Material cycles in Asia: especially the recycling loop between Japan and China

In this article, we clarify the current status of Japanese exports and Chinese imports of secondary resources. A total of around 10 million metric tons (t) of secondary resources are exported annually from Japan to China, Hong Kong, and Korea. Hong Kong plays the role of a transshipment point, especially regarding the trade in plastic waste, and China imports much from the USA and Japan, often through Hong Kong. The secondary resources exported from Japan include both byproducts from manufacturing processes and end-of-life products or materials. The great demand in China, and the difference in prices between countries, drive this transboundary shipment, although Japan has enacted various recycling laws that were implicitly intended to promote domestic recycling. In China, the imported secondary resources are recycled, usually by means of primitive and low-cost hand labor. The greatest concern is whether there are still improper (illegal or polluting) recycling activities in China. International material cycles should prevent environmental pollution and ensure efficient resource utilization. To that end, the following measures are needed: cooperative control of the trade of secondary resources between countries, the alignment of domestic laws with the regulations in other countries based on the actual trade activities, and the realization of sound practices for global resources management.     

废钢铁在钢铁行业中应用前景研究

废钢铁是我国物资回收与再生资源利用体系中的重要资源,也是非常重要的战略性资源,是钢铁工业最主要的两种原料之一(另一种是铁矿石)。与铁矿石相比,废钢铁更符合绿色可持续发展的需要和钢铁行业超低排放政策的要求,未来废钢铁资源在钢铁工业发展中的重要性可能会不断提升。着重探讨了未来10年废钢铁资源产生量的变化趋势,以及对钢铁工业原料结构变化的影响。未来中国的废钢铁资源可能不仅能满足自身钢铁工业发展的需要,同时也可能为世界钢铁工业的发展提供重要的原料。     

Recycling plastics from automotive shredder residues: a review

Automotive shredder residue (ASR) is an inevitable by-product of car recycling, i.e. removal of all liquids and hazardous or valuable components from the car and shredding of the hulk, followed by the recovery of steel, iron, and non-ferrous scrap. The European Union (EU) ELV Directive requires attaining higher recovery and recycling rates, resulting in a reduction of the amount of ASR going to landfill. The most plausible methods to achieve a considerable reduction of ASR are as follows: either recycling of separated materials and dismantled bulky parts, such as bumpers, dashboards, cushions, and front and rear windows, or else systematic sorting of the commingled and size-reduced materials, resulting from shredding. After a brief comparison of the actual situation in the EU, the USA, and Japan, the characteristics of actual ASR are reviewed, as well as some of the most prominent efforts made to separate and recycle specific fractions, such as polyolefins, ABS, or polyurethane. Attention is paid to some major players in the EU and to some of the pitfalls that besiege these ventures.     

Comparing urban solid waste recycling from the viewpoint of urban metabolism based on physical input-output model: A case of Suzhou in China

Investigating impacts of urban solid waste recycling on urban metabolism contributes to sustainable urban solid waste management and urban sustainability. Using a physical input-output model and scenario analysis, urban metabolism of Suzhou in 2015 is predicted and impacts of four categories of solid waste recycling on urban metabolism are illustrated: scrap tire recycling, food waste recycling, fly ash recycling and sludge recycling. Sludge recycling has positive effects on reducing all material flows. Thus, sludge recycling for biogas is regarded as an accepted method. Moreover, technical levels of scrap tire recycling and food waste recycling should be improved to produce positive effects on reducing more material flows. Fly ash recycling for cement production has negative effects on reducing all material flows except solid wastes. Thus, other fly ash utilization methods should be exploited. In addition, the utilization and treatment of secondary wastes from food waste recycling and sludge recycling should be concerned.     

Cathode ray tube (CRT) recycling: current capabilities in China and research progress

It is estimated that approximately 6,000,000 scrap TVs and 10,000,000 personal computers are generated each year in China. Cathode ray tubes (CRTs) from these machines consist of 85% glass (65% panel, 30% funnel and 5% neck glass). The leaded glass (funnel-24%, neck-30%) may seriously pollute the environment if it is not properly disposed of. In this paper, the past, current and future status of CRT dismantling technologies as well as the CRT glass recycling situation in China are presented and discussed. Recycling technology for waste CRTs in China is still immature. While the conventional CRT dismantling technologies have disadvantages from both economic and environmental viewpoints, some of the new and emerging treatments such as automatic optical sorting facilities that have been applied in developed countries offer advantages, and therefore should be transferred to China in the next few years to solve the CRT pre-processing problem. Meanwhile, because the demand for CRT glass closed-loop recycling is extremely limited, the authorities should take effective measures to improve CRT glass recycling rates and to facilitate a match to local conditions. Moreover, we also provide a broad review of the research developments in recycling techniques for CRT cullet. The challenge for the future is to transfer these environmentally friendly and energy-saving technologies into practice.     

报废汽车非金属材料资源化利用研究

随着大量汽车进入报废期,如何对报废汽车进行资源化再利用成为人们面临的重要课题。报废汽车上的非金属材料,由于种类多、组成复杂,资源化再利用的难度较大,大多被废弃,会造成资源浪费、环境污染等一系列问题。塑料、橡胶、玻璃是汽车中主要的非金属材料,这些物质的资源化利用,对改善环境、节约资源,具有极大的社会经济效益。着重对报废汽车中塑料、橡胶、玻璃主要非金属材料的资源化利用技术现状进行研究,探究提高其回收利用水平的思路,对报废汽车非金属材料的资源化再利用提供一定的参考。     

Recycling and recovery routes of plastic solid waste (PSW): A review

Plastic solid waste (PSW) presents challenges and opportunities to societies regardless of their sustainability awareness and technological advances. In this paper, recent progress in the recycling and recovery of PSW is reviewed. A special emphasis is paid on waste generated from polyolefinic sources, which makes up a great percentage of our daily single-life cycle plastic products. The four routes of PSW treatment are detailed and discussed covering primary (re-extrusion), secondary (mechanical), tertiary (chemical) and quaternary (energy recovery) schemes and technologies. Primary recycling, which involves the re-introduction of clean scrap of single polymer to the extrusion cycle in order to produce products of the similar material, is commonly applied in the processing line itself but rarely applied among recyclers, as recycling materials rarely possess the required quality. The various waste products, consisting of either end-of-life or production (scrap) waste, are the feedstock of secondary techniques, thereby generally reduced in size to a more desirable shape and form, such as pellets, flakes or powders, depending on the source, shape and usability. Tertiary treatment schemes have contributed greatly to the recycling status of PSW in recent years. Advanced thermo-chemical treatment methods cover a wide range of technologies and produce either fuels or petrochemical feedstock. Nowadays, non-catalytic thermal cracking (thermolysis) is receiving renewed attention, due to the fact of added value on a crude oil barrel and its very valuable yielded products. But a fact remains that advanced thermo-chemical recycling of PSW (namely polyolefins) still lacks the proper design and kinetic background to target certain desired products and/or chemicals. Energy recovery was found to be an attainable solution to PSW in general and municipal solid waste (MSW) in particular. The amount of energy produced in kilns and reactors applied in this route is sufficiently investigated up to the point of operation, but not in terms of integration with either petrochemical or converting plants. Although primary and secondary recycling schemes are well established and widely applied, it is concluded that many of the PSW tertiary and quaternary treatment schemes appear to be robust and worthy of additional investigation.     

Comparisons of four categories of waste recycling in China's paper industry based on physical input-output life-cycle assessment model

Waste recycling for paper production is an important component of waste management. This study constructs a physical input-output life-cycle assessment (PIO-LCA) model. The PIO-LCA model is used to investigate environmental impacts of four categories of waste recycling in China’s paper industry: crop straws, bagasse, textile wastes and scrap paper. Crop straw recycling and wood utilization for paper production have small total intensity of environmental impacts. Moreover, environmental impacts reduction of crop straw recycling and wood utilization benefits the most from technology development. Thus, using crop straws and wood (including wood wastes) for paper production should be promoted. Technology development has small effects on environmental impacts reduction of bagasse recycling, textile waste recycling and scrap paper recycling. In addition, bagasse recycling and textile waste recycling have big total intensity of environmental impacts. Thus, the development of bagasse recycling and textile waste recycling should be properly limited. Other pathways for reusing bagasse and textile wastes should be explored and evaluated. Moreover, imports of scrap paper should be encouraged to reduce large indirect impacts of scrap paper recycling on domestic environment.     

Material flows of end-of-life home appliances in Japan

In Japan, the Law for the Recycling of Specified Kinds of Home Appliances came into effect in April 2001. This law aims to introduce appropriate waste treatment and promote the efficient use of resources so that we can achieve a sound material-cycle society. The law introduces a new framework for recycling that places obligations principally on the manufacturers and retailers of home appliances. Material flow analysis of this new framework is essential for evaluation of the system and for finding any problems that may exist. We therefore analyzed the material flows in facilities that recycle electrical home appliances. The mass balances in the recycling facilities were appropriately estimated. Then the potential destinations were surveyed and analyzed, even though the legal framework does not include flows after the recycling facilities. The potential destination after the facilities varies and depends on both the economy and the related regulations. Currently, considerable amounts of recovered materials are exported and recycled. However, the sustainability of these trades is unknown. Therefore, we should keep a close eye on the situation and make sure that our recycling system is adaptable to meet any future changes.     

加快废钢产业发展 促进钢铁资源循环利用

分析了废钢的应用现状及应用不足的原因,为加快废钢产业发展提出建议。提出为适应当今钢铁工业节能、降耗、环保等方面的发展要求,应大力发展废钢产业,加快废钢资源利用,促进钢铁资源循环利用,实现我国钢铁工业的可持续发展．     

Characterization of shredded television scrap and implications for materials recovery

Characterization of TV scrap was carried out by using a variety of methods, such as chemical analysis, particle size and shape analysis, liberation degree analysis, thermogravimetric analysis, sink-float test, and IR spectrometry. A comparison of TV scrap, personal computer scrap, and printed circuit board scrap shows that the content of non-ferrous metals and precious metals in TV scrap is much lower than that in personal computer scrap or printed circuit board scrap. It is expected that recycling of TV scrap will not be cost-effective by utilizing conventional manual disassembly. The result of particle shape analysis indicates that the non-ferrous metal particles in TV scrap formed as a variety of shapes; it is much more heterogeneous than that of plastics and printed circuit boards. Furthermore, the separability of TV scrap using density-based techniques was evaluated by the sink-float test. The result demonstrates that a high recovery of copper could be obtained by using an effective gravity separation process. Identification of plastics shows that the major plastic in TV scrap is high impact polystyrene. Gravity separation of plastics may encounter some challenges in separation of plastics from TV scrap because of specific density variations.     

Current recycling regulations and technologies for the typical plastic components of end-of-life passenger vehicles: a meaningful lesson for China

China became the largest automotive producer and the biggest automobile market in the world in 2009, but the scrap vehicle recycling industry is still in its beginning stage. Especially, the scrapped plastic parts recycling technology lags behind developed countries. Therefore, in-depth studies on the recycling of automotive plastics are significant and beneficial for environmental protection, energy conservation and the sustainable development of the Chinese automotive plastic industry. In this article, automotive plastic components recycling-related rules and regulations about developed countries and China are discussed first. According to the passenger vehicle plastic part types, the recycling technologies for typical plastic components of end-of-life passenger vehicle are analyzed comprehensively. Based on the combination of contemporary domestic and foreign plastic recycling technology and the result of the current research, the problems and future development for the ELVs plastic recycling industry in China are deliberated, at the same time, some constructive ideas and suggestions for the industry are provided.     

经济转型中的中国废钢铁投资市场

废钢铁产业是我国再生资源产业的主体,其节能减排、低碳环保和不可替代的钢铁原料功效十分显著。阐述了我国废钢铁产业在经济转型中的主导地位、应用价值、投资环境及今后的发展战略。指出我国经济发展方式的转变,赋予了废钢铁产业良好的发展机遇和重大的历史使命,中国废钢产业具有良好的投资市场和巨大的发展空间。     

Time bomb or hidden treasure? Characteristics of junk TVs and of the US households who store them

Within the growing stockpile of electronic waste (e-waste), TVs are especially of concern in the US because of their number (which is known imprecisely), their low recycling rate, and their material content: cathode ray tube televisions contain lead, and both rear projection and flat panel displays contain mercury, in addition to other potentially toxic materials. Based on a unique dataset from a 2010 survey, our count models show that pro-environmental behavior, age, education, household size, marital status, gender of the head of household, dwelling type, and geographic location are statistically significant variables for explaining the number of broken or obsolete (junk) TVs stored by US households. We also estimate that they are storing approximately 84.1 million junk TVs, which represents 40 pounds of scrap per household. Materials in each of these junk TVs are worth $21 on average at January 2012 materials prices, which sets an upper bound on collecting and recycling costs. This information should be helpful for developing more effective recycling strategies for TVs in the e-waste stream.     

Status quo of e-waste management in mainland China

In China, the use and obsolescence of both electronic and electrical equipment have increased rapidly in recent years. China has also begun to take measures to cope with this problem since it began experiencing a rapid process of industrialization and urbanization in the 1990s. In this paper, the profile of the electrical and electronic waste (e-waste) problem in China is depicted from such aspects as domestic e-waste and imported e-waste, along with their recycling systems, policies, and regulations. Based on statistics of the consumption of major household appliances and personal computers, a forecast is made of the numbers of obsolete major household appliances and personal computers. The results show that currently the number of electrical and electronic products in use in China is tremendous. An investigation on household appliances and personal computers in Beijing was made to assess the use and obsolescence of these products. Also, the legal issues relating to e-waste in China are summarized, and these will be the juristic foundation for the solution of e-waste problems.     

International aspects of recycling of electrical and electronic equipment: material circulation in the East Asian region

This article examines the present circumstances of recycling of end-of-life electrical and electronic equipment discarded in Japan from the domestic and international viewpoints of material circulation. It is pointed out that some of the discarded items are absorbed into an invisible flow by informal economic activities, being exported in the form of secondhand equipment and secondary materials. Since the equipment has a pollution potential as well as a resource potential, it is anticipated that the pollution potential may possibly be realized if the equipment is mishandled at recycling plants in developing countries. To reduce the invisible flow as much as possible and to reduce the pollution potential from diffusion in developing countries, a policy tool such as extended producer responsibility should be applied to retailers of the equipment, as well as to producers.     

Cross-cultural comparison of concrete recycling decision-making and implementation in construction industry

Waste management is pressing very hard with alarming signals in construction industry. Concrete waste constituents major proportions of construction and demolition waste of 81% in Australia. To minimize concrete waste generated from construction activities, recycling concrete waste is one of the best methods to conserve the environment. This paper investigates concrete recycling implementation in construction. Japan is a leading country in recycling concrete waste, which has been implementing 98% recycling and using it for structural concrete applications. Hong Kong is developing concrete recycling programs for high-grade applications. Australia is making relatively slow progress in implementing concrete recycling in construction. Therefore, empirical studies in Australia, Hong Kong, and Japan were selected in this paper. A questionnaire survey and structured interviews were conducted. Power spectrum was used for analysis. It was found that “increasing overall business competitiveness and strategic business opportunities” was considered as the major benefit for concrete recycling from Hong Kong and Japanese respondents, while “rising concrete recycling awareness such as selecting suitable resources, techniques and training and compliance with regulations” was considered as the major benefit from Australian respondents. However, “lack of clients’ support”, “increase in management cost” and “increase in documentation workload, such as working documents, procedures and tools” were the major difficulties encountered from Australian, Hong Kong, and Japanese respondents, respectively. To improve the existing implementation, “inclusion of concrete recycling evaluation in tender appraisal” and “defining clear legal evaluation of concrete recycling” were major recommendations for Australian and Hong Kong, and Japanese respondents, respectively.     

Leaching behaviour of different scrap materials at recovery and recycling companies: Full-, pilot- and lab-scale investigation

Scrap material recovery and recycling companies are confronted with waste water that has a highly fluctuating flow rate and composition. Common pollutants, such as COD, nutrients and suspended solids, potentially toxic metals, polyaromatic hydrocarbons and poly chlorinated biphenyls can exceed the discharge limits. An analysis of the leaching behaviour of different scrap materials and scrap yard sweepings was performed at full-scale, pilot-scale and lab-scale in order to find possible preventive solutions for this waste water problem. The results of these leaching tests (with concentrations that frequently exceeded the Flemish discharge limits) showed the importance of regular sweeping campaigns at the company, leak proof or covered storage of specific scrap materials and oil/water separation on particular leachates. The particulate versus dissolved fraction was also studied for the pollutants. For example, up to 98% of the polyaromatic hydrocarbons, poly chlorinated biphenyls and some metals were in the particulate form. This confirms the (potential) applicability of sedimentation and filtration techniques for the treatment of the majority of the leachates, and as such the rainwater run-off as a whole.     

广州市推动再生资源回收利用行业转型的有效探索

广州市作为国家再生资源回收体系建设试点城市,在大力发展循环经济、推进再生资源回收利用网络体系建设方面进行了先行先试探索,取得了明显成效。“广州模式”对推进广东省加快转型升级具有启示借鉴意义。     

A Comparative Overview Of Recycling In London And Hamburg

The level of recycling for household waste is significantly higher in Hamburg than in London, yet the extent of materials recovery in both cities is well below technically achievable levels. This paper shows that the higher level of recycling in Hamburg can be accounted for by three main factors: a higher density of recycling facilities combined with the use of more sophisticated collection systems such as a dual-bin service for putrescible wastes; a unified administrative structure for waste management under direct control of an elected regional government; and finally, a system of proportional representation in local government allowing environmentalist political demands to be directly translated into public policy. Despite these differences however, both cities face difficulties with the expansion of recycling derived from the weakness of the secondary materials market, the lack of legislative control over the size and composition of the waste stream, the fiscal constraints on local government and the expense of comprehensive recycling programmes in comparison with alternative forms of waste disposal. This paper concludes that the high cost of recycling presents a fundamental political dilemma for sustainable waste management policy in developed economies.