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1.
Providing good solid waste management (SWM) services while also ensuring financial sustainability of the system continues to be a major challenge in cities of developing countries. Bahir Dar in northwestern Ethiopia outsourced municipal waste services to a private waste company in 2008. While this institutional change has led to substantial improvement in the cleanliness of the city, its financial sustainability remains unclear. Is the private company able to generate sufficient revenues from their activities to offset the costs and generate some profit?This paper presents a cost-revenue analysis, based on data from July 2009 to June 2011. The analysis reveals that overall costs in Bahir Dar’s SWM system increased significantly during this period, mainly due to rising costs related to waste transportation. On the other hand, there is only one major revenue stream in place: the waste collection fee from households, commercial enterprises and institutions. As the efficiency of fee collection from households is only around 50%, the total amount of revenues are not sufficient to cover the running costs. This results in a substantial yearly deficit. The results of the research therefore show that a more detailed cost structure and cost-revenue analysis of this waste management service is important with appropriate measures, either by the privates sector itself or with the support of the local authorities, in order to enhance cost efficiency and balance the cost-revenues towards cost recovery. Delays in mitigating the evident financial deficit could else endanger the public-private partnership (PPP) and lead to failure of this setup in the medium to long term, thus also endangering the now existing improved and currently reliable service.We present four options on how financial sustainability of the SWM system in Bahir Dar might be enhanced: (i) improved fee collection efficiency by linking the fees of solid waste collection to water supply; (ii) increasing the value chain by sales of organic waste recycling products; (iii) diversifying revenue streams and financing mechanisms (polluter-pays-, cross-subsidy- and business-principles); and (iv) cost reduction and improved cost-effectiveness.We argue that in a PPP setup such as in Bahir Dar, a strong alliance between the municipality and private enterprise is important so that appropriate solutions for improved financial sustainability of a SWM system can be sought and implemented.  相似文献   

2.
Integrated solid waste management based on the 3R approach   总被引:1,自引:0,他引:1  
Integrated solid waste management (ISWM) based on the 3R approach (reduce, reuse, and recycle) is aimed at optimizing the management of solid waste from all the waste-generating sectors (municipal, construction and demolition, industrial, urban agriculture, and healthcare facilities) and involving all the stakeholders (waste generators, service providers, regulators, government, and community/neighborhoods). This article discusses the concept of solid waste management (SWM). Initially, SWM was aimed at reducing the risks to public health, and later the environmental aspect also became an important focus of SWM. Recently, another dimension is becoming a critical factor for SWM, i.e., resource conservation and resource recovery. Hence, the 3R approach is becoming a guiding factor for SWM. On the one hand, 3R helps to minimize the amount of waste from generation to disposal, thus managing the waste more effectively and minimizing the public health and environmental risks associated with it. On the other hand, resource recovery is maximized at all stages of SWM. Lately, the new concept of ISWM has been introduced to streamline all the stages of waste management, i.e., source separation, collection and transportation, transfer stations and material recovery, treatment and resource recovery, and final disposal. It was originally targeted at municipal solid waste management (MSWM), but now the United Nations Environment Programme (UNEP) is promoting this concept to cover all waste generating sectors to optimize the level of material and resource recovery for recycling as well as to improve the efficiency of waste management services. The ISWM concept is being transformed into ISWM systems to replace conventional SWM systems. This article further discusses the implementation process for ISWM. The process includes a baseline study on the characterization and quantification of waste for all waste generating sectors within a city, assessment of current waste management systems and practices, target setting for ISWM, identification of issues of concern and suggestions from stakeholders, development of a draft ISWM plan, preparation of an implementation strategy, and establishment of a monitoring and feedback system. UNEP is assisting member countries and their cities to develop an ISWM plan covering all the waste generating sectors within a specific geographical or administrative area such as a city or municipality. This umbrella approach is useful to generate sufficient volumes of recycling materials required to make recycling industries feasible. This is also helpful for efficient reallocation of resources for SWM such as collection vehicles, transfer stations, treatment plants, and disposal sites. UNEP is assisting cities to develop and implement ISWM based on the 3R approach. These experiences could be useful for other countries to develop and implement ISWM to achieve improved public health, better environmental protection, and resource conservation and resource recovery.  相似文献   

3.
This paper presents an overview of current solid waste management (SWM) practices in Kolkata, India and suggests solutions to some of the major problems. More than 2920ton/d of solid waste are generated in the Kolkata Municipal Corporation (KMC) area and the budget allocation for 2007-2008 was Rs. 1590 million (US$40 million), which amounts to Rs. 265/cap-y (US$6.7/cap-d) on SWM. This expenditure is insufficient to provide adequate SWM services. Major deficiencies were found in all elements of SWM. Despite 70% of the SWM budget being allocated for collection, collection efficiency is around 60-70% for the registered residents and less than 20% for unregistered residents (slum dwellers). The collection process is deficient in terms of manpower and vehicle availability. Bin capacity provided is adequate but locations were found to be inappropriate, thus contributing to the inefficiency of the system. At this time, no treatment is provided to the waste and waste is dumped on open land at Dhapa after collection. Lack of suitable facilities (equipment and infrastructure) and underestimates of waste generation rates, inadequate management and technical skills, improper bin collection, and route planning are responsible for poor collection and transportation of municipal solid wastes.  相似文献   

4.
Despite being in operation for more than 7 years now, privatised solid waste management (SWM) service in Tanzania has not been formally assessed. This is the premise for the techno-social performance assessment model for SWM contractors, which is presented in this paper. This paper outlines the background of SWM privatisation in Dar es Salaam City in addition to describing and demonstrating the application of the assessment model. The model has three components: service beneficiaries' assessment sub-model, service area technical assessment sub-model, and contractors' attributes sub-model. The model can be used to assess the performance of SWM contractors and in so doing provide data for assessing SWM privatisation as a whole. In the application of the model presented in this paper scores for 5 assessed contractors are in the range 24-65%. The contractor who scored highest is also the most experienced and also the best equipped. Nevertheless, all contractors scored poorly with the respect to their ability and attributes in SWM mainly because most of them are new to the solid waste management field.  相似文献   

5.
Pneumatic waste collection systems are becoming increasingly popular in new urban residential areas, and an attractive alternative to conventional vehicle-operated municipal solid waste (MSW) collection also in ready-built urban areas. How well pneumatic systems perform in ready-built areas is, however, an unexplored topic. In this paper, we analyze how a hypothetical stationary pneumatic waste collection system compares economically to a traditional vehicle-operated door-to-door collection system in an existing, densely populated urban area. Both pneumatic and door-to-door collection systems face disadvantages in such areas. While buildings and fixed city infrastructure increase the installation costs of a pneumatic system in existing residential areas, the limited space for waste transportation vehicles and containers cause problems for vehicle-operated waste collection systems. The method used for analyzing the cost effects of the compared waste collection systems in our case study takes into account also monetized environmental effects of both waste collection systems. As a result, we find that the door-to-door collection system is economically almost six times more superior. The dominant cost factor in the analysis is the large investment cost of the pneumatic system. The economic value of land is an important variable, as it is able to reverse the results, if the value of land saved with a pneumatic system is sufficiently high.  相似文献   

6.
Problems associated with solid waste management (SWM) service provision in developing countries are reaching an ever increasing magnitude, leading to considerable adverse impacts on the environment and quality of life of the inhabitants. Such problems are usually associated with limited managerial, technical and financial capabilities of municipal authorities. Municipal authorities in Egypt that are responsible for SWM services have always been accused of providing a less than satisfactory service, leading to huge quantities of solid waste being uncollected. This study assesses the potential for the provision of an effective and sustainable service, by estimating willingness of the residents to pay for such a service and the cost involved in its provision. The study covered the Rosetta urban centre and its adjacent areas, which are located in the northwestern part of the Nile Delta. It was found that, from an economic perspective, a viable SWM service could be provided in the study area using local funds. In order to increase the likelihood of success of such a service, it may be provided by a local firm or a cooperative to be established for that purpose.  相似文献   

7.
Solid waste management (SWM) services have consistently failed to keep up with the vast amount of solid waste produced in urban areas. There is not currently an efficient system in place for the management, storage, collection, and transportation of solid waste. Kathmandu City, an important urban center of South Asia, is no exception. In Kathmandu Metropolitan City, solid waste generation is predicted to be 1091 m(3)/d (245 tons/day) and 1155 m(3)/d (260 tons/day) for the years 2005 and 2006, respectively. The majority (89%) of households in Kathmandu Metropolitan City are willing to segregate the organic and non-organic portions of their waste. Overall collection efficiency was 94% in 2003. An increase in waste collection occurred due to private sector involvement, the shutdown of the second transfer station near the airport due to local protest, a lack of funding to maintain trucks/equipment, a huge increase in plastic waste, and the willingness of people to separate their waste into separate bins. Despite a substantial increase in total expenditure, no additional investments were made to the existing development plan to introduce a modern disposal system due to insufficient funding. Due to the lack of a proper lining, raw solid waste from the existing dumping site comes in contact with river water directly, causing severe river contamination and deteriorating the quality of the water.  相似文献   

8.
Solid waste management (SWM) has become an issue of increasing global concern as urban populations continue to rise and consumption patterns change. The health and environmental implications associated with SWM are mounting in urgency, particularly in the context of developing countries. While systems analyses largely targeting well-defined, engineered systems have been used to help SWM agencies in industrialized countries since the 1960s, collection and removal dominate the SWM sector in developing countries. This review contrasts the history and current paradigms of SWM practices and policies in industrialized countries with the current challenges and complexities faced in developing country SWM. In industrialized countries, public health, environment, resource scarcity, climate change, and public awareness and participation have acted as SWM drivers towards the current paradigm of integrated SWM. However, urbanization, inequality, and economic growth; cultural and socio-economic aspects; policy, governance, and institutional issues; and international influences have complicated SWM in developing countries. This has limited the applicability of approaches that were successful along the SWM development trajectories of industrialized countries. This review demonstrates the importance of founding new SWM approaches for developing country contexts in post-normal science and complex, adaptive systems thinking.  相似文献   

9.
The increasing requirement for Solid Waste Management (SWM) has become a significant challenge for municipal authorities. A number of integrated systems and methods have introduced to overcome this challenge. Many researchers have aimed to develop an ideal SWM system, including approaches involving software-based routing, Geographic Information Systems (GIS), Radio-frequency Identification (RFID), or sensor intelligent bins. Image processing solutions for the Solid Waste (SW) collection have also been developed; however, during capturing the bin image, it is challenging to position the camera for getting a bin area centralized image. As yet, there is no ideal system which can correctly estimate the amount of SW. This paper briefly discusses an efficient image processing solution to overcome these problems. Dynamic Time Warping (DTW) was used for detecting and cropping the bin area and Gabor wavelet (GW) was introduced for feature extraction of the waste bin image. Image features were used to train the classifier. A Multi-Layer Perceptron (MLP) classifier was used to classify the waste bin level and estimate the amount of waste inside the bin. The area under the Receiver Operating Characteristic (ROC) curves was used to statistically evaluate classifier performance. The results of this developed system are comparable to previous image processing based system. The system demonstration using DTW with GW for feature extraction and an MLP classifier led to promising results with respect to the accuracy of waste level estimation (98.50%). The application can be used to optimize the routing of waste collection based on the estimated bin level.  相似文献   

10.
The new city of Abuja provided an opportunity to avoid some of the environmental problems associated with other major cities in Africa. The current status of solid waste management in Abuja has been reviewed and recommendations for improvements are made. The existing solid waste management system is affected by unfavourable economic, institutional, legislative, technical and operational constraints. A reliable waste collection service is needed and waste collection vehicles need to be appropriate to local conditions. More vehicles are required to cope with increasing waste generation. Wastes need to be sorted at source as much as possible, to reduce the amount requiring disposal. Co-operation among communities, the informal sector, the formal waste collectors and the authorities is necessary if recycling rates are to increase. Markets for recycled materials need to be encouraged. Despite recent improvements in the operation of the existing dumpsite, a properly sited engineered landfill should be constructed with operation contracted to the private sector. Wastes dumped along roads, underneath bridges, in culverts and in drainage channels need to be cleared. Small-scale waste composting plants could promote employment, income generation and poverty alleviation. Enforcement of waste management legislation and a proper policy and planning framework for waste management are required. Unauthorized use of land must be controlled by enforcing relevant clauses in development guidelines. Accurate population data is necessary so that waste management systems and infrastructure can be properly planned. Funding and affordability remain major constraints and challenges.  相似文献   

11.
This paper presents a system dynamics computer model to predict solid waste generation, collection capacity and electricity generation from solid waste and to assess the needs for waste management of the urban city of Dhaka, Bangladesh. Simulated results show that solid waste generation, collection capacity and electricity generation potential from solid waste increase with time. Population, uncleared waste, untreated waste, composite index and public concern are projected to increase with time for Dhaka city. Simulated results also show that increasing the budget for collection capacity alone does not improve environmental quality; rather an increased budget is required for both collection and treatment of solid wastes of Dhaka city. Finally, this model can be used as a computer laboratory for urban solid waste management (USWM) policy analysis.  相似文献   

12.
This paper analyses the evolution of national solid waste policy in Peru and the increasing relevance of informal recycling. Despite this rise in relevance, source separation and incorporation of informal recyclers within municipal plans is still slow, and collection of mixed waste is being considered. Waste collection and transportation costs represent the main share in municipal budgets and this research calculates cost reductions as a result of informal recycling and waste picking. The city of Chiclayo in Peru is presented as a case study. The paper finds that so far, waste picking has resulted in a reduction of two collection rounds but not a reduction in the number of vehicles collecting waste. Looking to the future, recovery of the remaining materials will not have an effect on collection rounds and number of vehicles. The research concludes that synergy between municipal systems and informal recycling can be maximized if new operational conditions are implemented. It introduces the concepts of “critical work shift,” which is the time of the day when the system requires maximum quantity of resources (i.e. vehicle-hours), and “sensitivity to variations in waste amounts,” and proposes strategies to promote recycling based on these new operational concepts.  相似文献   

13.
The population of Lagos, the largest city in Nigeria, increased seven times from 1950 to 1980 with a current population of over 10 million inhabitants. The majority of the city's residents are poor. The residents make a heavy demand on resources and, at the same time, generate large quantities of solid waste. Approximately 4 million tonnes of municipal solid waste (MSW) is generated annually in the city, including approximately 0.5 million of untreated industrial waste. This is approximately 1.1 kg/cap/day. Efforts by the various waste management agencies set up by the state government to keep its streets and neighborhoods clean have achieved only minimal success. This is because more than half of these wastes are left uncollected from the streets and the various locations due to the inadequacy and inefficiency of the waste management system. Whilst the benefits of proper solid waste management (SWM), such as increased revenues for municipal bodies, higher productivity rate, improved sanitation standards and better health conditions, cannot be overemphasized, it is important that there is a reduction in the quantity of recoverable materials in residential and commercial waste streams to minimize the problem of MSW disposal. This paper examines the status of recovery and recycling in current waste management practice in Lagos, Nigeria. Existing recovery and recycling patterns, recovery and recycling technologies, approaches to materials recycling, and the types of materials recovered from MSW are reviewed. Based on these, strategies for improving recovery and recycling practices in the management of MSW in Lagos, Nigeria are suggested.  相似文献   

14.
Mismanagement of solid waste leads to public health risks, adverse environmental impacts and other socio-economic problems. This is obvious in many developing countries around the world. Currently, several countries have realized that the way they manage their solid wastes does not satisfy the objectives of sustainable development. Therefore, these countries, including Jordan, which forms the case study presented here, have decided to move away from traditional solid waste management (SWM) options to more integrated solid waste management approaches. Unfortunately, in many developing countries like Jordan, the lack of adequate resources to implement the necessary changes is posing a serious obstacle. The present paper discusses the various practices and challenges of solid waste management in Jordan from both a technical and economic perspective. An overview of the current practices and their environmental implications in three major cities of the country, which generate more than 70% of the country's solid waste, is presented. Recent literature on solid waste management in Jordan has been reviewed; and data on the total amount of municipal solid waste generated, compositional variations over the last two decades, and future projections are presented. The necessity, importance and needs of solid waste recovery and reuse are identified. The review of the legal frameworks indicated that there is a need for detailed and clear regulations dealing specifically with solid waste. The service cost analysis revealed that none of the municipalities in Jordan sufficiently recover the cost of the services, with more than 50% being subsidized from the municipalities' budgets. The allocation of the available resources was analyzed and service performance indicators assessed. Factors that should be taken into consideration when making the decision to move from a traditional SWM approach to a more integrated approach are highlighted and suggestions for a more smooth transition are recommended.  相似文献   

15.
The hypothesis of this research was that attitudes about the management of biodegradable municipal waste (BMW) are spatially variable, even within a city of modest (1.2 million) population. For a select number of representative electoral districts in the Dublin, Ireland region, residents were surveyed regarding attitudes towards waste management in general, and BMW management in particular. A total of 850 survey responses were collected. Door-to-door interviews produced 688 responses in the residential sector; these were supplemented by 162 responses to a web-based survey.The surveys revealed that the majority of households use local authority, rather than private, waste collection services (both are available). The majority of residents, regardless of the local authority in which they live, were satisfied with their waste management service. “Reducing the quantity of waste generated” was regarded the most important future issue for 28% of residential respondents. Statistical analyses of the survey responses showed that the local authority in which respondents resided significantly influenced most responses (including waste collection service used, waste service satisfaction and backyard composting activity). Many responses (including waste service satisfaction, waste management influences) were also significantly related to the respondents’ personal characteristics (e.g., education level, type of accommodation, age, etc.). These statistical results proved the hypothesis of the research and demonstrated that waste management initiatives designed for one area of the city (or, indeed, for uniform application to the city as a whole) could ignore the needs of other areas. The survey responses suggest that targeted intervention strategies would lead to improved diversion rates of BMW from landfill, a requirement of the Landfill Directive 1999/31/EC.  相似文献   

16.
Waste collection is one of the life cycle phases that influence the environmental sustainability of waste management. Pneumatic waste collection systems represent a new way of arranging waste collection in densely populated urban areas. However, limited information is available on the environmental impacts of this system. In this study, we compare the environmental sustainability of conventional door-to-door waste collection with its hypothetical pneumatic alternative. Furthermore, we analyse whether the size of the hypothetical pneumatic system, or the number of waste fractions included, have an impact on the results. Environmental loads are calculated for a hypothetical pneumatic waste collection system modelled on an existing dense urban area in Helsinki, Finland, and the results are compared to those of the prevailing, container-based, door-to-door waste collection system. The evaluation method used is the life-cycle inventory (LCI). In this study, we report the atmospheric emissions of greenhouse gases (GHG), SO(2) and NO(x). The results indicate that replacing the prevailing system with stationary pneumatic waste collection in an existing urban infrastructure would increase total air emissions. Locally, in the waste collection area, emissions would nonetheless diminish, as collection traffic decreases. While the electricity consumption of the hypothetical pneumatic system and the origin of electricity have a significant bearing on the results, emissions due to manufacturing the system's components prove decisive.  相似文献   

17.
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   

18.
Solid waste management (SWM) is a multidimensional challenge faced by urban authorities, especially in developing countries like Bangladesh. We investigated per capita waste generation by residents, its composition, and the households' attitudes towards waste management at Rahman Nagar Residential Area, Chittagong, Bangladesh. The study involved a structured questionnaire and encompassed 75 households from five different socioeconomic groups (SEGs): low (LSEG), lower middle (LMSEG), middle (MSEG), upper middle (UMSEG) and high (HSEG). Wastes, collected from all of the groups of households, were segregated and weighed. Waste generation was 1.3kg/household/day and 0.25kg/person/day. Household solid waste (HSW) was comprised of nine categories of wastes with vegetable/food waste being the largest component (62%). Vegetable/food waste generation increased from the HSEG (47%) to the LSEG (88%). By weight, 66% of the waste was compostable in nature. The generation of HSW was positively correlated with family size (r(xy)=0.236, p<0.05), education level (r(xy)=0.244, p<0.05) and monthly income (r(xy)=0.671, p<0.01) of the households. Municipal authorities are usually the responsible agencies for solid waste collection and disposal, but the magnitude of the problem is well beyond the ability of any municipal government to tackle. Hence dwellers were found to take the service from the local waste management initiative. Of the respondents, an impressive 44% were willing to pay US$0.3 to US$0.4 per month to waste collectors and it is recommended that service charge be based on the volume of waste generated by households. Almost a quarter (22.7%) of the respondents preferred 12-1pm as the time period for their waste to be collected. This study adequately shows that household solid waste can be converted from burden to resource through segregation at the source, since people are aware of their role in this direction provided a mechanism to assist them in this pursuit exists and the burden is distributed according to the amount of waste generated.  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.
Developing nations have various problems regarding municipal solid waste (MSW). Therefore, to carry out a systematic review of the MSW problems in the target area and to formulate a well-considered management plan, it is extremely important to understand the present MSW flow in the region. One of the authors participated in the nine solid waste management (SWM) studies in developing nations undertaken under the technical cooperation program of the Japan International Cooperation Agency (JICA). Based on these studies, this paper reviews the results of research in developing countries regarding different MSW streams, the factors that cause the differences, and the elements considered to have the most impact on those streams. This research identifies several issues regarding MSW streams in developing nations. The MSW generation rate per capita in developing countries is generally said to grow in proportion to the GNP. However, the findings of this research show no correlation between the two; instead, there is a relationship between the GNP and the collection rate. To formulate proper future MSW management plans in countries with low collection rates, it is very important to forecast the rates of self-disposed and recycled waste, and their fluctuations. These are affected by urban structure, collection services, etc. Received: January 27, 2000 / Accepted: July 19, 2000  相似文献   

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