生物质颗粒燃料灰行为研究进展

本文综述生物质颗粒燃料产业现状及生物质颗粒燃料的灰行为研究现状,分析了生物质颗粒燃料灰行为的研究前景,指出随着生物质颗粒燃料的灰行为问题的解决,生物质颗粒燃料必将成为我国未来新型能源的重要组成部分。     

生物质颗粒燃料燃烧设备的研究进展

生物质颗粒燃料是一种优质的清洁燃料,可替代煤炭等化石燃料,广泛应用于炊事、供暖等民用领域和锅炉燃烧、发电等工业领域.文章简述了生物质颗粒燃料的燃烧特性,分析了国内外生物质颗粒燃料燃烧设备的研究进展及应用现状,对3种类型的生物质颗粒燃料燃烧器、进料系统、控制系统、清灰装置以及污染物排放等进行比较,最后指出了目前燃烧器存在的主要问题,并提出了我国生物质颗粒燃料燃烧设备的发展方向.     

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。     

沈阳市发展生物质颗粒燃料的制约因素和对策研究

阐述了沈阳市推广生物质颗粒燃料的必要性及重要意义,分析了生物质颗粒燃料在沈阳市推广应用过程中存在的问题,并针对这些问题提出了一系列解决方法与对策.对生物质颗粒燃料的商品化和大规模利用进行了展望,指出生物质颗粒燃料在沈阳地区具有良好的发展前景.     

生物质颗粒燃料燃烧模拟实验

在生物质颗粒燃料燃烧试验用锅炉平台上,进行了多种配风、一、二次风配比、不同的二次送风位置及改变燃料层厚度四个工况下的实验研究。实验结果表明：生物质颗粒燃料锅炉热效率高达77.69%,而锅炉排烟中NOX、SO2等环保指标远远低于燃煤锅炉。燃烧模拟实验为生物质颗粒锅炉设计和运行提供规律性参考数据。     

燃煤链条锅炉改燃生物质颗粒燃料的方案研究

生物质颗粒燃料取代常规煤燃料对节约常规能源、优化我国能源结构、减轻环境污染具有积极的意义。生物质颗粒燃料与常规煤燃料的特性有较大的区别。当将燃煤锅炉改造为燃生物质颗粒燃料锅炉时应采取相应的改造措施。以本公司锅炉为实例对燃煤链条锅炉的炉膛和燃烧系统进行了改造,通过对炉拱、炉排、风室、卫燃带、上料系统、燃烧控制系统进行改造实现了锅炉与生物质颗粒燃料燃烧的良好匹配。能效和环保测试结果表明,锅炉改燃生物质颗粒燃料后热效率提高,污染物排放符合标准要求。     

生物质就地及时压缩成型技术——Highzones技术

生物质能源在可再生能源中占有举足轻重的地位。大量、高效地利用生物质能源,尤其是我国的秸秆类农业生产废弃物,一直是生物质能利用技术研究开发的重点方向。一种全新的生物质颗粒燃料成型技术(Highzones技术)已由北京惠众实科技有限公司开发成功,在生物质燃料成型技术领域获得了突破性进展。2004年,经过瑞典农业大学生物质技术与化学研究所严格的系统测试,证明Highzones技术的性能优于国际上现有的颗粒成型技术。Highzones的发明可使生物质颗粒燃料的成型设备具有紧凑、经济、安全的特点,便于在生物质原料产地推广使用。通过进一步开发,颗粒燃料成型机还可以与联合收割机配套,实现同时收获粮食与秸秆颗粒燃料。Highzones技术能够消除生物质燃料规模化应用中存在的收、运、储成本高这一"瓶颈"问题,从而使生物质颗粒燃料进入商业化燃料市场,最大可能地替代化石能源。Highzones技术的应用和推广,可使形成一条生物质颗粒燃料生产与消费的产业链,对缓解我国能源紧张、减少二氧化碳排放、促进Z生态绿化产业发展,以及扩大农村就业、增加农民收入和改善其生活条件,将发挥重要作用。     

生物质锅炉优化燃烧研究

通过对典型生物质颗粒燃料及锅炉热效率研究分析,提出了优化生物质颗粒燃料锅炉燃烧和提高锅炉热效率的措施。     

瑞典生物质颗粒燃料产业发展现状与经验

瑞典是世界上最大的生物质颗粒燃料生产国和消费国,其在颗粒燃料技术研发、产业政策和市场运行模式等方面已走在世界前列。2008年,瑞典生物质颗粒燃料消耗量达到185万t,颗粒燃料产业取得了巨大发展。文章通过对瑞典颗粒燃料产业现状、政策、燃烧技术以及质量保障体系等进行系统分析,总结了瑞典颗粒燃料产业的发展经验,为我国成型燃料产业提供政策建议,将有利于我国成型燃料的推广与应用。     

生物质颗粒燃料冷成型技术试验研究

对环模生物质颗粒燃料成型机影响成型的各主要因素进行了分析及试验研究,给出不同生物质原料、粒度、含水率、环模孔长径比等因素与颗粒成型率及吨料电耗的关系,找出生物质颗粒燃料的最佳成型条件。     

燃生物质颗粒工业锅炉系统的生命周期评价

为了研究生物质工业锅炉系统对环境影响和能源消耗情况,本文采用了生命周期(LCA)的研究方法,从该系统的原料生产制作,到系统建立运行进行全面分析。结果表明:处理每1 t生物质颗粒,对环境的总影响负荷为16 434.47毫人当量,资源耗竭系数为2.547毫人当量,燃生物质工业锅炉系统对环境影响主要为全球变暖为95.36%,各个过程中锅炉系统运行影响为98.55%,秸秆种植从环境中吸收CO22 136.24 kg,因此,燃生物质工业锅炉系统在减少温室气体排放上能起积极作用,与燃煤锅炉相比生物质锅炉是一种环境友好并且减少化石燃料消耗的项目。     

Economic sensitivity of wood biomass utilization for greenhouse heating application

This paper presents an analysis of the impacts of technical and market changes on the economic feasibility of using wood biomass to produce heat for an average-sized greenhouse in British Columbia. A previous techno-economic analysis determined that the installation of a wood pellet or a wood residue boiler to generate 40% of the greenhouse heat demand is more economical than using a natural gas boiler alone to generate all the heat [1]. As the techno-economic analysis contained forecasted parameters, a thorough sensitivity analysis is needed for sound decision making. This paper extends the previous techno-economic study by assessing the effect of fuel price, wood biomass energy contribution, and greenhouse size changes on the net present value (NPV) when using a wood pellet or wood residue boiler with or without an electrostatic precipitator (ESP). The results indicate that the attractiveness of using wood biomass will increase if the price of fossil fuels increases more than 3% per year or carbon taxes and regulations are applied. Increasing the biomass energy contribution by 20% (to provide 60% of the total heat demand) would still be economical. The installation of a wood pellet boiler or a wood residue boiler is economical for average (7.5 ha) or large (15 ha) greenhouses.     

生物质燃料在燃煤锅炉上直接燃烧的试验研究

在1台燃煤锅炉上进行了生物质燃料燃烧试验和与燃煤的对比试验。结果显示,燃煤锅炉须经改造才能适应生物质燃料。生物质燃料与燃煤比较,不论燃料性质、燃烧现象、结焦特性、对炉膛的要求等方面都不同。生物质燃料燃烧时出现了不低于1 300℃高温区域和较高的NOx排放,与文献报道差别较大。     

Techno-economic analysis of wood biomass boilers for the greenhouse industry

The objective of this study is to perform a techno-economic analysis on a typical wood pellet and wood residue boiler for generation of heat to an average-sized greenhouse in British Columbia. The variables analyzed included greenhouse size and structure, boiler efficiency, fuel types, and source of carbon dioxide (CO₂) for crop fertilization. The net present value (NPV) show that installing a wood pellet or a wood residue boiler to provide 40% of the annual heat demand is more economical than using a natural gas boiler to provide all the heat at a discount rate of 10%. For an assumed lifespan of 25 years, a wood pellet boiler system could generate NPV of C$259,311 without electrostatic precipitator (ESP) and C$74,695 with ESP, respectively. While, installing a wood residue boiler with or without an ESP could provide NPV of C$919,922 or C$1,104,538, respectively. Using a wood biomass boiler could also eliminate over 3000 tonne CO₂ equivalents of greenhouse gases annually. Wood biomass combustion generates more particulate matters than natural gas combustion. However, an advanced emission control system could significantly reduce particulate matters emission from wood biomass combustion which would bring the particulate emission to a relatively similar level as for natural gas.     

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.     

Experimental investigation of the primary combustion zone during staged combustion of wood-chips in a commercial small-scale boiler

In this work the primary combustion zone of a modified, commercial, small-scale boiler was investigated during staged combustion of wood-chips. Experimental research on thermal conversion of biomass in fixed beds is necessary to supply reliable data for gas phase combustion model validation and optimization. Furthermore, scruting of pollutant emission formation and combustion efficiency enhancement can be conducted. Two different fuel moistures were used while the primary combustion zone of a small-scale boiler was investigated as a function of the primary air ratio. The combustible products leaving the fuel layer were analyzed under continuous operation by an extractive method. This approach is new in the field of small-scale biomass combustion research and considers the strong coupling between the products leaving the fuel bed and the heat fluxes emitted by the flame of the secondary combustion zone. Additionally, fine particulate matter emissions were quantified to study the effect of varying primary air ratio and different fuel moisture on particulate formation. Results show that the primary air ratio and the fuel moisture have a significant influence on the primary combustion products composition, on the fuel bed behavior and on fine particulate matter emissions. At low primary air ratios, tars constitute a significant part of the heating value of primary combustion products. The smallest amount of particulate emissions was found at low primary air ratio and low fuel moisture. Experimental data was validated with an elemental balance, which showed perfect accordance.     

改进型固定床上吸式气化炉及其在蒸汽锅炉中的代油燃烧应用

在蒸汽锅炉进行生物质能源改造中,生物质气化燃气代替煤、油具有成本、环保、政策方面的优势,但必须解决焦油的二次污染问题。本文提出以改进型即中部出气固定床上吸式气化炉生产生物质可燃气,及焦油成分随燃气直接在锅炉炉膛燃烧的技术路线,并以2 T/h蒸汽锅炉为例对气化炉的主要结构参数进行设计计算。采用基于锅炉输出蒸汽压力的气化炉鼓风自适应控制方法实现系统的闭环控制。最后通过实际应用案例实测数据的热能计算证明生物质气化燃气在蒸汽锅炉中代替煤、油燃烧的可行性。     

Feasibility study of forest residue use as fuel through co-firing with pellet

Co-firing is a useful technology for reclaiming waste biomass as fuel. This article studies the use of three different forest residues (Eucalyptus, pine and pine bark) with pellet based on a mixture of fuels prior to combustion. Several combustion configurations, such as the basic configuration (only preheated primary air supply) and other especially developed configurations, such as secondary air and gas recirculation, are studied and optimized. Due to feeding problems, a co-firing feeding hopper was specially developed and honed in order to assure a precise feeding rate of different fuel materials. The experimental results suggest that the pine bark has the best feed performance. Overall, a lower efficiency was achieved compared with pellet-only combustion. Co-firing of these blends is financially viable due to the lower price of the treated pine bark. High percentages of pine bark (50%) reduce efficiency significantly. This is improved with secondary air and recirculation. Pine bark of around 25% is the most suitable configuration.