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1.
In this study, the environmental impact of recycling portable nickel–cadmium (NiCd) batteries in Sweden is evaluated. A life cycle assessment approach was used to identify life cycle activities with significant impact, the influence of different recycling rates and different time boundaries for emissions of landfilled metals. Excluding the user phase of the battery, 65% of the primary energy is used in the manufacture of batteries while 32% is used in the production of raw materials. Metal emissions from batteries to water originate (96–98%) from landfilling and incineration. The transportation distance for the collection of batteries has no significant influence on energy use and emissions. Batteries manufactured with recycled nickel and cadmium instead of virgin metals have 16% lower primary energy use. Recycled cadmium and nickel metal require 46 and 75% less primary energy, respectively, compared with extraction and refining of virgin metal. Considering an infinite time perspective, the potential metal emissions are 300–400 times greater than during the initial 100 years. From an environmental perspective, the optimum recycling rate for NiCd batteries tends to be close to 100%. It may be difficult to introduce effective incitements to increase the battery collection rate. Cadmium should be used in products that are likely to be collected at the end of their life, otherwise collection and subsequent safe storage in concentrated form seems to offer the best solution to avoid dissipative losses.  相似文献   

2.
The recovery of ferrous and non ferrous metals from the bottom ashes is a common practice in the most part of Europe, both for the environmental advantages of their recycle and to avoid problems of swelling and expansion that metals can cause when bottom ashes are reused in concrete production or in road construction. This paper focuses on metal recovery from bottom ashes produced in Municipal Solid Waste (MSW) incinerators, with a particular focus on aluminium. A forecasting model was developed in order to evaluate the quantity of aluminium scraps recoverable from the bottom ashes. The model was applied to the Italian situation but its validity can be extended to other countries. Focusing on Italy, by applying conventional technologies for the separation of non-ferrous metals, the amount of aluminium potentially recoverable from bottom ashes is estimated in the range from 16,500 to 21,000 tonnes at the year 2015, and from 19,000 to 28,500 tonnes at 2020.  相似文献   

3.
It is widely agreed that public support is vital to the success of most recycling schemes; the actions of householders are paramount to the success of sustainable waste policies. However, the success of recycling schemes is not just dependent on public participation; it is also dependent on careful planning, effective design and tailoring to local needs.This study has evaluated a kerbside recycling scheme in the north-west of England by comparing the recycling performance of those on alternate collections of residual waste and recyclates with those on weekly residual collections and fortnightly recyclate collections. Three data collection methodologies were adopted: postal questionnaires, set-out rate monitoring, and personal interviews with policy writers.The results demonstrated that alternate collections produce higher recycling set-out rates, suggesting that alternate collections will also generate higher recycling rates. The research showed that if designed and complemented by other services, then an alternate collection system is a realistic waste management approach. However, the local authority and the public appear to use different indicators of success for the scheme. The local authority uses governmental performance indicators (such as best value performance indicators—BVPIs) to measure success, whereas the public's indicators of success tend to focus more on issues such as required changes to established behaviours, convenience and personal preferences.A key recommendation from this study is that all local authorities should carry out local opinion surveys on an annual basis to supplement the BVPIs required by statute. This should help them to fill the information gaps in order to provide a comprehensive, up-to-date and user-responsive waste management service to the public.  相似文献   

4.
Recycling materials have always some degree of contamination. The presence of contaminations in the recycling streams causes a shift in the original composition of the materials to recycle. As a consequence, their quality may decrease with each recycling step. Additionally, lower quality resources are produced from resource streams that had initially a higher quality. These quality losses cannot be measured by mass balances, as the quality degradation cannot be translated by mass measures alone. To account all losses caused by recycling contaminations, all downstream recycling processes required to bring the materials back to the resource cycles must be included. This article describes a method to calculate the exergy content and exergy losses of metal solutions during recovery and recycling. The losses attributed to recycling, namely the material losses, the contamination losses with other metals, and the consequent need for dilution can be used as indicators of the quality loss of materials and of the efficiency of resource use in product systems. Therefore, exergy is proposed here as a measure of the efficiency of resources use.  相似文献   

5.
The paper describes the results of a municipal solid waste management planning based on an extensive utilization of material and substance flow analysis, combined with the results of specific life cycle assessment studies. The mass flow rates of wastes and their main chemical elements were quantified with a view to providing scientific support to the decision-making process and to ensure that the technical inputs to this process are transparent and rigorous. The role of each waste management option (recycling chains, biological and thermal treatments), as well as that of different levels of household source separation and collection (SSC), was quantitatively determined. The plant requirements were consequently evaluated, by assessing the benefits afforded by the application of high quality SSC, biological treatment of the wet organic fraction, and thermal treatment of unsorted residual waste. Landfill volumes and greenhouse gas emissions are minimized, toxic organic materials are mineralized, heavy metals are concentrated in a small fraction of the total former solid waste volume, and the accumulation of atmophilic metals in the air pollution control residues allows new recycling schemes to be designed for metals. The results also highlight that the sustainability of very high levels of SSC is reduced by the large quantities of sorting and recycling residues, amounts of toxic substances in the recycled products, as well as logistic and economic difficulties of obtaining very high interception levels. The combination of material and substance flow analysis with an environmental assessment method such as life cycle assessment appears an attractive tool-box for comparing alternative waste management technologies and scenarios, and then to support waste management decisions on both strategic and operating levels.  相似文献   

6.
In this study, the application of modern recycling technologies in accordance with the European and Greek legislation, aiming at the recovery of lead, polypropylene and sulfuric acid from spent lead (Pb)/acid batteries, is presented. The present state of their disposal and exploitation is also depicted. The international situation is reviewed, the general trends are marked and the main technologies related to lead/acid battery treatment are reported. General recommendations are given regarding the collection of spent batteries and the installation of a recycling plant in Greece. A sensitivity analysis is carried out in order to define the most significant parameters affecting the viability of a recycling scheme. The present study proves that a possible installation of a Pb/acid batteries recycling process unit, treating 17 000 t/year (estimated total quantity) and situated in the industrial area of the greater Athens region, seems to be economically profitable. The already existing operation of small-scale battery recycling plants, common in small countries, should be discouraged as they demonstrate a rather not environmentally acceptable recycling operation.  相似文献   

7.
The decision as to whether to recycle discarded objects or not has traditionally been made on a simple financial basis. However, over the last few years a popular movement has sprung up which regards recycling as a good in itself, and this movement finds itself at odds with the present financial basis for recycling. In this paper a rationale for recycling is worked out in an attempt to resolve this conflict. It is concluded that the normal market signals do not provide a proper basis for recycling decisions and that this market failure must be corrected by government intervention. However, this intervention should not take the form of uncritical support for recycling. Rather the societal objectives of individual recycling proposals should be identified and the proposal should then be evaluated in terms of whether it would achieve these objectives more effectively than some alternative action.  相似文献   

8.
The number of manufactured aircraft has been continuously increasing worldwide because of the high demand for airline transportation. During manufacturing, many advanced materials and devices are used to build various sizes and shapes of aircraft. However, most of these materials and devices require considerable energy and labor to produce, so reusing these at any life stage of the aircraft offers many economic and environmental benefits, and is considered lucrative and environmentally responsible. Several recyclable materials—composites, metals and alloys, wires, wood, paper, plastics, electronics, and avionics—emerge as waste streams during the manufacturing of aircraft. Many aircraft companies have been recycling these materials to remanufacture aircraft parts or other products for more sustainable production. In the present study, we evaluated the recycling efforts of local aircraft companies in Wichita, KS. These efforts were considered in terms of recycling efficiency/rate and environmental benefits. These included cradle-to-gate (CTG) life-cycle inventory analysis of the materials, carbon dioxide emissions, virgin material replacement with recycled materials, and natural resources usage. Our findings show that there exists a significant potential for contributions to sustainability as well as environmental and health benefits in the region from recycling by aircraft manufacturing plants.  相似文献   

9.
An experimental study of road building and recycling of used pavement has been conducted within the framework of a Life Cycle Analysis. Four equivalent asphalt concretes made with different recycling rates have been investigated during road construction. Airborne emissions, pollutant release over time and odor production related to asphalt laying have all been determined and compared among the various recycling rates. All of the results (VOC, PAH and odors), expressed in terms of concentrations and fluxes, exhibit quite monotonic variations with respect to the recycling rate. These results, however, did not reveal the same trend as a function of the recycling rate (increases or decreases), depending on the selected target parameter (VOC or PAH). Indicators have been proposed for a discussion of results that take into account: (i) raw material emissions with respect to the reference defined in the case of pavement without reclaimed asphalt; and (ii) emissions in each case from all material production sources.  相似文献   

10.
Economy-wide material flow accounting and analysis (EW-MFA) is considered a convenient tool for monitoring the vast range of issues related to the consumption of materials. As an increase in recycling is considered a crucial way of decreasing environmental pressures from this consumption, it makes sense to develop an indicator based on EW-MFA which would incorporate recycling flows. A prominent example of such an indicator is the cyclical use rate, which was developed by the Japanese Fundamental Plan for Establishing a Sound Material-Cycle Society.We calculated this indicator for the Czech Republic for 2002–2011 and proved that it can also be calculated for countries other than Japan, even though we encountered some unclear methodological issues related to specific features of the Czech waste management system. We further developed two modifications of the indicator taking into consideration that one purpose of the cyclical use rate is to express the ratio of consumption of secondary (recycled) materials and primary raw materials. We discussed these modifications and showed that overall cyclical use rate in the Czech Republic lags behind Japan both in terms of absolute value and trend development, although the indicator is higher for biomass in the Czech Republic. We also showed that this unfavorable evaluation is in contradiction with some classic waste indicators, such as treatment of waste by main treatment methods which is favorably evaluated in the Czech Republic. We concluded that it would be advisable to analyze measures for increasing recycling rates introduced by Japan and assess their possible transposition into the Czech Republic's institutional and legal framework for waste management.  相似文献   

11.
The growth of electronic waste (e-waste) is of increasing concern because of its toxic content and low recycling rates. The e-waste recycling infrastructure needs to be developed, yet little is known about people's willingness to fund its expansion. This paper examines this issue based on a 2004 mail survey of California households. Using an ordered logit model, we find that age, income, beliefs about government and business roles, proximity to existing recycling facilities, community density, education, and environmental attitudes are significant factors for explaining people's willingness to pay an advanced recycling fee (ARF) for electronics. Most respondents are willing to support a 1% ARF. Our results suggest that policymakers should target middle-aged and older adults, improve programs in communities with existing recycling centers or in rural communities, and consider public-private partnerships for e-waste recycling programs.  相似文献   

12.
Integrated smelter-refineries play an important role in the recovery of multiple metals from complex primary and secondary materials, and hence in closing metals cycles. Processes in these facilities are strongly interconnected, dynamic, and multifunctional, which challenges a typical representation in life cycle assessment (LCA). This is especially true when LCA is applied to calculate the environmental profile of single metals products.This study examines methodological requirements for assessing complex co-product systems using attributional LCA through a static, gate-to-gate inventory model that quantifies the environmental impacts of each of the metal products of an integrated precious metals smelter-refinery. The model is based on a large number of subprocesses and is formulated using detailed industry data, which allows quantification of the sensitivity of the results with respect to allocation rationales and the data collection period.The results within one impact category vary strongly among metals (up to four orders of magnitude for copper compared to rhodium). Moving from mass- to value-based allocation changes the result for a given metal by up to two orders of magnitude. If value-based allocation is used, the selected reference year for metals prices influences the results by up to a factor of two.Allocation rationales are critically analyzed, and it is shown that none reflect the business model or other system drivers. While the model is focused on quantifying environmental impacts of metal outputs, the actual process is economically driven to efficiently treat a continuously changing feed mix. The complexity of a smelter-refinery cannot be captured by static, attributional inventory models, which is why the choice of allocation rationale remains arbitrary. Instead, marginal, parameterized models are needed; however, such models are substantially more time and data intensive and require disclosure of more detailed, process specific data.  相似文献   

13.
According to existing estimates, available old copper scrap has more than tripled over the past 40 years. Secondary production (that is, copper produced from recycling old scrap), however, has only doubled. Indeed, over the past 10 years, while copper consumption and primary production have continued to expand briskly, while available old scrap has increased by over 35%, secondary production has actually stagnated.For a world concerned with sustainable development and the quality of the earth's environment, this performance is disappointing and in need of explanation. Other things being equal, one would expect the amount of recycling to increase with the availability of scrap, as many econometric models of the world copper market developed over the past several decades explicitly assume.The key to understanding sluggish growth in secondary production, this paper argues, is distinguishing carefully between (1) the flow of old scrap that arrives each year from products reaching the end of their useful lives during the year and (2) the available stock of old scrap that was not recycled during earlier years presumably because it was too costly to do so. Using an econometric model, the paper shows that old scrap stocks, which have contributed most of the increase in available old copper scrap over the years, have a very modest impact on secondary production. Old scrap flows have a much greater effect, but they account for only about 4% of the available old scrap for any given year.  相似文献   

14.
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.  相似文献   

15.
This study examines the effects of municipal promotion and education (P&E) investments on the recycling rates of recyclables found in Ontario's residential waste stream. Using panel data collected from 223 Ontario municipalities between 2003 and 2012, this study examines whether investments in recycling P&E lead to an increase in household recycling. Investments in recycling promotion and education have been characterized as a policy best practice and is promoted as one of the primary drivers of resource conservation and sustainability in Ontario. Focus is placed on analyzing: (a) the relationship between P&E expenditures and recycling rates in the province, (b) the relationship between municipal recycling rates and P&E investments at different funding levels and (c) the impact of locality on promotion and education efficacy. The results of the statistical regressions indicate that investments in recycling P&E do not increase municipal recycling rates, necessitating a re-evaluation of existing policy and management practices.  相似文献   

16.
The USA is becoming increasingly dependent on key strategic metals (such as chrome, cobalt, manganese and platinum-group metals) from politically unstable regions of the world. This dependence is the result of an inconsistent and fragmented US non-fuel minerals policy. Neglect of the US minerals industry has led to a decline in US mineral production and processing capabilities. Options for a comprehensive US non-fuel minerals policy include increased domestic production; increased substitution and recycling; a domestic stockpiling programme; and diversification of, and ensured access to, foreign sources of supply. These four options are examined and recommendations are made for increased mineral surveys of public lands, a regulatory review, domestic production of strategic minerals, tax incentives, conservation, stockpiling, and a foreign policy that will ensure security of supply.  相似文献   

17.
Recycling across Ireland has increased incrementally since the introduction and implementation of the Landfill Directive 1999/31/EC, the WEEE directive 2002/96/EC, and the Waste Framework Directive 2008/98/EC. As a result of the implementation of the aforementioned directives, the volume of waste sent to landfill has fallen, household composting increased and recovery of municipal waste recyclables continues to improve. The improvements witnessed, are in part achieved as a result of the introduction of the 2-bin and 3-bin collection service. The improvement of facilities at recycling centres and bring banks have been instrumental in the gains achieved in recycling rates.NIMBYism, however, remains a constant impediment to procuring suitable sites for the recycling receptacles. It is not unusual for people to seek convenience whilst not wanting the associated problems on their doorstep. NIMBYism is something that most individuals are guilty of and it is considered to be quite normal. The structural difficulties associated with recycling rates are the first that need to be confronted. By altering the landscape, behaviours can be changed and improved. In the instance of bring banks and the social problems that are associated with them such as fly-tipping, changing the visual aspect of the receptacles and their positioning may improve recycling rates and reduce the number of instances of fly-tipping and littering.This paper presents the results of 509 questionnaires distributed to nine schools in the Limerick City and County environs. The questionnaires, distributed to primary schools actively participating in the Green School Programme, were analysed so as to get an understanding of the motivations and the deterrents surrounding household recycling of waste. From the analysis recommendations are made to reduce the social problems associated with bring banks and to increase the percentage of householders availing of waste collection services.  相似文献   

18.
With the number of vehicles expected to increase to 1.85 billion by 2030 and the scrap generated from end-of-life vehicles (ELVs) expected to be 3.71 billion tonnes, there is a strong motivation to properly process the flow of these materials. The EU Directive on end-of-life vehicles (EU ELV Directive) aims to increase recovery and recycling rates of ELVs in order to reduce waste and improve environmental performances. Long-term optimization planning of vehicle recycling is increasingly important. However, there is a lack of research of uncertainties in the vehicle recycling system, none of the previous studies analyzed the linkage and trade-offs between decision risk and system performances, and no previous research was reported on interval-based programming for vehicle recycling planning problem. In order to meet the imposed eco-efficiency quotas, maximize system profit and minimize decision risk, and at the same time fill the identified research gaps, a risk explicit interval linear programming model for optimal long-term planning in the EU vehicle recycling factories was developed. It can create optimal plans for procuring vehicle hulks, sorting of generated material fractions, allocation of sorted waste flows and allocation of sorted metals for desired value of the system aspiration level. A numerical study demonstrated the potentials and applicability of the proposed model. Vehicle recycling factories aim at reaching the highest possible level of quantity and quality of sorted metal flows. The future eco-efficiency quotas will not endanger their business. The success of the final phase of implementation of the EU ELV Directive is not jeopardized, because even the future eco-efficiency quotas were reached in all created test problems. Quantity of land-filled wastes will be radically reduced after January 1, 2015. The model results and trade-offs would be valuable for supporting the EU vehicle recycling factories in creating optimal long-term production strategies and reducing the risk for uncertain situations.  相似文献   

19.
Municipal waste arisings continued to increase during the 1970s in all the industrialized economies. Currently, in the midst of a severe international economic recession, the continuing escalation in the costs of waste disposal poses significant problems for municipal authorities. With the data constraints firmly in mind, this paper estimates the secondary materials supply potential of the municipal waste stream. The calculations suggest that a significant supply potential remains to be utilized despite ‘respectable’ overall recycling rates in most industrial economies. Resource recovery options can be divided into ‘low technology’ source separation schemes and ‘high technology’ mechanical separation schemes. The authors concentrate on the former option and appraise (on the basis of social cost-benefit analysis) a number of schemes that have operated in both Europe and North America.  相似文献   

20.
With the annual increase in waste generation and heavy reliance on landfilling as disposal, method in Malaysia, it is just a matter of time before significant problems of space limitations, health, and environmental issues hit the nation severely. This paper attempts to develop an overview on solid, waste recycling in Malaysia at the most basic level of a community or nation which is the household, unit. Households are the main primary source of municipal solid waste in Malaysia, consisting of, recyclable materials at most 70% to 80% of the total waste composition as found placed in the, landfills. Overview on the existing household solid waste recycling policy and program status in, Malaysia is relevant in enhancing solid waste management measure from recycling perspective. Despite the high potential and opportunities for solid waste recycling, wastes are still simply being, dumped in an open area of ground without any attempt for recovery and recycling. Comparing to, recycling rates of neighboring countries, Malaysia is falling back at merely 5% which proves how, uncommon recycling practice is. The government is committed to significantly improve the national's, solid waste management services especially in waste minimization. Fortunately the emphasis on, recycling as a sustainable waste management strategy has taken a shift in paradigm as wastes, separation and recycling are part of the major changes in the current policy implementation. With, issues and challenges in recycling practice that were highlighted in this context especially from the, aspects of information availability and other loopholes within solid waste management policies and, related recycling program within the community, the question on whether the goals in 2020 can be, met remains unsure of but there is a possibility for a successful implementation of sustainable solid, waste management particularly in recycling.  相似文献   

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