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501.
This research has been motivated by a real-life problem of a waste cooking oil collection system characterized by the existence of multiple depots with an outsourced vehicle fleet, where the collection routes have to be plan. The routing problem addressed allows open routes between depots, i.e., all routes start at one depot but can end at the same or at a different one, depending on what minimizes the objective function considered. Such problem is referred as a Multi-Depot Vehicle Routing Problem with Mixed Closed and Open Inter-Depot Routes and is, in this paper, modeled through a mixed integer linear programming (MILP) formulation where capacity and duration constraints are taken into account. The model developed is applied to the real case study providing, as final results, the vehicle routes planning where a decrease of 13% on mileage and 11% on fleet hiring cost are achieved, when comparing with the current company solution.  相似文献   
502.
In this essay, the authors examine the public discourse of three different proponent groups (Native Americans, Industry, and Community Advocates) to gain insight into the narratives used to justify the decision to support a typically unwanted land use. The questions they ask are: first, who are the actors, what is their agency, and what is their purpose, as revealed through an analysis of the compiled text? Second, in what ways do their stories combine into a coherent narrative of support for the project; and, finally, does the meta-narrative resonate with their primarily western states audience? They conclude with suggestions as to how this project informs participants in other waste management controversies.  相似文献   
503.
Moving up the waste hierarchy is a key priority for UK waste policy. Waste prevention requires policy interventions to promote reuse. The term ‘reuse exchange’ has been adopted by UK policy makers to describe a variety of second-hand trading outlets including car boot sales, charity shops and online exchange sites. As waste policy is based on tonnage diverted from disposal (or landfill), policy interventions to promote reuse exchange will be based on the weight of goods estimated to be flowing through these sites. This paper uses a combination of field survey data and scale-up estimation to quantify and characterise the weight of goods exchanged at car boot sales in England in 2012. This is estimated at 50–60 000 tonnes per annum. The paper emphasises that movement up the waste hierarchy brings waste policy into closer contact with household consumption practices. It draws on qualitative research to show that, for participants, car boot sales are not associated with waste prevention. Instead, car boot sales rely on stocks of surplus household goods and exemplify the culture of thrift, which enables more, not less, consumption. The paper shows the collision between the social values that inform thrift and the environmental values that underpin reuse; and it argues that the policy goal of enhanced recovery for reuse might best be achieved by working with consumer culture. Two ways of achieving this are suggested: interventions that make it easier for consumers to do the right thing, through promoting opportunities for the circulation of stocks of surplus goods, for example, through increasing the frequency of car boot sales; and interventions which recognise that car boot sales also generate waste, which could be recovered for reuse.  相似文献   
504.
以含锌废盐酸为原料制备磷酸锌[Zn3(PO4)2],探讨含锌废盐酸中Zn、Fe、Cr、Ni等重金属质量分数、TOC质量浓度、磷酸体积分数和反应时间等典型因素对Zn3(PO4)2纯度及化学组成结构的影响,并用XRD及SEM表征Zn3(PO4)2的物相结构。结果表明,含锌废盐酸可制备纯度较高、结构较为稳定的Zn3(PO4)2产品,制备过程中废盐酸中的Fe对Zn3(PO4)2产出纯度的影响较大;Zn3(PO4)2的产出纯度随TOC质量浓度的升高而下降;当磷酸体积分数低于85%时,对Zn3(PO4)2产出纯度总体呈正相关趋势,而高于85%后,产出纯度则有所降低;反应时间为5 h时制备Zn3(PO4)2的效率最高。  相似文献   
505.
危险废物焚烧处置与管理   总被引:1,自引:1,他引:1  
秦易 《环境保护科学》1998,24(3):19-21,39
结合美国的危险废物焚烧处置与管理实际,介绍了危险废物焚烧处置的主要技术环节及对环境的影响,在展望焚烧处置技术发展前景的同时,希望其在我国的危险废物的处置工作中发挥作用.  相似文献   
506.
萃取—汽提法处理硝基苯废水的研究   总被引:11,自引:1,他引:11  
先用苯萃取使废水中硝莽本的浓度达3ppm以下,再用水蒸气汽提使废水中的苯浓度达10ppm以下,并使硝基苯浓度进一步降低,处理后的废水全面达到国家二级排放标准。苯和萃取出的硝基苯都可回收利用.。  相似文献   
507.
利用煤矸石熔制岩棉的机理与工艺研究   总被引:3,自引:0,他引:3  
合理利用废弃物资源,防止环境污染是世界各国急待解决的问题.本文介绍了国内第一条煤矸石岩棉生产线的工艺设计及其年产万吨的生产性试验,表明该产品的主要技术性能已达到国家规定的优等品标准;并探讨了煤矸石熔制岩棉的机理,为煤矸石资源的高效益深度开发利用提供了新的途径.  相似文献   
508.
采用顶空-气相色谱法测定固定污染源废气中甲胺、二甲胺、乙胺、二乙胺和三乙胺,通过优化相关测定条件,使5种挥发性脂肪胺在0.005 mg/L~25.0 mg/L范围内线性良好,方法检出限为0.004 mg/m3~0.4 mg/m3(以采集20 L空气样品计).5种挥发性脂肪胺的加标回收率为91.0%~113%,6次测定结...  相似文献   
509.
Trends in waste plastics and recycling   总被引:2,自引:0,他引:2  
Zero emission is an ambitious project aimed at the conversion of the conventional top-down or one-directional flow type production systems of modern society to those of a recycling type. The basic idea underlying this project is to understand in detail the material flow mechanism in a particular segment of society and to evaluate the transformability of the hitherto one-directional types of process into recycling types. The authors, members of the Zero-Emission Research Group of Japan, are investigating the material flow of plastics in Japan. The present work describes the features of this project, as well as the results obtained so far. Received: May 28, 1998 / Accepted: October 16, 1998  相似文献   
510.
用硫化钠从废定影液中以硫化银的形式回收银,高温灼烧硫化银得纯银,再制备成硝酸银。硝酸银纯度达99.5%,银回收率为93%。  相似文献   
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