生物质循环流化床锅炉烟气脱硝研究进展

介绍了生物质燃料及生物质循环流化床锅炉特点,以及生物质燃烧过程中NOX生成机理.综述了当前国内应用较广的生物质脱硝技术,结合生物质循环流化床锅炉及烟气特性,提出低氮燃烧+SNCR脱硝工艺、SNCR+低尘布置SCR工艺较为适合生物质循环流化床锅炉NOX减排.     

生物质成型燃料(BMF)技术

由广州迪森热能技术股份有限公司开发的生物质成型燃料(BMF),可替代燃料油、天然气等化石能源应用于民用及工业锅炉的燃烧。主要技术内容一、基本原理生物质成型燃料(Biomass Pellet or Biomass Moulding     

适于区域生物质特性的生物质气化技术的研究进展

基于我国生物质综合利用行业发展现状分析,进行生物质发电、生物沼气、生物质成型燃料以及生物液体燃料的市场发展前景和技术发展趋势的综合比较,进而聚焦于生物质气化技术,梳理出其主体发展路线研究进展,结合区域生物质特性,总结出最适于当地生物质特性的生物质气化发展技术,从而进一步推进生物质能行业发展和技术开发。     

秸秆成型燃料与垃圾衍生燃料混合燃烧研究

生物质成型燃料和垃圾衍生燃料均是20世纪后期兴起的新型能源利用技术。低碳、环保的燃烧特性和可再生属性使其具有巨大的发展潜力,成为21世纪替代化石燃料潮流中的优先选择之一。文章对生物质秸秆成型燃料和垃圾衍生燃料RDF-5的燃烧效率进行了研究,由工业焚烧试验得到的燃烧技术指标对比和经济、社会效益分析,得出生物质秸秆成型燃料和垃圾衍生燃料混合燃烧的燃烧效率高于垃圾衍生燃料单独燃烧效率的结论。     

基于利益相关者的农村新能源可持续性分析

对山东省即墨市＂秸秆成型燃料及配套炉具示范推广项目＂实地调研发现,配套生物质炉推广后秸秆成型燃料的使用情况并不理想。根据利益相关者理论分别对农户、企业和政府进行成本-收益分析,得知秸秆成型燃料的质量差和价格高是限制农民使用的主要因素,而销售量的萎缩则直接导致压块企业难以运营。提出地方政府层面应注重对成型燃料的宣传和生产市场的引导,可考虑在推广期进行价格补贴;国家层面应重视生物质能源共性技术研发,制定相关技术和行业标准,实行一定的政策倾斜。     

生物质合成二甲醚的技术经济分析

能源与环境安全引发了世界范围内替代能源的开发热。二甲醚（DME）燃料性能优秀,安全无毒,兼容性好,能通过生物质合成,因此成为备受关注的可再生替代能源。通过对利用云南省生物质资源合成DME进行技术经济分析,以及对二甲醚成本的敏感性分析表明,运输费用和秸秆收购价格影响二甲醚的售价和投资利润率。计算结果表明,利用生物质制取二甲醚具有可竞争性。     

DZL型生物质颗粒燃料工业锅炉

由北京盛昌绿能科技有限公司开发的DZL型生物质颗粒燃料工业锅炉,适用于工业生产、供暖、洗浴锅炉。主要技术内容适用生物质颗粒燃料的新型锅炉,本体采用新型锅壳锅炉结构,由纵置的锅筒、左右下集箱、炉膛水冷壁、烟道水冷壁、螺纹烟管及下降管等组成;燃烧     

解耦燃烧技术

由北京九州格物过程技术有限公司、中国科学院过程工程研究所共同开发的解耦燃烧技术，适用于中小型燃煤或生物质燃料设备。     

生物质"颗粒"燃料及气化燃烧锅炉

由大连鑫宝生物质能有限公司开发的生物质能“颗粒”燃料及气化燃烧锅炉，适用于生物质“颗粒”燃料及颗粒加工的机械设备和自动生产线。     

麦类秸秆燃料灰分与组成元素相关性分析研究

生物质燃料灰分含量高易引起在锅炉内结渣,影响锅炉运行效率,预测灰分含量对锅炉条件控制和选型有着重要意义。研究了小麦秸秆生物质灰分含量与组成元素含量的相关性,建立了基于灰分预测的多元线性回归模型,根据组成元素含量预测麦类秸秆生物质燃料的灰分。结果表明,组成元素均与灰分含量有显著的相关性,其中氧含量与灰分含量呈正相关,其他元素均呈负相关关系。灰分预测与实测值平均绝对误差为9.0%。通过上述研究发现,本研究建立的多元线性回归预测模型可以在一定程度上预测麦类秸秆生物质燃料灰分含量。     

Processing of Straw/Corn Stover: Comparison of Life Cycle Emissions

The LCA emissions from four renewable energy routes that convert straw/corn stover into usable energy are examined. The conversion options studied are ethanol by fermentation, syndiesel by oxygen gasification followed by Fischer Tropsch synthesis, and electricity by either direct combustion or biomass integrated gasification and combined cycle (BIGCC). The greenhouse gas (GHG) emissions of these four options are evaluated, drawing on a range of studies, and compared to the conventional technology they would replace in a western North American setting. The net avoided GHG emissions for the four energy conversion processes calculated relative to a “business as usual” case are 830 g CO₂e/kWh for direct combustion, 839 g CO₂e/kWh for BIGCC, 2,060 g CO₂e/L for ethanol production, and 2,440 g CO₂e/L for FT synthesis of syndiesel. The largest impact on avoided emissions arises from substitution of biomass for fossil fuel. Relative to this, the impact of emissions from processing of fossil fuel, e.g., refining of oil to produce gasoline or diesel, and processing of biomass to produce electricity or transportation fuels, is minor.     

Life cycle assessment of waste paper management: The importance of technology data and system boundaries in assessing recycling and incineration

The significance of technical data, as well as the significance of system boundary choices, when modelling the environmental impact from recycling and incineration of waste paper has been studied by a life cycle assessment focusing on global warming potentials. The consequence of choosing a specific set of data for the reprocessing technology, the virgin paper manufacturing technology and the incineration technology, as well as the importance of the recycling rate was studied. Furthermore, the system was expanded to include forestry and to include fossil fuel energy substitution from saved biomass, in order to study the importance of the system boundary choices. For recycling, the choice of virgin paper manufacturing data is most important, but the results show that also the impacts from the reprocessing technologies fluctuate greatly. For the overall results the choice of the technology data is of importance when comparing recycling including virgin paper substitution with incineration including energy substitution. Combining an environmentally high or low performing recycling technology with an environmentally high or low performing incineration technology can give quite different results. The modelling showed that recycling of paper, from a life cycle point of view, is environmentally equal or better than incineration with energy recovery only when the recycling technology is at a high environmental performance level. However, the modelling also showed that expanding the system to include substitution of fossil fuel energy by production of energy from the saved biomass associated with recycling will give a completely different result. In this case recycling is always more beneficial than incineration, thus increased recycling is desirable. Expanding the system to include forestry was shown to have a minor effect on the results. As assessments are often performed with a set choice of data and a set recycling rate, it is questionable how useful the results from this kind of LCA are for a policy maker. The high significance of the system boundary choices stresses the importance of scientific discussion on how to best address system analysis of recycling, for paper and other recyclable materials.     

Comparative Life Cycle Assessment of Lignocellulosic Ethanol Production: Biochemical Versus Thermochemical Conversion

Lignocellulosic biomass can be converted into ethanol through either biochemical or thermochemical conversion processes. Biochemical conversion involves hydrolysis and fermentation while thermochemical conversion involves gasification and catalytic synthesis. Even though these routes produce comparable amounts of ethanol and have similar energy efficiency at the plant level, little is known about their relative environmental performance from a life cycle perspective. Especially, the indirect impacts, i.e. emissions and resource consumption associated with the production of various process inputs, are largely neglected in previous studies. This article compiles material and energy flow data from process simulation models to develop life cycle inventory and compares the fossil fuel consumption, greenhouse gas emissions, and water consumption of both biomass-to-ethanol production processes. The results are presented in terms of contributions from feedstock, direct, indirect, and co-product credits for four representative biomass feedstocks i.e., wood chips, corn stover, waste paper, and wheat straw. To explore the potentials of the two conversion pathways, different technological scenarios are modeled, including current, 2012 and 2020 technology targets, as well as different production/co-production configurations. The modeling results suggest that biochemical conversion has slightly better performance on greenhouse gas emission and fossil fuel consumption, but that thermochemical conversion has significantly less direct, indirect, and life cycle water consumption. Also, if the thermochemical plant operates as a biorefinery with mixed alcohol co-products separated for chemicals, it has the potential to achieve better performance than biochemical pathway across all environmental impact categories considered due to higher co-product credits associated with chemicals being displaced. The results from this work serve as a starting point for developing full life cycle assessment model that facilitates effective decision-making regarding lignocellulosic ethanol production.     

Life cycle assessment of waste paper management: The importance of technology data and system boundaries in assessing recycling and incineration

The significance of technical data, as well as the significance of system boundary choices, when modelling the environmental impact from recycling and incineration of waste paper has been studied by a life cycle assessment focusing on global warming potentials. The consequence of choosing a specific set of data for the reprocessing technology, the virgin paper manufacturing technology and the incineration technology, as well as the importance of the recycling rate was studied. Furthermore, the system was expanded to include forestry and to include fossil fuel energy substitution from saved biomass, in order to study the importance of the system boundary choices. For recycling, the choice of virgin paper manufacturing data is most important, but the results show that also the impacts from the reprocessing technologies fluctuate greatly. For the overall results the choice of the technology data is of importance when comparing recycling including virgin paper substitution with incineration including energy substitution. Combining an environmentally high or low performing recycling technology with an environmentally high or low performing incineration technology can give quite different results. The modelling showed that recycling of paper, from a life cycle point of view, is environmentally equal or better than incineration with energy recovery only when the recycling technology is at a high environmental performance level. However, the modelling also showed that expanding the system to include substitution of fossil fuel energy by production of energy from the saved biomass associated with recycling will give a completely different result. In this case recycling is always more beneficial than incineration, thus increased recycling is desirable. Expanding the system to include forestry was shown to have a minor effect on the results. As assessments are often performed with a set choice of data and a set recycling rate, it is questionable how useful the results from this kind of LCA are for a policy maker. The high significance of the system boundary choices stresses the importance of scientific discussion on how to best address system analysis of recycling, for paper and other recyclable materials.     

Biomass use in chemical and mechanical pulping with biomass-based energy supply

The pulp and paper industry is energy intensive and consumes large amounts of wood. Biomass is a limited resource and its efficient use is therefore important. In this study, the total amount of biomass used for pulp and for energy is estimated for the production of several woodfree (containing only chemical pulp) and mechanical (containing mechanical pulp) printing paper products, under Swedish conditions. Chemical pulp mills today are largely self-sufficient in energy while mechanical pulp mills depend on large amounts of external electricity. Technically, all energy used in pulp- and papermaking can be biomass based. Here, we assume that all energy used, including external electricity and motor fuels, is based on forest biomass. The whole cradle-to-gate chain is included in the analyses. The results indicate that the total amount of biomass required per tonne paper is slightly lower for woodfree than for mechanical paper. For the biomass use per paper area, the paper grammage is decisive. If the grammage can be lowered by increasing the proportion of mechanical pulp, this may lower the biomass use per paper area, despite the higher biomass use per unit mass in mechanical paper. In the production of woodfree paper, energy recovery from residues in the mill accounts for most of the biomass use, while external electricity production accounts for the largest part for mechanical paper. Motor fuel production accounts for 5–7% of the biomass use. The biomass contained in the final paper product is 21–42% of the total biomass use, indicating that waste paper recovery is important. The biomass use was found to be about 15–17% lower for modelled, modern mills compared with mills representative of today's average technology.     

The Effect of Local Biomass Projects on Energy Balance and GHG Emission: A Life Cycle Approach

Emerging attention has been given to the use of biomass in local areas for its contribution to reducing fossil fuel dependence and mitigating global warming. The objective of the present study is to develop a method that quantitatively assesses the effects of local biomass projects on fossil fuel consumption and greenhouse gas (GHG) emission. A practical method based on a life cycle approach is proposed and applied to a case of bioethanol project in Miyako Islands of Japan. The project is aiming to produce bioethanol from molasses within the islands, and to replace the entire gasoline consumed in the islands to E3 fuel (i.e., a mixture of 3% ethanol and 97% gasoline by volume). The assessment using the developed method revealed that, first, the complete shift from gasoline to E3 fuel allows for decreases in fossil fuel consumption and GHG emission. Second, the performance of the project is improved by the integration of the ethanol plant and the sugar factory. Moreover, the assessment found that, in small-scale bioethanol projects, the contribution of capital goods to life cycle fuel consumption and GHG emission is not negligible.     

The role of electricity in sustainable development

Current projections estimating world population growth read in conjunction with corresponding projections of increased world energy consumption, point to electricity as the cleaner fuel of the future, especially because of its high efficiency and low levels of pollution. Due mostly to the fact that the electrical end-use devices are considerably more efficient than those using other forms of energy, most developed countries show decreasing curves of energy intensity as technologies become more sophisticated and shift over to increased reliance on electricity. It is therefore argued in this article that a gradual shift away from fossil fuels to electricity is a promising possibility to bring down global air pollution and emissions of greenhouse gases to acceptable levels. Examples are given of greater efficiency achieved by electrification. Overall gains in energy efficiency from the change over from fossil fuels to electricity, are possible even in situations where the electricity is generated by fossil fuel combustion, despite the loss of primary energy in the conversion process. The article also presents electricity generating projects designed for developing countries and countries with economies in transition. The generation of electricity from the combustion of renewable sources (biomass waste), fossil fuels, and other innovative methods are outlined.     

Forest-based biomass supply potential and economics for the pellet production in Nepal

In the current study, the potential of forest-based biomass supply for the pellet production in Nepal is investigated. This study showed that about 2.76 million tonnes (Mt) biomass in the form of pellets are potentially available from forest-based biomass. Considering a processing capacity of 6 tonnes (t)/hr of a pellet plant, the production cost of the pellets was calculated to be $43.53/t. Pellets are generally used as fuel to produce thermal energy in industries, which helps to save the economy and the environment of the country.     

Biomass for Fuel Cells: A Technical and Economic Assessment

Fuel cells can be highly efficient energy conversion devices. However, the environmental benefit of utilising fuel cells for energy conversion is completely dependent on the source of the fuel. Hydrogen is the ideal fuel for fuel cells but the current most economical methods of producing hydrogen also result in the production of significant amounts of carbon dioxide. Utilising biomass to produce the fuel for fuel cell systems offers an option that is technically feasible, potentially economically attractive and greenhouse gas neutral. High-temperature fuel cells that are able to operate with carbon monoxide in the feed are well suited to these applications. Furthermore, because they do not require noble metal catalysts, the cost of high-temperature fuel cells has the greatest potential to become competitive in the near future compared to other types of fuel cells. It is, however, extremely difficult to assess the economic feasibility of biomass-fuelled fuel cell systems because of a lack of published cost information and uncertainty in the predicted cost per kW of the various types of fuel cells for large volume production methods. From the scant information available it appears that the current cost for fuel-cell systems operating on anaerobic digester gas is about US$2,500 per kW compared to a target price of US$1,200 required to compete with conventional technologies.     

Alternative energy: Environmental and economic factors associated with renewable energy and creating new integrated energy management systems

At best, the future of alternative and renewable energy remains uncertain. Our dependency on fossil fuels is already depleting world supplies of coal and petroleum while increasing greenhouse gas emissions. Most assuredly, the ability of alternative energy, described in this article as biomass, hydrogen, wind, solar, and geothermal power, to compete and even integrate with fossil fuels will depend on several important variables: First, developing, as well as developed, countries must be willing to direct long-term public and private funding towards innovative energy technologies by increasing research and promoting public education. Secondly, the “bottom line” economics associated with alternative energy technology must clearly show a positive cost/benefit ratio. Revenues and not deficits are paramount to the sustainability of alternative energy. Lastly, many experts argue for the environmental benefits of alternative energy by way of carbon reductions. The 1997 Kyoto Global Warming Treaty requires the United States in particular to reduce carbon dioxide emissions from fossil fuel burning by 7 percent below 1990 levels. While many experts argue that reactions to global warming and the alternative energy benefits anticipated because of them are fiscally irresponsible and not worth the billions of tax dollars intended, we can be assured that a business-as-usual attitude will continue without increased government and public support.© 1999 John Wiley & Sons, Inc.