超临界流体在生物质转化技术中的应用

生物质能作为具有潜力的清洁可再生能源已经成为共识,且日益受到人们的重视。超临界流体因其自身的特性能够提高生物质转化利用效率,本文分析介绍了超临界流体技术在生物质利用中的主要应用即生物质超临界预处理、制氢、液化以及生物柴油超临界制备和生物油超临界提质,提出生物质超临界利用技术的研究意见和发展建议。     

木材溶剂液化技术及其在制备高分子材料中的应用

木质材料经过热化学液化,可进一步制备酚醛树脂、聚氨酯等高分子材料.本文介绍了木材液化技术制备高分子材料的发展状况,包括液化方法、木材主成分的液化机理以及液化生成物的应用,指出在木材液化反应机理、液化产物的利用和最佳液化工艺的开发等方面尚有待进一步研究,并提出充分利用木材的生物降解性,开发木材液化物与其他材料复合的新型高分子材料具有广泛的前景.     

木材溶剂液化技术及其在制备高分子材料中的应用

木质材料经过热化学液化,可进一步制备酚醛树脂、聚氨酯等高分子材料。本文介绍了木材液化技术制备高分子材料的发展状况,包括液化方法、木材主成分的液化机理以及液化生成物的应用,指出在木材液化反应机理、液化产物的利用和最佳液化工艺的开发等方面尚有待进一步研究,并提出充分利用木材的生物降解性,开发木材液化物与其他材料复合的新型高分子材料具有广泛的前景。     

生物质转化利用技术的研究进展

生物质能源和石油替代产品的研究、开发和应用,是保障能源供应、减少对化石能源的依赖、解决未来能源问题的有效途径。综述了目前国内外生物质能的转化利用技术,主要包括直接燃烧技术、生化转化技术(发酵和厌氧性消化)、热化学转化技术(气化、热解)、液化技术、致密成型技术、超临界流体转化技术等;介绍了生物质转化技术的应用,包括生物质气化发电、气化制氢、热裂解制氢、发酵法生产燃料乙醇、热裂解制生物油、固化成型制固态燃料、堆肥发酵制肥料、厌氧性消化生产沼气、催化裂解生产生物燃料等。对未来的生物质能利用技术的发展进行了展望。     

生物质热转换制氢的研究进展

氢气是一种理想的洁净能源。从能源角度和环境角度考虑,发展生物质制氢技术都具有重要的意义。生物质制氢技术主要包括热化学法和生物法,其中热化学法主要是将生物质气化或液化,再进行重整和水蒸气变换反应,获得氢气。本文综述了生物质热化学转化(包括气化、超临界水气化、热裂解等)制氢技术的研究进展,并对典型的制氢技术作了评述和展望。     

生物质的热解气化

生物质是可再生资源。在所有生物质资源中,植物资源的量最大,特别是林产植物资源最丰富。据统计,1980年世界森林面积为3亿公顷。木材蓄积量为3270亿立方米。用生物质代替能源,主要采用气化和液化两种工艺路线。目前,实际使用的代表性例子是巴西的酒精发酵和中国的甲烷(沼气)发酵。这两个国家应用得都很普遍,并且取得了一定的成果。但木质生物质除直接用作燃料外,实际代替能源的还不多。木材的液化燃料化研究,主要目标是酒精发酵,但预处理     

超临界水中生物质气化制氢

超临界水中生物质气化制氢技术是近年发展起来的一种高效、清洁的能源转化及利用技术，无论从能源还是环境角度，都具有十分重要的意义。文章主要介绍了超临界水中生物质气化制氢的发展、原理、设备及影响因素等，并对其前景作了一定的预测。     

综合利用废弃木质物

废弃木质物指木材加工余料、树皮、各种农作物秸杆、稻壳、果壳等。它们是丰富的生物质能源。开发利用废弃木质物,关键是要抓转化技术,即使废弃木质物转化为更有效的能源。我国是一个农业大国,年年有大量的废弃木     

木材液化技术的研究进展

综述了近30年来国内外木材液化技术的研究进展,简介了以酸或碱为催化剂、无催化剂和超临界萃取等木材液化的主要方法,木材液化技术对充分利用自然界中可再生资源、降低环境污染具有重要的意义.     

生物质气化技术及进展

能源和环境的双重压力使得可再生清洁能源的开发利用越来越重要。生物质能是地球上重要的可再生能源,具有广阔的发展前景。我国有着丰富的生物质资源,开发和利用生物质能源对于缓解我国能源、环境及生态问题都具有重要的意义。文章介绍了生物质气化技术的原理及研究进展,分析了气化过程中存在的主要问题,并指出了气化技术的研究方向。     

A new pulverized biomass utilization technology

Pulverized wood biomass utilization technologies, such as gasification and liquefaction, were discussed. Firstly, pulverization technique of wood biomass by a vibration mill was introduced, and pulverized wood biomass characteristics were evaluated. The wood powder pulverized by the vibration mill had a round shape, and the wood fibers were completely broken. Therefore, the diameter of wood powder was fine and the crystallinity of cellulose was very low. By using this pulverized wood biomass, high temperature gasification experiment and liquefaction experiment were conducted. Gasification experiment was conducted in an entrained down flow gasifire. Since fine wood powder had a high reactivity, the gasification experiment showed the high gasification performance without a tar generation. Liquefaction experiment of wood biomass was conducted in a hot compressed water to produce saccharine. Pulverized wood biomass was also used as a raw material in the liquefaction experiment. By using very fine wood powder, productivity of saccharine increased dramatically.     

木质生物质的液化及其产物的高效利用研究进展

对国内外木质生物质原料的液化及液化产物的高效利用研究的现状及进展进行了概述,讨论了木质生物质原料液化及其产物的应用前景,重点讨论了不同木质生物质原料液化过程中的主要影响因素,并分析了具有代表性的液化物结构特点,具体介绍了一些液化产物实际应用特别是在胶黏剂制备方面应用的典型实例。对我国该领域研究存在的问题、产业化发展提出了一些看法。     

生物质能高效利用研究进展

综述了近年来国内外生物质高效利用的技术进展,分别对生物质气化制富氢燃气和生物质液化制生物油的最新研究进行介绍。分析了对生物质气化、液化反应过程和收率及产品组成的主要影响因素。展望了生物质能未来的发展趋势,并指出生物质高效利用技术具有广阔的发展前景。     

Pretreatment of wood flour slurries prior to liquefaction

As part of the UDES-S solvolytic approach to wood fractionation and liquefaction, a pretreatment stage has been developed using a fed batch technique to produce high solids content slurries. By using a combination of temperature and shear stress across homogenizing valves, wood flour slurries of Populus spp having concentrations of 20-32% by weight in both paraffin oil and ethylene glycol have been produced. Optical and scanning electron microscopy have shown that the recirculation loop and homogenizing valve cause structural degradation, defibration and defibrillation of the original particles as well as partial solubilization of the wood components. The maximum wood flour concentration, attainable before plugging was observed in the small scale system used, was just below 36% by weight. High concentration slurries are a prerequisite in order to obtain realistic reactor space velocities in biomass liquefaction processes.     

Flaming pyrolysis model of the fixed bed cross draft long-stick wood gasifier

The future industrial development of biomass energy depends on the application of renewable energy technology in an efficient manner. Of all the competing technologies under biomass, gasifiers are considered to be one of most viable applications. The use of biomass fuel, especially biomass wastes, for distributed power production can be economically viable in many parts of the world through gasification of biomass. Since biomass, is a clean and renewable fuel, gasification gives the opportunity to convert biomass into clean fuel gas or synthesis gas for industrial uses. The preparation of feedstock for a gasifier requires time, energy and labour and this has been a setback for gasifier technology development. The present work is focused on gasification of long-stick wood as a feed material for gasifiers. This application makes reduction not only in the cost but also on the power consumption of feed material preparation. A 50 m³/h capacity gasifier was fabricated in the cross draft mode. The cross draft mode makes it possible to produce low tar content in producer gas. This cross draft mode operates with 180 W of blower supply for air to produce 10 kW of thermal output. The initial bed heights of the long-stick wood and charcoal are 58 cm and 48 cm respectively. Results were obtained for various flow conditions with air flow rates ranging from 20 to 30 m³/h. For modelling, the flaming pyrolysis time for long-stick wood in the gasifier is calculated to be 1.6 min. The length of the flaming pyrolysis zone and char gasification zone is found to be 34 cm and 30 cm respectively. The rate of feed was between 9 and 10 kg/h. Continuous operation for 5 h was used for three runs to study the performance. In this study we measured the temperature and pressure in the different zones as a function of airflow. We measured the gas flow and efficiency of the gasifier in order to determine its commercial potential for process and power industries.     

微波液化木材及聚醚多元醇的制备

以醇解的聚酯(PET)饮料瓶为液化剂,甘油作辅助液化剂,微波辅助加热,用2.5%H2SO4催化液化木材。分别讨论了微波功率、液固比/反应时间和温度对液化率的影响。结果表明,在微波功率500 W,反应时间15 m in,温度150℃,液固比为4的条件下,木材液化率99.16%。以此液化物为起始剂,选用双金属氰化物MMC催化环氧丙烷开环聚合,通过改变环氧丙烷的用量制备了不同聚醚多元醇,并采用傅里叶变换红外(FT-IR)、凝胶色谱(GPC)及热示差扫描(DSC)等分析手段对起始剂和不同聚醚多元醇的结构、分子质量分布和耐热性进行了对比表征。研究表明聚醚多元醇的羟值、酸值、黏度随环氧丙烷用量增加减小,分子质量分布随之变窄,热稳定性下降。     

木质液化物静电纺丝法制备纳米纤维可行性研究

从静电纺丝法纳米纤维制备的特点及其应用领域,对静电纺丝法纳米纤维制备的研究现状进行了全面的归纳,并在此基础上,对今后以木质液化物为对象,通过静电纺丝法进行生物质纳米纤维制备存在的技术问题和今后的研究工作提出了建议。     

Liquefaction of Red Pine Wood,Pinus densiflora,Biomass Using Peg-400-Blended Crude Glycerol for Biopolyol and Biopolyurethane Production

Red pine wood, Pinus densiflora, biomass was liquefied through liquefaction using a solvent mixture of crude glycerol and PEG-400 with a sulfuric acid catalyst. The liquefaction process parameters of crude glycerol/PEG-400 blending ratio, biomass loading, acid loading, reaction temperature, and reaction time were optimized. Biopolyol with 61.9% biomass conversion was produced at 170°C within 1 h using a co-solvent of crude glycerol and PEG-400 (5/5, w/w), 15% biomass loading, and 3% sulfuric acid loading. The biopolyol possessed a 4.2 mg KOH/g acid number and 892.4 mg KOH/g hydroxyl number. Polyurethane foam was successfully synthesized from the liquefied red pine wood biomass with toluene diisocyanate. The synthesis of biopolyurethane derived from red pine wood biopolyol was confirmed with FT-IR.