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1.
Recycling policy, insofar as it exists, tends to be heavily weighted towards price manipulation. However, it is by now fairly well established that the supply of secondary materials is in most cases quite unresponsive to price changes, so that price-based policies are very unlikely to be effective. This view is further borne out by an attempt to consider explicitly the sort of adjustment processes which must necessarily occur in the generally volatile markets for waste materials. It is suggested that price-oriented policies must first influence the expectations of potential suppliers before any response is forthcoming When this is considered along with the evidently small reaction to those expectations, an even more pessimistic conclusion about the suitability of standard measures to encourage recycling is reached.  相似文献   

2.
Various wastes and by-product materials are generated in the Sultanate of Oman including reclaimed asphalt pavement (RAP) aggregate, demolition concrete, cement by-pass dust (CBPD), copper slag, petroleum-contaminated soils (PCS), discarded tires, incinerator ash, and others. Recycling of such materials in construction is not practiced. Research data are also minimal into the potential use of selected materials in construction applications. This paper will present the results of several laboratory studies conducted into the use of PCS in asphalt concrete mixtures; on the use of CBPD in soil stabilization and flowable fill mixtures; on the utilization of copper slag and CBPD as cementitious materials; on the use of incinerator ash in cement mortars; and on the use of RAP aggregate in road bases and sub-bases. Laboratory data generally indicate that it is feasible to partially reuse some of these materials in construction provided that economic incentives and environmental concerns are taken into consideration.  相似文献   

3.
This study evaluated, both qualitatively and quantitatively, waste materials from several major Quebec grocery stores. Averaged over nine sampling dates, cardboard, paper and wood products represented 43 and 74% of waste material, based on weight and volume, respectively while organic matter including fruits, vegetables, baked goods and meat products represented 40 and 10% of waste material based on weight and volume. Plastics, wrapping and bagging materials, represented over 7 and 13% of waste material based on weight and volume, respectively, and other recyclable waste materials such as glass, metal and various miscellaneous objects, represented 4 and 2% of waste material based on weight and volume. On average, 60.6 kg waste/employee per week was generated by the three stores. Store size was not a determining factor in the composition of grocery store waste material. These results suggest that costs associated with supermarket waste disposal may be substantially reduced by source-separation of recyclable and compostable materials while reducing pressure for incineration or landfill. Therefore, the adoption of recycling and source-separation programs, and studies to determine problems and costs associated with the implementation of such programs are recommended.  相似文献   

4.
States differ in the components or solid waste management activities which they include when determining solid waste reduction and recycling rates. Thus, when attempting to draw comparisons among states, confusion arises in two ways: (1) use of two types of rates; and (2) use of different components or activities when calculating a given rate. This paper presents a mathematical basis for understanding the impacts on rate calculations when variations occur in the components and activities included in those calculations. Estimates of the incremental changes occurring in the rate calculations when incineration or selected components such as yard waste, construction and demolition wastes, and junked automobiles, are added to a base of municipal solid waste constituents are found using national data. Finally, the achieved rates reported by states counting different combinations are compared.  相似文献   

5.
合理利用境外的可用作原料的固体废物,可以弥补我国国内资源的相对不足,但固体废物固有的废物属性仍不可避免地会带来一定的环境负面影响。建立可用作原料的固体废物进口可行性评价体系,对于在合理利用境外废物资源的同时,保护和改善环境具有重要意义。本文论述了我国建立可用作原料的固体废物进口可行性评价体系的理论和原则,并根据影响可用作原料的固体废物进口可行性评价的因素分析,构建了可用作原料的固体废物进口可行性评价指标体系框架。  相似文献   

6.
7.
The aim of this study was to evaluate the possible toxicity of the leachate produced by the residues generated in the process of recycling lead from waste batteries. These residues are slag, which once formed, is characterised by its content in ferrous sulphide, sodium carbonate as well as residual coke from the process. It also contains, as minor components, lead and other heavy metals. The slag was stored and watered periodically over a period of 6 months, its composition changing until finally becoming inert, with no exothermal activity. The slag was leached, and its ecotoxicity was determined by means of the bioluminescence test, along with its content in heavy metals. The results obtained indicate a greater degree of toxicity in the residues with a shorter storage period than the established one, and which were therefore still in the phase of decomposition. However, in the samples taken on completing 6 months of storage, the EC50 value of the leachate was found to be higher than 3000 mg/l. Hence, a storage period under suitable environmental conditions which leads to inactivity of the residue as well as a decrease in its ecotoxicity, is considered absolutely essential. At the same time, a direct relationship was observed between the lead content and the ecotoxicity value.  相似文献   

8.
Increasing levels of household waste have raced up national, regional and municipal environmental policy agendas around the world, especially as heavy reliance on landfill and incineration is becoming prohibitively expensive and also a high profile source of local voter dissent or vociferous NIMBY behaviour. In an attempt to reduce reliance on these options, UK local authorities have increasingly been forced to turn to recycling. This paper reports on a broad empirical study of household recycling, utilizing national survey-based evidence (drawn from over 31 000 interviews in Scotland). Hitherto, very few published empirical studies have addressed the household recycling decision using national survey data to furnish baseline evidence. For this purpose logit analysis is undertaken, using data extracted from the Scottish Household Surveys of 2000 and 2001. This work also serves as the basis for further detailed modelling of a selection of illustrative household types. After consideration of particular waste streams and the availability of different recycling schemes, the effects on the probability of recycling participation of age, income level, household composition, car ownership and local authority were analysed. While there are clear income effects, the picture regarding the impact of household composition and some other factors is more complex.  相似文献   

9.
The author describes a futures study which looked at the long term supply of raw materials and resources for Sweden. The study involves the construction of a number of possible scenarios of Swedish and world development and an examination of their implications for resource supply. The conclusion is that there are unlikely to be any physical limits to growth over the next 25 years or so but that there may well be political obstacles. In any event, ideas of development are largely conditioned by historical and social circumstances and new paradigms may well produce new models of development.  相似文献   

10.
This Special Issue provides several different perspectives on the complex issue of packaging waste recycling. It comprises a diverse and rich set of contributions with insights from very different disciplines that range from economics to engineering. All types of “costs and benefits” are addressed in this collection of articles. In addition to the economic and strictly financial impacts of selective collection and sorting of packaging waste, several authors discuss other types of impacts, such as the environmental and social ones. The reader will find articles that address recycling systems as a whole, pieces that focus on specific impacts and detailed discussions of particular material streams or waste management strategies. The Special Issue represents an indispensable resource for academics, policy-makers and practitioners with interests in recycling and packaging waste management.  相似文献   

11.
Municipal solid waste (MSW) contains materials which could be put to good use, yet it continues to be discarded, which suggests that it contains little or nothing of value under current conditions. This paper discusses the technical reasons for the lack of commercial interest in recovering materials from MSW. After examining the nature of the salvage industry and trends in the use of materials, the paper considers the characteristics of secondary materials, the properties required of them, and the scope for increased salvage activity. The market prospects are described for waste paper, ferrous and non- ferrous scrap, glass and polymers.  相似文献   

12.
The availability and security of raw materials supply have taken on a new political dimension within the last few years. These issues influence the economic and political rank of nations, affecting their independence, their standards of living and the competitive position of their industries. The importance of raw materials supply will continue to grow, for both the developed industrial and the developing countries. The European Community depends on external sources for 50–100% of most of its raw materials. Although the degree of dependence varies considerably from commodity to commodity, sources are not diversified enough to guarantee supply. Yet 1700–2000 million tons of waste are generated annually in the Community, containing substances of potential value—including metals, glass, rubber, textiles, oil, plastics—of which 70– 80% are tipped. This represents a loss of materials as far as they could be reused economically. This article argues that efforts should be made to recover and reuse the maximum possible of these resources to reduce the Community's dependence on, and improve its security of, raw materials supplies, and to lower the balance of payments burden.  相似文献   

13.
Many projects have attempted to model the consumption and recycling patterns of important raw materials, but without assessing the significance of that raw material to the UK. This article methodically assesses all the factors which influence the importance of each raw material, and ranks them in descending order of importance. Sensitivity analyses confirm that the resultant ranking is largely independent of factors used. Copper, oil, iron and steel, and aluminium, are the four most significant materials. This work provided the justification for a detailed examination of the copper industry and, in particular, the significance of recycling.  相似文献   

14.
The authors summarize the results of an International Symposium by Correspondence on the use of waste and by-product materials in the construction industry which was recently organized by the Building Research Establishment (BRE) on behalf of the Réunion Internationale des Laboratoires d'Essais et de Recherches sur les Matériaux et les Constructions (RILEM). Information on the production and use of the more important wastes is tabulated and the main findings and national trends are discussed.  相似文献   

15.
This paper discusses a significant illicit economy, including black and grey aspects, associated with medical waste scavenging and recycling in a megacity, considering hazards to the specific group involved in scavenging as well as hazards to the general population of city dwellers. Data were collected in Dhaka, Bangladesh, using a variety of techniques based on formal representative sampling for fixed populations (such as recycling operatives) and adaptive sampling for roaming populations (such as scavengers). Extremely hazardous items (including date expired medicines, used syringes, knives, blades and saline bags) were scavenged, repackaged and resold to the community. Some HCE employees were also observed to sell hazardous items directly to scavengers, and both employees and scavengers were observed to supply contaminated items to an informal plastics recycling industry. This trade was made possible by the absence of segregation, secure storage and proper disposal of medical waste. Corruption, a lack of accountability and individual responsibility were also found to be contributors. In most cases the individuals involved with these activities did not understand the risks. Although motivation was often for personal gain or in support of substance abuse, participants sometimes felt that they were providing a useful service to the community.  相似文献   

16.
Phosphate rocks, used for phosphorus (P) fertilizer production, are a non-renewable resource at the human time scale. Their depletion at the global scale may threaten global food and feed security. To prevent this depletion, improved P resource recycling from food chain waste to agricultural soils and to the food and feed industry is often presented as a serious option. However, waste streams are often complex and their recycling efficiency is poorly characterized. The aim of this paper is to estimate the P recovery and recycling potential from waste, considering France as a case study. We assessed the P flows in food processing waste, household wastewater and municipal waste at the country scale using a substance flow analysis for the year 2006. We also quantified the P recycling efficiency as the fraction of P in waste that ultimately reached agricultural soils or was recycled in the food and feed industry. Efforts were made to limit data uncertainty by cross-checking multiple data sources concerning P content in waste materials. Results showed that, in general, P recovery in waste was high but that the overall P recycling efficiency was only 51% at the country scale. In particular, P recycling efficiency was 75% for industrial waste, 43% for household wastewater and 47% for municipal waste. The remaining P was discharged into water bodies or landfilled, causing P-induced environmental problems as well as losses of nutrient resources. Major P losses were through food waste (which amounted to 39% of P in available food) and treated wastewater, and the findings were confirmed through cross-checking with alternative data sources. Options for improving P resource recycling and, thereby, reducing P fertilizer use were quantified but appeared to be less promising than scenarios based on reduced food waste or redesigned agricultural systems.  相似文献   

17.
In Korea due to rapid economical growth followed by urbanisation, breakage of large traditional families into small nuclear families, continuous changes in equipment features and capabilities causes tremendous increase in sale of new electrical and electronic equipment (EEE) and decrease in sale of used EEE. Subsequently, the ever-increasing quantity of waste electrical and electronic equipment (WEEE) has become a serious social problem and threat to the environment. Therefore, the gradual increase in the generation of WEEE intensifies the interest for recycling to conserve the resources and protect the environment. In view of the above, a review has been made related to the present status of the recycling of waste electrical and electronic equipment in Korea. This paper describes the present status of generation and recycling of waste electrical and electronic equipment, namely TVs, refrigerators, washing machines, air conditioners, personal computers and mobile phones in Korea. The commercial processes and the status of developing new technologies for the recycling of metallic values from waste printed circuit boards (PCBs) is also described briefly. Since 1998, three recycling centers are in full operation to recycle WEEE such as refrigerators, washing machines and air conditioners, having the total capacity of 880,000 units/year. All waste TVs are recently recycled on commission basis by several private recycling plants. The recycling of waste personal computers and mobile phones is insignificant in comparison with the amount of estimated obsolete those. Korea has adopted and enforced the extended producer responsibility (EPR) system. Korea is making consistent efforts to improve the recycling rate to the standards indicated in the EU directives for WEEE. Especially environmentally friendly and energy-saving technologies are being developed to recycle metal values from PCBs of WEEE.  相似文献   

18.
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   

19.
This paper analyzes the effect of price uncertainty and irreversible investment on the decision of municipalities to switch from landfill waste disposal to recycling by developing a model to predict recycling adoption behavior and applying it to empirical data. It is shown that uncertainty regarding the price of recycled materials may induce a risk neutral municipality to prefer landfill disposal, even when recycling is less expensive. A model is developed to describe the switching process and estimate its parameters using empirical data from 79 municipalities in Israel. The model is then used to predict municipalities' recycling adoption decisions under various assumptions regarding price uncertainty. The results support the hypothesis that price uncertainty is a major obstacle for recycling. Finally, several options for price stabilization are sketched and it is argued that these policies may be effective in establishing viable recycling markets.  相似文献   

20.
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   

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