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1.
Financial analytical models of waste management systems have often found that recycling costs exceed direct benefits, and in order to economically justify recycling activities, externalities such as household expenses or environmental impacts must be invoked. Certain more empirically based studies have also found that recycling is more expensive than disposal. Other work, both through models and surveys, have found differently. Here we present an empirical systems model, largely drawn from a suburban Long Island municipality. The model accounts for changes in distribution of effort as recycling tonnages displace disposal tonnages, and the seven different cases examined all show that curbside collection programs that manage up to between 31% and 37% of the waste stream should result in overall system savings. These savings accrue partially because of assumed cost differences in tip fees for recyclables and disposed wastes, and also because recycling can result in a more efficient, cost-effective collection program. These results imply that increases in recycling are justifiable due to cost-savings alone, not on more difficult to measure factors that may not impact program budgets.  相似文献   

2.
Recycling and reusing recyclables is an important way to solve the municipal solid waste (MSW) problem. As the collection of solid waste takes up the largest percentage of MSW management budgets, improving the collection of recyclables is important. Since the decline of government-run waste buying depots in the late 1980s, the collection of recyclables from households and waste deposit sites in China is done by buyers with small informal bases and waste pickers, who are usually unskilled rural people who have come to the cities. Because of this, the current system is seen to have social problems. So, the recyclable collection system has both social as well as economic significance. China is in the process of rapid industrialization and urbanization, and a new mode of community collection system is emerging. It operates by market mechanisms, with waste collection companies that are supported by the municipal government, establishing recycle service sites, and employing workers to buy recyclables door-to-door. This paper is a case study of the new system in the Haidian District, Beijing. It summarizes the system, compares it to experiences in other countries and discusses whether the new approach contributes to resources recycling in China.  相似文献   

3.
The state of recycling in Taiwan has seen significant achievements due to various recycling policies implemented by environmental agencies in recent years. These policies include the "Keep Trash Off the Ground" (KTOG) measure, the "Four-in-One Recycling Plan", the per-bag trash collection fee and mandatory garbage sorting. An important question worthy of study is which of these policies has had a more pervasive and critical impact on the outcome of recycling. For example, there is evidence that the KTOG measure made it more convenient for people to begin recycling. This study therefore first analyzed the monthly data over the past decade on the amounts of recyclables in Taiwan's three major cities. By examining time series plots and employing an analysis of the time series intervention model, we can better understand the extent of the effects of the KTOG measure on these cities' amounts of recyclables. The same effects were also analyzed for the mandatory garbage sorting policy and the per-bag trash collection fee. Results show that the KTOG measure, essentially a change in refuse collection practice, presented consistent and significant effects on these cities' amounts of recyclables. It is suggested that the key to improving participation in a recycling program in waste management is for techniques to be tailored to actual settings in a way that facilitates citizen cooperation.  相似文献   

4.
Recycling of paper and glass from household waste is an integrated part of waste management in Denmark, however, increased recycling is a legislative target. The questions are: how much more can the recycling rate be increased through improvements of collection schemes when organisational and technical limitations are respected, and what will the environmental and economic consequences be? This was investigated in a case study of a municipal waste management system. Five scenarios with alternative collection systems for recyclables (paper, glass, metal and plastic packaging) were assessed by means of a life cycle assessment and an assessment of the municipality’s costs. Kerbside collection would provide the highest recycling rate, 31% compared to 25% in the baseline scenario, but bring schemes with drop-off containers would also be a reasonable solution. Collection of recyclables at recycling centres was not recommendable because the recycling rate would decrease to 20%. In general, the results showed that enhancing recycling and avoiding incineration was recommendable because the environmental performance was improved in several impact categories. The municipal costs for collection and treatment of waste were reduced with increasing recycling, mainly because the high cost for incineration was avoided. However, solutions for mitigation of air pollution caused by increased collection and transport should be sought.  相似文献   

5.
As an economically developing country, Turkey has very well operated integrated solid waste management applications structured on modern facilities, besides over 2,000 scattered open dump areas in the country. Integrated waste management applications seem eligible for the metropolitan cities like Istanbul and Izmit (Kocaeli). Attempts have not been encouraging for the scattered regional settlements using central storage sites due to financial shortages and received rejections from nearby settlements. Small-scale compact solid waste management systems with materials recycling and composting can be more suitable alternatives in the small-scale regional settlements. The major constituents of municipal solid waste are organic in nature and approximately a quarter of municipal solid waste is recyclable. Although paper, including cardboard, is the main constituent, the composition of recyclable waste varies strongly by the source or the type of collection point. Solid wastes need primary treatment in order to be suitable for incineration and composting. Turkey needs to give more emphasis on the usage of modern solid waste removal technologies to overcome the overgrowing solid waste disposal problems.  相似文献   

6.
The aim of this study is to investigate waste streams as a source of recyclable raw material for fiber composite production. Globally, vast volumes of waste are produced daily that are not recycled effectively. In this work, three different raw material sources are examined; industrial, construction and municipal solid waste streams. All three sources produce wastes that are currently underutilized. Usage areas for the waste material include use as a reinforcing fiber, as part of the plastic matrix or as a filler. The industrial sector produces more homogenous waste, while waste from municipalities is mixed. Irregular material flow, the varying condition of the waste and different pretreatments used pose difficulties for recycling. Furthermore, some materials are industry-specific and may be produced in only certain areas. Despite these difficulties, huge amount of potentially useful exploitable waste is available and using different waste streams as a part of wood-plastic composite production can reduce waste volumes disposed to landfill.  相似文献   

7.
The main objective of this paper was to analyse the present status of medical waste management in the Trachea region of Turkey and subsequently to draw up a policy regarded with generation, collection, on-site handling, storage, processing, recycling, transportation and safe disposal of medical wastes. This paper also presents the results of study about awareness on how to handle expired drugs. Initially all health-care establishments in Tekirda?, Edirne and Kyrklareli provinces in Trachea region were identified and the amounts of hospital wastes generated by each of them were determined. Current medical waste-management practices, including storage, collection, transportation and disposal, in surveyed establishments were identified. Finally, according to results, remedial measurements for medical waste management in these establishments were suggested. Unfortunately, medical wastes are not given proper attention and these wastes are disposed of together with municipal and industrial solid wastes. The current disposal method is both a public health and environmental hazard. When landfill sites are visited, many scavengers can be seen sorting for recyclable materials, a practice which is dangerous for the scavengers. In addition, it was found that some staff in health-care establishments are unaware of the hazard of medical wastes. It is concluded that a new management system, which consists of segregation, material substitution, minimization, sanitary landfilling and alternative medical waste treatment methods should be carried out. For the best appropriate medical waste management system, health-care establishment employers, managers and especially the members of house- keeping divisions should be involved in medical waste management practice.  相似文献   

8.
Rapid economic growth, increasing population and change in living standards contribute to increasing the generation rate of municipal solid waste (MSW) in Denizli city, like other Turkish cities. The improper and poor MSW management system (old system) in Denizli caused environmental problems originating from the uncontrolled release of methane and leachate. In addition, the disposal of recyclable materials in unsanitary landfills is responsible for the consumption and destruction of natural sources. This paper presents a general overview of old and new MSW management practices in Denizli. Detailed data on MSW management practices including collection, transportation, disposal and recycling have been presented. The amount of solid waste generated in Denizli over the last decade has increased steadily over the years, from 108,500 tons in 1995 to 179,495 tons in 2006. The average MSW generation rate was found to be 1.23kg/day per capita. The major constituent of MSW in Denizli is food waste, but the percentage of recyclable waste has increased significantly recently. Except for metal wastes, the percentages of recyclable waste materials in Denizli are higher than in all neighborhood cities. The objective of this study is to compare the old and new MSW management systems in Denizli city. The MSW management system has been changed entirely last five years. A dumpsite was closed and a sanitary landfill with a composting facility was constructed. In addition, source separated collection has been carried out since 2002. The quantity of recyclable waste collected increased from 195 to 1549 tons. The amount of recyclable waste will continue to be increased by expanding the source separation collection system to all the districts of the city and preventing scavenging. Thus, revenue from recyclable waste ($7227 in 2006) is expected to increase. In addition, the capacity of the composting facility will be increased. Most importantly, information to increase public participation and awareness in municipal recovery programs has to be provided.  相似文献   

9.
After studying the recycling collection system of polyethylene terephthalate (PET) bottles worldwide, the authors conducted an intercept survey in Beijing. Two separate questionnaires were issued, one questionnaire to PET bottle consumers and one to PET bottle recyclers. In this study, consumers are defined as people that consume PET-bottled beverages in their daily life. Recyclers were defined as those involved in the collection and recycling of PET bottles. These include scavengers, itinerant waste buyers, small community waste-buying depots, medium/large redemption depots, and recycling companies. In total, 580 surveys were completed, including 461 by consumers and 119 by recyclers. The authors found that consumption of PET bottles in Beijing was nearly 100,000 tonnes in 2012. Age, occupation, gender, and education were identified as significant factors linked to PET-bottled beverage consumption, while income was not a significant factor. 90% Of post-consumed PET bottles were collected by informal collectors (i.e., scavengers and itinerant waste buyers). The survey also found that nearly all PET bottles were reprocessed by small factories that were not designed with pollution control equipment, which allows them to offer higher prices for waste recyclable bottles. As Beijing is trying to build a formal recycling collection system for recyclables, subsidies should be given to the formal recycling sector rather than being charged land use fees, and attention should also be given to informal recyclers that make their living from the collection of recyclables. Informal and formal sectors may work together by employing the scavengers and itinerant waste buyers for the formal sectors. In addition to the recycling of PET bottles, concern should also be allocated to reduce consumption, especially among young people, as they, compared to other groups, have a stronger demand for PET-bottled beverages and will be the main body of society.  相似文献   

10.
GHG (greenhouse gas) emission factors for waste management are increasingly used, but such factors are very scarce for developing countries. This paper shows how such factors have been developed for the recycling of glass, metals (Al and Fe), plastics and paper from municipal solid waste, as well as for the composting of garden refuse in South Africa. The emission factors developed for the different recyclables in the country show savings varying from ?290 kg CO2 e (glass) to ?19 111 kg CO2 e (metals – Al) per tonne of recyclable. They also show that there is variability, with energy intensive materials like metals having higher GHG savings in South Africa as compared to other countries. This underlines the interrelation of the waste management system of a country/region with other systems, in particular with energy generation, which in South Africa, is heavily reliant on coal. This study also shows that composting of garden waste is a net GHG emitter, releasing 172 and 186 kg CO2 e per tonne of wet garden waste for aerated dome composting and turned windrow composting, respectively. The paper concludes that these emission factors are facilitating GHG emissions modelling for waste management in South Africa and enabling local municipalities to identify best practice in this regard.  相似文献   

11.
包装垃圾是由废弃的包装物产生的固体垃圾,约占我国城市生活垃圾的1/3,虽然政府进行了必要回收,但仍有1/3以上的塑料、玻璃等包装物没能被有效回收利用,成了填埋场的主要填埋物,造成了环境污染和土地、石油等不可再生资源大量浪费。从回收利用和源头减量两方面提出包装垃圾的应对,一是对包装垃圾按来源、成分等进行详细分类,并建议回收处置方法;二是从制定行业政策方面来减少过度包装和扶持再生资源行业健康发展,有效处置包装垃圾等可再生资源。  相似文献   

12.
Through an agreement with EEE producers, Swedish municipalities are responsible for collection of hazardous waste and waste electrical and electronic equipment (WEEE). In most Swedish municipalities, collection of these waste fractions is concentrated to waste recycling centres where households can source-separate and deposit hazardous waste and WEEE free of charge. However, the centres are often located on the outskirts of city centres and cars are needed in order to use the facilities in most cases. A full-scale experiment was performed in a residential area in southern Sweden to evaluate effects of a system for property-close source separation of hazardous waste and WEEE. After the system was introduced, results show a clear reduction in the amount of hazardous waste and WEEE disposed of incorrectly amongst residual waste or dry recyclables. The systems resulted in a source separation ratio of 70 wt% for hazardous waste and 76 wt% in the case of WEEE. Results show that households in the study area were willing to increase source separation of hazardous waste and WEEE when accessibility was improved and that this and similar collection systems can play an important role in building up increasingly sustainable solid waste management systems.  相似文献   

13.
Recycling of packaging wastes may be compatible with incineration within integrated waste management systems. To study this, a mathematical model is presented to calculate the fraction composition of residual municipal solid waste (MSW) only as a function of the MSW fraction composition at source and recycling fractions of the different waste materials. The application of the model to the Lisbon region yielded results showing that the residual waste fraction composition depends both on the packaging wastes fraction at source and on the ratio between that fraction and the fraction of the same material, packaging and non-packaging, at source. This behaviour determines the variation of the residual waste LHV. For 100% of paper packaging recycling, LHV reduces 4.2% whereas this reduction is of 14.4% for 100% of packaging plastics recycling. For 100% of food waste recovery, LHV increases 36.8% due to the moisture fraction reduction of the residual waste. Additionally the results evidence that the negative impact of recycling paper and plastic packaging on the LHV may be compensated by recycling food waste and glass and metal packaging. This makes packaging materials recycling and food waste recovery compatible strategies with incineration within integrated waste management systems.  相似文献   

14.
Although some of the Gulf Co-operation Council (GCC) member states have placed recycling at the top of their waste management priorities, the low cost of landfill and the availability of land, usually old sand or gravel quarries, make recycling programs infeasible, uneconomical and unachievable. The only comprehensive form of recycling available within the GCC states is recycling of paper and cartons. The majority of the GCC states never set national or regional recycling targets. The cost of recycling in the GCC states region could be moderate to high depending on the collection system selected for the recycling program. Almost all of the cities within the GCC states use mechanised systems for daily collection of municipal solid waste (MSW). Therefore, the same daily collection system used for MSW might well be used for collection of recyclable materials, both on the same day and at the same time, or according to a different timetable. This paper provides strategies for developing an effective recycling marketing program and discusses regional co-ordination options.  相似文献   

15.
Efficient recycling of solid wastes is now a global concern for a sustainable and environmentally sound management. In this study, traditional recycling pattern of solid waste was investigated in Rajshahi municipality which is the fourth largest city of Bangladesh. A questionnaire survey had been carried out in various recycle shops during April 2010 to January 2011. There were 140 recycle shops and most of them were located in the vicinity of Stadium market in Rajshahi. About 1906 people were found to be involved in recycling activities of the city. The major fraction of recycled wastes were sent to capital city Dhaka for further manufacture of different new products. Only a small amount of wastes, specially plastics, were processed in local recycle factories to produce small washing pots and bottle caps. Everyday, an estimated 28.13 tons of recycled solid wastes were handled in Rajshahi city area. This recycled portion accounted for 8.25% of the daily total generated wastes (341 ton d?1), 54.6% of total recyclable wastes (51.49 ton d?1) and 68.29% of readily recyclable wastes (41.19 ton d?1). Major recycled materials were found to be iron, glass, plastic, and papers. Only five factories were involved in preliminary processing of recyclable wastes. Collecting and processing secondary materials, manufacturing recycled-content products, and then buying recycled products created a circle or loop that ensured the overall success of recycling and generated a host of financial, environmental, and social returns.  相似文献   

16.
Sustainable recycling of municipal solid waste in developing countries   总被引:3,自引:0,他引:3  
This research focuses on recycling in developing countries as one form of sustainable municipal solid waste management (MSWM). Twenty-three case studies provided municipal solid waste (MSW) generation and recovery rates and composition for compilation and assessment. The average MSW generation rate was 0.77 kg/person/day, with recovery rates from 5-40%. The waste streams of 19 of these case studies consisted of 0-70% recyclables and 17-80% organics. Qualitative analysis of all 23 case studies identified barriers or incentives to recycling, which resulted in the development of factors influencing recycling of MSW in developing countries. The factors are government policy, government finances, waste characterization, waste collection and segregation, household education, household economics, MSWM (municipal solid waste management) administration, MSWM personnel education, MSWM plan, local recycled-material market, technological and human resources, and land availability. Necessary and beneficial relationships drawn among these factors revealed the collaborative nature of sustainable MSWM. The functionality of the factor relationships greatly influenced the success of sustainable MSWM. A correlation existed between stakeholder involvement and the three dimensions of sustainability: environment, society, and economy. The only factors driven by all three dimensions (waste collection and segregation, MSWM plan, and local recycled-material market) were those requiring the greatest collaboration with other factors.  相似文献   

17.
The aim of this study was to provide policy-makers and waste management planners with information about how recycling programs affect the quantities of specific materials recycled and disposed of. Two questions were addressed: which factors influence household waste generation and pathways? and how reliable are official waste data? Household waste flows were studied in 35 Swedish municipalities, and a wide variation in the amount of waste per capita was observed. When evaluating the effect of different waste collection policies, it was found to be important to identify site-specific factors influencing waste generation. Eleven municipal variables were investigated in an attempt to explain the variation. The amount of household waste per resident was higher in populous municipalities and when net commuting was positive. Property-close collection of dry recyclables led to increased delivery of sorted metal, plastic and paper packaging. No difference was seen in the amount of separated recyclables per capita when weight-based billing for the collection of residual waste was applied, but the amount of residual waste was lower. Sixteen sources of error in official waste statistics were identified and the results of the study emphasize the importance of reliable waste generation and composition data to underpin waste management policies.  相似文献   

18.
The use of recyclable materials has been continuously increasing worldwide due to economic, environmental, and technological developments. Not reusing recyclable materials means that they will be degraded or corroded, and then completely destroyed by nature, thus representing a waste of resources and much environmental damage. To increase both academic and public awareness of recycling, the authors have developed a three-credit-hour recycling course entitled “Recycling of Engineering Materials” at the College of Engineering at Wichita State University, which was taught in spring 2008 and 2010. The lectures focused on basic characterization and separation techniques of recyclable materials, recycled products, environmental concerns, and potential commercial applications. Throughout the lectures, students were expected to gain an understanding of recycling concepts, processing techniques, recent progress on recycling, as well as health issues relating to toxic and hazardous materials and their handling procedures. The survey results confirmed that the course is well established and understood by the undergraduate and graduate students.  相似文献   

19.
Solid waste management (SWM) facilities are crucial for environmental management and public health in urban regions. Due to the waste management hierarchy, one of the greatest challenges that organizations face today is to figure out how to diversify the treatment options, increase the reliability of infrastructure systems, and leverage the redistribution of waste streams among incineration, compost, recycling, and other facilities to their competitive advantage region wide. Systems analysis plays an important role for regionalization assessment of integrated SWM systems, leading to provide decision makers with break-through insights and risk-informed strategies. This paper aims to apply a minimax regret optimization analysis for improving SWM strategies in the Lower Rio Grande Valley (LRGV), an economically fast growing region in the US. Based on different environmental, economic, legal, and social conditions, event-based simulation in the first stage links estimated waste streams in major cities in LRGV with possible solid waste management alternatives. The optimization analysis in the second stage emphasizes the trade-offs and associated regret evaluation with respect to predetermined scenarios. Such optimization analyses with multiple criteria have featured notable successes, either by public or private efforts, in diverting recyclables, green waste, yard waste, and biosolids from the municipal solid waste streams to upcoming waste-to-energy, composting, and recycling facilities. Model outputs may link prescribed regret scenarios in decision making with various scales of regionalization policies. The insights drawn from the system-oriented, forward-looking, and preventative study can eventually help decision-makers and stakeholders gain a scientific understanding of the consequences of short-term and long-term decisions relating to sustainable SWM in the fast-growing US-Mexico borderland.  相似文献   

20.
Composition and quantity per person of municipal solid waste (MSW) have been analyzed in six municipalities in southern Sweden with similar socio-economic conditions but with different collection systems. Samples of residual waste have been sorted, classified and weighed in 21 categories during 26 analyses that took place from 1998-2004. Collection data of the total waste flow, including source sorted recycling materials, in the same area have been compiled and compared. Multivariate data analyses have been applied. Weight-based billing reduced delivered amounts of residual household waste by 50%, but it is unknown to what extent improper material paths had developed. With curbside collection more metal, plastic and paper packaging was separated and left to recycling. When separate collection of biodegradables was included in the curbside system, the overall sorting of dry recyclables increased. The large uncertainty associated with waste composition analyses makes it difficult to draw strong conclusions regarding the effects on specific recyclables or the changes in the composition of the residual waste.  相似文献   

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