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1.
International aspects of recycling of electrical and electronic equipment: material circulation in the East Asian region 总被引:2,自引:1,他引:2
Eiji Hosoda 《Journal of Material Cycles and Waste Management》2007,9(2):140-150
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. 相似文献
2.
An attempt has been made to establish an approach and a methodology to quantify electronic waste (e-waste) in India. The study
was limited to personal computers (PCs) and televisions (TVs) within the state boundaries of Delhi and in selected areas in
the National Capital Region (NCR). Material flow analysis was used to establish an e-waste trade value chain, where cathode
ray tubes (CRTs) were tracked in the e-waste dismantling stream of the CRT regunning process. The market supply method was
used to estimate the theoretical amount of e-waste for each item. Sensitivity analysis was carried out for PCs, using 5 years
and 7 years as the average life, and for TVs, using 10 years and 12 years as the average life. Externalities such as e-waste
entering the study area from outside were factored into the final e-waste analysis. Sensitivity analysis on the average life
also factored in elements of active usage, reuse, and storage of electronic items and consumer behavior into assumptions about
the obsolescence rate in market supply method. A primary survey indicated an output of 1800–2100 CRTs per day from all regunning
units in the study area. This range validated the theoretical output for an average life of 7 years for a PC and 12 years
for a TV. Using this approach, e-waste was estimated to reach 2 million units from the domestic market by 2010. 相似文献
3.
The objective of this paper is to estimate the future projection of computer waste in India and to subsequently analyze their flow at the end of their useful phase. For this purpose, the study utilizes the logistic model-based approach proposed by Yang and Williams to forecast future trends in computer waste. The model estimates future projection of computer penetration rate utilizing their first lifespan distribution and historical sales data. A bounding analysis on the future carrying capacity was simulated using the three parameter logistic curve. The observed obsolete generation quantities from the extrapolated penetration rates are then used to model the disposal phase. The results of the bounding analysis indicate that in the year 2020, around 41–152 million units of computers will become obsolete. The obsolete computer generation quantities are then used to estimate the End-of-Life outflows by utilizing a time-series multiple lifespan model. Even a conservative estimate of the future recycling capacity of PCs will reach upwards of 30 million units during 2025. Apparently, more than 150 million units could be potentially recycled in the upper bound case. However, considering significant future investment in the e-waste recycling sector from all stakeholders in India, we propose a logistic growth in the recycling rate and estimate the requirement of recycling capacity between 60 and 400 million units for the lower and upper bound case during 2025. Finally, we compare the future obsolete PC generation amount of the US and India. 相似文献
4.
《Waste management & research》1991,9(5):415-423
Wastes have been aptly defined as “items i.e. resources, that have been discarded because their possessors no longer have an apparent use for them”. Accordingly, “wastes” have a significance only in relation to the items and those who have discarded them. The discarded items now are resources awaiting reclamation. Reclamation usually involves either salvage or conversion—or in modern terminology, “reuse” or “recycling”. Reclamation for reuse consists in refurbishing or other upgrading without significantly altering original form and composition. Examples of wastes amenable to reuse are containers (bottles, etc.), cartons and repairable tires. With “recycling” (i.e. conservation), the discarded items are processed such that they become raw material i.e. resources in the manufacture of “new” products. The variety of processes is wide, ranging from simply physical (grinding) through thermal (melting, gasification, combustion), to biological (composting, biogasification, hydrolysis, microbial protein production). In the paper, reuse and recycling (conversion) are evaluated in terms of advantages and disadvantages (limitations) and their respective technologies are described and discussed in detail. 相似文献
5.
Material and heavy metal balance in a recycling facility for home electrical appliances 总被引:6,自引:0,他引:6
Collection and recycling of home electrical appliances was started in Japan in 2001 under a new recycling law. The law is aimed at promoting material recycling and at reducing the amount of waste to be landfilled. End of life products are processed by manual disassembly, shredding, and separation in 38 recycling facilities. The authors conducted a questionnaire survey and interviewed at some facilities to obtain information on process flow and material balance. By using the detailed records offered by one facility and by estimating the composition of recovered components, the material balance in the facilities was determined for four typical recycling processes. The heavy metal content of the recovered components was analyzed, then metal flow in the process was determined for each scenario. As a result, it was concluded that emissions to the environment of most heavy metals have been substantially reduced by the new recycling system, while a modest improvement in the rate of material recovery has been achieved. 相似文献
6.
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. 相似文献
7.
M. Masud K. Khan Carlos J. Hilado Sushant Agarwal Rakesh K. Gupta 《Journal of Polymers and the Environment》2007,15(3):188-194
Acrylonitrile–Butadiene–Styrene (ABS), Polycarbonate (PC) and their alloys are widely used in automotive industry, computer
and equipment housings. With increasing disposal of end-of-life electronic equipment, there is also an increased demand for
recycling of these materials so that they do not pose environmental challenge as solid waste. One of the recycling approaches
is mechanical recycling of these thermoplastics where recycled plastic is melt blended with virgin materials to obtain a high
quality product. Besides obtaining desirable mechanical properties, such blends should also conform to fire safety standards.
In this work, a series of blends were prepared using PC and ABS recovered from discarded computers and virgin materials using
a twin-screw extruder. Their flammability properties were evaluated using burner flammability tests and Ohio State University
(OSU) release rate tests. It was found that the extinguishing time, burning extent and weight loss appears to progressively
decrease with the addition of both virgin or recycled PC to virgin or recycled ABS. It was also seen that the addition of
the 70% of PC, virgin or recycled, to ABS virgin or recycled, appears to significantly decrease heat release and smoke evolution.
The results of this study indicate that recycled polycarbonate can be used as an additive for virgin or recycled ABS, as a
means of giving flame resistance to ABS in high-value applications. This result is significant when related to the result
obtained by a separate study indicating that up to 25% of recycled material can be used without degradation of mechanical
properties in the presence of 15% short glass fiber reinforcement. 相似文献
8.
WEEE flow and mitigating measures in China 总被引:4,自引:0,他引:4
The research presented in this paper shows that Waste Electrical and Electronic Equipment (WEEE) issues associated with home appliances, such as TV sets, refrigerators, washing machines, air conditioners, and personal computers, are linked in the WEEE flow and recycling systems and are important to matters of public policy and regulation. In this paper, the sources and generation of WEEE in China are identified, and WEEE volumes are calculated. The results show that recycling capacity must increase if the rising quantity of domestic WEEE is to be handled properly. Simultaneously, suitable WEEE treatment will generate large volumes of secondary resources. Environmental problems caused by the existing recycling processes have been investigated in a case study. Problems mainly stem from open burning of plastic-metal parts and from precious metals leaching techniques that utilize acids. The existing WEEE flow at the national level was investigated and described. It became obvious that a considerable amount of obsolete items are stored in homes and offices and have not yet entered the recycling system. The reuse of used appliances has become a high priority for WEEE collectors and dealers because reuse generates higher economic profits than simple material recovery. The results of a cost analysis of WEEE flow shows that management and collection costs significantly influence current WEEE management. Heated discussions are ongoing in political and administrative bodies as to whether extended producer responsibilities policies are promoting WEEE recycling and management. This paper also discusses future challenges and strategies for WEEE management in China. 相似文献
9.
Current situation of used household batteries in Iran and appropriate management policies 总被引:1,自引:0,他引:1
Used household batteries are considered as hazardous wastes in many countries due to the potential environmental and human health risks associated with the heavy metals present in batteries. This article presents the current situation of waste household batteries and policies in Iran. Iran with more than 70 million people is a developing country where latest technologies like cell phones and laptops are in widespread use and battery consumption increases accordingly. The household battery demand in Iran has rapidly grown since 2001 and it is expected to increase more quickly in next years, due to increasing technological development. Based on the available data, more than 9800 metric tons of household batteries were imported into Iran in recent decade, with the market value of about US$ 42.6 million. At present, there is no program available in Iran regarding to collection, separation, recycling or safe disposal of used batteries. Therefore, almost all of the spent household are discarded into municipal solid waste (MSW) and sent to sanitary landfills. Appropriate policies to meet safe disposal of household batteries in Iran is also discussed in this investigation. 相似文献
10.
Recycling and reuse of industrial wastes in Taiwan 总被引:1,自引:0,他引:1
Eighteen million metric tons of industrial wastes are produced every year in Taiwan. In order to properly handle the industrial wastes, the Taiwan Environmental Protection Administration (Taiwan EPA) has set up strategic programs that include establishment of storage, treatment, and final disposal systems, establishment of a management center for industrial wastes, and promotion of recycling and reuse of industrial wastes. The Taiwan EPA has been actively promoting the recycling and reuse of industrial wastes over the years. In July 1995 the Taiwan EPA amended and promulgated the Criteria for the Industrial Waste Storage, Collection and Processing Facility, July, 1995 that added articles related to general industrial waste recycling and reuse. In June 1996 the Taiwan EPA promulgated the Non-listed General Industrial Waste Reuse Application Procedures, June, 1996, followed by the Regulations Governing the Permitting of Hazardous Industrial Waste Reuse, June 1996, setting up a full regulatory framework for governing industrial waste reuse. To broaden the recycling and reuse of general industrial wastes, the Taiwan EPA has listed 14 industrial waste items for recycling and reuse, including waste paper, waste iron, coal ash, tempered high furnace bricks (cinder), high furnace bricks (cinder), furnace transfer bricks (cinder), sweetening dregs, wood (whole/part), glass (whole/part), bleaching earth, ceramics (pottery, brick, tile and cast sand), individual metal scraps (copper, zinc, aluminum and tin), distillery grain (dregs) and plastics. As of June 1999, 99 applications for reuse of industrial wastes had been approved with 1.97 million metric tons of industrial wastes being reused. 相似文献
11.
Amit Kapur Hendrik G. van Oss Gregory Keoleian Stephen E. Kesler Alissa Kendall 《Journal of Material Cycles and Waste Management》2009,11(2):155-165
A country-level stock and flow model for cement, an important construction material, was developed based on a material flow
analysis framework. Using this model, the contemporary cement cycle of the United States was constructed by analyzing production,
import, and export data for different stages of the cement cycle. The United States currently supplies approximately 80% of
its cement consumption through domestic production and the rest is imported. The average annual net addition of in-use new
cement stock over the period 2000–2004 was approximately 83 million metric tons and amounts to 2.3 tons per capita of concrete.
Nonfuel carbon dioxide emissions (42 million metric tons per year) from the calcination phase of cement manufacture account
for 62% of the total 68 million tons per year of cement production residues. The end-of-life cement discards are estimated
to be 33 million metric tons per year, of which between 30% and 80% is recycled. A significant portion of the infrastructure
in the United States is reaching the end of its useful life and will need to be replaced or rehabilitated; this could require
far more cement than might be expected from economic forecasts of demand for cement. 相似文献
12.
Sumikura Yuichiro Katsumi Takeshi 《Journal of Material Cycles and Waste Management》2022,24(4):1216-1227
Journal of Material Cycles and Waste Management - The status of material reuse and recycling in Japan is reviewed with an emphasis on the efforts by the national government. First, the national... 相似文献
13.
Usep Surahman Osamu Higashi Tetsu Kubota 《Journal of Material Cycles and Waste Management》2017,19(2):657-675
First, this paper evaluates the current building material stock and future demolition waste for urban residential buildings in the cities of Jakarta and Bandung using a material-flow analysis. The actual on-site building measurements were conducted in Jakarta (2012) and Bandung (2011), focusing particularly on unplanned houses, to obtain building material inventory data. A total of 297 houses were investigated in Jakarta, whereas 247 houses were measured in Bandung. Second, this paper analyses the embodied energy and CO2 emissions of building materials through an input–output analysis. The results show that, overall, the total material input intensity for the houses is 2.67 ton/m2 in Jakarta and 2.54 ton/m2 in Bandung. Two scenarios with zero and maximum reuse/recycling rates were designed to predict future demolition waste and the embodied energy/CO2 emissions of building materials in Jakarta. Closed- and open-loop material flows were applied. If the maximum reuse/recycling rates are applied to the closed- and open-loop material flows in Jakarta, then it would become possible to not only decrease the final disposal waste (from 123.9 to 2.1 million ton) but also reduce the corresponding embodied energy (from 247.8 to 192.1 PJ) and CO2 emissions (from 24.3 to 19.2 million ton CO2-eq) compared with the zero reuse/recycling scenario from 2012 to 2020. 相似文献
14.
Junya Yano Yasuhiro Hirai Kengo Okamoto Shin-ichi Sakai 《Journal of Material Cycles and Waste Management》2014,16(1):52-61
Since end-of-life vehicles (ELVs) contain toxic substances, they have to be treated properly. The purpose of this study was to obtain useful information for ELV management from the viewpoint of toxicity. We focused on lead as a representative toxic substance contained in vehicles and investigated the dynamic substance flow of lead contained in ELVs and its content in automobile shredder residue (ASR). A population balance model was used to estimate the number of ELVs generated between FYs (fiscal year) 1990–2020, employing a Weibull distribution for the lifespan distribution. Sixteen lead-containing components of the vehicle were considered. It was estimated that the annual number of ELVs generated would be 2.9 million as of FY2020. The results implied that it is hard to remove Pb completely. This is because 5,000–11,000 t-Pb will still remain in vehicles in use in FY2020 even though most components in new model vehicles could be replaced by lead-free alternatives. As of FY2010, the substance flow showed that Pb contained in ELVs amounted to 4,600–5,700 t-Pb. Of this, 13.2–14.0 % was contained in ASR. The Pb content in ASR could be dramatically decreased by FY2020, but it will continue to contain 240–420 mg-Pb/kg if the treatment system is not improved. 相似文献
15.
Yasundo Kurata Yoichi Watanabe Yusaku Ono Kiyoshi Kawamura 《Journal of Material Cycles and Waste Management》2005,7(1):38-47
We investigated the concentrations of wood preservatives in the wood chips produced in wood-waste processing facilities in 1988, 1998–1999, and 2001–2002. Among the wood preservatives used in the past in Japan, halophenols, including PCP, chlordane, and chlorpyrifos, had comparatively high detection rates and high average concentrations in the wood chips produced in 2001–2002. Aldrin and endrin were rarely detected, and DDT was already in low concentrations in those wood chips. Although several types of wood preservative were contained in the wood chips, their concentration levels depended on the sources of the wood wastes. In chips produced from wooden pallets, wooden forms for concrete working, or wood discarded from nondemolition sources, no organochlorine wood preservatives were detected, and chlorpyrifos and chlorophenols were detected at one order of magnitude lower than the average concentrations in chips produced from wood wastes discarded in house demolitions. 相似文献
16.
Inaba Rokuta Tasaki Tomohiro Kawai Kosuke Nakanishi Shotaro Yokoo Yusuke Takagi Shigesada 《Journal of Material Cycles and Waste Management》2022,24(1):155-165
Journal of Material Cycles and Waste Management - Japan has been promoting 3R (reduce, reuse, and recycle) policies for several decades, but the recycling rate of the whole country has leveled off,... 相似文献
17.
We give an overview of the management systems of household hazardous waste (HHW) in Japan and discuss the management systems
and their risks. To get basic information, we conducted a survey of consumers to discover their behavior and awareness of
HHW items throughout the entire life cycle, which is made up of the purchase, use, and disposal of a product. The results
showed that many people hold end-of-life batteries, fluorescent lamps, empty spray cans, and others in their houses after
use. Also, the results showed that a lot of such waste items were discarded in waste streams different from those stipulated
by local governments. In particular, many people do not remove NiCd batteries inside products such as shavers or cordless
phones before discarding. On the other hand, people’s knowledge of and concern regarding the risks, collection, and recycling
of HHW were high. When information about the risks was specifically presented in the questionnaire, people tended to show
a more positive intention to participate in a collection and recycling system compared to those who were not presented with
such information. Our studies on NiCd batteries and fluorescent lamps showed that it is important to collect and recycle HHW
to control the domestic and international flows of cadmium and mercury. 相似文献
18.
Municipal services in the Palestinian Authority (PA) areas, including the West Bank and Gaza Strip (WBGS), are facing serious difficulties that have been intensified following the outbreak of the Palestinian uprising in late September 2000. The solid waste management services, being the most essential services provided by the municipalities and village councils, are mostly affected by the ongoing harsh situation and hence proper solutions that take into account the actual amount of generated municipal solid waste and its composition is a pre-requisite for planning proper treatment. Hence, a study was carried out to identify the actual status of solid waste in eight West Bank districts. A social survey was also conducted to collect information concerning the level of public awareness among communities surveyed to the perception of solid waste recycling and reuse. The results of the survey conducted in 2001–2002 were later reviewed during July–October 2008 to assess if the trend of domestic solid waste generation had changed. Based on the survey and post-assessment, it is found that political and economic conditions have both significantly impacted the trend of generated municipal solid waste and since no improvements in either condition are forthcoming, it is concluded that survey results could be used in a planning study. A possible handling of the generated wastes may entail transferring the recyclable waste to Israeli recycling industries, and in constructing three composting plants in different accessible locations in the West Bank. 相似文献
19.
Casares ML Ulierte N Matarán A Ramos A Zamorano M 《Waste management (New York, N.Y.)》2005,25(10):1075-1082
ASEGRA is an industrial area in Granada (Spain) with important waste management problems. In order to properly manage and control waste production in industry, one must know the quantity, type, and composition of industrial wastes, as well as the management practices of the companies involved. In our study, questionnaires were used to collect data regarding methods of waste management used in 170 of the 230 businesses in the area of study. The majority of these companies in ASEGRA are small or medium-size, and belong to the service sector, transport, and distribution. This was naturally a conditioning factor in both the type and management of the wastes generated. It was observed that paper and cardboard, plastic, wood, and metals were the most common types of waste, mainly generated from packaging (49% of the total volume), as well as material used in containers and for wrapping products. Serious problems were observed in the management of these wastes. In most cases they were disposed of by dumping, and very rarely did businesses resort to reuse, recycling or valorization. Smaller companies encountered greater difficulties when it came to effective waste management. The most frequent solution for the disposal of wastes in the area was dumping. 相似文献
20.
Shinsuke Murakami Atsushi Terazono Naoya Abe Yuichi Moriguchi Hideki Miyakawa 《Journal of Material Cycles and Waste Management》2006,8(1):46-55
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. 相似文献