Trends and problems of solid waste management in developing countries: a case study in seven Palestinian districts

There is a great interest in solving problems related to municipal solid waste (MSW) management in the Palestinian territory. However, few studies have been done to assess the extent of these problems and suggest the best alternative solutions. This study aims at assessing MSW conditions in the seven major districts in northern West Bank, Palestinian territory. The study focuses on comparing several MSW management elements (such as collection, budget, and disposal) in municipalities, village councils, and refugee camps in the studied districts and the problems faced by these institutions in handling the waste. It also provides information on MSW collection service availability and waste disposal practices in the districts studied. It was found that, although MSW collection service was available for 98% of the residents in the areas surveyed, no proper treatment or landfill procedure was followed for the collected waste in most of these areas. Instead, waste burning in open dumpsites was the most common practice. Moreover, due to inefficient collection of waste disposal fees from the residents, municipalities were forced to sometimes cut the collection service and reduce its labor force, especially in villages. The budget for MSW management was between 2% and 8% of the total budget of the municipalities studied, indicating a low priority for this issue.     

Measurement of odour with focus on sampling techniques

The treatment of waste and many manufacturing processes cause odour emissions. In order to prevent odours, the residents and businesses in the neighbourhood of such plants complain about odour, and it becomes necessary to reduce the emissions. To achieve that, the emissions have to be investigated and evaluated in a representative and reproducible manner. The DIN EN 13725 (2003) [DIN EN 13725. 2003. Luftbeschaffenheit--Bestimmung der Geruchsstoffkonzentration mit dynamischer Olfaktometrie--Air quality--Determination of odour concentration by dynamic olfactometry, Deutsche Fassung EN 13725:2003. Beuth Verlag, Berlin (DE)] provides a European standard for the measurement of odour. Nevertheless, the subject of sampling is not standardised; even though it has a substantial influence on the results of the measurements. In this paper, the odour measurement itself, as well as the different kinds of sampling methods (depending on the specific type of source), will be presented and discussed.     

Perpetual landfilling through aeration of the waste mass; lessons from test cells in Georgia (USA).

Municipal solid waste (MSW) landfills worldwide are experiencing the consequences of conventional landfilling techniques, whereby anaerobic conditions are created within the landfilled waste. Under anaerobic conditions within a landfill site slow stabilization of the waste mass occurs, producing methane, (an explosive 'green house' gas) and leachate (which can pollute groundwater) over long periods of time. As a potential solution, it was demonstrated that the aerobic degradation of MSW within a landfill can significantly increase the rate of waste decomposition and settlement, decrease the methane production and leachate leaving the system, and potentially increase the operational life of the site. Readily integrated into the existing landfill infrastructure, this approach can safely and cost-effectively convert a MSW landfill from anaerobic to aerobic degradation processes, thereby effectively composting much of the organic portions (one of the potentially polluting elements in a conventional landfill site) of the waste. This paper summarizes the successful results of two separate aerobic landfill projects located in Georgia (USA) and discusses the potential economic and environmental impacts to worldwide solid waste management practices.     

Eco-efficiency for greenhouse gas emissions mitigation of municipal solid waste management: a case study of Tianjin, China

The issue of municipal solid waste (MSW) management has been highlighted in China due to the continually increasing MSW volumes being generated and the limited capacity of waste treatment facilities. This article presents a quantitative eco-efficiency (E/E) analysis on MSW management in terms of greenhouse gas (GHG) mitigation. A methodology for E/E analysis has been proposed, with an emphasis on the consistent integration of life cycle assessment (LCA) and life cycle costing (LCC). The environmental and economic impacts derived from LCA and LCC have been normalized and defined as a quantitative E/E indicator. The proposed method was applied in a case study of Tianjin, China. The study assessed the current MSW management system, as well as a set of alternative scenarios, to investigate trade-offs between economy and GHG emissions mitigation. Additionally, contribution analysis was conducted on both LCA and LCC to identify key issues driving environmental and economic impacts. The results show that the current Tianjin’s MSW management system emits the highest GHG and costs the least, whereas the situation reverses in the integrated scenario. The key issues identified by the contribution analysis show no linear relationship between the global warming impact and the cost impact in MSW management system. The landfill gas utilization scenario is indicated as a potential optimum scenario by the proposed E/E analysis, given the characteristics of MSW, technology levels, and chosen methodologies. The E/E analysis provides an attractive direction towards sustainable waste management, though some questions with respect to uncertainty need to be discussed further.     

Urban solid waste management in Chongqing: challenges and opportunities

The dual influences of the resource supply and protection in ecological environments will pose a significant challenge to China's sustainable development. Solid waste management offers opportunities to improve profits by conserving resources and improving environmental performance. This paper examines municipal solid waste (MSW) management in urban Chongqing, the nation's fourth largest municipality after Beijing, Shanghai and Tianjin. In this paper, we will provide information on the quantity and composition of MSW, as well as give an overview of different methods for collection, transport, treatment and disposal of MSW. At present the daily amount of MSW generated per person is about 1.08 kg; food waste accounts for about 59% of total MSW. MSW in Chongqing has a higher moisture content (64.1%) and a lower LHV (3728 kJ/kg) than other cities in Asia, which is an obstruction for incineration. Landfills are the main method of disposal in Chongqing, but pollution caused by simple landfills and lack of backup MSW disposal capacity are becoming major problems in the main districts of Chongqing. In this paper, the challenges being faced and opportunities to MSW in Chongqing are analyzed and some suggestions are given for improving the MSW system in the future.     

Substance flow analysis of coplanar PCBs released from waste incineration processes

Previous reports have focused on the emission of coplanar polychlorinated biphenyls (Co-PCBs) which have a toxic mechanism similar to that of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/DFs) released from municipal solid waste (MSW) incineration. Such emissions accounted for a small percentage of all the dioxins (PCDDs/DFs and Co-PCBs) recorded at the toxicity equivalent (TEQ) level. There is, however, very little information about Co-PCBs, such as the quantities being released and their effect on overall environmental pollution. The aim of this research has been to clarify the substance flow of Co-PCBs from MSW incineration processes. The results reveal that whereas the input of Co-PCBs into the MSW incineration facilities in Kyoto City was 0.13–0.29 μg-TEQ per ton waste, the total output of Co-PCBs (the sum of Co-PCBs released from emission gas, fly ash, and bottom ash) was 4.9 μg-TEQ per ton waste. The total output was therefore found to be higher than the total input. Over 90% of the total PCBs were decomposed in the incineration process. In comparing the profiles of congeners and homologues, those in the MSW were found to be similar to those detected in the atmosphere and products containing PCBs, but different from those in the MSW incineration gas. Received: August 26, 1998 / Accepted: March 2, 1999     

Change in MSW characteristics under recent management strategies in Taiwan

Reduction and recycling initiatives such as producer responsibility and pay-as-you-throw are being implemented in Taiwan. This paper presents a study assessing the impact of recently implemented municipal solid waste (MSW) reduction and recycling management strategies on the characteristics of waste feedstock for incineration in Taiwan. Through the periodic sampling of two typical MSW incineration plants, proximate and ultimate analyses were conducted according to standard methods to explore the influence of MSW reduction and recycling management strategies on incineration feed waste characteristics. It was observed that the annual amount of MSW generated in 2005 decreased by about 10% compared to 2003 and that the characteristics of MSW have changed significantly due to recent management strategies. The heating value of the MSW generated in Taiwan increased yearly by about 5% after program implementation. A comparison of the monthly variations in chemical concentrations indicated that the chlorine content in MSW has changed. This change results from usage reduction of PVC plastic due to the recycling fund management (RFM) program, and the food waste as well as salt content reduction due to the total recycling for kitchen garbage program. This achievement will improve the reduction of dioxin emissions from MSW incineration. In summary, management strategies must be conducted in tandem with the global trend to achieve a zero-waste-discharge country. When implementing these strategies and planning for future MSW management systems, it is important to consider the changes that may occur in the composition and characteristics of MSW over time.     

Energy recovery and greenhouse gas reduction potential from food waste in Japan

Waste-to-energy is one effective waste management approach for a sustainable society. The purpose of this study was to clarify the potential for energy recovery and greenhouse gas (GHG) reduction that could be achieved by introducing anaerobic digestion (AD) facilities in the process of reconstructing aging incineration facilities in Japan. Using statistical data from 1068 incineration facilities, four future scenarios were considered and compared with the current situation. As results, compared with the current situation the amount of electricity generated could increase by 60 % in 2030, by combining AD facilities for food waste with new, high-efficiency incineration facilities for remaining municipal solid waste (MSW). From a life cycle perspective, net energy recovery in 2030 was approximately three times greater than in 2011, and GHG emission could be reduced by 27 %. The introduction of AD facilities is attractive for small authorities, which currently treat <100 t/day of MSW through incineration facilities without energy recovery. An AD facility is also beneficial for large authorities. On the contrary, in middle-scale authorities that treat 100–299 t/day of MSW, the reconstruction of incineration facilities to include electricity production capabilities requires careful consideration, because it will significantly influence energy recovery and GHG reduction effects.     

The current situation of solid waste management in China

With economic development, the quantity of solid waste is increasing rapidly in China; the total quantities of municipal solid waste (MSW), industrial solid waste (ISW), and hazardous waste (HW) in 2002 were 136.5 million tons, 945 million tons, and 10 million tons, respectively. In 2002, the quantity of MSW disposed of was 74.04 million tons, 89.30% of which was landfilled, 3.72% was incinerated, and 6.98% was composted. There are currently 651 disposal facilities for MSW in China. Mining gangue is the largest component of ISW, making up 27.5% of the total. In the Chinese industrial sector, the coal mining and processing industry contributed most to the total quantity of ISW, with 16.0% of the total quantity of ISW generated by this sector. In total, 44% of HW was recycled, 27% was stored, 13.5% was disposed of, and 15.4% was discharged. Of the total HW generated, 40% was produced by the chemical materials and chemical products industry. Five categories of HW, i.e., waste alkali, waste acid, inorganic fluoride waste, copper waste, and inorganic cyanide waste, made up 57.8% of the total HW generated. Solid waste pollution has become a huge challenge faced by those involved in Chinese environmental management, but this can be seen as an opportunity to improve environmental quality. This article introduces the strategies taken to improve solid waste management in China.     

Waste electrical and electronic equipment (WEEE) management in Korea: generation, collection, and recycling systems

In Korea, generation of waste electrical and electronic equipment (WEEE), or electronic waste (e-waste), has rapidly increased in recent years. The management of WEEE has become a major issue of concern for solid waste communities due to the volumes of waste being generated and the potential environmental impacts associated with the toxic chemicals found in most electronic devices. Special attention must be paid when dealing with WEEE because of toxic materials that it contains (e.g., heavy metals, polybrominated diphenyl ethers, phthalates, and polyvinyl chloride). If managed improperly, the disposal of WEEE can adversely affect the environment and human health. Environmental regulatory agencies; electronic equipment manufacturers, retailers, and recyclers; environmental nongovernmental organizations; and many others are much interested in updated statistics with regard to how much WEEE is generated, stored, recycled, and disposed of. In Korea, an extended producer responsibility policy was introduced in 2003 not only to reduce the amount of electronic products requiring disposal, but also to promote resource recovery from WEEE; the policy currently applies to a total of ten electrical and electronic product categories. This article presents an overview of the current recycling practices and management of electrical and electronic waste in Korea. Specifically, the generation rates, recycling systems and processes, and recent regulations of WEEE are discussed. We estimated that 1 263 000 refrigerators, 701 000 washing machines, 1 181 000 televisions, and 109 000 airconditioning units were retired and handled by the WEEE management system in 2006. More than 40% of the products were collected and recycled by producers. Four major producers’ recycling centers and other WEEE recycling facilities are currently in operation, and these process a large faction of WEEE for the recovery of valuable materials. Much attention should still be paid to pollution prevention and resource conservation with respect to WEEE. Several suggestions are made in order to deal with electronic waste management problems effectively and to prevent potential impacts.     

An evaluation of landfill disposal of asbestos-containing waste and geothermal residues within a risk-assessment framework

 The public perception of risks related to waste disposal facilities appears to reflect general societal anxieties and fears, which may not have a reasonable basis. A three-tier risk assessment study was therefore conducted to evaluate the landfill disposal of asbestos-containing waste (ACW) and geothermal residues. From the tier-1 analysis, the dominant asbestiform phase was identified as chrysotile, that is tightly bound in the matrix of calcite, while arsenic, cadmium, chromium, and lead were identified as the chemicals of potential concern associated with geothermal residues. From the tier-2 analysis, none of the possible exposure pathways associated with the landfill disposal of ACW was found to be potentially significant. On the other hand, there were potentially significant pathways associated with landfill disposal of geothermal residues because of the considerable potential pollution impact of leachate on soil and groundwater quality. From the tier-3 analysis, the health risk associated with landfill disposal of geothermal residues was found to be time-dependent, since the contributions to risk from water-dependent and water-independent pathways occur at different times, as indicated by RESRAD–Chem simulations. Component pathway analyses were performed to identify critical exposure pathways. The results from model sensitivity analysis have identified the input parameters that have the most influence on the time of peak risk, and the cancer risk associated with water-dependent and water-independent pathways. Received: July 9, 2002 / Accepted: October 17, 2002     

Recovery and recycling practices in municipal solid waste management in Lagos, Nigeria

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.     

Life cycle impact assessment of various waste conversion technologies

Advanced thermal treatment technologies utilizing pyrolysis or gasification, as well as a combined approach, are introduced as sustainable methods to treat wastes in Singapore. Eight different technologies are evaluated: pyrolysis–gasification of MSW; pyrolysis of MSW; thermal cracking gasification of granulated MSW; combined pyrolysis, gasification and oxidation of MSW; steam gasification of wood; circulating fluidized bed (CFB) gasification of organic wastes; gasification of RDF; and the gasification of tyres.Life cycle assessment is carried out to determine the environmental impacts of the various waste conversion systems including global warming potential, acidification potential, terrestrial eutrophication and ozone photochemical formation. The normalization and weighting results, calculated according to Singapore national emission inventories, showed that the two highest impacts are from thermal cracking gasification of granulated MSW and the gasification of RDF; and the least are from the steam gasification of wood and the pyrolysis–gasification of MSW.A simplified life cycle cost comparison showed that the two most costs-effective waste conversion systems are the CFB gasification of organic waste and the combined pyrolysis, gasification and oxidation of MSW. The least favorable – highest environmental impact as well as highest costs – are the thermal cracking gasification of granulated MSW and the gasification of tyres.     

A review of waste management practices and their impact on human health

This work reviews (i) the most recent information on waste arisings and waste disposal options in the world, in the European Union (EU), in Organisation for Economic Co-operation and Development (OEDC) countries, and in some developing countries (notably China) and (ii) the potential direct and indirect impact of waste management activities on health. Though the main focus is primarily on municipal solid waste (MSW), exposure to bioaerosols from composting facilities and to pathogens from sewage treatment plants are considered. The reported effects of radioactive waste are also briefly reviewed. Hundreds of epidemiological studies reported on the incidence of a wide range of possible illnesses on employees of waste facilities and on the resident population. The main conclusion of the overall assessment of the literature is that the evidence of adverse health outcomes for the general population living near landfill sites, incinerators, composting facilities and nuclear installations is usually insufficient and inconclusive. There is convincing evidence of a high risk of gastrointestinal problems associated with pathogens originating at sewage treatment plants. In order to improve the quality and usefulness of epidemiological studies applied to populations residing in areas where waste management facilities are located or planned, preference should be given to prospective cohort studies of sufficient statistical power, with access to direct human exposure measurements, and supported by data on health effect biomarkers and susceptibility biomarkers.     

Behavior of metals in ash melting and gasification-melting of municipal solid waste (MSW)

In this study, metal behavior in ash-melting and municipal solid waste (MSW) gasification-melting facilities were investigated. Eight ash-melting and three MSW gasification-melting facilities with a variety of melting processes and feedstocks were selected. From each facility, melting furnace fly ash (MFA) and molten slag were sampled, and feedstock of the ash-melting processes was also taken. For the ash melting process, the generation rate of MFA was well correlated with the ratio of incineration fly ash (IFA) in feedstock, and this was because MFA was formed mostly by mass transfer from IFA and a limited amount from bottom ash (BA). Distribution ratios of metal elements to MFA were generally determined by volatility of the metal element, but chlorine content in feedstock had a significant effect on Cu and a marginal effect on Pb. Distribution ratio of Zn to MFA was influenced by the oxidizing atmosphere in the furnace. High MFA generation and distribution ratio of non-volatile metals to MFA in gasification-melting facilities was probably caused by carry-over of fine particles to the air pollution control system due to large gas volume. Finally, dilution effect was shown to have a significant effect on metal concentration in MFA.     

Resolving public conflict in site selection process-a risk communication approach

In Japan, conflicts regarding the siting of waste disposal facilities occur frequently. In particular, siting of incinerators and landfills has become increasingly difficult because the public is highly concerned about the dioxin issues. Inefficient siting of waste disposal facilities causes several social problems, such as the shortage of waste treatment and disposal facilities, the rising of waste management costs and an increase in the consumption of resources. While dealing with a similar situation, the Chemical Society of Japan adopted a risk communication technique successfully. Hence, the pragmatic use of a risk communication technique is proposed to avoid conflicts and for a smooth information exchange to seek cooperation in waste management. In order to achieve this, a study was conducted to resolve conflicts between residents and the municipality for the selection of site for a solid waste treatment and disposal facility. This study aims to discuss the subject of risk communication for the waste disposal system in Japan. This study is performed through personal interviews and a questionnaire covering opposing parties in the town. As a result of the survey, a risk communication approach for a waste treatment and disposal system is presented in the paper addressing issues such as building of social trust, pragmatic use of the communication process, installation of credible information sources, and environmental education and awareness.     

Public opinion and awareness towards MSW and separate collection programmes: A sociological procedure for selecting areas and citizens with a low level of knowledge

The principal aim of this study was to define and apply a procedure based on a structured questionnaire survey useful to analyze the people’s environmental knowledge in order to select the areas and age groups with a low level of knowledge in a municipality (in Southern Italy) and, therefore, suggest a specific educational campaign for each. The detailed sampling procedure made it possible to carry out a meticulous statistical analysis of the results. The youngest and oldest people showed the lowest level of awareness for each district. A high level of education did not necessarily imply a high level of environmental awareness as well as a greater acceptance of MSW facilities. The satisfaction level of the recycling program was higher amongst the oldest age group. All the citizens in the several areas were unanimous in pointing out the presence of dirt in the street as the main shortcoming of the bring separate collection program. Only the youngest age group self-criticised, considering that they revealed a low level of participation to the separate collection program. While, the oldest people retaining them less influential, claimed that the citizens were not responsible for the failure of the separate collection program. The prevailing opinion of the sample was that people protested against the construction of waste facilities because they were not well-informed, with the most significant opinion of all the age subdivisions being that incineration is a hazardous treatment. The presence of criminal organizations was indicated as the main reason why the Campania Region suffers a serious solid waste emergency. While, the percentage of people pointing their finger at politicians increases with the average age of the respondents with there being a very strong correlation (r² = 0.9903).     

Bio-drying and size sorting of municipal solid waste with high water content for improving energy recovery

Bio-drying can enhance the sortability and heating value of municipal solid waste (MSW), consequently improving energy recovery. Bio-drying followed by size sorting was adopted for MSW with high water content to improve its combustibility and reduce potential environmental pollution during the follow-up incineration. The effects of bio-drying and waste particle size on heating values, acid gas and heavy metal emission potential were investigated. The results show that, the water content of MSW decreased from 73.0% to 48.3% after bio-drying, whereas its lower heating value (LHV) increased by 157%. The heavy metal concentrations increased by around 60% due to the loss of dry materials mainly resulting from biodegradation of food residues. The bio-dried waste fractions with particle size higher than 45 mm were mainly composed of plastics and papers, and were preferable for the production of refuse derived fuel (RDF) in view of higher LHV as well as lower heavy metal concentration and emission. However, due to the higher chlorine content and HCl emission potential, attention should be paid to acid gas and dioxin pollution control. Although LHVs of the waste fractions with size <45 mm increased by around 2× after bio-drying, they were still below the quality standards for RDF and much higher heavy metal pollution potential was observed. Different incineration strategies could be adopted for different particle size fractions of MSW, regarding to their combustibility and pollution property.     

Evaluation of the geotechnical properties of MSW in two Brazilian landfills

The characteristics of municipal solid waste (MSW) play a key role in many aspects of waste disposal facilities and landfills. Because most of a landfill is made up of MSW, the overall stability of the landfill slopes are governed by the strength parameters and physical properties of the MSW. These parameters are also important in interactions involving the waste body and the landfill structures: cover liner, leachate and gas collection systems. On the other hand, the composition of the waste, which affects the geotechnical behavior of the MSW, is dependent on a variety of factors such as climate, disposal technology, the culture and habits of the local community. It is therefore essential that the design and stability evaluations of landfills in each region be performed based on the local conditions and the geotechnical characteristic of the MSW. The Bandeirantes Landfill, BL, in São Paulo and the Metropolitan Center Landfill, MCL, in Salvador, are among the biggest landfills in Brazil. These two disposal facilities have been used for the development of research involving waste mechanics in recent years. Considerable work has been made in the laboratory and in the field to evaluate parameters such as water and organic contents, composition, permeability, and shear strength. This paper shows and analyzes the results of tests performed on these two landfills. The authors believe that these results could be a good reference for certain aspects and geotechnical properties of MSW materials in countries with similar conditions.     

An environmentally sustainable decision model for urban solid waste management

The aim of this work is to present the structure and the application of a decision support system (DSS) designed to help decision makers of a municipality in the development of incineration, disposal, treatment and recycling integrated programs. Specifically, within a MSW management system, several treatment plants and facilities can generally be found: separators, plants for production of refuse derived fuel (RDF), incinerators with energy recovery, plants for treatment of organic material, and sanitary landfills. The main goal of the DSS is to plan the MSW management, defining the refuse flows that have to be sent to recycling or to different treatment or disposal plants, and suggesting the optimal number, the kinds, and the localization of the plants that have to be active. The DSS is based on a decision model that requires the solution of a constrained non-linear optimization problem, where some decision variables are binary and other ones are continuous. The objective function takes into account all possible economic costs, whereas constraints arise from technical, normative, and environmental issues. Specifically, pollution and impacts, induced by the overall solid waste management system, are considered through the formalization of constraints on incineration emissions and on negative effects produced by disposal or other particular treatments.