, indicating that electricity demand will continue to increase. Unfortunately, traditional large fossil power technologies based on coal, oil and natural gas lead to a major concern in tackling worldwide carbon dioxide emissions, and nuclear power remains unpopular due to public safety concerns. Distributed power generation utilizing CO₂-neutral sources, such as gasification of biomass and municipal solid wastes (MSW), can play an important role in meeting the world energy demand in a sustainable way. This review focuses on the recent technology developments on seven power generation technologies (i.e. internal combustion engine, gas turbine, micro gas turbine, steam turbine, Stirling engine, organic rankine cycle generator, and fuel cell) suitable for distributed power applications with capability of independent operation using syngas derived from gasification of biomass and MSW. Technology selection guidelines is discussed based on criteria, including hardware modification required, size inflexibility, sensitivity to syngas contaminants, operational uncertainty, efficiency, lifetime, fast ramp up/down capability, controls and capital cost. Major challenges facing further development and commercialization of these power generation technologies are discussed.     

Main routes for the thermo-conversion of biomass into fuels and chemicals. Part 2: Gasification systems

Gasification as a thermo-chemical process is defined and limited to combustion and pyrolysis. The gasification of biomass is a thermal treatment, which results in a high production of gaseous products and small quantities of char and ash. The solid phase usually presents a carbon content higher than 76%, which makes it possible to use it directly for industrial purposes. The gaseous products can be burned to generate heat or electricity, or they can potentially be used in the synthesis of liquid transportation fuels, H₂, or chemicals. On the other hand, the liquid phase can be used as fuel in boilers, gas turbines or diesel engines, both for heat or electric power generation. However, the main purpose of biomass gasification is the production of low- or medium heating value gas which can be used as fuel gas in an internal combustion engine for power production. In addition to limiting applications and often compounding environmental problems, these technologies are an inefficient source of usable energy.     

Black liquor gasification—consequences for both industry and society

The pulp and paper industry consumes large quantities of biofuels to satisfy process requirements. Biomass is however a limited resource, to be used as effectively as possible. Modern pulping operations have excess internal fuels compared to the amounts needed to satisfy process steam demands. The excess fuel is often used for cogeneration of electric power. If market biofuel availability at a reasonable price is limited, import/export to/from a mill however changes the amount of such biofuel available for alternative users. This work compares different mill powerhouse technologies and CHP plant configurations (including conventional recovery boiler technology and black liquor gasification technology) with respect to electric power output from a given fuel resource. Different process steam demand levels for different representative mill types are considered. The comparison accounts for decreased/increased electricity production in an alternative energy system when biofuel is imported/exported to/from the mill. The results show that black liquor gasification is in all cases considered an attractive powerhouse recovery cycle technology. For moderate values of the marginal electric power generation efficiency for biofuel exported to the reference alternative energy system, excess mill internal biofuel should be used on mill site for gas turbine based CHP power generation. The remaining excess biofuels in market pulp mills should be exported and used in the reference alternative energy system in this case. For integrated pulp and paper mills, biofuel should be imported, but only for cogeneration usage (i.e. condensing power units should be avoided). If biofuel can be used elsewhere for high efficiency CHP power generation, mill internal biofuel should be used exclusively for process heating, and the remainder should be exported.     

Biomass gasification integrated with pyrolysis in a circulating fluidised bed

The use of biomass for energy generation is getting increasing attention. At present, gasification of biomass is taken as a popular technical route to produce fuel gas for application in boilers, engine, gas turbine or fuel cell. Up to now, most of researchers have focused their attentions only on fixed-bed gasification and fluidised bed gasification under air-blown conditions. In that case, the producer gas is contaminated by high tar contents and particles which could lead to the corrosion and wear of blades of turbine. Furthermore, both the technologies, particularly fixed bed gasification, are not flexible for using multiple biomass-fuel types and also not feasible economically and environmentally for large scale application up to 10–50 MW_th. An innovative circulating fluidised bed concept has been considered in our laboratory for biomass gasification thereby overcoming these challenges. The concept combines and integrates partial oxidation, fast pyrolysis (with an instantaneous drying), gasification, and tar cracking, as well as a shift reaction, with the purpose of producing a high quality of gas, in terms of low tar level and particulates carried out in the producer gas, and overall emissions reduction associated with the combustion of producer gas. This paper describes our innovative concept and presents some experimental results. The results indicate that the gas yield can be above 1.83 N m³/kg and the fluctuation of the gas yield during the period of operation is 3.3% at temperature of 750 °C. Generally speaking, the results achieved support our concept as a promising alternative to gasify biomass for the generation of electricity.     

我国的燃气_蒸汽联合循环发电技术前景良好

针对我国能源结构和能源政策，指出燃气－蒸汽联合循环是提高发电效率和解决环境污染的重要途径，尤其是国际公认的最有发展前途的两种燃煤联合循环发电技术；ＩＧＣＣ和ＰＦＢＣ－ＣＣ。文中简要地介绍了这两种联合循环发电技术。     

Optimal power generation from low concentration coal bed methane in Iran

Development of a model for optimal power generation from the thermal oxidation of a low concentration coal bed mine has been considered as the main objective of this investigation. The model has been applied to identify the optimal thermodynamic characteristics of the power generation system through using a mixture with 1.6% methane concentration in a recuperative lean-burn gas turbine and coupling a gas engine to the system for more power generation from the remaining coal bed methane. The implementation of the model based on the real site condition would lead to the generation of 6.97 MW electricity in Tabas coal mine of Iran.