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1.
This study was undertaken to evaluate the quantity and composition of household solid waste to identify opportunities for waste recycling in Can Tho city, the capital city of the Mekong Delta region in southern Vietnam. Two-stage survey of 100 households was conducted for dry season and rainy season in 2009. Household solid waste was collected from each household and classified into 10 physical categories and 83 subcategories. The average household solid waste generation rate was 285.28 g per capita per day. The compostable and recyclable shares respectively accounted for 80.02% and 11.73%. The authors also analyzed the relations between some socioeconomic factors and household solid waste generation rates by physical categories and subcategories. The household solid waste generation rate per capita per day was positively correlated with the population density and urbanization level, although it was negatively correlated with the household size. The authors also developed mathematical models of correlations between the waste generation rates of main physical categories and relevant factors, such as household size and household income. The models were proposed by linear models with three variables to predict household solid waste generation of total waste, food waste, and plastic waste. It was shown that these correlations were weak and a relationship among variables existed. Comparisons of waste generation by physical compositions associated with different factors, such as seasonal and daily variation were conducted. Results presented that the significant average differences were found by the different seasons and by the different days in a week; although these correlations were weak. The greenhouse gas baseline emission was also calculated as 292.25 g (CO2 eq.) per capita per day from biodegradable components.  相似文献   

2.
This paper clarifies household income, living and working conditions of dumpsite waste pickers at Bantar Gebang final disposal site for municipal solid waste generated in Jakarta, and investigates the feasibility of integrating the informal sector into formal waste management in Indonesia. The first author did fieldwork for totally 16 months at the site and quantitative field surveys were conducted twice during the period. All respondents in the first round quantitative survey (n = 1390) were categorized as follows: waste pickers, family workers, wage labors, bosses, family of the bosses, housewives, pupils/students, preschoolers, the unemployed, and others. Based on the results of the second round quantitative survey (n = 69 households), their average household income was estimated to be approximately US 216 dollars per month (n = 59 households), which was virtually equivalent to the minimum wage in Jakarta in 2013. Living conditions of scavengers at the site were horrible, and their working conditions were dangerous due to medical waste and other sharp waste. Polluted groundwater was one of the serious environmental problems at the site. Despite the social, health and environmental problems, they were attracted to the freedom of entering the informal recycling system in Bantar Gebang and withdrawing from the system, in which a lot of opportunities were provided for the people having few marketable skills to obtain cash earnings. The freedom of their choice should be guaranteed as a prerequisite before integrating the informal sector into formal waste management. Furthermore, special attentions are required when incomes of scavengers are the same level as minimum wages and the national economy is rapidly growing, because scavengers cannot easily change their jobs due to few marketable skills. Indonesian national waste laws and regulations should be properly applied to facilitate a socialization process at final disposal sites. Measures need to be taken to prevent children from working as informal recycling actors, especially for waste pickers aged 15 or younger.  相似文献   

3.
A questionnaire survey was conducted in 2002 on 1365 households in two prefectural-level cities in the Pearl River Delta, Jiangmen and Zhongshan. Three groups of issues are covered in this paper: 1) waste management literacy, concerns, and public participation; 2) waste recycling practices and the potential for waste avoidance; and 3) public environmental literacy. This study confirms findings from previous surveys and provides new information on important issues such as imposing monetary charges on waste and environmental activities, littering, source separation programs (SSPs), and public participation and expectations in local waste management. Saving up recyclable materials for redemption in waste depots is commonly practiced in mainland China regardless of the level of development of a city, although at the household level, high-income families tend to place less value on the revenues to be gained from redemption than lower income groups do. Data from the previous and the present studies indicate that such voluntary but largely economically driven waste recovery behavior diverts at least 10% of the household waste from the waste stream. Although uncompensated SSP is less appealing in the two cities than compensated SSP, it was found that when the median per capita income of a city reaches RMB2000 per month, a high participation rate for uncompensated waste recovery is more likely to occur. Education and income levels are the chief factors affecting littering behavior and the potential for waste avoidance. Contrary to general belief, the local Chinese community is active in microwaste management. The concern, however, is over the inability of the grassroots bureaucracy to deal with rising expectations for waste collection services and neighborhood cleanliness.  相似文献   

4.
Solid waste recycling and recovery approach can be a sustainable and effective waste management system in many growing cities of the least developed countries. In the course of achieving proper solid waste management, a lot of efforts in these countries have, however, been focused more on collection and disposal and ignored waste recycling which can result into income generation, employment creation and reduction of the waste quantities that will finally require disposal in the existing municipal landfills or disposal sites. This paper reports the findings of a study on solid waste recycling in a selected semi-planned settlement in Dar es Salaam City, Tanzania. The objective of the study was to describe the existing solid waste management in the study area with a view to identifying the waste generation rates, types of the wastes and determine the amount of waste from the settlement that can be recycled for the purpose of income generation and reduction of the total amount of waste to be disposed of. Findings from this study revealed that waste generation rate in the study area was 0.36 kg per person per day, and that out of the 14 600 kg of recyclable waste generated per year, 8030 kg or 55% can be recycled and generate a per capita income of Tsh 834 000 for waste recyclists which is more than twice the official minimum annual wage (Tsh 360 000) in Tanzania at the time of the study. The study also revealed that effective waste recycling in the study area would result in the reduction of the total waste that need to be transported for final disposal by 11%.  相似文献   

5.
The competent waste authority in the Flemish region of Belgium created the 'Implementation plan household waste 2003-2007' and the 'Implementation plan sustainable management 2010-2015' to comply with EU regulation. It incorporates European and regional requirements and describes strategies, goals, actions and instruments for the collection and treatment of household waste. The central mandatory goal is to reduce and maintain the amount of residual household waste to 150 kg per capita per year between 2010-2015. In literature, a reasonable body of information has been published on the effectiveness and efficiency of a variety of policy instruments, but the information is complex, often contradictory and difficult to interpret. The objective of this paper is to identify, through the development of a binary logistic regression model, those variables of the waste collection scheme that help municipalities to reach the mandatory 150 kg goal. The model covers a number of variables for household characteristics, provision of recycling services, frequency of waste collection and charging for waste services. This paper, however, is not about waste prevention and reuse. The dataset originates from 2003. Four out of 12 variables in the model contributed significantly: income per capita, cost of residual waste collection, collection frequency and separate curbside collection of organic waste.  相似文献   

6.
Municipal solid waste management in China: Status,problems and challenges   总被引:1,自引:0,他引:1  
This paper presents an examination of MSW generation and composition in China, providing an overview of the current state of MSW management, an analysis of existing problems in MSW collection, separation, recycling and disposal, and some suggestions for improving MSW systems in the future. In China, along with urbanization, population growth and industrialization, the quantity of municipal solid waste (MSW) generation has been increasing rapidly. The total MSW amount increased from 31.3 million tonnes in 1980 to 212 million tonnes in 2006, and the waste generation rate increased from 0.50 kg/capita/day in 1980 to 0.98 kg/capita/year in 2006. Currently, waste composition in China is dominated by a high organic and moisture content, since the concentration of kitchen waste in urban solid waste makes up the highest proportion (at approximately 60%) of the waste stream. The total amount of MSW collected and transported was 148 million tonnes in 2006, of which 91.4% was landfilled, 6.4% was incinerated and 2.2% was composted. The overall MSW treatment rate in China was approximately 62% in 2007. In 2007, there were 460 facilities, including 366 landfill sites, 17 composing plants, and 66 incineration plants. This paper also considers the challenges faced and opportunities for MSW management in China, and a number of recommendations are made aimed at improving the MSW management system.  相似文献   

7.
Municipal solid waste generation in Kathmandu, Nepal   总被引:1,自引:0,他引:1  
Waste stream characteristics must be understood to tackle waste management problems in Kathmandu Metropolitan City (KMC), Nepal. Three-stage stratified cluster sampling was used to evaluate solid waste data collected from 336 households in KMC. This information was combined with data collected regarding waste from restaurants, hotels, schools and streets. The study found that 497.3 g capita(-1) day(-1) of solid waste was generated from households and 48.5, 113.3 and 26.1 kg facility(-1) day(-1) of waste was generated from restaurants, hotels and schools, respectively. Street litter measured 69.3 metric tons day(-1). The average municipal solid waste generation rate was 523.8 metric tons day(-1) or 0.66 kg capita(-1) day(-1) as compared to the 320 metric tons day(-1) reported by the city. The coefficient of correlation between the number of people and the amount of waste produced was 0.94. Key household waste constituents included 71% organic wastes, 12% plastics, 7.5% paper and paper products, 5% dirt and construction debris and 1% hazardous wastes. Although the waste composition varied depending on the source, the composition analysis of waste from restaurants, hotels, schools and streets showed a high percentage of organic wastes. These numbers suggest a greater potential for recovery of organic wastes via composting and there is an opportunity for recycling. Because there is no previous inquiry of this scale in reporting comprehensive municipal solid waste generation in Nepal, this study can be treated as a baseline for other Nepalese municipalities.  相似文献   

8.
The selective collection and recycling of municipal solid waste are presented as stages of an integrated program of solid waste management to minimize the environmental impact of the treatment and final disposal of solid waste. Therefore, this program aims to save natural resources, such as energy and raw materials, in the manufacture of new products and to conserve areas for sites, such as to minimize the use of existing landfill sites, and to minimize the need for new waste treatment sites. A university is composed of educational professionals aware of their societal responsibilities, and, therefore, they play a fundamental role in the management of the university's solid waste. This study presents the design and implementation of a Permanent Selective Collection Program (PSCP) at the Federal University of Itajubá (Universidade Federal de Itajubá, UNIFEI), Itajubá-MG, Brazil. The material requirements for initiating the PSCP have been identified, and an action plan for continuous program improvement, which is initially based on the collection of performance indicator data for the PSCP campus, has been developed. Finally, the data from the PSCP performance indicators and software from the United States Environmental Protection Agency, the Landfill Gas Generation Model (LandGEM) and the Waste Reduction Model (WARM), were used to evaluate the impact of implementing PSCP in terms of energy and the generation of greenhouse gases (GHG). The results were promising, showing that there has been an improvement, since the inception of PSCP in 2006, in separating materials for selective collection, even though paper (41.00 wt%), plastic (6.00 wt%) and organic matter (26.00 wt%) are still highly generated wastes. The WARM simulations for a scenario in which 90% of the waste is sent for recycling resulted in an economy of −7 tCO2 or −74.91 GJ (on an energy basis). The LandGEM (USEPA) simulations estimated 1424.60 kWh of energy in the peak production year.  相似文献   

9.
The ability for small islands to meet sustainability goals is exacerbated by the costs of transporting goods on, and then, wastes off the islands. At small scales, recycling can be prohibitive and complicated by labor costs; the need to profitably recycle and manage solid waste output from tourism is complicated by scale and available technologies. A multi-year study documents the amount of solid waste generated on Great Exuma (Exuma), The Commonwealth of The Bahamas since 2010 with one year of benchmarking, then limited recycling of food waste generation by an all-inclusive resort, Sandals Emerald Bay (SEB). For the island of Exuma, the rapid increase in the rate of accumulation of solid waste associated with a large destination resort has led to an increase in pests such as rats and flies, along with an increased occurrence of fires associated with unburied solid waste. Solid waste has accumulated faster than the island solid waste management can absorb. SEB kitchen and hotel operations contributes an estimated 36% of all solid waste generated on the island, about 1752 t1 out of a total of 4841 t generated on the island in 2013 (exclusive of vegetation waste). Based on 4 weeks of benchmarking, 48.5% of all the waste coming out of the SEB resort is compostable, organic waste, but waste composition varies widely over time. Exuma Waste Management (EWM) and Recycle Exuma (RE), both privately-held Bahamian businesses, worked for one year (2012–2013) with SEB resort to implement a benchmarking and pilot recycling project to meet Earth Check green resort certification requirements. This paper outlines the costs and resources required for food waste recycling and some barriers to implementing more effective solid waste management for the tourism industry on small islands.  相似文献   

10.
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   

11.
Moving up the waste hierarchy is a key priority for UK waste policy. Waste prevention requires policy interventions to promote reuse. The term ‘reuse exchange’ has been adopted by UK policy makers to describe a variety of second-hand trading outlets including car boot sales, charity shops and online exchange sites. As waste policy is based on tonnage diverted from disposal (or landfill), policy interventions to promote reuse exchange will be based on the weight of goods estimated to be flowing through these sites. This paper uses a combination of field survey data and scale-up estimation to quantify and characterise the weight of goods exchanged at car boot sales in England in 2012. This is estimated at 50–60 000 tonnes per annum. The paper emphasises that movement up the waste hierarchy brings waste policy into closer contact with household consumption practices. It draws on qualitative research to show that, for participants, car boot sales are not associated with waste prevention. Instead, car boot sales rely on stocks of surplus household goods and exemplify the culture of thrift, which enables more, not less, consumption. The paper shows the collision between the social values that inform thrift and the environmental values that underpin reuse; and it argues that the policy goal of enhanced recovery for reuse might best be achieved by working with consumer culture. Two ways of achieving this are suggested: interventions that make it easier for consumers to do the right thing, through promoting opportunities for the circulation of stocks of surplus goods, for example, through increasing the frequency of car boot sales; and interventions which recognise that car boot sales also generate waste, which could be recovered for reuse.  相似文献   

12.
The quality of recyclable and residual municipal solid waste (MSW) is, among other factors, strongly influenced by the seasonal variation in MSW composition. However, a relatively marginal amount of published data on seasonal MSW composition especially in East European countries do not provide sufficient information on this phenomenon. This study provides results from municipal waste composition research campaigns conducted during the period of 2009–2011 in four cities of Eastern European countries (Lithuania, Russia, Ukraine and Georgia). The median monthly MSW generation values ranged from 18.70 in Kutaisi (Georgia) to 38.31 kg capita−1 month−1 in Kaunas (Lithuania). The quantitative estimation of seasonal variation was performed by fitting the collected data to time series forecasting models, such as non-parametric seasonal exponential smoothing, Winters additive, and Winters multiplicative methods.  相似文献   

13.
Industrialization and urbanization in the developing world have boosted steel demand during the recent two decades. Reliable estimates on how much steel is required for high economic development are necessary to better understand the future challenges for employment, resource management, capacity planning, and climate change mitigation within the steel sector. During their use phase, steel-containing products provide service to people, and the size of the in-use stock of steel can serve as an indicator of the total service level. We apply dynamic material flow analysis to estimate in-use stocks of steel in about 200 countries and identify patterns of how stocks evolve over time. Three different models of the steel cycle are applied and a full uncertainty analysis is conducted to obtain reliable stock estimates for the period 1700–2008.Per capita in-use stocks in countries with a long industrial history, e.g., the U.S, the UK, or Germany, are between 11 and 16 tons, and stock accumulation is slowing down or has come to a halt. Stocks in countries that industrialized rather recently, such as South Korea or Portugal, are between 6 and 10 tons per capita and grow fast. In several countries, per capita in-use stocks of steel have saturated or are close to saturation. We identify the range of saturation to be 13 ± 2 tons for the total per capita stock, which includes 10 ± 2 tons for construction, 1.3 ± 0.5 tons for machinery, 1.5 ± 0.7 tons for transportation, and 0.6 ± 0.2 tons for appliances and containers. The time series for the stocks and the saturation levels can be used to estimate future steel production and scrap supply.  相似文献   

14.
The environmental impacts of food waste management strategies and the effects of energy mix were evaluated using a life cycle assessment model, EASEWASTE. Three different strategies involving landfill, composting and combined digestion and composting as core technologies were investigated. The results indicate that the landfilling of food waste has an obvious impact on global warming, although the power recovery from landfill gas counteracts some of this. Food waste composting causes serious acidification (68.0 PE) and nutrient enrichment (76.9 PE) because of NH3 and SO2 emissions during decomposition. Using compost on farmland, which can marginally reduce global warming (−1.7 PE), acidification (−0.8 PE), and ecotoxicity and human toxicity through fertilizer substitution, also leads to nutrient enrichment as neutralization of emissions from N loss (27.6 PE) and substitution (−12.8 PE). A combined digestion and composting technology lessens the effects of acidification (−12.2 PE), nutrient enrichment (−5.7 PE), and global warming (−7.9 PE) mainly because energy is recovered efficiently, which decreases emissions including SO2, Hg, NOx, and fossil CO2 during normal energy production. The change of energy mix by introducing more clean energy, which has marginal effects on the performance of composting strategy, results in apparently more loading to acidification and nutrient enrichment in the other two strategies. These are mainly because the recovered energy can avoid fewer emissions than before due to the lower background values in power generation. These results provide quantitative evidence for technical selection and pollution control in food waste management.  相似文献   

15.
On domestic waste recycling, it was found that source separation of domestic waste in mainland China was supported by 85% of the urban population and about 11–13% of the household waste was recovered and sold by the householders for financial gains. It was also found that the lower income group tended to recover a greater portion of waste, indicating that voluntary waste recovery activities in mainland China were carried out largely due to economic reasons. Thus, the Western type of source separation program in which residents are requested to separate recyclables for the community may not be welcomed in mainland China. In Hong Kong, despite the presence of community waste recovery programs, the recovery of domestic waste is only about 6% and is therefore less than those of the mainland Chinese cities surveyed. On the choice of source separation programs, it was found that Hong Kong people ranked familiarity a more important criterion than convenience. Therefore, the collection frequency of recyclables and time and place for setting out recyclables should be as similar to those of normal waste collection as possible to attract high participation in source separation programs.  相似文献   

16.
Shanghai is the largest industrial and commercial city of China, where in-use stocks of metals are likely to be significant. The in-use stocks of copper in this city are thus established by an extensive “bottom-up” study. Spatial distribution of copper stocks within Shanghai has further been characterized for better understanding of copper utilization pattern of this city. For the year 2012, the results are a total stock of 914.6 Gg Cu, and 38.4–64.1 kg Cu per capita. Nearly 94% of copper stocks distribute in subcategories of electric power transmission and distribution, water transmission and distribution, buildings, and household durable. Features of spatial distribution show that three central districts of Jing An, Hong Kou and Huang Pu have the spatial density of more than 1 Gg/km2. And Chong Ming county and Jin Shan District have the lowest spatial density of about 0.01 Gg/km2. It has been found that the copper stock density within Shanghai is largely determined by population density and economic development level.  相似文献   

17.
Phosphorus (P) is a finite and non-substitutable resource that is essential to sustaining high levels of agricultural productivity but is also responsible for environmental problems, e.g., eutrophication. Based on the methodology of Material Flow Analysis, this study attempts to quantify all relevant flows and stocks of phosphorus (P) in Austria, with a special focus on waste and wastewater management. The system is modeled with the software STAN, which considers data uncertainty and applies data reconciliation and error propagation. The main novelty of this work lies in the high level of detail at which flows and stocks have been quantified to achieve a deeper understanding of the system and to provide a sound basis for the evaluation of various management options. The budget confirms on the one hand the dependence of mineral P fertilizer application (2 kg cap−1 yr−1), but it highlights on the other hand considerable unexploited potential for improvement. For example, municipal sewage sludge (0.75 kg cap−1 yr−1) and meat and bone meal (0.65 kg cap−1 yr−1) could potentially substitute 70% of the total applied mineral P fertilizers. However, recycling rates are low for several P flows (e.g., 27% of municipal sewage sludge; 3% of meat and bone meal). Therefore, Austria is building up a remarkable P stock (2.1 kg P cap−1 yr−1), mainly due to accumulation in landfills (1.1 kg P cap−1 yr−1) and agricultural soils (0.48 kg P cap−1 yr−1).  相似文献   

18.
Using information on a basic or “lifeline” level of domestic water use obtained from a water demand function based on a Stone–Geary utility function, a minimum water threshold of 128 m3 per household per year was estimated in a sample of municipalities in Southern Spain. As a second objective, water affordability indexes were then calculated that relate the cost of such lifeline to average municipal income levels. The analysis of the factors behind the differences in that ratio across Andalusian municipalities shows that the relative cost of purchasing the lifeline appears inversely related to average income levels, revealing an element of regressivity in the component of water tariffs affecting the least superfluous part of the household’s consumption. The main policy recommendation would involve redesigning water tariffs in order to improve access for lower income households to an amount of water sufficient to cover their basic needs. The proposed methodology could be applied to other geographical areas, both from developed and from developing countries, in order to analyze the degree of progressivity of the water tariffs currently in effect and in order to guide the design of more equitable regulatory policies.  相似文献   

19.
Algae offer a multiple-benefit opportunity as the products that can result from algal cultivation are numerous and diverse. However, commercial production of algal-derived materials is scarce and in Queensland Australia is virtually non-existent, partly due to challenges around readily available resources. In this work, the potential to regionally recycle waste nitrogen (N), phosphorus (P) and CO2 to support algal production is considered. A feature of the work is mapping the availability of the three resources for algal cultivation (N, P and CO2) together with climatic and land use considerations. Mapping resolution is defined by the boundaries of Queensland's (Australia) regional authorities. Layering the maps enables identification of regional hotspots for growing algae. Waste resources are shown to be most abundant in Mackay, Burdekin, Toowoomba, Cassowary and Bundaberg; regions which also have favourable eco-climatic conditions. Waste nitrogen is the limiting waste stream, in these and most other regions however additional requirements can be fixed atmospherically, whereas waste CO2 is shown to be abundant relative to waste nutrients. It is found that, based on the availability of waste phosphorus, the top 5 most suitable regions have sufficient resources to produce around 1.1 million t/y of algal biomass. This could potentially produce 309 ML of biodiesel which is 5% of Queensland's 2011 diesel oil sales. The outcomes of this work highlight new opportunities for industrial ecology in non-urban regions.  相似文献   

20.
This paper examines the 1-year anthropogenic stocks and flows of silver as it progresses from extraction to final disposal on the European continent. The primary flows of silver include production, fabrication and manufacturing, use, and waste management. A substance flow analysis (SFA) was used to trace the flows and inventory data, and mass balance equations were used to determine the quantity of flows. The results reveal that Europe has a low level of silver mine production (1580 Mg Ag/year) and instead relies on silver imports and the recycling of scrap in production and fabrication. In the year 1997, Europe imported 1160 Mg Ag of ore concentrate and 2010 Mg Ag of refined silver, and recycled 2750 Mg Ag of new and old scrap. There is a net addition of 3320 Mg Ag/year into silver reservoirs at the use stage. This is the result of a greater amount of silver entering the system from manufacturing than is leaving the system into waste management. The waste flow with the highest content of silver is municipal solid waste, which contains 1180 Mg Ag/year. In total, 62% of all discarded silver is recycled and 38% is sent to landfills. The results of this study and other element and material flow analyses can help guide resource managers, environmental policy makers, and environmental scientists in their efforts to increase material recovery and recycling, address resource sustainability, and ameliorate environmental problems.  相似文献   

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