经济作物将替代粮食作乙醇汽油原料

[本刊讯]从日前在上海召开的生物柴油与生物质资源化工利用发展研讨会上获悉,国家将不再利用粮食作为生物质能源的生产原料,取代粮食的将是经济作物。这一消息是在国家发改委能源局可再生能源处处长史立山的发言报告中透露的。此消息当即引起众多想投资新生物能源领域企业代表的热切关注。替代产品是经济作物在发改委可再生能源处的报告中看到,发改委已做出了在山东、黑龙江、内蒙古和新疆等地的生物质燃料新原料生产基地的具体规划。燃料乙醇的新原料包括甜高粱、木薯、甘蔗等,而麻疯树、黄连木等油料植物则是用来生产生物柴油。发改委能源…     

生物燃料的工具一光生物反应器

从微藻中提炼生物燃料是有前景的,将成为一个新兴的替代能源。但是,由于生产成本昂贵、耗能高致使目前不能大规模商业化生产。这些问题被提到了最近的发展进程中。本文主要从有效混合、降低能耗和光稀释等方面着手讨论光生物反应器。这些努力使微藻生产生物燃料接近经济上的可行性,并且已在中试工厂试行。未来希望可以利用微藻来工业化生产生物燃料。     

甘蔗生产燃料乙醇的发展现状及前景展望

甘蔗是C4作物,其光能转换效率、光合速率、单位面积生物产量显著高于其他作物,其净能比最高。用甘蔗生产燃料乙醇,成本低。甘蔗是最有潜力的生物能源作物,但是我国发展生物能源必须重视能源甘蔗品种的选育,加强甘蔗燃料乙醇生产工艺的研究与开发。利用甘蔗发展燃料乙醇产业具有广阔的前景。分析了我国利用甘蔗发展可再生生物能源的必要性及可行性。     

生物柴油生产和利用的环境影响评价

生物柴油作为清洁的、可再生的石化燃料的替代能源,在许多国家得到了快速发展.通过生命周期评估法,对以油菜籽和大豆为原料的生物柴油生产全过程,包括种子的筛选、种植到生物柴油的燃烧,进行了环境影响评价,并与石化柴油进行了比较.     

中国生物能源产业正在形成

<正>中国生物能源等一批新兴产业正在形成,木薯、甜高梁等非粮原料制燃料乙醇产业化加快,一批生物柴油、秸秆发电项目正在建设,投资快速增长。中国将加大非粮原料生产生物能源的研究,加大对生物能源技术研究开发与产业化的投入,建立财政资金优先购买自主创新生物产品制度,对生物柴油、生物质发电和经批准生产的燃料乙醇等重要生物产品给予支持。     

欧盟通过新的生物燃料发展计划

<正>欧盟委员会于2005年12月7日通过一项旨在对林业、农业和废物中能源加强利用的行动计划。该计划规定20项具体行动,绝大多数行动从2006年开始实施。利用农作物生产生物燃料在该计划中占据十分重要地位,且将成为欧盟委员会2006年主要工作之一。欧盟于2006年春天要通过一项生物燃料决议,且在2006年下半年审查生物燃料指令。该计划要解决问题包括:各成员国生物燃料市场份额目标;生物燃料使用义务;建立一套验证体系,以确保只有按照最低可持续发展标准生产生物燃料才能纳入目标。     

我国发展生物燃料乙醇的长久大计

介绍了包括生物质能源在内的新能源开发和研究的迫切性和必要性,概述了第一代生物燃料乙醇遇到的危害粮食安全的问题,以及第二代生物燃料乙醇对于改变能源结构、保护生态环境、替代化石能源具有的前景和意义,并提出了我国发展第二代生物燃料乙醇的必要对策。     

欧盟确定发展生物燃料相关政策

欧盟把发展生物燃料，尤其是交通运输的生物燃料，作为解决地区能源和环境问题的重大战略。2006年最新的《欧盟生物燃料战略》，确立了发展生物燃料的目标和主要政策措施。发展生物燃料也是我国的现实选择，欧盟的有关政策措施对我国发展生物燃料产业有其借鉴意义。     

2013非粮生物质能源年会成功召开

2013年10月26日至27日,"2013非粮生物质能源年会"在北京召开。本次会议由国家能源生物液体燃料研发(实验)中心和国家能源非粮生物质原料研发中心主办,国家能源生物燃料研发中心和国家能源生物炼制研发中心协办。国家能源局能源节约和科技装备司领导莅临会场,并指导致辞!来自生物质能源行业的百余位专家、学者和企事业单位的研发工作人员参会。会议全方位、多层次介绍了非粮生物质能源行业动态和技术进展,报告内容丰富、信息及时准确,会场讨论热烈,为生物质能源行业各单位的交流合作提供了平台!     

中国非粮燃料乙醇发展现状及展望

为应对石化能源短缺的局面和节能减排的压力,可再生能源的开发和发展越来越受到中国政府的重视。介绍了我国可再生能源的中长期发展规划,其中明确:到2015年非粮原料燃料乙醇年利用量达400万吨;到2020年,生物燃料乙醇年利用量达1000万吨。重点分析了燃料乙醇发展中非粮原料(薯类、甜高粱、木质纤维素等)生产乙醇的发展现状及瓶颈问题,最后对非粮原料生产燃料乙醇的前景进行了展望。     

Operation of marine diesel engines on biogenic fuels: modification of emissions and resulting climate effects

The modification of emissions of climate-sensitive exhaust compounds such as CO(2), NO(x), hydrocarbons, and particulate matter from medium-speed marine diesel engines was studied for a set of fossil and biogenic fuels. Applied fossil fuels were the reference heavy fuel oil (HFO) and the low-sulfur marine gas oil (MGO); biogenic fuels were palm oil, soybean oil, sunflower oil, and animal fat. Greenhouse gas (GHG) emissions related to the production of biogenic fuels were treated by means of a fuel life cycle analysis which included land use changes associated with the growth of energy plants. Emissions of CO(2) and NO(x) per kWh were found to be similar for fossil fuels and biogenic fuels. PM mass emission was reduced to 10-15% of HFO emissions for all low-sulfur fuels including MGO as a fossil fuel. Black carbon emissions were reduced significantly to 13-30% of HFO. Changes in emissions were predominantly related to particulate sulfate, while differences between low-sulfur fossil fuels and low-sulfur biogenic fuels were of minor significance. GHG emissions from the biogenic fuel life cycle (FLC) depend crucially on energy plant production conditions and have the potential of shifting the overall GHG budget from positive to negative compared to fossil fuels.     

Land use greenhouse gas emissions from conventional oil production and oil sands

Debates surrounding the greenhouse gas (GHG) emissions from land use of biofuels production have created a need to quantify the relative land use GHG intensity of fossil fuels. When contrasting land use GHG intensity of fossil fuel and biofuel production, it is the energy yield that greatly distinguishes the two. Although emissions released from land disturbed by fossil fuels can be comparable or higher than biofuels, the energy yield of oil production is typically 2-3 orders of magnitude higher, (0.33-2.6, 0.61-1.2, and 2.2 5.1 PJ/ha) for conventional oil production, oil sands surface mining, and in situ production, respectively). We found that land use contributes small portions of GHGs to life cycle emissions of California crude and in situ oil sands production ( <0.4% or < 0.4 gCO?e/MJ crude refinery feedstock) and small to modest portions for Alberta conventional oil (0.1-4% or 0.1-3.4 gCO?e/MJ) and surface mining of oil sands (0.9-11% or 0.8-10.2 gCO?e/MJ).Our estimates are based on assumptions aggregated over large spatial and temporal scales and assuming 100% reclamation. Values on finer spatial and temporal scales that are relevant to policy targets need to account for site-specific information, the baseline natural and anthropogenic disturbance.     

Is cumulative fossil energy demand a useful indicator for the environmental performance of products?

The appropriateness of the fossil Cumulative Energy Demand (CED) as an indicator for the environmental performance of products and processes is explored with a regression analysis between the environmental life-cycle impacts and fossil CEDs of 1218 products, divided into the product categories "energy production", "material production", "transport", and "waste treatment". Our results show that, for all product groups but waste treatment, the fossil CED correlates well with most impact categories, such as global warming, resource depletion, acidification, eutrophication, tropospheric ozone formation, ozone depletion, and human toxicity (explained variance between 46% and 100%). We conclude that the use of fossil fuels is an important driver of several environmental impacts and thereby indicative for many environmental problems. It maytherefore serve as a screening indicatorfor environmental performance. However, the usefulness of fossil CED as a stand-alone indicator for environmental impact is limited by the large uncertainty in the product-specific fossil CED-based impact scores (larger than a factor of 10 for the majority of the impact categories; 95% confidence interval). A major reason for this high uncertainty is nonfossil energy related emissions and land use, such as landfill leachates, radionuclide emissions, and land use in agriculture and forestry.     

Appreciating the role of thermodynamics in LCA improvement analysis via an application to titanium dioxide nanoparticles

Although many regard it as the most important step of life cycle assessment, improvement analysis is given relatively little attention in the literature. Most available improvement approaches are highly subjective, and traditional LCA methods often do not account for resources other than fossil fuels. In this work exergy is evaluated as a thermodynamically rigorous way of identifying process improvement opportunities. As a case study, a novel process for producing titanium dioxide nanoparticles is considered. A traditional impact assessment, a first law energy analysis, and an exergy analysis are done at both the process and life cycle scales. The results indicate that exergy analysis provides insights not available via other methods, especially for identifying unit operations with the greatest potential for improvement. Exergetic resource accounting at the life cycle scale shows that other materials are at least as significant as fossil fuels for the production of TiO2 nanoparticles in this process.     

Assessing GHG emissions, ecological footprint, and water linkage for different fuels

Currently, transport is highly dependent on fossil fuels and responsible for about 23% of world energy-related GHG (greenhouse gas) emissions. Ethanol from sugar cane and corn emerges as an alternative for gasoline in order to mitigate GHG emissions. Additionally, deeper offshore drilling projects such as in the Brazilian Pre-Salt reservoirs and mining projects of nonconventional sources like Tar Sands in Canada could be a solution for supplying demand of fossil fuels in the short and midterm. Based on updated literature, this paper presents an assessment of GHG emissions for four different fuels: ethanol from sugar cane and from corn and gasoline from conventional crude oil and from tar sands. An Ecological Footprint analysis is also presented, which shows that ethanol from sugar cane has the lowest GHG emissions and requires the lowest biocapacity per unit of energy produced among these fuels. Finally, an analysis using the Embodied Water concept is made with the introduction of a new concept, the "CO(2)-Water", to illustrate the impacts of releasing carbon from underground to atmosphere and of the water needed to sequestrate it over the life cycle of the assessed fuels. Using this method resulted that gasoline from fossil fuels would indirectly "require" on average as much water as ethanol from sugar cane per unit of fuel energy produced.     

Energy intensity of computer manufacturing: hybrid assessment combining process and economic input-output methods

The total energy and fossil fuels used in producing a desktop computer with 17-in. CRT monitor are estimated at 6400 megajoules (MJ) and 260 kg, respectively. This indicates that computer manufacturing is energy intensive: the ratio of fossil fuel use to product weight is 11, an order of magnitude larger than the factor of 1-2 for many other manufactured goods. This high energy intensity of manufacturing, combined with rapid turnover in computers, results in an annual life cycle energy burden that is surprisingly high: about 2600 MJ per year, 1.3 times that of a refrigerator. In contrast with many home appliances, life cycle energy use of a computer is dominated by production (81%) as opposed to operation (19%). Extension of usable lifespan (e.g. by reselling or upgrading) is thus a promising approach to mitigating energy impacts as well as other environmental burdens associated with manufacturing and disposal.     

Comparative analysis of the production costs and life-cycle GHG emissions of FT liquid fuels from coal and natural gas

Liquid transportation fuels derived from coal and natural gas could helpthe United States reduce its dependence on petroleum. The fuels could be produced domestically or imported from fossil fuel-rich countries. The goal of this paper is to determine the life-cycle GHG emissions of coal- and natural gas-based Fischer-Tropsch (FT) liquids, as well as to compare production costs. The results show that the use of coal- or natural gas-based FT liquids will likely lead to significant increases in greenhouse gas (GHG) emissions compared to petroleum-based fuels. In a best-case scenario, coal- or natural gas-based FT-liquids have emissions only comparable to petroleum-based fuels. In addition, the economic advantages of gas-to-liquid (GTL) fuels are not obvious: there is a narrow range of petroleum and natural gas prices at which GTL fuels would be competitive with petroleum-based fuels. CTLfuels are generally cheaper than petroleum-based fuels. However, recent reports suggest there is uncertainty about the availability of economically viable coal resources in the United States. If the U.S. has a goal of increasing its energy security, and at the same time significantly reducing its GHG emissions, neither CTL nor GTL consumption seem a reasonable path to follow.     

Environmental implications of municipal solid waste-derived ethanol

We model a municipal solid waste (MSW)-to-ethanol facility that employs dilute acid hydrolysis and gravity pressure vessel technology and estimate life cycle energy use and air emissions. We compare our results, assuming the ethanol is utilized as E85 (blended with 15% gasoline) in a light-duty vehicle, with extant life cycle assessments of gasoline, corn-ethanol, and energy crop-cellulosic-ethanol fueled vehicles. We also compare MSW-ethanol production, as a waste management alternative, with landfilling with gas recovery options. We find that the life cycle total energy use per vehicle mile traveled for MSW-ethanol is less than that of corn-ethanol and cellulosic-ethanol; and energy use from petroleum sources for MSW-ethanol is lower than for the other fuels. MSW-ethanol use in vehicles reduces net greenhouse gas (GHG) emissions by 65% compared to gasoline, and by 58% when compared to corn-ethanol. Relative GHG performance with respect to cellulosic ethanol depends on whether MSW classification is included or not. Converting MSW to ethanol will result in net fossil energy savings of 397-1830 MJ/MT MSW compared to net fossil energy consumption of 177-577 MJ/MT MSW for landfilling. However, landfilling with LFG recovery either for flaring or for electricity production results in greater reductions in GHG emissions compared to MSW-to-ethanol conversion.     

Acute View Transport biofuels: Can they help limiting climate change without an upward impact on food prices?

Comprehensive life cycle assessments show that current transport biofuels often do worse than conventional fossil transport fuels as to the emission of greenhouse gases. Biofuels from microalgae grown with present technology and lignocellulosic biofuels from current arable land or land that is to be deforested are unlikely to do better regarding the emission of greenhouse gases than fossil transport fuels. When crops characterized by relatively low fossil fuel inputs and relatively high biomass yields are grown on abandoned agricultural and marginal soils which currently sequester little carbon, cropping for transport biofuels may help in limiting climate change without an impact on food prices. For such cropping one probably has to go beyond the market mechanism. Worldwide, there is some scope for the use of harvest residues in biofuel production. However, European arable soils show on average large losses of soil carbon and this rather favors increased addition of such residues to soils. Received: November 17, 2008; accepted: December 3, 2008     

Compilation and application of Japanese inventories for energy consumption and air pollutant emissions using input-output tables

Preparing emission inventories is essential to the assessment and management of our environment. In this study, Japanese air pollutant emissions, energy consumption, and CO2 emissions categorized by approximately 400 sectors (as classified by Japanese input-output tables in 1995) were estimated, and the contributions of each sector to the total amounts were analyzed. The air pollutants examined were nitrogen oxides (NOx), sulfur oxides (SOx), and suspended particulate matter (SPM). Consumptions of about 20 fossil fuels and five other fuels were estimated according to sector. Air pollutant emission factors for stationary sources were calculated from the results of a survey on air pollution prevention in Japan. Pollutant emissions from mobile sources were estimated taking into consideration vehicle types, traveling speeds, and distances. This work also counted energy supply and emissions from seven nonfossil fuel sources, including nonthermal electric power, and CO2 emissions from limestone (for example, during cement production). The total energy consumption in 1995 was concluded to be 18.3 EJ, and the annual total emissions of CO2, NOx, SOx, and SPM were, respectively, 343 Mt-C, 3.51 Mt, 1.87 Mt, and 0.32 Mt. An input-output analysis of the emission inventories was used to calculate the amounts of energy consumption and emissions induced in each sector by the economic final demand.