An LCA based indicator for evaluation of alternative energy routes

Politicians and policymakers are searching for alternatives for current energy conversion systems in order to reduce environmental pollution whilst preserving scarce natural resources. When defining new alternatives it is important to find out how environmentally friendly and sustainable these alternatives are, and which of them will ensure a major improvement in environmental issue. To answer such questions the present work proposes a new type of indicator based on exergy life cycle data. Alternative energy routes towards different services and commodities are compared in terms of environmental impact and indirect natural resource costs. Two case studies are presented using data from the Ecoinvent database (v2.01 2007) to compare alternatives to petrol transport and fuel oil power generation. The alternative transport routes assessed were methanol and biogas fueled cars, and wind electricity in the case of power generation.     

Life-cycle inventory analysis of concrete production: A critical review

Concrete is one of the most widely used building materials with a global consumption rate approaching 25 gigatonnes per year. Consequentially, its environmental burden is significant in terms of resource use and environmental emissions. There is a diverse audience of decision makers and manufacturers who are interested in understanding and lowering the environmental impact of concrete and other buildings materials, which requires a life-cycle assessment (LCA) approach. A critical first step in any LCA is the compilation of a credible life-cycle inventory (LCI), upon which subsequent life-cycle impact assessment (LCIA) can be based. This article reviews the strengths and weaknesses of concrete LCIs to date, and offers a research roadmap to improve the quality of future cement and concrete LCIs and meet the needs of major LCA users.     

光学相干层析成象技术基本原理

本文介绍了光学相干层析成象技术（ＯＣＴ），阐述了层析成象的基本原理，讨论了层析象的信息内容。     

Ethanologens vs. acetogens: Environmental impacts of two ethanol fermentation pathways

Bioconversion production of ethanol from cellulosic feedstock is generally proposed to use direct fermentation of sugars to ethanol. Another potential route for ethanol production is fermentation of sugars to acetic acid followed by hydrogenation to convert the acetic acid into ethanol. The advantage of the acetogen pathway is an increased ethanol yield; however, using an acetogen requires the additional hydrogenation, which could substantially affect the life cycle global warming potential of the process. Assuming a poplar feedstock, a cradle to grave Life cycle assessment (LCA) is used to evaluate the environmental impacts of an acetogen based fermentation pathway. An LCA of a fermentation pathway that uses ethanologen fermentation is developed for comparison. It is found that the ethanologen and acetogen pathways have Global Warming Potentials (GWP) that are 92% and 46% lower than the GWP of gasoline, respectively. When the absolute GWP reduction compared to gasoline is calculated using a unit of land basis, the benefit of the higher ethanol yield using the acetogen is observed as the two pathways achieve similar GWP savings. The higher ethanol yield in the acetogen process plays a crucial role in choosing a lignocellulosic ethanol production method if land is a limited resource.     

光学相干层析成像技术的应用

介绍了光学相干层析成像技术在不同领域的应用,预言了未来的发展趋势。     

某合成革企业湿法生产线的生命周期评价清单分析

将生命周期方法应用于合成革湿法生产工艺,收集和量化了各工序能量和物质的输入输出,得到了合成革生命周期清单(LCI)。每投入1m2无纺布,需要输入水117.90kg,化工原料1.7kg,电0.475kWh,煤312g;得到贝斯1.04m2,产生废水112.19kg,CODCr26.3g,氨氮4.7g,DMF989g,PVA2.8g,总磷0.3g。在此基础上提出了合成革清洁生产的建议。