基于LCA的废弃手机资源化有效运输范围量化研究

基于生命周期评价方法（LCA）分析了废弃手机资源化过程的环境效益和跨区域运输过程的环境影响,并在此基础上提出了废弃手机跨区域流动的有效运输范围及其量化方法.通过采用IMPACT 2002+评价模型,从人体健康、生态系统质量、气候变化、资源消耗四方面对当前中国废弃手机两种典型资源化利用方案和运输过程的环境表现进行了评估.结果表明,两种资源化方案均表现出显著环境效益;部件再使用和材料再生过程是废弃手机资源化环境效益的主要贡献来源;综合考虑跨区域运输过程,在满足环境效益为正的前提下,包括部件再使用和不包括部件再使用两种资源化方案的有效运输范围分别为0~3094km与0~1248km.同时,对跨区域运输过程关键参数分析后发现,提高铁路运输占比和降低货车运输空返率可以有效扩大废弃手机跨区域转移的运输范围.     

Population dynamics,rural livelihoods and forest protection projects in Sub-Saharan Africa: experiences from Santa,Cameroon

The study examines mainstream efforts to rehabilitate and conserve forests in Cameroon, and concludes that technocratic blueprints will always flounder when they come face-to-face with the real world of complex human relations in poverty-stricken societies. These result from the failure to integrate concerns relating to rights, needs and priorities of rural communities, who are the local natural resource users. The paper argues that when rural livelihoods are affected negatively, the adjacent forest communities often respond in ways involving conflict, illegal exploitation of resources and apathy, which makes the realisation of conservation goals very remote. There is, therefore, need for a broader perspective that links environmental protection with human welfare. Consequently, the study advocates that Social Impact Assessment (SIA) be an integral part of such conservation projects if success is to be achieved.     

Evaluating environmental and economic benefits of yellow dust storm-related policies in north China

Yellow-dust storms (YDSs) have attracted increasing attention worldwide in the past decade. They can extensively disrupt socioeconomic activities and pose hazards to ecosystems, as well as to human health. In recent years, China has invested multi-billions of dollars to mitigate the impact of YDSs. However, the effectiveness of such YDS control programmes has rarely been evaluated. This research develops a causal model to quantify the environmental benefits of YDS control programmes in China, and further employs regional economic models to evaluate the ensuing economic impacts. The economic benefits generated from the YDS control programmes should remain stable across the years, primarily because of the multiplier effect of the investments, while the environmental benefits tend to decline over time. Our results suggest that YDS control programmes should consider stimulating local economic activities in addition to environmental goals in order to be cost-effective and sustainable in the long term.     

生命周期评价在我国乙烯行业环境评估中的应用

采用IMPACT 2002+方法对我国的乙烯行业进行了生命周期评价(LCA)研究,分析了包括原油生产、原煤生产、原料生产、乙烯生产和电力生产5个环节在内的13种污染物排放对乙烯行业的环境影响.结果表明,乙烯工业对不可再生能源原油的消耗,对温室效应、呼吸效应和水体酸化等的环境影响潜值最为严重.减少乙烯生产环节和原料生产环节(炼油过程)的SO2、NOx、CO2等气体的排放,以及原油开采过程的CH4逸放,是改善环境影响的关键因素.同时,以石脑油为原料裂解乙烯工艺比以轻烃为原料制乙烯工艺对环境的影响要小.而煤制烯烃工艺对环境影响较大,仍具有一定改进空间.总体来看,经过近十年发展,我国乙烯行业对资源利用效率和缓解尾气排放两方面都有显著的提升.