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181.
The proximity principle—disposing of waste close to its origin—has been a central value in municipal solid waste (MSW) management in Japan for the last 30 years and its widespread adoption has helped resolve numerous “Not in My Backyard” issues related to MSW management. However, MSW management costs have soared, in large part because of aggressive recycling efforts and because most MSW is incinerated in a country that has scarce landfill capacity. In addition, smaller, less sophisticated incinerators have been closed because of high dioxin emissions. Rising costs combined with the closure of smaller incinerators have shifted MSW management policy toward regionalization, which is the sharing of waste management facilities across municipalities. Despite the increased use of regionalized MSW facilities, the proximity principle remains the central value in Japanese MSW management. Municipal solid waste management has become increasingly regionalized in the United States, too, but different driving forces are at work in these two countries. The transition to regionalized MSW management in Japan results from strong governmental control at all levels, with the central government providing funds and policy direction and prefectures and municipalities being the primary implementing authorities. By contrast, market forces are a much stronger force with US MSW management, where local governments—with state government oversight—have primary responsibility for MSW management. We describe recent changes in Japan’s MSW programs. We examine the connections between MSW facility regionalization, on the one hand, and, on the other hand, the proximity principle, coordination among local governments, central government control, and financing mechanisms.  相似文献   
182.
目的 研究对火工品适用的温湿度加速模型,以及加速系数计算程序,获取准确的温湿度加速系数外推公式.方法 通过分析国内外使用的各种双因素加速模型的适用性,确定火工品适用的温湿度加速模型,采用免费自由的开源统计分析软件——R软件,对通过加速试验获取的某点火头2种温湿度加速条件下的试验数据,进行单组数据拟合和多组数据拟合两种温湿度加速老化算法的开发,并且对2种算法、3种寿命分布下寿命外推的准确性进行对比分析.结果 确定了Peck模型适合用于火工品的温湿度加速模型,获取了某电点火头对应的温湿度加速系数和湿度项反应速率常数.结论 基于多组数据拟合的温湿度加速老化算法,比基于单组数据拟合的温湿度加速老化算法对试验数据的兼容性好.3种寿命分布中,Weibull分布的加速系数计算结果最保守.  相似文献   
183.
Extended producer responsibility is advocated for its capacity to spur resource efficiency through green innovation and closing loops downstream of consumption. Its rationale is the extension of the polluter-pays principle to the post-consumption phase. This paper analyze the underlying mechanisms that are supposed to work under the EPR approach, and proposes an alternative view. The main purpose of EPR is seen as the creation of the bases for legitimizing the involvement if industry taking over the task of diverting waste from landfill. Its success rests on the superior managerial capacity of industry and the need to organize post-consumption markets that transcend the local scale and have access to the economies of scale and scope. The emphasis on producers does not add anything special, but may reinforce the bases for legitimizing the implicit delegation of power to industry. Primary and above all, we have witnessed in the last 20 years a gigantic effort of market design, and this is the main demonstration of EPR's success.  相似文献   
184.
Extended producer responsibility (EPR) has become a dominant policy paradigm for the management of waste electrical and electronic equipment (WEEE) in the last two decades. In South Korea the principle has guided the evolution of the resource circulation policy even before its official introduction through a revision of the recycling law in 2002. Elements of producer responsibilities could be found in the producer-based deposit refund system (DRS) a decade earlier and they were strengthened through the enactment of a new resource circulation law in 2008. This article reviews the policy changes in South Korea for the management of WEEE during the past 20 years. The focus of the analysis is on the impacts of EPR and the producers’ responses that were expressed through the quantity and the quality of material flows in the society. The findings are discussed in light of international experiences in order to outline measures to improve the effectiveness of the EPR-based resource circulation policy that could have broader implications beyond the case study.  相似文献   
185.
EU's long-term objective is to become a recycling and resource effective society, where waste is utilized as a resource and waste generation is prevented. A system dynamics model was developed to analyze the policy mechanisms that promote packaging material efficiency in products through increased recycling rates. The model includes economic incentives such as packaging and landfill taxes combined with market mechanisms, behavioral aspects and ecological considerations in terms of material efficiency (the packaging material per product unit, recycled fraction in products). The paper presents the results of application of various policy instruments for increasing packaging material efficiency and recovery rate and reducing landfilled fraction. The results show that a packaging tax is an effective policy instrument for increasing the material efficiency. It ensures the decrease of the total consumption of materials and subsequent waste generation. The tax helps to counteract a rebound effect, which, as identified by the analysis, can be caused by reduced material costs due to eco-design. The model is applied to the case of Latvia. Yet, the elements and structure of the model developed are similar to waste management systems in many countries. By changing numeric values of certain parameters, the model can be applied to analyze policy mechanisms in other countries.  相似文献   
186.
进口利用废旧资源在解决我国原生资源不足、节约能源、降低环境负荷、满足日益增长的物资需要具有重要的意义,但进口废旧资源会因夹带、处置加工等环节带来环境污染.文章梳理了我国允许废旧资源进口利用的背景需求,探讨了科学识别进口废旧资源、加工利用相关行业产生的环境问题,提出了进一步加强环境监管的对策方案,以推进废旧资源进口和加工贸易的健康发展.  相似文献   
187.
In this paper, the implementation of effective waste management practices in construction projects and sites is analyzed, using data from a survey answered by 74 Spanish construction companies based in Catalonia. Most commonly implemented practices were found to be on-site cleanliness and order, correct storage of raw materials, and prioritization of the nearest authorized waste managers. The least widespread practices were the use of a mobile crusher on site, the creation of individualized drawings for each construction site, and the dissemination of the contents of the waste management plan to all workers, to help them to meet its requirements. Waste regulations for construction and demolition, and the corresponding construction waste management facilities, were designed before the recession in the Spanish construction sector. Current waste generation rates are still below predicted levels, and the infrastructure was designed for five times more waste generation. Even so, the percentage of reused and recycled waste currently amounts to 43%. Survey respondents highlighted various instruments and measures that would make the management of construction and demolition waste more sustainable. Most of the opportunities identified by construction firms are within the scope of government and related to a combined system of bonus and penalties and the establishment of environmental awareness and training programmes for all the stakeholders. Within the scope of authorized waste managers, firms suggested improvements such as the standardization of fees, a reduction of the time until the issue of waste management certificates, a higher number of inspections, and a change in the current model of a few large construction waste management facilities. This research is useful to better understand the current status of construction and demolition waste management in construction projects and sites. Thus, the results of this research will guide policy makers and relevant stakeholders such as contractors, clients, architects and engineers to achieve the EU target of recovering 70% of construction and demolition waste in 2020. In this sense, reliable information can help governments and professional associations to set future C&D waste management regulations, training programmes and dissemination tools, inspections, etc.  相似文献   
188.
Incineration is the main option for residual Municipal Solid Waste treatment in France. This study compares the environmental performances of 110 French incinerators (i.e. 85% of the total number of plants currently in activity in France) in a Life Cycle Assessment perspective, considering 5 non-toxic impact categories: climate change, photochemical oxidant formation, particulate matter formation, terrestrial acidification and marine eutrophication. Mean, median and lower/upper impact potentials are determined considering the incineration of 1 tonne of French residual Municipal Solid Waste. The results highlight the relatively large variability of the impact potentials as a function of the plant technical performances. In particular, the climate change impact potential of the incineration of 1 tonne of waste ranges from a benefit of ?58 kg CO2-eq to a relatively large burden of 408 kg CO2-eq, with 294 kg CO2-eq as the average impact. Two main plant-specific parameters drive the impact potentials regarding the 5 non-toxic impact categories under study: the energy recovery and delivery rate and the NOx process-specific emissions. The variability of the impact potentials as a function of incinerator characteristics therefore calls for the use of site-specific data when required by the LCA goal and scope definition phase, in particular when the study focuses on a specific incinerator or on a local waste management plan, and when these data are available.  相似文献   
189.
In partnership with the US Department of Energy’s Office of Industrial Technology, Whyco Technologies, Inc., has developed an innovative perforated plating barrel used in the plating of metal parts. This new technology employs a thin-walled construction, differing from the traditional thick-wall design required to provide adequate structural integrity. The thicker walls lowered the efficiency of transferring plating solution into and out of the barrel and diminished the electrical current pushed through the holes and onto the parts being plated. By machining pockets out of the traditional thick-walled perforated structure, Whyco produced a ‘honeycomb’ of staggered cells, allowing for the greatest number of holes per open area while maintaining structural integrity. Hydrodynamic pumping occurs during barrel rotation to create greater solution transfer than in traditional barrels. The Whyco barrel has higher current density plating, which leads to faster plating cycles, reduced bath concentration, and better plating of difficult chemistries such as in alloys. This new technology has helped the company reduce energy use by 16%, eliminate more than 480 tons/year of solid waste, and reduce wastewater by more than 17 000 gallons/day. The resulting cost savings total more than $500 000 annually. The company has manufactured and sold more than 275 of these barrels to other electroplating companies that are reporting up to a 40% increase in plating productivity and similar energy and environmental impacts.  相似文献   
190.
提出了一种适用于单件或小批量生产大中型风机叶轮前盘的新工艺——滚轮芯模简易旋压成形工艺,这种工艺经济实用,简便易行,可在一定范围内推广应用。  相似文献   
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