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591.
This paper briefly describes waste treatment trends in Sweden and describes an example of state-of-the-art treatment in a local integrated waste treatment system (Bor?s). The focus is on treatment of household waste, to illustrate what can be done to establish a sustainable waste treatment system with high recovery of materials and energy. The various processes have resulted in a low amount of landfilled household waste, and high proportions of recovered energy and materials. Heat, electricity, vehicle fuel and fertilizers, metals and construction materials are recovered from the local waste in Bor?s, with less than 4% of domestic waste being sent to landfill.  相似文献   
592.
基于SEM的建筑施工企业KPI安全绩效评价   总被引:3,自引:2,他引:1  
鉴于建筑施工企业生产安全和服务质量管理以及企业员工综合素质和工作效率的重要性,探讨影响建筑施工企业安全生产的因素,并对建筑施工企业的安全绩效进行全面、客观的评价。采用关键绩效指标(KPI)建立基于人的因素、管理制度、施工设备和环境条件四维度的建筑施工企业安全绩效评价指标体系,研究将结构方程模型理论引入到评价体系中,构建安全绩效评价的结构方程模型(SEM)。总结评价的一般程序,并结合实例,从定量的角度对某建筑施工企业安全绩效进行评价。结果表明,KPI评价体系和SEM评价模型评估得出建筑企业安全绩效影响因素的程度是:人的因素>管理制度>环境条件>施工设备。  相似文献   
593.
Understanding technological change provides a crucial basis for governing sustainability transitions. In this paper we present an analysis of technological change using the example of Swiss thermal waste processing. In recent years, increased concerns about the low quality of residues from grate-firing systems led to the examination of alternative technologies. Yet despite clear indications of a potential better performance with respect to residue quality, none of these alternatives has been adopted. Based on a two-stage knowledge integration among 15 leading experts, in a retrospective analysis we identified factors that have significantly affected technological change in Swiss thermal waste processing. These factors were then related to three technological options representing different types of technological change, i.e., from incremental improvements of the existing to the implementation of a new technology. The results indicate that technological change is currently in a technological lock-in and provide detailed insights on the causes. The lock-in results in the step-wise further development of the status quo grate-firing system despite its limitations for improving the residue qualities. Almost all factors (legal, economic, societal, technological) of the existing ‘thermal waste management’ system have been well adapted to the cost- and energy-efficient grate-firing technology, blocking innovative technologies from entering the Swiss market. In addition, pressures from the context, e.g., societal pressure related to landfill risks, have not been strong enough to promote non-incremental change.  相似文献   
594.
595.
建设长江产业带不能沿用旧的发展模式,必须寻求一条人口、经济、社会、环境与资源相互协调的、能满足当代人的需求而又不对满足后代人需求的能力构成危害的可持续发展道路。  相似文献   
596.
Entrances to many caves occupied by the endangered Indiana bat ( Myotis sodalis ) have been modified to control human access. We show that modifying cave entrances can degrade the bats' winter habitat, we demonstrate one mechanism by which this damage occurs, and we document a restoration experiment. We compared a large bar population in an unmodified cave with a small, reduced bat population in a cave with warm winter temperatures resulting from an entrance wall that impeded air exchange. In the modified cave, mean winter temperature at the hibernation site was 5.0° C higher than in the unmodified cave, bats entered hibernation at a 5% higher body mass, bats lost 42% more mass and the frequency distribution of late-winter mass was truncated, with no bats weighing less than 5.4 g. The results describe unacceptable extremes for hibernation: subfreezing temperatures and warm temperatures causing mass-loss rates of more than 0.009 g/day. Over a decade following removal of the entrance-constricting wall, the population increased from 2,000 to 13,000 bats. Previous recommendations, based on common-sense observation, to open blocked cave entrances are confirmed by this study. The similar case of Coach Cave, Kentucky, offers the potential for recovery of 100,000 Indiana bats.  相似文献   
597.
598.
介绍了氮气泡沫研究进展和现状,分析了氮气泡沫的灭火原理、稳定性以及应用实例。氮气是惰性气体,不溶于水,在水中扩散速率较小,其与泡沫液混合发泡产生的氮气泡沫与空气、二氧化碳等相比,具有持久惰化、稳定性好,灭火效果显著等优势。  相似文献   
599.
天气形势是驱动大气污染物变化的最初动力,其与大气污染有着密切联系.探究天气形势对各季节空气质量的影响,可为污染防控提供一定的指导意见.本文利用NCEP-FNL再分析资料、环境监测数据,研究了天气形势对2014?—?2018年关中地区各季节空气质量的影响.结果表明:春、秋、冬季"槽西南型"和"高压东南型"对大气污染物浓度...  相似文献   
600.
Landfills generate emissions over long periods, often longer than a lifetime. The longest lasting emission is leachate. In order to estimate the future requirements for leachate treatment, different kinds of leaching tests may be applied. In this paper, shaking leaching tests (SLT), landfill-simulator leaching tests and a field-cell leaching test performed with ash, municipal solid waste (MSW) and MSW+ash are evaluated. The tests are compared and the factors influencing leaching are identified and discussed. The factors are: liquid to solid (L/S) ratio, water withdrawal, recirculation rate, presence or absence of biological processes, size of particles, duration of experiment, temperature and pre-treatment of the waste. The presence of biological processes has the greatest impact on leaching and is the main reason why SLT is less useful for long-term predictions. The landfill simulator tests were found to be useful for several different kinds of predictions. However, they are not reliable for predicting the L/S required for reaching a certain concentration. The possibilities for reliable long-term predictions would be facilitated by a better knowledge of the influence of various factors on leaching. Such an increased knowledge would make it possible to enhance waste stabilisation in leaching tests as well as in full-scale landfills.  相似文献   
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