Aluminum recovery from electronic scrap by High-Force® eddy-current separators

The amount of electronic scrap which contains a substantial portion of non-ferrous metals, primarily copper and aluminum, has been growing. The present study is directed toward aluminum recovery by a newly developed eddy current separator. The investigation on shredded personal computer and printed circuit board scrap demonstrates that the High-Force® eddy-current separator will be applicable for this purpose. It has been shown that, by a single pass of the materials on the High-Force® eddy-current separator, an aluminum concentrate out of personal computer scrap can be obtained with a purity of 85%, while maintaining a recovery in excess of 90%, with the feed rate being up to 0.3 kg/min.     

横向流除油器的研制及其在油田含油污水处理中的应用

研制开发出的新型横向流除油器具有独特性能,除油器的聚结区由相互正交的梯形板组所组成,水流在其中沿正弦波路流动;分离区由一系列单元六面体所组成的三维板构成,水流在其中沿水平方向流动,并且流速不断变化。水流在设备内沿水平方向流动,油垂直向上移动,泥垂直向下滑动,处理后水质不会产生二次污染等问题。用该设备处理大庆油田含油污水效果良好,完全可以代替现有工艺中的自然沉降罐和混凝沉降罐。     

Optimization of the recovery of plastics for recycling by density media separation cyclones

Material recovery processes are presented as the optimum option for recycling plastic wastes as a means of recovering hydrocarbon resources. There exist a large variety of automated material recovery processes for recycling of such wastes but each with significant limitations. Of these, the separation based on differences in densities is advocated as the optimum process either for producing recycled products or preparing wastes for subsequent recovery processing.Density separation processes based on cyclone type density media separation (DMS) is presented as an important, potential method for increasing plastics recycling process capacities. It is demonstrated to have the capacity to separate a significantly larger range of particle sizes than those presently processed industrially. The mathematical relationship for the prediction of quality of typical LARCODEMS type density media separations by particle size and density as expressed by the Ecart Probable is presented.A proposed device configuration is presented for density media separation to optimize the recovery and purity of both density fractions produced. It is also suggested that to be economically viable, a large scale of operation is required for industrial plastics recycling operations recovering and producing a number of different plastics with a purity to be used as a substitute for virgin material.     

挥发性有机物(VOCS)活性炭吸附回收技术综述

随着我国经济建设的发展，各类有机溶剂的应用越来越广，有机废气的排放量也随之逐年增加，其所带来的空气污染等环境问题已经引起全世界的关注。过去，研究人员主要致力于开发高效的VOCs控制技术。随着我国建立可持续社会目标的提出，越来越多的人开始关注经济有效的VOCs回收方法。本文重点介绍了活性炭吸附回收VOCs的工艺现状和研究进展，并预测了VOCs分离回收技术的发展趋势。     

稠油罐底泥碳化处理技术研究与应用*

为解决油田生产过程中产生的稠油罐底泥的环境污染和资源浪费问题,在分析含油污泥性质和特点的基础上开发了稠油罐底泥碳化处理工艺及配套装置。介绍了该技术的原理及工艺流程,在小试、中试研究的基础上,进行了工业化应用,稠油罐底泥的处理效果表明:油气回收率可达90%以上,轻质油品占回收油总量的78%以上,焚烧处理后的残渣未检出矿物油;烟气和废水相关项目的监测值符合相关标准。     

有色金属工业固废资源属性多维度评价体系构建——以锡尾矿为例

提升固废综合利用水平是近年各类政策、法规、标准的要求,从固废资源属性入手,全面分析和评价固废资源属性特征,有利于固废综合利用技术的开发应用,是提升固废综合利用水平的有效途径。本文针对目前固废资源属性特征评价体系缺失、资源属性数据缺乏等问题,以有色金属工业固废为例建立了一套资源属性评价体系。从有色金属工业固废自身的物质和能量属性,以及使其成为固废的环境、经济、技术、社会等6个维度构建评价指标体系,形成定性和定量相结合的14项指标,并以锡尾矿为例,进行实证。结果表明,除能量维度外,对锡尾矿开展资源化利用的综合潜力较大,其最具潜力的利用途径是回收有价金属,其次是作为陶瓷制品的原料,评价也指出未来在锡尾矿作为建材利用的技术方面仍需要加强研发和应用推广。评价结果以定量为主结合定性描述,为锡尾矿资源化利用方向提供了具体参照和指导,也为探索固废资源属性全面评价、完善固废资源属性数据库提供理论和方法学的借鉴。     

我国蔬菜和蔬菜种植土壤的重金属污染现状与一般规律

本文对我国部分城市农用土壤和蔬菜重金属污染现状进行了综述,重金属污染在蔬菜种植土壤和蔬菜中主要是以Pb、Cd、Hg为主,且工业城市和人口密度大的城市尤为突出。分析了植物吸附重金属的一般规律与影响因素。为防治重金属污染提供了理论依据。     

“第一类污染物”防治需求的紧迫性及其对策措施

"第一类污染物"是指会对人体健康产生长远不良影响的污染物,包括8种重金属和类金属。已经证实,工业源重金属超量排放严重,使水土及生态环境遭受到"第一类污染物"的严重污染,面临的"第一类污染物"防治形势更加紧迫。本文在重金属污染现状与治理需求分析的基础上,通过长期调研,针对重点行业提出了6项综合防治措施,建议从源头严格控制排放总量,对重点企业进行监管与治理,总结与创新重金属修复新技术等,旨在推动第一类污染物的污染防治。     

Electronic waste recycling: A review of U.S. infrastructure and technology options

The useful life of consumer electronic devices is relatively short, and decreasing as a result of rapid changes in equipment features and capabilities. This creates a large waste stream of obsolete electronic equipment, electronic waste (e-waste).Even though there are conventional disposal methods for e-waste, these methods have disadvantages from both the economic and environmental viewpoints. As a result, new e-waste management options need to be considered, for example, recycling. But electronic recycling has a short history, so there is not yet a solid infrastructure in place.In this paper, the first half describes trends in the amount of e-waste, existing recycling programs, and collection methods. The second half describes various methods available to recover materials from e-waste. In particular, various recycling technologies for the glass, plastics, and metals found in e-waste are discussed. For glass, glass-to-glass recycling and glass-to-lead recycling technologies are presented. For plastics, chemical (feedstock) recycling, mechanical recycling, and thermal recycling methods are analyzed. Recovery processes for copper, lead, and precious metals such as silver, gold, platinum, and palladium are reviewed. These processes are described and compared on the basis of available technologies, resources, and material input–output systems.     

生产者责任延伸制与电子废弃物管理——环境法规

日益增加的固体废弃物和工业废弃物已成为主要的社会问题。回收服务相对来说还很不足,导致很多废弃物只能进行简单的填埋、焚烧处理。这将导致严重的环境污染。借鉴国外一些发达国家废物管理领域的政策趋势,我国近年来出台了一系列关于电子废弃物管理的政策法规,但也暴露出正规的废物处理企业无法取得规模收益,入不敷出,电子废弃物处理基金的征收及补贴对象不明确等诸多问题。引入生产者责任延伸制将外部影响内部化,在理念和功能等方面适应了电子废弃物管理的需要。     

电脱盐含油废水除油工艺应用研究

原油电脱盐含油废水由于乳化带油严重,破乳分离困难,处理难度大。文章对目前工业化应用技术成熟的旋流油水分离、化学破乳及电化学3种电脱盐含油废水除油工艺,在工艺流程、工业应用现状、应用效果等几方面进行了对比研究。结果表明,电化学除油工艺具有除油率高、效果稳定、费用低、设备简单、抗冲击力强、占地面积小等优势,除油率和COD去除率大于90%,对悬浮物、胶体、重金属等也有一定的去除效果,具有较好的应用前景。     

废油基钻井液处理及油回收技术研究

目前现场处理废油基钻井液一般采用集中填埋或回注地层方法,这不仅难以解决其污染问题,同时也浪费了其中所含有的大量柴油资源。通过大量的实验室和现场试验研究,使用“化学热洗-析油-离心”处理工艺,油回收率达到84%以上;研制开发出的清油剂-凝聚剂-絮凝剂化学热洗配方体系,适用于多种废油基钻井液的回收油处理,具有较好的工业推广应用前景。     

Sound management of brominated flame retarded (BFR) plastics from electronic wastes: State of the art and options in Nigeria

Management of flame retarded plastics from waste electrical and electronic equipment (WEEE) has been posing a major challenge to waste management experts because of the potential environmental contamination issues especially the formation of polybrominated-dioxins and -furans (PBDD/F) during processing. In Nigeria, large quantities of electronic waste (e-waste) are currently being managed—a significant quantity of which is imported illegally as secondhand electronics. As much as 75% of these illegal imports are never reused but are rather discarded. These waste electronic devices are mostly older equipment that contains brominated flame retardants (BFRs) such as penta-brominated diphenyl ethers (PBDEs), and polybrominated biphenyls (PBBs) which are presently banned in Europe under the EU WEEE and RoHS Directives. Risk assessment studies found both to be persistent, bio-accumulative and toxic. The present management practices for waste plastics from WEEE in Nigeria, such as open burning and disposal at open dumps, creates potential for serious environmental pollution. This paper reviews the options in the environmentally sound management of waste plastics from electronic wastes. Options available include mechanical recycling, reprocessing into chemicals (chemical feedstock recycling) and energy recovery. The Creasolv^® and Centrevap^® processes, which are the outcome of the extensive research at achieving sound management of waste plastics from WEEE in Europe, are also reviewed. These are solvent-based methods of removing BFRs and they presently offer the best commercial and environmental option in the sound management of waste BFR-containing plastics. Because these developments have not been commercialized, WEEE and WEEE plastics are still being exported to developing countries. The industrial application of these processes and the development of eco-friendlier alternative flame retardants will help assure sound management of WEEE plastics.     

土壤污染的生物修复技术及其研究进展

近年来土壤污染呈现加重的趋势,有关污染土壤的修复研究正日益受到重视.生物修复技术是一项用于污染土壤治理的新技术.介绍了污染土壤生物修复技术,综述了近年来国内外土壤生物修复技术的研究和应用现状,并评述了土壤生物修复技术存在的问题以及污染土壤生物修复的发展方向.     

金昌市环境中铜的来源调查分析

大多数重金属通常是以气溶胶形式,如以烟、雾、尘分散在大气中.悬浮颗粒物中重金属是重要的大气污染物之一,目前已证实颗粒物中重金属如Ni、Cu、Cd、As等不但对人体具有毒害,而且具有致癌作用.金昌市是以硫化型金属矿为原料生产镍、铜的工业城市.因总体产业格局基本为原材料初级加工,能耗物耗高,原工艺水平低,环保欠帐较多,工业污染源超标排放污染物普遍,区域性环境污染相对突出.根据金昌市大气污染现状,通过对环境空气、土壤、植物中的重金属铜进行布点采样及分析,找出了重金属铜的污染分布特征以及来源.     

老化原油回收利用工艺技术现状及展望

老化原油的及时回收与高效处理,对于节约能源、减轻污水处理和集输系统的压力等问题,具有重要的经济和环境效益。文章对回收处理老化原油的常规技术和近几年出现的新技术进行分析,并对各种回收处理技术的优缺点进行对比,对老化原油回收处理技术的发展趋势提出了展望。     

Clean production with membrane technology

 Membrane processes, because of unique, specialized, and cost-effective applications, have the potential of playing a significant role in preventing pollution from occurring in manufacturing plants. Opportunities are seen in resource recovery, species purification, and energy savings. Emerging technologies of membrane reactors that combine separation with reaction in one physical unit are important developments also. In this paper we discuss the scope of membrane technologies in industrial applications as well as hurdles that must be overcome. Received: 15 April 1998 / Accepted: 9 August 1998     

河北省太阳能产业可持续发展对策研究

针对太阳能产业发展现状,找出河北省太阳能产业发展过程中存在的问题,如产业环节附加值低、产用不平衡、缺乏激励政策、存在技术难题和污染、运维管理跟不上等。借鉴国内外成功经验,从光热和光电平衡发展、加大科技投入、加强政策和机制建设、实施多元化模式、控制产业污染、培养专业的运维队伍等几方面提出河北省太阳能产业可持续发展的对策。     

Mitigating Industrial Pollution Along the Atlantic Coast of Cameroon: An Overview of Government Efforts

Summary This paper presents an overview of the initiatives that have been formulated by the government of Cameroon to address the problem of industrial pollution. It also prescribes robust recommendations that could be employed to save the Atlantic coast of Cameroon from industrial pollutants. After the participation of Cameroon in the Earth Summit in Rio de Janeiro in 1992, the government took a significant step to overhaul its institutional framework, legal framework and policy framework vis-à-vis the regulation of industrial pollution. Under the auspices of the United Nation Industrial Development Organisation (UNIDO), the Gulf of Guinea Large Marine Ecosystem Project aimed at sustaining the health of the Atlantic coast of Cameroon by ensuring treatment of industrial wastes, oil spills, sewage and heavy metals was implemented (1995–1999). Based upon careful analysis, however, the paper argues that these efforts have had little or no discernable impacts and that industrial activities along the Atlantic coast of Cameroon are still a major threat to safety, health and the environment. With a considerable number of hurdles that still persist, sufficient environmental improvement in industrial pollution along the Atlantic coast of Cameroon is far-fetched. Nevertheless, the paper concludes that marked environmental improvement can be obtained if: (i) competent personnel are appointed in ministries that play an active role in mitigating industrial pollution (ii) research partnerships are forged with local universities (iii) industrial machinery and equipment are improved (iv) inter institutional conflicts are addressed (v) a more collaborative forum between stakeholders is established (vi) adequate monitoring is instituted. The provisions of this paper form the foundation of an ongoing research being conducted by the authors at Brandenburg University of Technology, Cottbus, Germany.     

污泥农用对土壤环境的影响

土地利用是解决城市污泥处理处置的有效途径之一,本文从土壤理化性质、重金属污染风险以及有机污染风险3方面综述城市污泥农用对土壤环境的影响。城市污泥利用为植物提供营养元素,改良土壤结构,提高土壤肥力。污泥施用年限的长短与土壤中重金属的含量高低关系不明显,导致土壤重金属含量增加的主要因素是污泥施用量和污泥中重金属含量。在正常...