我国户用生物质炉灶的发展和应用

回顾了我国户用生物质炉灶的发展历程,介绍了我国生物质炉灶的推广应用现状和技术水平,分析了生物质炉灶性能测试标准和评价方法;阐述了应用生物质炉灶技术开发CDM项目的发展现状、开发方法以及未来发展的巨大潜力;最后提出了生物质炉灶技术应用发展的建议。     

生物质炉灶技术创新和推广项目颁奖大会召开

2007年3月26～27日,“促进中国和国际高效低排放户用生物质炉灶技术创新和推广项目”颁奖大会在北京农招大酒店召开。     

中、美、印3国生物质炉灶测试方法比较研究

清洁能源的高效利用是国际关注的话题,研究和制定生物质炉灶的测试标准是生物质炉灶可持续发展的基础工作。文章对国际上主要的3种生物质炉灶性能测试方法进行了介绍,研究比较了操作程序、性能指标计算、污染排放测试与重复性测试等方面的差异,并从理论上分析了这些差异对测试结果产生的影响。根据分析比较结果,对我国的生物质炉灶性能测试标准提出了改进建议。     

壳牌基金会生物质炉灶项目的实施及其意义

由壳牌基金会提供经费支持，农业部有关部门批准实施的“促进中国和国际高效低排放户用生物质炉灶技术创新和推广”项目，近日由中国农村能源行业协会节能炉具专业委员会和美国加利福尼亚大学伯克力分校国际健康与发展企业家中心合作完成，并于6月18日通过项目专家组的评审鉴定。     

发展中国家农村民用炉灶的温室气体和污染物排放因子研究

在发展中国家，农村民用炉灶是消耗生物质能的主要设备。为了确定民用炉灶的温室气体和其它污染物的排放因子，从上世纪90年代开始，国际社会选择中国、印度等发展中国家进行了一系列测试。文中对这些测试结果进行了总结和比较。研究表明，除了个别燃料和炉灶组合，生物质能源在节能炉灶中的CO2排放因子都有所降低，而不完全燃烧产物的排放因子比传统炉灶高。     

生物质炉传热性能及结构的研究

采用有限元方法,对SY40型生物质炉的传热过程进行模拟。研究了生物质炉的工艺参数和结构参数对传热效率的影响,并根据研究结果,对生物质炉结构进行改进。     

上燃均衡供氧式生物质成型燃料炊事炉的设计与性能测试

为提高农村用能效率,依据生物质燃烧特性和热工计算标准,设计上燃均衡供氧式生物质成型燃料炊事炉。确定炊事炉的主要设计参数,构建相互独立的螺旋式分级配风系统及灰仓与风管相结合的自然进风系统,并对炊事炉的性能进行测试。结果显示炊事炉热效率为40.25%,炊事火力强度为3.32 kW,烟尘、CO、SO_2、NO_x等烟气污染物排放均符合国家相关标准,可保证成型颗粒燃料的充分燃烧,提高燃烧性能。     

电炉模拟生物质炊事炉具热效率测试的影响因素研究

生物质能源的清洁利用作为解决能源短缺的有效途径,受到了国际上越来越多的关注。目前世界各国对于生物质炉具热效率测试方法和程序不尽相同,为了研究比较不同的测试方法对生物质炉具热效率测试结果的影响,利用电炉模拟生物质炉具,采用不同的测试程序和方法测试其热性能,并对测试结果进行分析比较。分析测试结果表明,蒸发锅中的不同水量、闭盖/无盖对热效率的测试结果有一定影响,同时根据分析研究结果,针对我国目前生物质炊事炉具热效率的测试方法提出了改进建议。     

家用生物质颗粒燃料炉的研制

为解决农村秸秆焚烧污染问题，研究以生物质颗粒为燃料的家用生物质颗粒燃料炉供农家炊事使用。在充分研究、分析生物质颗粒燃料燃烧动力学特性的基础上，根据生物质颗粒燃料挥发分含量高、燃点低的特点，在生物质颗粒燃料炉的设计中采用了气化、燃烧一体化结构。测试结果表明，生物质颗粒燃料在生物质颗粒燃料炉内能气化燃烧，残碳也能够完全燃尽。该炉的主要技术指标均符合国家标准，燃烧稳定、高效、清洁，提高了秸秆的能源利用率。     

户用生物质炉具热效率试验方法研究

针对国内外主要热效率试验方法进行对比与研究,通过控制试验操作方法及条件,得出6组影响因素,对实测热效率结果进行了评价。尝试找出适用于国内户用生物质炉具的试验方法,且使操作更加便捷,测试结果更加准确。     

上吸式生物质秸秆气化炉的设计与试验研究

设计一台上吸式生物质秸秆气化炉,并进行热解气化试验,分析不同气化剂量对炉内温度的影响以及温度和秸秆种类对产气成分的影响。试验结果表明：气化剂量对炉内温度及炉内温度对产气成分含量的影响均较大;秸秆种类也对产气的热值有较大的影响,稻草热解可燃气热值4．1MJ／m^3,油菜秆热解可燃气热值4．9MJ／m^3,玉米秆热解可燃气热值5．5MJ／m^3。     

小型生物质气化发电系统的设计与测试

对小型生物质气化发电系统进行了设计和测试分析,阐述了以农作物秸秆为原料的小型生物质气化发电系统的技术可行性,总结出分散式的生物质能利用模式具有投资少、见效快并且易于操作和管理等优点,认为在未来一段时间内,该系统的推广、应用具有一定的可行性和优越性。     

玉米秸秆两级CSTR厌氧消化工艺动力学性能研究

文章采用物料衡算模型、微生物衡算模型和一级动力学模型对两级CSTR厌氧消化系统的运行性能进行了研究。研究结果表明:两级厌氧消化系统HRT(20+20)d和HRT(30+10)d的产甲烷系数分别比单级厌氧消化系统HRT40d增加了5.38%和5.99%;HRT(20+20)d和HRT(30+10)d的第一级反应器的一级动力学常数高于HRT40d以及HRT(20+20)d和HRT(30+10)d的第二级反应器的一级动力学常数;HRT40d,HRT(20+20)d和HRT(30+10)d的微生物产率系数分别为0.003 8,0.016 6和0.020 4;在不同有机负荷率下,HRT(20+20)d,HRT30+10d和HRT40d的平均微生物浓度分别为0.221~0.350,0.275~0.447,0.047~0.076 g/L。     

燃烧生物质成型燃料采暖热风炉的设计与试验

为弥补华北农村冬季传统采暖存在的不足,根据生物质成型燃料燃烧特性,设计制造出适合燃用生物质成型燃料的专用热风采暖炉,并对其进行了热工性能试验,结果表明,在较好工况下,其燃烧效率可达85.03％～92.06％,热效率可达44．82％～55．85％,为解决农村地区采暖问题提供了有效途径。     

Production costs of potential corn stover harvest and storage systems

Corn stover has potential as a bioenergy feedstock in North America. We simulated production costs for stover harvest (three-pass and two-pass with baling or chopping, and single-pass with baling or chopping) and on-farm storage (outdoor and indoor bales, outdoor wrapped bales, and chopped stover in bags, bunks, or piles). For three- and two-pass harvest, chopping was 33–45% more expensive than baling. For baling and chopping, two-pass harvest was 25% cheaper than three-pass. Single-pass chopping harvests were on average 42% cheaper than three-pass or two-pass chopping. Single-pass baling was cheaper (4–31%) than multi-pass baling at low rates of stover collection, but more expensive (1–39%) at high rates of collection. For bales, outdoor storage of wrapped bales was cheapest. Outdoor, unwrapped bale storage, even with 12% dry matter loss, was cheaper than indoor storage. For chopped stover, storage in bags was always cheapest, followed by piles, and then bunkers. With harvest and storage together, there were four least cost systems: single-pass, ear-snap baling with wrapped bale storage; single-pass chopping with silage bag storage; and two-pass baling with wrapped-bale storage. A second group of harvest/storage systems was 25% more expensive, including single-pass, whole-plant baling with wrapped-bale storage; two-pass chopping with silage-bag storage; and three-pass baling with wrapped-bale storage. The three-pass chop harvest with silage bag storage was most expensive. Our analysis suggests all harvest and farm storage systems have tradeoffs and several systems can be economically and logistically viable.     

Perspectives for the direct firing of biomass as a supplementary fuel in combined cycle power plants

An analysis of the performance of a gas turbine–steam turbine combined cycle with supplementary firing has been carried out. Natural gas is fired in the main combustor of the cycle, whereas biomass fuel is considered as the supplementary fuel. Although, supplementary firing is found to reduce the overall cycle efficiency, the low cost of biomass and the CO₂‐neutral attribute of its combustion reduce the specific fuel cost and specific CO₂ emission. The effects of pressure and temperature ratios of the topping cycle and main steam conditions of the bottoming cycle on the performance parameters of the combined cycle have been studied at different degrees of supplementary firing. The topping cycle temperature ratio is found to be the most critical parameter and its low value gives substantial advantages in lowering the fuel cost and CO₂ emission. Marginal advantages are also achieved at higher pressure ratio and better bottoming cycle main steam conditions. Copyright © 2008 John Wiley & Sons, Ltd.     

对9FA燃气轮机联合循环机组性能试验的思考

对9FA燃机联合循环性能试验中的一些问题进行了分析,如性能的修正、余热锅炉的性能考核、责任分摊等,并给出了作者的看法,供同行参考。     

Periodic peristalsis enhancing the high solids enzymatic hydrolysis performance of steam exploded corn stover biomass

Enzymatic hydrolysis beyond 15% solid loading offers many advantages such as increased sugar and ethanol concentrations and decreased capital cost. However, difficult mixing and handling limited its industrialized application. A novel intensification method, periodic peristalsis, had been exploited to improve the high solids enzymatic hydrolysis performance of steam exploded corn stover (SECS). The optimal steam explosion conditions were 200 °C and 8 min, under which glucan and xylan recovery was 94.3% and 64.8%, respectively. Glucan and xylan conversions in periodic peristalsis enzymatic hydrolysis (PPEH) were 28.0–38.5% and 25.0–36.0% higher than those in static state enzymatic hydrolysis with solid loading increasing from 1% to 30%, respectively, while they were 1.0–11.2% and 3.0–9.2% higher than those in incubator shaker enzymatic hydrolysis (ISEH). Glucan and xylan conversion in PPEH at 21% solid loading reached 71.2% and 70.3%, respectively. Periodic peristalsis also facilitated fed-batch enzymatic hydrolysis of which SECS was added completely before transition point. Results presented that PPEH shortened the transition point time from solid state to slurry state, decreased the viscosity of hydrolysis mixture, and reduced the denaturation effect of enzymes compared with ISEH, and hence improve the high solids enzymatic hydrolysis efficiency.