生物质成型燃料产业研究现状及发展分析

在论述生物质成型燃料特性及适用性的基础上,介绍生物质成型燃料国内产业发展现状及技术水平,分析了成型燃料在中国的技术、市场、项目建设及模式问题,并对生物质成型燃料产业发展提出了建议.     

生物质成型燃料燃烧理论分析

根据试验结果，分析了总结了生物质成型燃料的点火性能、燃烧机理、燃烧特性等燃烧规律，从而为确定生物质成型燃料燃烧设备的热力特性参数打下基础，为研制生物质成型燃料专用燃烧设备提供科学依据。     

生物质固体成型燃料环模成型技术研究进展

综合分析了国内外生物质固体成型燃料环模成型技术、成型设备及产业发展现状.比较了生物质环模颗粒成型机和生物质环模压块成型机的性能和产品,指出了生物质固体成型燃料环模技术及设备存在着基础理论薄弱、原料适应差、易损件寿命短等问题;提出了我国生物质固体成型燃料环模成型技术的发展方向.     

生物质成型燃料化学实验分析

生物质对提高能源利用率和缓解环境污染具有非常重要的作用。以松木、棉柴、花生壳和玉米秸秆这4种典型生物质成型燃料为实验材料,分析其化学特性。结果表明:当原料配比为80%松木+20%花生壳或玉米秸秆时,生物质成型燃料燃烧效率最高,其研究结果可为生物质燃料的高效清洁燃烧提供理论依据。     

波兰生物质成型燃料的发展及借鉴

波兰具有丰富的生物质资源,拥有完整的生物质成型燃料产业链,近年来随着欧盟生物质能源促进政策的推出与市场需求量,生物质成型燃料产业发展潜力巨大。2010年,生物质成型燃料产量超过1 200万t,相当于近58万t油当量,预计到2030年,生物质能源将达到747×1015J,相当于约1 778万t标煤,其中生物质成型燃料产量占80%以上。文章通过研究波兰生物质成型燃料的发展过程、产业政策、质量标准与评价以及应用等,分析了我国与波兰生物质成型燃料发展的异同,借鉴波兰发展经验,提出了适合我国生物质成型燃料的发展建议,以促进我国生物质成型燃料产业化进程。     

固体生物质燃料燃烧颗粒物排放研究状况

介绍了固体生物质燃料和空气中颗粒污染物的特点,从形成机理、质量浓度、数量浓度、分布特点以及颗粒物成分方面阐述了国内外对颗粒物排放的研究;分析了国内外对固体生物质燃料的颗粒物排放存在的问题,根据我国固体生物质燃料的特点,提出了我国生物质固体成型燃料颗粒物排放的研究方向。     

生物质燃料转化利用技术的现状、发展与锅炉行业的选择

介绍了生物质成型、生物质气化、生物质液化及热解多联产等几种常见的生物质转化技术。分析了生物质燃料在锅炉行业中的利用现状及存在的主要问题,并指出锅炉行业未来应立足生物质燃料的发展,并朝着原料绿色化、生产清洁化和产品智能化的方向发展。     

生物质成型燃料链条炉主要设计参数的试验确定

根据生物质成型燃料燃烧特性、链条炉热力学特性及燃烧设备的设计实践经验,在特制的生物质成型燃料链条炉上,结合工业锅炉热工性能试验规程(GB 10180-2003)、工业锅炉节能监测方法(GB/T15317-1994)、锅炉烟尘测试方法(GB 5468-91)和锅炉大气污染物排放标准(GB 13271-2014),对4种工况进行试验,确定出生物质成型燃料链条炉主要设计参数,从而为生物质成型燃料链条炉的设计及技术改造提供科学依据。     

加快制定我国生物质成型燃料的标准

生物质成型燃料是生物质能开发利用的一个重要途径。加快生物质成型燃料标准规范的制订是促进生物质成型燃料产业化发展的重要环节。借鉴欧洲国家的生物质成型燃料标准经验，从注重我国用户的使用需求、生产和运输的方便性以及燃料的清洁性出发，加快制定适合我国的生物质成型燃料标准。     

生物质成型燃料研究现状及进展

本文讨论了发展生物质成型燃料的意义,详细介绍了国内外生物质成型燃料的发展历程及现状,介绍了一些目前采用的新技术和存在的问题.最后对生物质成型燃料的未来进行了展望,指出生物质成型燃料在节能及环保方面将大有作为.     

木屑致密成型燃料微观结构观察与分析

林木生物质在全球生物质储量中占有很大比例,本文以木屑致密成型燃料为研究对象。试验分别对木屑致密成型燃料进行了元素分析、工业分析和燃料组成分析。并在200 kV场发射透射电子显微镜(JEM-2100F)下对木屑致密成型燃料进行观察,分别得到放大倍数为100、500、1 000、2 000倍的微观结构图片。通过对木屑成型燃料的微观结构分析研究能够为生物质成型燃料加工成型设备和燃烧设备的优化设计与改进提供理论基础。     

Optimum conditions for a natural gas combined cycle power generation system based on available oxygen when using biomass as supplementary fuel

Due to the higher oxygen content and lower heating value, the amount of biomass required in a combined cycle, where it is used as supplementary fuel, to meet a given energy demand is such that the biomass consumes almost all of the oxygen remaining from gas turbine combustion process under certain conditions. This situation requires additional air for biomass combustion thus reducing the cycle efficiency and the net work output rate while increasing CO₂ emissions. Three conditions at which the oxygen is completely consumed are identified based on alterations in net fuel utilization. The first condition is linked to fuel utilization, which is observed to be significantly affected by variations in temperatures at three locations in the combined cycle (air temperature entering the gas turbine combustion chamber, gas turbine inlet temperature and HRSG inlet temperatures). The second condition relates to the characteristics of the feedstock (oxygen content of the biomass and heating value of natural gas). The heat loss due to combustion of natural gas and biomass is the third condition that affects oxygen availability. The current work assesses these conditions in order to identify the proper condition at which no additional air is required for supplementary firing of biomass.     

水热处理对生物质成型炭理化性质的影响

棉秆(CS)及木屑(WS)经高压反应釜水热预处理后压制成型,并于固定床热解炉内进行炭化实验,利用电子万能材料试验机、热重分析仪等分析手段分析水热预处理对生物质成型炭的产率、物理性能(机械强度和表观密度)、热值及燃烧性能的影响。研究表明:随着水热温度的升高,生物质成型炭的产率增加且热值稳定,但燃烧性能变差;经水热预处理制得的生物质成型炭灰分产率均小于18%,固定碳产率均大于60%,满足欧标要求;随着水热温度的升高,生物质成型炭的表观密度及抗压强度均先增加后减小;对比所有实验样品,经230℃水热预处理制得的生物质成型炭(CS/WS-HT230-CB)物理性能及燃烧性能最佳,且均优于商用烧烤炭性能。     

Experimental study on oxygen-enriched combustion of biomass micro fuel

The oxygen-enriched combustion of biomass micro fuel (BMF) was carried out respectively in the thermogravimetric analyzer and cyclone furnace to evaluate the effects of oxygen concentration on combustion performance. The experimental results show that with the increasing oxygen concentration, the volatile releasing temperature, ignition temperature and burnout temperature were decreasing. Oxygen-enriched atmosphere subtracts burning time and improves combustion activity of biomass micro fuel. Oxygen-enriched atmosphere improves the combustion temperature of BMF in cyclone furnace; while the improvement is weaken as oxygen concentration is above 40%.     

Combustion,cofiring and emissions characteristics of torrefied biomass in a drop tube reactor

The study investigates cofiring characteristics of torrefied biomass fuels at 50% thermal shares with coals and 100% combustion cases. Experiments were carried out in a 20 kW, electrically heated, drop-tube reactor. Fuels used include a range of torrefied biomass fuels, non-thermally treated white wood pellets, a high volatile bituminous coal and a lignite coal. The reactor was maintained at 1200 °C while the overall stoichiometric ratio was kept constant at 1.15 for all combustion cases. Measurements were performed to evaluate combustion reactivity, emissions and burn-out.Torrefied biomass fuels in comparison to non-thermally treated wood contain a lower amount of volatiles. For the tests performed at a similar particle size distribution, the reduced volatile content did not impact combustion reactivity significantly. Delay in combustion was only observed for test fuel with a lower amount of fine particles. The particle size distribution of the pulverised grinds therefore impacts combustion reactivity more.Sulphur and nitrogen contents of woody biomass fuels are low. Blending woody biomass with coal lowers the emissions of SO₂ mainly as a result of dilution. NO_X emissions have a more complex dependency on the nitrogen content. Factors such as volatile content of the fuels, fuel type, furnace and burner configurations also impact the final NO_X emissions. In comparison to unstaged combustion, the nitrogen conversion to NO_X declined from 34% to 9% for air-staged co-combustion of torrefied biomass and hard coal. For the air-staged mono-combustion cases, nitrogen conversion to NO_X declined from between 42% and 48% to about 10%–14%.     

生物质固体成型燃料燃烧监测技术与设备研究

介绍了典型的生物质固体成型燃料自动燃烧器和成型燃料炉排式锅炉,分析了国家相关设备的热工性能检测指标、污染物排放监测指标及国内外成型燃料燃烧设备的监测系统的差距,指出我国目前存在的燃烧设备检测监测标准缺乏、不完善,监测设备独立、单一及未成系统等问题,提出提高燃烧效率,建立统一的评价标准等相关建议,以期为我国生物质固体成型燃料产业发展提供参考。     

The characteristics of air pollutants from the combustion of biomass pellets

Biomass is renewable clean energy. The aim of this study is to explore the combustion properties and emission characteristics of NO_X, SO₂, PM, and HCl in the combustion process of biomass pellet fuels. In this study, three kinds of fuels (pine sawdust, mixed wood, and corn straw) were selected to be studied by using a tube furnace to simulate industrial boiler. Experiments were conducted under different combustion conditions (combustion temperature and air flow). The results show that pollutant emissions were related to fuel type, combustion temperature, and air flow. The emissions of NO_X were contingent on N content in the fuel and the peak emissions of NO_X appeared in the range of 50~600 mg/m³ at 4 L/min and 700℃. The emissions of SO₂ were related to combustion condition and close to zero under the condition of sufficient combustion. The emissions of HCl and particulate matter (PM) increase with the rise of temperature, but the emission of PM was minimal at 800℃. Average HCl emission was 0.2~0.5 mg/g under steady-state conditions (4 L/min and 700℃). All in all, the pollutant emissions of biomass pellet fuels during combustion are lower than those of the traditional fuel, and the combustion efficiency is relatively higher.     

生物质型煤的研制与应用

生物质型煤是一种新型型煤,是利用粉煤、生物质等通过一定的生产工艺制作而成,不仅有利于节约能源,同时也可以减少环境污染.文章重点介绍了水分、生物质添加量、粘结剂、原料煤粒度、成型压力、熟化过程、干燥程度对生物质型煤冷强度的影响,添加剂、生物质、配煤量以及煤的种类对生物质型煤热强度的影响.文章还分析了生物质型煤与生物质和煤在燃烧速度和着火性能上的区别,固硫效果与所加固硫剂量之间的关系,并提出了生物质型煤作为气化型煤今后应开展的研究方向与课题.     

Grate-firing of biomass for heat and power production

As a renewable and environmentally friendly energy source, biomass (i.e., any organic non-fossil fuel) and its utilization are gaining an increasingly important role worldwide. Grate-firing is one of the main competing technologies in biomass combustion for heat and power production, because it can fire a wide range of fuels of varying moisture content, and requires less fuel preparation and handling. The basic objective of this paper is to review the state-of-the-art knowledge on grate-fired boilers burning biomass: the key elements in the firing system and the development, the important combustion mechanism, the recent breakthrough in the technology, the most pressing issues, the current research and development activities, and the critical future problems to be resolved. The grate assembly (the most characteristic element in grate-fired boilers), the key combustion mechanism in the fuel bed on the grate, and the advanced secondary air supply (a real breakthrough in this technology) are highlighted for grate-firing systems. Amongst all the issues or problems associated with grate-fired boilers burning biomass, primary pollutant formation and control, deposition formation and corrosion, modelling and computational fluid dynamics (CFD) simulations are discussed in detail. The literature survey and discussions are primarily pertaining to grate-fired boilers burning biomass, though these issues are more or less general. Other technologies (e.g., fluidized bed combustion or suspension combustion) are also mentioned or discussed, to some extent, mainly for comparison and to better illustrate the special characteristics of grate-firing of biomass. Based on these, some critical problems, which may not be sufficiently resolved by the existing efforts and have to be addressed by future research and development, are outlined.