氢氧化钠改性生物质作型煤粘结剂的研究

探讨了以氢氧化钠改性的生物质作为型煤粘结剂的可能性。所选的生物质为价廉物广的稻草。笔发现粘结剂制备中主要的影响因素是氢氧化钠的浓度，该粘结剂固相组分的粘结能力强于液体部分。氢氧化钠处理的稻草分解物粘结剂中掺加膨润土、焦油或聚丙燃酰胺后制得复合粘结剂，这种复合粘结剂不仅防水，而且使型煤的强度得到进一步提高，具有实用前景。     

Options analysis for long-term capacity design and operation of a lignocellulosic biomass refinery

The growth of the lignocellulosic fuels has been hindered by technological and market uncertainty. This paper optimizes strategic investment decisions by prospective biobased fuel and chemical enterprises. A real options-based stochastic integer programming model is developed in this paper. We model a hypothetical, vertically integrated lignocellulosic enterprise that produces cellulosic ethanol and biosuccinic acid. Uncertainty is represented in bioproduct demands and prices. Strategic options including investment in research and development, investments in a flexible production platform and deferral of project investment are modeled. A hypothetical market model is also developed to correlate crude oil prices with the evolution of bioproduct markets. The discounted value of equity free cash flows is optimized. The optimal results include multiple capacity design plans based on the long term evolution of bioproduct markets. Monte Carlo simulations are also conducted to quantify the risk adjusted NPV's and returns on investment for the optimal capacity design trajectories.     

Modeling the thermochemical degradation of biomass inside a fast pyrolysis fluidized bed reactor

A fast pyrolysis process in a bubbling fluidized bed has been modeled, thoroughly reproduced and scrutinized with the help of a combined Eulerian/Lagrangian simulation method. The 3‐D model is compared to experimental results from a 100 g/h bubbling fluidized bed pyrolyzer including such variables as particle composition at the outlet and gas/vapor/water yields as a function of fluidization conditions, biomass moisture concentrations, and bed temperatures. Multiprocessor simulations on a high‐end computer have been carried out to enable the tracking of each of the 0.8 million individual discrete sand and biomass particles, making it possible to look at accurate and detailed multiscale information (i.e., any desired particle property, trajectory, particle interaction) over the entire particle life time. The overall thermochemical degradation process of biomass is influenced by local flow and particle properties and, therefore, accurate and detailed modeling reveals unprecedented insight into such complex processes. It has been found, that the superficial fluidization velocity is important while the particle moisture content is less significant for the final bio‐oil yield. © 2011 American Institute of Chemical Engineers AIChE J, 58: 3030–3042, 2012     

Apparatus Prototype for Purposes of Teaching in Bio-digesters

A mathematical model is developed based on a simplified mechanism of anaerobic digestion. The main objective is to quantitatively analyze the digestion process to optimize operating conditions and maintenance of this equipment, which could be used to test different materials and be able to apply these results to the possible scaling to bio-digesters installed in the field. The experiments were carried out in a hybrid system bio-digester photovoltaic cells. The bio-digester is made of stainless steel with dimensions to treat an average of 10 kg of raw material and produce biogas from different organic materials. The reactor has been conditioned with temperature sensors, pressure and methane gas that allow monitoring the concentration of the gas and the conditions of operation during the time of digestion. The system has a photovoltaic array to provide the energy required to keep the temperature constant, The experiment was conducted using materials such as goat manure mixed with household waste, and various formulations of these materials were prepared. The experimental results were used to test the mathematical model.     

生物质流化床腐蚀特性及抑制方法综述

生物质燃料具有水分、挥发分、碱金属含量较高、热值偏低的特点,适合流化床燃烧应用,但在燃烧过程中挥发出的碱金属和Cl元素在一定温度下会对流化床锅炉安全经济运行造成威胁,如Cl元素的挥发容易导致受热面腐蚀。其腐蚀类型可分为气相腐蚀、液相腐蚀和固相腐蚀,腐蚀程度主要受到燃料成分、温度的影响。本文针对生物质循环流化床锅炉受热面发生腐蚀的关键因素Cl成分,阐述了生物质循环流化床锅炉发生腐蚀现象的机理,根据工程实践,指出了实际锅炉发生腐蚀的现象及工程应对方法,并提出防止腐蚀可以在生物质燃料预处理、炉膛密相区附近增加二次风管、改变过热器受热面布置方式、加入特定成分添加剂以及受热面材质选择等方面进行突破,以期为生物质循环流化床锅炉的高可靠性运行提供指导。     

木质素解聚和液相催化降解研究进展

木质纤维生物质作为地球上最丰富的可再生资源, 不仅储量巨大而且在利用过程中具有碳平衡的显著优势, 已逐渐成为最具发展前景的可再生能源之一。木质纤维中的木质素是自然界最大且唯一的可再生芳香族化合物原料, 在生物质燃料转化, 尤其是解聚生产苯系化工产品等领域具有极为重要的作用和意义。本文在简述木质素化学结构的基础上, 综述了近年来木质素高温热解聚, 生物酶解聚, 催化热解聚, 光催化解聚和溶剂热解聚等解聚方法, 深入分析了液相催化过程中酸、碱催化体系, 加氢和氧化催化体系的机理及优缺点, 总结了现阶段木质素解聚方法中存在的问题, 并对未来的发展方向进行了展望。     

规模化连续生物质炭化设备的评价及产品分析

针对目前国内生物质废弃物热解炭化设备规模化生产中存在着生产设备运行不稳定、秸秆炭化产率低、副产品回收利用难等问题,采用稻壳和玉米秸秆成型颗粒为原料,研究其在该套规模化连续生物质炭化设备中长时间连续炭化情况,从而系统分析了该生物质炭化设备的适用性和稳定性。该设备由炭化单元、气体分离单元和出炭单元组成,炭化单元采用双层套筒结构,内层为炭化室,外层为燃气加热室,将生物质炭化产生的高热值生物质气回收后燃烧加热实现热解炭化过程的连续运行。实验结果表明：该生物质炭化设备设计合理,可满足不同原料炭化,可实现稻壳和玉米秸秆颗粒的长时间连续稳定炭化,炭化产能可达到490 kg/h,炭化温度控制在500 ℃左右,生物质炭的得率在37%以上,热解后固、液、气三相分离完全,气体得到循环利用。     

木耳碳基硫化钴复合材料的制备及电化学性能研究

以木耳制备的均匀溶液为碳源,加入ZIF-67前驱体,通过水热合成和高温煅烧制备氮硫共掺杂的木耳碳与硫化钴多孔片层复合材料（CoS/NSAC）。实验结果表明,该材料具有大的比表面积和高导电性,电化学性能良好。CoS/NSAC在电流密度为0.5 A/g时比容量达到484.8 F/g,在20 A/g高电流密度下循环5 000次容量保持率为78.8%。用该材料组装的非对称超级电容器具有优异的电化学性能,在0.6 A/g电流密度下比容量为154 F/g。当功率密度为362.3 W/kg时,能量密度为7.4 W?h/kg,经过1 800次循环容量保持率为81.95%。     

催化型多孔陶瓷球制备及催化玉米秸秆热解

针对生物质热解液化过程中生物油品质差的问题,本文以陶瓷球作热载体为研究基础,制备了5种负载金属氧化物（ZnO、NiO、CeO₂、Cr₂O₃、Fe₂O₃）的多孔陶瓷球,在固定床反应器上研究多孔陶瓷球催化剂对玉米秸秆热解过程的催化效果。结果表明：多孔陶瓷球基体在热解过程中有一定催化活性,经浸渍改性处理后,都能促进生物油产率的提高,其中Ni基多孔陶瓷球热解的产率高达41.62%。多孔陶瓷球负载的5种金属氧化物可促使生物油中酚类、呋喃类物质的含量明显增加,酸类物质的含量明显降低,且种类减少,其中CeO₂降酸效果显著,降低幅度为37.15%。此外,催化型多孔陶瓷球的引入促进了不可冷凝气中C _n H _m （n≥2）的生成,烯烃类中乙烯的增长幅度最大,为50.53%,同时生物炭的理化特性在一定程度上得到改善和提高。