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1.
Optimistic estimates suggest that only 30–70% of waste generated in cities of developing countries is collected for disposal. As a result, uncollected waste is often disposed of into open dumps, along the streets or into water bodies. Quite often, this practice induces environmental degradation and public health risks. Notwithstanding, such practices also make waste materials readily available for itinerant waste pickers. These ‘scavengers’ as they are called, therefore perceive waste as a resource, for income generation. Literature suggests that Informal Sector Recycling (ISR) activity can bring other benefits such as, economic growth, litter control and resources conservation. This paper critically reviews trends in ISR activities in selected developing and transition countries. ISR often survives in very hostile social and physical environments largely because of negative Government and public attitude. Rather than being stigmatised, the sector should be recognised as an important element for achievement of sustainable waste management in developing countries. One solution to this problem could be the integration of ISR into the formal waste management system. To achieve ISR integration, this paper highlights six crucial aspects from literature: social acceptance, political will, mobilisation of cooperatives, partnerships with private enterprises, management and technical skills, as well as legal protection measures. It is important to note that not every country will have the wherewithal to achieve social inclusion and so the level of integration must be ‘flexible’. In addition, the structure of the ISR should not be based on a ‘universal’ model but should instead take into account local contexts and conditions.  相似文献   

2.
The fluorescent lamp recycling sector is growing considerably in Europe due to increasingly strict regulations aimed at inciting the consumption of low energy light bulbs and their end-of-life management. Chemical risks were assessed in fluorescent lamp recycling facilities by field measurement surveys in France, highlighting that occupational exposure and pollutant levels in the working environment were correlated with the main recycling steps and processes.The mean levels of worker exposure are 4.4 mg/m3, 15.4 μg/m3, 14.0 μg/m3, 247.6 μg/m3, respectively, for total inhalable dust, mercury, lead and yttrium. The mean levels of airborne pollutants are 3.1 mg/m3, 9.0 μg/m3, 9.0 μg/m3, 219.2 μg/m3, respectively, for total inhalable dust, mercury, lead and yttrium. The ranges are very wide. Surface samples from employees’ skin and granulometric analysis were also carried out. The overview shows that all the stages and processes involved in lamp recycling are concerned by the risk of hazardous substances penetrating into the bodies of employees, although exposure of the latter varies depending on the processes and tasks they perform. The conclusion of this study strongly recommends the development of a new generation of processes in parallel with more information sharing and regulatory measures.  相似文献   

3.
This paper analyses the evolution of national solid waste policy in Peru and the increasing relevance of informal recycling. Despite this rise in relevance, source separation and incorporation of informal recyclers within municipal plans is still slow, and collection of mixed waste is being considered. Waste collection and transportation costs represent the main share in municipal budgets and this research calculates cost reductions as a result of informal recycling and waste picking. The city of Chiclayo in Peru is presented as a case study. The paper finds that so far, waste picking has resulted in a reduction of two collection rounds but not a reduction in the number of vehicles collecting waste. Looking to the future, recovery of the remaining materials will not have an effect on collection rounds and number of vehicles. The research concludes that synergy between municipal systems and informal recycling can be maximized if new operational conditions are implemented. It introduces the concepts of “critical work shift,” which is the time of the day when the system requires maximum quantity of resources (i.e. vehicle-hours), and “sensitivity to variations in waste amounts,” and proposes strategies to promote recycling based on these new operational concepts.  相似文献   

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5.
A mathematical model to calculate the recycle rates for packaging materials from the municipal solid wastes (MSW) built from the dry mass values that are obtained from the corresponding wet masses and their respective moisture contents is presented in this work. A possible universal methodology is also described to be used with the previous model so that reliable comparisons between indicators for different regions are feasible. Furthermore, this mathematical model demonstrates the effect of the moisture content of packaging materials on their recycling rates and constitutes a fundamental tool for operators and persons responsible for MSW management to define new policies and technical measures viewing the improvement of recycling rates. A theoretical study and the application of the model to the MEMSW of the Lisbon region shows that the moisture content of the mixed wastes plays a dominant role in the recycling rates of packaging materials such as paper, plastics and glass. Moreover, accounting for all relevant masses in the dry basis yields higher recycling rate values: increases of 32.8% for paper, 50% for plastics and 44.6% glass are observed.  相似文献   

6.
Informal recycling is a new and expanding low cost recycling practice in managing Waste Electrical and Electronic Equipment (WEEE or e-waste). It occurs in many developing countries, including China, where current gaps in environmental management, high demand for second-hand electronic appliances and the norm of selling e-waste to individual collectors encourage the growth of a strong informal recycling sector. This paper gathers information on informal e-waste management, takes a look at its particular manifestations in China and identifies some of the main difficulties of the current Chinese approach. Informal e-waste recycling is not only associated with serious environmental and health impacts, but also the supply deficiency of formal recyclers and the safety problems of remanufactured electronic products. Experiences already show that simply prohibiting or competing with the informal collectors and informal recyclers is not an effective solution. New formal e-waste recycling systems should take existing informal sectors into account, and more policies need to be made to improve recycling rates, working conditions and the efficiency of involved informal players. A key issue for China’s e-waste management is how to set up incentives for informal recyclers so as to reduce improper recycling activities and to divert more e-waste flow into the formal recycling sector.  相似文献   

7.
In strategic end-of-life electrical and electronic equipment (EoL EEE) management, it has become important to not only avoid the negative environmental impacts but also enhance the positive effects of secondary resource utilization. This is especially true in emerging countries such as China, where medium- to long-term increases in the amount of EoL EEE generation are projected. This study aims to assess the resource availability potential for EoL EEE recycling based on penetration scenarios for formal and/or informal treatment options in China. We categorized substances contained in EoL television sets and personal computers into environmental, resource, and economic aspects under consideration of product transitions. Barium and copper have a high negative potential impact on human health and/or the ecosystem. Focusing on metals with a high resource potential, the resource availability is assessed under different treatment options using characterization factors identified through a life-cycle impact assessment method, the ReCiPe 2008. The results suggest that copper and lead recycling could alleviate the increase in mining costs of resource utilization. Scenario analysis for penetration of formal and informal recycling options indicated that the difference in the alleviated mining costs between the status quo and short-term transition projections until 2030 corresponds to 2.1–2.4 billion dollars.  相似文献   

8.
Increased energy costs, social marketing campaigns, public subsidies, and reduced retail prices have dramatically increased the number of compact fluorescent lights (CFLs) installed worldwide. CFLs provide many benefits, but they contain a very small amount of mercury. Given the billions of CFLs in use worldwide, they represent a significant source of mercury unless CFLs are recycled and the mercury recovered in an environmentally sound manner. In the state of Maine (northeast United States), despite mandated recycling of CFLs and availability of free CFL recycling, the household CFL recycling rate is very low. A study was undertaken to identify the primary factors responsible for low recycling. The first step was to survey householders who use CFLs. The 520 survey responses indicated that insufficient knowledge regarding recycling and inconvenience of the collection system are the two primary factors for the low recycling rate. To validate these findings, the second step was an examination of the current collection system to assess (a) the knowledge requirements necessary for recycling and (b) the convenience of the collection system. The results of this examination validated that knowledge requirements were excessively difficult to fulfill and the collection system is not sufficiently convenient. Based on these results, waste managers should focus on increasing convenience and simplifying access to information when designing or improving household collection and recycling of CFLs.  相似文献   

9.
Vocational Education and Training (VET) is an essential tool for providing waste management and recycling workers with the necessary skills and knowledge needed to beneficially influence their own employment and career development; and to also ensure productivity and safe working conditions within the organisations in which they are employed. Current training opportunities within Queensland for the sector are limited and not widely communicated or marketed; with other States, particularly Victoria and New South Wales, realising higher numbers of VET enrollments for waste management courses. This paper presents current VET opportunities and trends for the Queensland waste management sector. Results from a facilitated workshop to identify workforce requirements and future training needs organised by the Waste Contractors and Recyclers Association of Queensland (WCRAQ) are also presented and discussion follows on the future training needs of the industry within Queensland.  相似文献   

10.
In this study biogas and high quality digestate were recovered from winery waste (wine lees) through anaerobic co-digestion with waste activated sludge both in mesophilic and thermophilic conditions. The two conditions studied showed similar yields (0.40 m3/kgCODfed) but different biological process stability: in fact the mesophilic process was clearly more stable than the thermophilic one in terms of bioprocess parameters.The resulting digestates showed good characteristics for both the tested conditions: heavy metals, dioxins (PCDD/F), and dioxin like bi-phenyls (PCBs) were concentred in the effluent if compared with the influent because of the important reduction of the solid dry matter, but remained at levels acceptable for agricultural reuse. Pathogens in digestate decreased. Best reductions were observed in thermophilic condition, while at 37 °C the concentration of Escherichia coli was at concentrations level as high as 1000 UFC/g. Dewatering properties of digestates were evaluated by means of the capillary suction time (CST) and specific resistance to filtration (SRF) tests and it was found that a good dewatering level was achievable only when high doses of polymer (more than 25 g per kg dry solids) were added to sludge.  相似文献   

11.
循环冷却水系统中物质的转化规律及提高浓缩倍率的措施   总被引:3,自引:1,他引:2  
介绍了城市污水处理厂二级出水回用于循环冷却水系统时,系统中几种物质的转换以及不同浓缩倍率对铜试片的腐蚀速率。采用混凝+超滤+反渗透的旁路系统工艺,降低循环水系统中物质的浓度,可以使系统的浓缩倍率达到4。  相似文献   

12.
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As part of the EU Life + NOVEDI project, a new eco-efficient recycling route has been implemented to maximise resources and energy recovery from post-consumer waste glass, through integrated waste management and industrial production. Life cycle assessment (LCA) has been used to identify engineering solutions to sustainability during the development of green building products. The new process and the related LCA are framed within a meaningful case of industrial symbiosis, where multiple waste streams are utilised in a multi-output industrial process. The input is a mix of rejected waste glass from conventional container glass recycling and waste special glass such as monitor glass, bulbs and glass fibres. The green building product is a recycled foam glass (RFG) to be used in high efficiency thermally insulating and lightweight concrete. The environmental gains have been contrasted against induced impacts and improvements have been proposed. Recovered co-products, such as glass fragments/powders, plastics and metals, correspond to environmental gains that are higher than those related to landfill avoidance, whereas the latter is cancelled due to increased transportation distances. In accordance to an eco-efficiency principle, it has been highlighted that recourse to highly energy intensive recycling should be limited to waste that cannot be closed-loop recycled.  相似文献   

14.
15.
发展循环经济,创建节约型社会,是贯彻落实科学发展观的必然要求,体现了以人为本、可持续发展的发展理念,顺应当今世界的发展潮流。为此,本刊特开设“循环经济专题讲座”栏目,介绍循环经济理念的由来、涉足的领域及国内外的发展动态。为广大读者了解循环经济的相关知识、树立循环经济理念搭建一个学习的平台。  相似文献   

16.
The possibility of using incinerator bottom ash as a substitute for natural aggregates was investigated. Rough, porous surface of bottom ash, which diminishes the strength of solidified products, was improved by colloidal silica solution. As a result, a significant increase of mechanical strength was accomplished by a slight amount of silica (<1 wt% to total). Moreover, pozzolanic reaction was induced in initial cement hydration due to the nano-particle size of about 20 nm in colloidal silica solution. Cylindrical specimens and bricks were prepared from bottom ash added to a colloidal silica (SiO2) solution and cement, and then their compressive strengths were evaluated. Cylindrical specimens showed an increase of approximately 60% in compressive strength when colloidal solution containing 4 wt% silica particles was sprayed onto the bottom ash. The strength of bricks containing colloidal silica was in excess of 20 MPa, which meets the requirement of construction materials. Results of leaching tests based on Toxicity Characteristic Leaching Procedure (TCLP) proved that the solidified bottom ash possessed good chemical stability.  相似文献   

17.
Journal of Material Cycles and Waste Management - In this paper, a detailed thermodynamic analysis of processing of electronic waste (e-waste), particularly printed circuit boards (PCB), through...  相似文献   

18.
This paper presents an overview of cell phone recycling programs currently available in the United States. At the same time, it also provides analyses of the current recycling situation and possible recycling alternatives for Brazil. Although there are several recycling options in the United States, collection rates are still only 10% of all potential devices because customers are not aware of these possibilities. The whole system is financially based on reselling refurbished cell phones and recycled materials to developing countries which represent an effective and strong market. Several recyclers offer funds to collection partners who are either charities or who work with charities while obtaining the materials that they need in order to run their operations. A mobile phone recycling system for Brazil considering the United States experience and the Extended Producer Responsibility (EPR) principle is suggested. A deposit/refund/advance-recycling fee is proposed which might be implemented as a voluntary industrial initiative managed by PRO Brazil, a producer responsibility organization. One widespread public–private agreement will integrate all mobile phone stakeholders, and environmental education actions and promotional events will promote citizen’s participation.  相似文献   

19.
Floor dusts from Vietnamese end-of-life vehicle (ELV)-processing households were investigated to elucidate the contamination levels and exposure risk of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and dioxin-related compounds (DRCs). The concentrations were in order of PBDEs (260–11,000, median 280 ng/g overall) > PCBs (19–2200, median 140 ng/g) > dioxin-like PCBs (8.8–450, median 22 ng/g) ? polybrominated dibenzo-p-dioxin/dibenzofurans (PBDD/Fs, 2000–28,000, median 8500 pg/g) > polychlorinated dibenzo-p-dioxin/dibenzofurans (PCDD/Fs, 440–4100, median 1800 pg/g) > MoBPCDD/Fs (1.9–1200, median 250 pg/g). Concentrations of PCBs and DRCs were higher than those reported for Vietnamese urban houses, indicating ELV processing as a significant source of these contaminants. Higher concentrations of PCBs relative to PBDEs suggest the abundance of old electrical capacitors/transformers in ELVs. The PBDD/F and PCDD/F profiles were indicative of DecaBDE-containing materials and combustion sources, respectively. PBDFs, PCDFs and DL-PCBs were the most important dioxin-like toxic equivalent (TEQ) contributors. The estimated PCB and TEQ intake doses from dust ingestion approached or exceeded the reference doses for children living in some ELV-processing households, indicating potential health risk. More comprehensive risk assessment of the exposure to PCBs and DRCs is required for residents of informal ELV recycling sites.  相似文献   

20.
<正>1供销合作社系统具有比较健全的再生资源回收网络,有利于再生资源的有效集中和高效利用我国人口众多,人均资源占有量远低于世界平均水平,重要资源短缺已成为制约经济社会发展的重要因素。再生资源回收利用作为一个传统行业,在建设资源节约型与环境友好型社会的新的历史时期,越来越引起各级政府的高度重视和全社会的广泛支持。  相似文献   

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