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1.
The significance of technical data, as well as the significance of system boundary choices, when modelling the environmental impact from recycling and incineration of waste paper has been studied by a life cycle assessment focusing on global warming potentials. The consequence of choosing a specific set of data for the reprocessing technology, the virgin paper manufacturing technology and the incineration technology, as well as the importance of the recycling rate was studied. Furthermore, the system was expanded to include forestry and to include fossil fuel energy substitution from saved biomass, in order to study the importance of the system boundary choices. For recycling, the choice of virgin paper manufacturing data is most important, but the results show that also the impacts from the reprocessing technologies fluctuate greatly. For the overall results the choice of the technology data is of importance when comparing recycling including virgin paper substitution with incineration including energy substitution. Combining an environmentally high or low performing recycling technology with an environmentally high or low performing incineration technology can give quite different results. The modelling showed that recycling of paper, from a life cycle point of view, is environmentally equal or better than incineration with energy recovery only when the recycling technology is at a high environmental performance level. However, the modelling also showed that expanding the system to include substitution of fossil fuel energy by production of energy from the saved biomass associated with recycling will give a completely different result. In this case recycling is always more beneficial than incineration, thus increased recycling is desirable. Expanding the system to include forestry was shown to have a minor effect on the results. As assessments are often performed with a set choice of data and a set recycling rate, it is questionable how useful the results from this kind of LCA are for a policy maker. The high significance of the system boundary choices stresses the importance of scientific discussion on how to best address system analysis of recycling, for paper and other recyclable materials.  相似文献   

2.
The significance of technical data, as well as the significance of system boundary choices, when modelling the environmental impact from recycling and incineration of waste paper has been studied by a life cycle assessment focusing on global warming potentials. The consequence of choosing a specific set of data for the reprocessing technology, the virgin paper manufacturing technology and the incineration technology, as well as the importance of the recycling rate was studied. Furthermore, the system was expanded to include forestry and to include fossil fuel energy substitution from saved biomass, in order to study the importance of the system boundary choices. For recycling, the choice of virgin paper manufacturing data is most important, but the results show that also the impacts from the reprocessing technologies fluctuate greatly. For the overall results the choice of the technology data is of importance when comparing recycling including virgin paper substitution with incineration including energy substitution. Combining an environmentally high or low performing recycling technology with an environmentally high or low performing incineration technology can give quite different results. The modelling showed that recycling of paper, from a life cycle point of view, is environmentally equal or better than incineration with energy recovery only when the recycling technology is at a high environmental performance level. However, the modelling also showed that expanding the system to include substitution of fossil fuel energy by production of energy from the saved biomass associated with recycling will give a completely different result. In this case recycling is always more beneficial than incineration, thus increased recycling is desirable. Expanding the system to include forestry was shown to have a minor effect on the results. As assessments are often performed with a set choice of data and a set recycling rate, it is questionable how useful the results from this kind of LCA are for a policy maker. The high significance of the system boundary choices stresses the importance of scientific discussion on how to best address system analysis of recycling, for paper and other recyclable materials.  相似文献   

3.
The amount of household refuse has steadily increased in Sweden. Strategies for household waste reduction include sorting, recycling, re-use and repair. Two categories of motivational factors determine disposal behaviour, external and internal. The external factors include administrative, economic, information and physical measures. The internal factors include knowledge, values and attitudes of individuals. Environmentally friendly disposal behaviour is best achieved when both external and internal motivational factors argue for performing activities benign to the environment. The data were collected by interviewing households and stakeholders in a metropolitan area and by studying the facilities for recycling and re-use there. The results show that over 80% of the inhabitants sorted most paper and glass; they were satisfied with the facilities and considered the behaviour important for the environment. The external motivational factors for this behaviour were very strong, with numerous bins and ample information. National policy, formulated in the eco-cycle bill with specified achievement levels, local responsibilities for organising waste management, supporting citizens with physical facilities, information and moti vational arguments, seems to be a successful combination when implementing environmental policy in this sector.  相似文献   

4.
Life cycle assessment (LCA) can be successfully applied to municipal solid waste (MSW) management systems to identify the overall environmental burdens and to assess the potential environmental impacts. In this study, two methods used for current MSW management in Phuket, a province of Thailand, landfilling (without energy recovery) and incineration (with energy recovery), are compared from both energy consumption and greenhouse gas emission points of view. The comparisons are based on a direct activity consideration and also a life cycle perspective. In both cases as well as for both parameters considered, incineration was found to be superior to landfilling. However, the performance of incineration was much better when a life cycle perspective was used. Also, landfilling reversed to be superior to incineration when methane recovery and electricity production were introduced. This study reveals that a complete picture of the environmental performance of MSW management systems is provided by using a life cycle perspective.  相似文献   

5.
Future limitations on the availability of selected resources stress the need for increased material efficiency. In addition, in a climate-constrained world the impact of resource use on greenhouse gas emissions should be minimized. Waste management is key to achieve sustainable resource management. Ways to use resources more efficiently include prevention of waste, reuse of products and materials, and recycling of materials, while incineration and anaerobic digestion may recover part of the embodied energy of materials. This study used iWaste, a simulation model, to investigate the extent to which savings in energy consumption and CO2 emissions can be achieved in the Netherlands through recycling of waste streams versus waste incineration, and to assess the extent to which this potential is reflected in the LAP2 (currently initiated policy). Three waste streams (i.e. household waste, bulky household waste, and construction and demolition waste) and three scenarios compare current policy to scenarios that focus on high-quality recycling (Recycling+) or incineration with increased efficiency (Incineration+). The results show that aiming for more and high-quality recycling can result in emission reductions of 2.3 MtCO2 annually in the Netherlands compared to the reference situation in 2008. The main contributors to this reduction potential are found in optimizing the recycling of plastics (PET, PE and PP), textiles, paper, and organic waste. A scenario assuming a higher energy conversion efficiency of the incinerator treating the residual waste stream, achieves an emission reduction equivalent to only one third (0.7 MtCO2/year) of the reduction achieved in the Recycling+ scenario. Furthermore, the results of the study show that currently initiated policy only partially realizes the full potential identified. A focus on highest quality use of recovered materials is essential to realize the full potential energy and CO2 emission reduction identified for the Netherlands. Detailed economic and technical analyses of high quality recycling are recommended to further evaluate viable integrated waste management policies.  相似文献   

6.
由于社会和经济因素的要求,当今的建筑生命周期要最大程度地完成圆形的循环过程,即重新使用拆建物料制造新产品。循环经济的大背景下,承建商通过坚实的理论基础,采用分层次的方法来进行建筑废弃物的管理。文中总结了两种方法的优点和缺点,进行了混合回收与源头分离两种方法的比较研究。最值得注意的是两个不同的意向方案:绿色星球计划和ICC-ESSAVETM方案。突出的可持续认证和设计方案及绿色星球计划侧重的能源效率模型时常被繁重调试系统的LEED所青睐。一旦被国际编码理事会所批准,这些文件可以在LEED的评分系统下或绿色星球计划中,帮助其寻找资格评分。文章最后分析了建筑废弃物的回收流程,并得出结论:高达95%的建筑和拆迁建筑废弃物都可以回收;回收相比垃圾填埋更节省资金;源头分离较混合回收需要更多的管理和劳动力,但能获得更大的经济利益;承建商应该组织和管理现场的回收工作。  相似文献   

7.
In policy support of municipal solid waste (MSW) management, life cycle assessment (LCA) can serve to compare the environmental or economic impacts of two or more options for waste processing. The scope of waste management LCAs generally focuses less attention on future developments, e.g., where will recycling take place, and more on the environmental performance of prototypes, e.g., the incineration of all waste compared to recycling. To provide more robust support for Swiss waste glass-packaging disposal, scenarios of Swiss waste glass-packaging are assessed from a life cycle perspective. The scenarios consist in schemes for the disposal of the total amount of Swiss waste glass-packaging, i.e., different combinations of recycling and downcycling in Switzerland or abroad developed in Part I, Meylan et al. (2013). In this article (Part II), the disposal schemes are assessed with respect to eco-efficiency, an indicator that combines total environmental impacts and gross value added in Switzerland. Results show that no policy alternative guarantees environmental impact reductions and gross value added gains under all developments of exogenous constraints. Downcycling to foam glass in Switzerland is not only an environmentally sound disposal option, but it also buffers gross value added losses in case domestic recycling (and thus glass-packaging production in Switzerland) ceases in the future. The substitution of products based on raw materials other than Swiss cullet is the main responsible for change in environmental and economic impacts. Hence, an eco-efficiency maximizing policy should consider the products of disposal schemes. The combination of scenario analysis and eco-efficiency assessment as presented in this paper can be applied to other contexts (i.e., countries, waste fractions).  相似文献   

8.
Discussions of municipal solid waste (MSW) management are influenced increasingly by the concept of the waste hierarchy which, broadly speaking, places landfill as the least acceptable option for dealing with MSW, followed by incineration, recycling, re-use and reduction at source. In this paper, we want to question the wisdom of applying the waste hierarchy in a region with a low population density. The hierarchy was first developed with reference to the high population density areas such as the core of the EU. However, in low population density areas the economics of the various approaches to MSW is likely to be quite different. As a result, the application of the hierarchy could place an undue economic burden on a region relative to the environmental benefits that might arise. We estimate the costs, both internal and external, of the various methods of dealing with MSW in an area with the appropriate population density, drawing on information from a wide variety of sources. We find that landfill is significantly cheaper than in high population density areas, even when account is taken of the associated externalities. In addition, it is generally cheaper than the alternative methods. As such, we conclude that landfill should not be shunned as a disposal method in low population density areas.  相似文献   

9.
Material efficiency: A white paper   总被引:1,自引:0,他引:1  
For most materials used to provide buildings, infrastructure, equipment and products, global stocks are still sufficient to meet anticipated demand, but the environmental impacts of materials production and processing, particularly those related to energy, are rapidly becoming critical. These impacts can be ameliorated to some extent by the ongoing pursuit of efficiencies within existing processes, but demand is anticipated to double in the next 40 years, and this will lead to an unacceptable increase in overall impacts unless the total requirement for material production and processing is reduced. This is the goal of material efficiency, and this paper aims to stimulate interest in the area. Four major strategies for reducing material demand through material efficiency are discussed: longer-lasting products; modularisation and remanufacturing; component re-use; designing products with less material. In industrialised nations, these strategies have had little attention, because of economic, regulatory and social barriers, which are each examined. However, evidence from waste management and the pursuit of energy efficiency suggests that these barriers might be overcome, and an outline of potential mechanisms for change is given. In bringing together insights into material efficiency from a wide range of disciplines, the paper presents a set of 20 open questions for future work.  相似文献   

10.
Recent targets for reduced amounts of waste to landfills in Sweden will result in a large increase in waste incineration with recovery of energy, used primarily for district heating. The aim of this study is to investigate what changes in the usage of other fuels and technologies for district heat production would be caused by this increase. A questionnaire was sent out to the largest district heating companies, and simulations in an energy systems model were carried out. The analysis shows that increased waste incineration reduces the demand for other fuels, especially biomass, for district heat production. The effects include reductions in operating hours as well as the avoidance or postponement of investments in new plants for district heat production. Increased waste incineration will also lead to a greater use of district heating in Sweden.  相似文献   

11.
A model is presented for evaluating waste management systems for their contribution to a sustainable development, including environmental, economic and social aspects. The model was tested in a case-study, where groups of long-term unemployed people were offered both education on environmental issues and practical work with the recovery and recycling of building and demolition waste as a form of vocational development. Application of the suggested model revealed the overall effects on sustainability of different methods of waste management. In addition, negative aspects of the systems analysed were identified, which led to discussions about possible improved practices within the waste management systems. Two of the waste management systems investigated (the recycling of steel and re-use of sanitary porcelain) showed a potential contribution to sustainable development in all of the aspects studied. Preparing bricks for re-use showed the largest potential for eco-efficiency, but had negative effects on sustainability from the social perspective of health and the working environment. The possibility of further use of the model and the remaining obstacles to such analyses are discussed. One observation is that the data collection needed to perform this kind of sustainability analysis is resource-demanding, and that it would therefore be better to identify a smaller number of key indicators.  相似文献   

12.
To be rightly implemented, an environmental policy ought to set an institutional framework (goals, rules and instruments) which incents decentralised actors to adopt the appropriate range of technologies. In the household waste management policy, the development of valorisation techniques (and particularly recycling) must be supported by convenient instruments and incentives. The paper analyses the problems encountered with the French household waste policy to ensure the takeoff of recycling techniques. At the moment, a rather under-proportioned institutional setting leads to favour the adoption of incineration with energy recovery at the expenses of recycling. This tends to create a structural bias in favour of incineration.  相似文献   

13.
The Packaging and Packaging Waste Directive has had an undeniable impact on waste management throughout the European Union. Whereas recycling and recovery targets are the same, member states still enjoy a considerable degree of freedom with respect to the practical organization and management strategies adopted. Nevertheless, in all cases, the industry (which brings packaging material onto the market) should be responsible for the costs associated with packaging waste recycling/recovery (following the extended producer responsibility principle). The current paper compares and contrasts the institutional frameworks and financial costs and benefits of waste management operators for Belgium and Portugal. The unit costs of selective collection and sorting of packaging waste are provided for both countries. In Belgium, the costs of recycling seem to be fully supported by the industry (through Fost Plus, the national Green Dot agency). In Portugal the fairness of the recycling system depends on the perspective adopted (economic or strictly financial). Adopting a strictly financial perspective, it seems that Sociedade Ponto Verde (SPV, the Portuguese Green Dot agency) should increase the transfers to local authorities. However, the conclusions differ for this country if the avoided costs with refuse collection and other treatment are taken into account.  相似文献   

14.
In 1992, Sweden introduced a producer responsibility ordinance which explicitly states that sorted out, collected waste paper must be material recycled. Another alternative could be to recover energy by incineration. Material recycling was prioritized, although there is no environmental consensus favouring either of the alternatives. By calculating shadow prices of waste paper for the paper industry and for the heating plants, this study tries to determine whether waste paper should be partly incinerated. The study also addresses whether the producer responsibility has contributed to an inefficient allocation of waste paper. The results find no economic support for the producer responsibility.  相似文献   

15.
成都市市区固体生活垃圾现状分析和对策初探   总被引:4,自引:0,他引:4  
本文介绍了成都市生活垃圾的现状与对策,包括近几年生活垃圾的产生量、组成和热值。根据生活垃圾的组成和热值,认为处理垃圾要逐步达到堆肥而实现资源化为主,适当发展焚烧发电处理,尽量减少填埋处理。  相似文献   

16.
Recovery, reuse and recycling of industrial residuals, often dismissed as wastes, are common in India and other industrializing countries largely due to lower associated costs. Some wastes are reused within the facility where they are generated, others are reused directly by nearby industrial facilities, and some are recycled via the formal and informal recycling markets. Direct inter-firm reuse is the cornerstone of the phenomenon termed industrial symbiosis, where firms cooperate in the exchange of material and energy resources. This study applies material flow analysis to an economically diverse industrial area in South India to characterize the recovery, reuse and recycling of industrial residuals. It quantifies the generation of waste materials from 42 companies as well as the materials that are directly traded across facilities and those that are recycled or disposed. This study encompasses a business cluster in Mysore in the State of Karnataka, and is the first in India to thoroughly quantify material flows to identify existing symbiotic connections in an industrial area. Examined industries in this industrial area generate 897,210 metric tons of waste residuals annually, and recovered 99.5% of these, 81% with reused by the companies that generated them, with one company, a sugar refinery, processing most of this amount. Geographic data show that operations within 20 km of the industrial area receive over 90% of residuals exiting facility gates. Two-thirds of this amount goes directly to other economic actors for reuse. This study makes key contributions to the literature in distinguishing how particular types of materials are reused in different ways, the geographic extent of symbiotic activities and the important role of the informal sector in industrial waste management in industrializing regions.  相似文献   

17.
This article presents a comparative analysis of the performance in formal and informal areas that deal with solid waste in Brazil. The article demonstrates that there has been significant progress in areas related to recycling and that this progress has been based mainly on informality and on the precarious labour conditions for the pickers of recyclable materials. The article also focuses on the problems found in the model for waste recovery that is being implemented in Brazil and that is based on allocation of precarious waste recovery facilities; this model has mostly small operational capabilities even in large municipalities. These problems are discussed in contrast to the great challenges imposed by the new legal framework of the country. Finally, the article proposes a categorisation of the technological models of material recovery facilities (MRFs) based on their degree of automation and nominal capacities in a manner similar to that used worldwide for incineration plants.  相似文献   

18.
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   

19.
H作业区经过对节能减排中问题的总结,实施了哈得四联合站放空气回收轻烃外输、哈得一联合站二段气回收、污水闭路循环回收利用、淡化水流程优化等节能减排工程,促进了节能减排,减少了碳排放,实现了清洁生产,取得了较好的经济效益和环境效益。  相似文献   

20.
Changes in the trends in the material composition of domestic and imported automobiles and the increasing cost of landfilling the non-recyclable portion of automobiles (automobile shredder residue or ASR) pose questions about the future of automobile recycling in the United States. In response to these challenges, new and innovative approaches to automobile recycling are being developed. This paper presents the findings of a recent study to examine the impacts of these changes on the life cycle energy consumption of automobiles and on the quantity of waste that must be disposed of. Given the recycle status quo, trends in material composition and the viability of recycling the non-metallic components of the typical automobile are of secondary importance when compared to the energy consumed during the life of the automobile. The energy savings resulting from small changes in the fuel efficiency of a vehicle overshadow potential energy losses associated with the adoption of new and possibly non-recyclable materials. Under status quo conditions, the life cycle energy consumed by the typical automobile is projected to decrease from 599 million Btus in 1992 to 565 million Btus in 2000. Energy consumed during the manufacture of the typical car will increase from about 120 to 140 million Btus between 1992 and 2000, while energy used during vehicle operation will decrease from 520 to 480 million Btus. This study projects that energy saved at the recycle step will increase from 41 million Btus in 1992 to 55 million Btus in 2000. This study also investigated the energy impacts of several potential changes to the recycle status quo, including the adoption of technologies to retrieve the heat value of ASR by incineration and the recycle of some or all thermoplastics in the typical automobile. The study estimates that under optimistic conditions —i.e., the recycling of all thermoplastics and the incineration with heat recovery of all remaining ASR —about 8 million Btus could be saved per automobile —i.e., an increase from about 55 to 63 million Btus. In the more realistic scenario —i.e., the recycling of easy-to-remove thermoplastic components (bumper covers and dash-boards) —the potential energy savings are about 1 million Btus per vehicle. It is estimated that the annual quantity of ASR in the United States could be reduced from about 5 billion pounds to as little as 1 billion pounds of ash if all ASR is incinerated. Alternatively, ASR quantity could be reduced to about 4 billion pounds if all thermoplastics in automobiles are recycled. However, in the case of recycling only thermoplastic bumper covers and dashboards, the quantity of ASR would be reduced by only 0.2 billion pounds. A significant reduction or increase in the size of the ASR waste stream will not in itself have a large impact on the solid waste stream in the United States.  相似文献   

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