Application of fuzzy DEMATEL to develop a cause and effect model of municipal solid waste management in Metro Manila

The municipal solid waste management (MSW) evaluation is usually evaluated in subjective and qualitative in nature described in linguistic information; it is very difficult for expert groups to express the preferences using exact numerical values. A MSW expert group is consulted in order to mirror how government officials might reach a cause-effect model regarding MSW management in Metro Manila. A critical issue regarding this is how the expert group can better evaluate the MSW management criteria in uncertainty. A cause and effect model development can help the processing of decision making problem. The Decision Making Trial and Evaluation Laboratory (DEMATEL) not only can convert the relations between cause and effect of criteria into a model but also can be used as a way to handle the inner dependences within a set of criteria. The post survey is further discussed and proved the validity result.     

Investigation of 15-year-old municipal solid waste deposit profiles by means of FTIR spectroscopy and thermal analysis

Five profiles of a 15-year-old bank containing over three weeks composted municipal solid waste were characterized by means of different parameters habitually applied in waste management (loss on ignition, total organic carbon, total nitrogen, NH(4)-N, pH), and in addition by humic acid determination, FTIR spectroscopy and thermal analysis. Stabilization processes are revealed by humic acid contents. Over the 15 year period organic matter had developed in various ways. Highest humic acid contents were found at 0.5 m below the surface. Below 1.0-1.5 m anaerobic conditions dominated causing a strong decline of humic acid concentrations. Despite similar contents of organic matter at 0.5 m and at 3.0 m organic matter quality differed. These differences were verified by infrared spectroscopic investigations and thermal analyses (differential scanning calorimetry DSC). The spectral pattern of 15-year-old profile samples (municipal solid waste including the biogenic fraction) was compared to current municipal solid waste and abandoned landfill materials. Current municipal solid waste samples comprised different degradation stages from fresh materials to stabilized waste, suitable for landfilling according to Austrian standards. Municipal solid waste originating from abandoned landfills closed in the seventies represented stable material. Principal component analysis was performed to detect similarities and differences. It is evident that the profile samples constitute a particular group in between municipal solid waste and abandoned landfill material. Some differences can be attributed to the divergent composition of municipal solid waste in the eighties when the organic fraction was not separated. Otherwise, landfill materials from the seventies with the same composition regarding the organic fraction were deposited together with construction waste. Heat flow curves (DSC profiles) of municipal solid waste, representing different decomposition stages, illustrate the development of enthalpies and reveal the status of the profile samples. It is evident that mechanical-biological pretreatment leads to a faster stabilization of waste organic matter.     

Assessment of potential impacts of municipal solid waste treatment alternatives by using life cycle approach: a case study in Vietnam

In Vietnam, most of municipal solid waste (MSW) is disposed of at open dumping and landfill sites, and the methane gas from waste is the un-ignorable source of greenhouse gas (GHG) emission. It is indispensable to explore the possibility for GHG mitigation in MSW management. The objective of this study was to estimate alternative waste treatment practices towards the GHG emission mitigation, energy consumption and generation, reduction of landfill volume, and various benefits for proposing the appropriate selection by scenario analyses for representative Vietnam’s cities. Impacts were calculated by utilizing life cycle assessment (LCA) method. A literature review survey on the current applicability of LCA database for assessing impacts from waste sector in developing countries, especially for Vietnam, was carried out. This study assessed the contribution of alternative solid waste treatment practices. The result showed that, except investment and operation costs, incineration with energy recovery seems the suitable alternative for treating waste from representative cities of Vietnam according to reduction of GHG emission and waste burden to landfill sites and energy recovery and generation. Besides, MSW composition was identified as an important factor directly influencing to impacts as well as other products and benefits of waste treatment alternatives. Reliable data on waste composition are indispensable for assessing to choose, improve, or plan the waste treatment practices towards sustainable development.     

Decision Analysis Methodology to Evaluate Integrated Solid Waste Management Alternatives

Value-focused thinking, a decision analysis technique, is used to produce a multiple-objective model that captures a site's municipal solid waste (MSW) management goals, objectives, and concerns in order to facilitate the evaluation of competing strategies. The model ranks competing MSW alternatives based on how well they meet the decision maker's strategic objective, a 20-year compliant MSW system. Sensitivity analysis is incorporated in the model to assess and illustrate the effects of changes in model objective weights and changes in model parameters. Overall, the model provides decision-makers with a decision tool to make a better decision when choosing a new MSW management strategy. The entire process is applied to a case study using Earekson Air Station, a remote U.S. Air Force installation.     

Land suitability assessment for wind power plant site selection using ANP-DEMATEL in a GIS environment: case study of Ardabil province,Iran

Wind energy is a renewable energy resource that has increased in usage in most countries. Site selection for the establishment of large wind turbines, called wind farms, like any other engineering project, requires basic information and careful planning. This study assessed the possibility of establishing wind farms in Ardabil province in northwestern Iran by using a combination of analytic network process (ANP) and decision making trial and evaluation laboratory (DEMATEL) methods in a geographical information system (GIS) environment. DEMATEL was used to determine the criteria relationships. The weights of the criteria were determined using ANP and the overlaying process was done on GIS. Using 13 information layers in three main criteria including environmental, technical and economical, the land suitability map was produced and reclassified into 5 equally scored divisions from least suitable to most suitable areas. The results showed that about 6.68 % of the area of Ardabil province is most suitable for establishment of wind turbines. Sensitivity analysis shows that significant portions of these most suitable zones coincide with suitable divisions of the input layers. The efficiency and accuracy of the hybrid model (ANP-DEMATEL) was evaluated and the results were compared to the ANP model. The sensitivity analysis, map classification, and factor weights for the two methods showed satisfactory results for the ANP-DEMATEL model in wind power plant site selection.     

Environmental monitoring of offshore drilling for petroleum exploration (MAPEM Project): shallow waters

This paper deals with the characteristics and composition of municipal solid waste (MSW) generated in Sangamner city. The composition of solid waste was studied by segregating it into different component, i.e., kitchen waste, paper, earth and fine material, slaughter house waste, leaves, metals, etc. These components were categorised into organic waste and inorganic waste. It was observed that Sangamner city produces around 61% organic waste, and the rest is inorganic waste. The characteristics of organic solid waste, i.e., pH, electrical conductivity, moisture content, organic carbon, nitrogen, phosphorus and potassium were evaluated. The analysis of organic content of MSW indicates that it is good source of nutrients for the agriculture sector whereas inorganic material can be used for landfill.     

An Interval-Parameter Fuzzy-Stochastic Programming Approach for Municipal Solid Waste Management and Planning

In this study, an integrated fuzzy-stochastic linear programming model is developed and applied to municipal solid waste management. Methods of chance-constrained programming and fuzzy linear programming are incorporated within a general interval-parameter mixed-integer linear programming framework. It improves upon the existing optimization methods with advantages in uncertainty reflection, data availability, and computational requirement. The model can be used for answering questions related to types, times and sites of solid waste management practices, with the objective of minimizing system costs over the planning horizon. The model can effectively reflect dynamic, interactive, and uncertain characteristics of municipal waste management systems. In its solution process, the model is transformed into two deterministic submodels, corresponding to upper and lower bounds of the desired objective function values under a given significance level, based on an interactive algorithm. Results of the method's application to a hypothetical case indicate that reasonable outputs have been obtained. It demonstrates the practical applicability of the proposed methodology.     

Application of processed organic municipal solid waste on agricultural land – a scenario analysis

Source separation, composting and anaerobic digestion, with associated land application, are increasingly being considered as alternative waste management strategies to landfilling and incineration of municipal solid waste (MSW). Environmental life cycle assessments are a useful tool in political decision-making about waste management strategies. However, due to the diversity of processed organic MSW and the situations in which it can be applied, the environmental impacts of land application are very hard to determine by experimental means. In the current study, we used the agroecosystem model Daisy to simulate a range of different scenarios representing different geographical areas, farm and soil types under Danish conditions and legislation. Generally, the application of processed organic MSW resulted in increased emissions compared with the corresponding standard scenarios, but with large differences between scenarios. Emission coefficients for nitrogen leaching to the groundwater ranged from 0.03 to 0.87, while those for nitrogen lost to surface waters through tile drains ranged from 0 to 0.30. Emission coefficients for N₂O formation ranged from 0.013 to 0.022 and for ammonia volatilization from 0.016 to 0.11. These estimates are within reasonable range of observed values under similar conditions. Furthermore, a sensitivity analysis showed that the estimates were not very sensitive to the mineralization dynamics of the processed organic MSW. The results show that agroecosystem models can be powerful tools to estimate the environmental impacts of land application of processed MSW under different conditions. Despite this, agroecosystem models have only been used to a very limited degree for this purpose.     

地理3G系统应用于城市固体废物管理的新模式

基于GPS、GPRS、GIS地理3G综合技术,设计城市固体废物综合监管系统,实现对固体废物从收集到再利用全过程的监督管理。该系统由申报信息系统、地面控制系统、处置保障系统、综合分析系统、应急指挥系统和线上“淘宝”系统组成,在固体废物收集站点采集的数据上传至综合分析系统,经分析与匹配后相关信息发布在线上“淘宝”交易平台,平台为买卖双方提供资源配置方案,也为管理部门的宏观调控提供数据支撑。     

Deficit analysis: service capacity assessment and planning in developing countries – case study in the Philippines

Current demand analysis methods do not formally cover the case of chronic deficits in quantity or quality of water and sanitation services. These services include drinking water supply (DWS), wastewater and sewage treatment (WST), and municipal solid waste management (MSW). Formal analysis of this case would, at minimum, define the deficit state and evaluate appropriate options for reducing it. This paper proposes for a formal analytical model for municipal sanitation systems (MSS) that operate with deficits in at least one of the constituent services of DWS, WST, or MSW. The model introduces definitions and notation for describing the deficit state for conducting demand analysis on municipal sanitation systems. This model of demand analysis for systems with chronic deficits will hereinafter be referred to as deficit analysis. A case study for Bacoor, Philippines is presented as an example.     

Municipal solid waste management in Thailand and disposal emission inventory

The increasing municipal solid waste (MSW) generation along with the high fraction of organic waste and a common disposal of open dumping is the current scenario in many areas in Thailand. As a response to this problem, the country’s Pollution Control Department (PCD) aims to reduce the MSW generation rate to less than 1 kg/capita/day, increase the collection efficiency, and improve the recovery of recyclables. For many years, more than 60% of the solid waste disposal system in Thailand has been carried out by open dumping. According to the survey conducted by this study, in 2004 there were 425 disposal sites (95 landfills; 330 open dumps) in Thailand and an estimated methane emission of 115.4 Gg/year was generated based on this practice. It has been estimated that the anticipated methane emission in Thailand will rise from 115.4 Gg/year to 118.5 Gg/year if the largest open dumpsites in provinces with no existing landfill are upgraded to sanitary landfill; and it will increase to 193.5 Gg/year if the existing sanitary landfill is upgraded to integrated waste management facilities. Moreover, Bangkok metropolitan have the highest methane emission (54.83 Gg/year) among all the regions in Thailand. The methane emission forecast of 339 Gg/year by 2020 (based on LandGEM methodology) provides a stimulus to create a comprehensive plan to capture and utilize methane as an energy source.     

四川省城市生活垃圾的组成及特性

对四川省典型城市生活垃圾的组成、元素分析及热值等实验结果进行分析,结果表明:典型城市生活垃圾具有厨余含量高(57.4%～66.1%)、渣土含量少(1.9%～11.7%)的特点;四川省城市生活垃圾热值介于4 200～5 500 kJ/kg之间,且大部分处在4 800～5 500 kJ/kg之间;攀枝花、绵阳和成都市金牛区城市生活垃圾热值较高,适合采用焚烧法,内江和遂宁的城市生活垃圾热值偏低,宜采用填埋的方法。     

Geospatial strategy for sustainable management of municipal solid waste for growing urban environment

This paper presents the implementation of a Geospatial approach for improving the Municipal Solid Waste (MSW) disposal suitability site assessment in growing urban environment. The increasing trend of population growth and the absolute amounts of waste disposed of worldwide have increased substantially reflecting changes in consumption patterns, consequently worldwide. MSW is now a bigger problem than ever. Despite an increase in alternative techniques for disposing of waste, land-filling remains the primary means. In this context, the pressures and requirements placed on decision makers dealing with land-filling by government and society have increased, as they now have to make decisions taking into considerations environmental safety and economic practicality. The waste disposed by the municipal corporation in the Bhagalpur City (India) is thought to be different from the landfill waste where clearly scientific criterion for locating suitable disposal sites does not seem to exist. The location of disposal sites of Bhagalpur City represents the unconsciousness about the environmental and public health hazards arising from disposing of waste in improper location. Concerning about urban environment and health aspects of people, a good method of waste management and appropriate technologies needed for urban area of Bhagalpur city to improve this trend using Multi Criteria Geographical Information System and Remote Sensing for selection of suitable disposal sites. The purpose of GIS was to perform process to part restricted to highly suitable land followed by using chosen criteria. GIS modeling with overlay operation has been used to find the suitability site for MSW.     

Monitoring quantity and characteristics of municipal solid waste in Dhaka City

A reliable estimate of the quantity of solid waste generation in the city is very important for proper solid waste planning and management. However, reported estimates of solid waste generation vary widely and lead to questionability. The reported values have been derived on the assumption of demography, standard rate of waste generation by households, density values, number of trucks engaged for waste transportation and monitoring of truck movement at dump sites, etc. This diverse nature of the available data and the question of accuracy necessitate a rigorous study that has tried to document the waste quantity in the recently formulated master plan of Dhaka City. The socio-economic parameters, behavioral characteristics, generation sources, seasonality, and per capita growth rate are considered in estimating the waste quantity along with its future projections. The findings from the estimation of waste quantities state that seasonal differences in the municipal solid waste stream are not substantial. The most seasonably variable material in the municipal solid waste stream is food waste. Residential waste is relatively homogeneous. Although there are some differences in waste generation depending on demographic and other local factors, most households dispose of essentially similar types of wastes. Variation occurs in waste composition dependent upon income levels and category of sources. Variation also occurs based upon the extent of source reduction and recycling opportunities. As opportunities exist to recycle wastes, the recycling facilities might have to grow at a similar pace to the generation of waste. Physical and chemical characteristics of solid waste are important to implement the waste disposal and management plan for the selection of resource and energy recovery potentials. A number of studies have been conducted to determine the composition of wastes including moisture content and calorific value. The data show that the moisture content in city waste is significantly higher and the calorific value is much lower, which determines the viability of composting or anaerobic digestions rather than waste combustion.     

Monitoring of flow field based on stable isotope geochemical characteristics in deep groundwater

As circumstances of operating and maintenance activities for landfilling and composting in Tehran metropolis differ from those of cities in developed countries, it was concluded to have an environmental impact comparison between the current solid waste management (MSW) strategies: (1) landfill, and (2) composting plus landfill. Life cycle assessment (LCA) was used to compare these scenarios for MSW in Tehran, Iran. The Eco-Indicator 99 is applied as an impact assessment method considering surplus energy, climate change, acidification, respiratory effect, carcinogenesis, ecotoxicity and ozone layer depletion points of aspects. One ton of municipal solid waste of Tehran was selected as the functional unit. According to the comparisons, the composting plus landfill scenario causes less damage to human health in comparison to landfill scenario. However, its damages to both mineral and fossil resources as well as ecosystem quality are higher than the landfill scenario. Thus, the composting plus landfill scenario had a higher environmental impact than landfill scenario. However, an integrated waste management will ultimately be the most efficient approach in terms of both environmental and economic benefits. In this paper, a cost evaluation shows that the unit cost per ton of waste for the scenarios is 15.28 and 26.40 US$, respectively. Results show landfill scenario as the preferable option both in environmental and economic aspects for Tehran in the current situation.     

An Improved Rating System for Assessing Surface Water Contamination Potential from MSW Landfills

Leachate emission from uncontrolled municipal solid waste landfills (referred to as waste sites in the present study) is a major threat to the environment and living beings in its vicinity. Surface water contamination potential resulting from leachate may be used as one of the criteria for prioritization of sites for remediation purposes. The existing hazard rating systems that prioritize waste sites considering surface water contamination potential as one of the criteria are mainly suited for the developed countries where these were developed initially. In developing countries like India, the set of conditions differ from those in developed countries, and therefore the existing systems may not be suitable for developing countries. Thus in the present study, an improved system is proposed to assess surface water contamination potential from MSW sites. The system is based on the concept of Source, Pathway and Receptor. The proposed system employs parameters derived from the review of existing rating systems and selects their best and worst values based on literature review, design standards and field conditions. The importance weights of the system parameters have been decided based on expert judgment using Delphi technique. Sensitivity analysis of the system shows that the improved system is more sensitive than the existing systems for the site conditions encountered in developing countries. Monte Carlo analysis of the proposed system confirms the spread of the scores obtained from the system over the full scale of 0–1000. The improved system is compared with existing systems by applying it to waste sites from metropolitan cities of India and performing clustering analysis on the rating scores. The clustering analysis shows that the rating scores from the improved system are less clustered as compared to the scores from the existing systems. This demonstrates that the improved system makes a better tool to distinctly prioritize the waste sites for remediation purpose.     

Selection of MSW landfill site for Konya, Turkey using GIS and multi-criteria evaluation

Landfill is a common solution for the final disposal of municipal solid waste (MSW) in Turkey. Landfill siting is an extremely difficult task to accomplish because the site selection process depends on different factors and regulations. To ensure that an appropriate site is chosen, a systematic process should be developed and followed. Unsuccessful landfill siting is typically the result of strong public opposition. In this study, candidate sites for an appropriate landfill area in Cumra County of Konya City are determined by using the integration of geographic information systems (GIS) and multi-criteria evaluation (MCE). ArcGIS 9.0 software and its extensions were used as the GIS tool since it is able to perform suitability analysis using MCE analysis. To identify appropriate landfill areas in the Cumra district, eight input map layers including proximity to municipal and local wells and irrigational canals, distance from transportation routes and rails, distance from archaeological sites, distance from urban areas, land use/land cover, and land slope are used in constraint mapping. A final map was generated which identifies regions showing suitability for the location of the landfill site. According to the map, 6.8% of the study area is most suitable, 15.7% is suitable, 10.4% is moderately suitable, 25.8% is poorly suitable, and 41.3% is unsuitable. At the end of the analyses, three candidate sites are determined. The selection of the final MSW landfill site, however, requires further field research.     

Residents’ concerns and attitudes toward a municipal solid waste landfill: integrating a questionnaire survey and GIS techniques

The ever-growing industry of municipal solid waste (MSW) disposal appeals to the growing need for disposal facilities, and MSW treatment facilities are increasingly an environmental and public health concern. Residents living near MSW management facilities are confronted with various risk perceptions, especially odour. In this study, in an effort to assist responsible decision-makers in better planning and managing such a project, a structured questionnaire was designed and distributed to assess the nearby residents’ concerns and attitudes surrounding the Laogang Landfill in Shanghai. Geographic information system techniques and relevance analysis were employed to conduct the spatial analysis of physical perceptions, especially odour annoyance. The findings of the research indicate that a significant percentage of the responding sample was aware of the negative impacts of landfills on the environment and public health, and residents in close proximity preferred to live farther from the landfill. The results from the spatial analysis demonstrated a definite degree of correlation between odour annoyance and distance to the facility and proved that the benefits of the socially disadvantaged have been neglected. The research findings also direct attention to the important role of public participation, information disclosure, transparency in management, and mutual communication to avoid conflicts and build social trust.     

The composition, trend and impact of urban solid waste in Beijing

This paper provides an overview of the trend of generation, composition, and management of municipal solid waste, and estimates the carbon emissions arising from municipal solid waste management in Beijing. The correlation analysis conducted shows that the generation of municipal solid waste in Beijing has been growing steadily, showing high correlations (r > 0.9) to the total GDP, per capita income, and the population. Food waste showed an increasing trend since 1990. Compared with the results of an investigation in 1990, ash and woodchips content in 2003 declined from 56% to 17%, while the percentage of paper and plastic increased from 10% to 29% over the same period. The calorific value of the municipal waste also increased, from 2,686 kJ/kg in 1990 to 4,667 kJ/kg in 2003, indicating that the waste is suitable for incineration. Currently, the source separation ratio of municipal waste is approximately 15%. About 94% of all the collected solid waste goes to the landfill while 4% is composted and 2% is incinerated. A moderate garbage collection fee is applied to both permanent and temporary residents in Beijing, but the willingness to pay for solid waste collection and treatment is still low. Under current treatment mode, the total amounts of carbon emission from waste disposal sites and incineration increased with the increase of municipal solid waste, from 29.8 Gg in 1990 to 84.5 Gg in 2003, including 83.3 Gg of CH₄ and 22.0 Gg of CO₂. The data availability and methodological challenges in monitoring the quantity and characteristics of municipal solid waste are discussed.     

A Time-Dependent System for Evaluating Groundwater Contamination Hazard Rating of Municipal Solid Waste Dumps

In developing countries, several old municipal solid waste dumps (unlined landfills) exist adjacent to large cities, releasing contaminants to the underlying aquifer, thus posing the hazard of groundwater contamination. These uncontrolled waste dumps need to be prioritized in terms of the groundwater contamination hazard posed by them, so that necessary control and remedial measures can be undertaken in a phased manner. This paper presents a time-dependent system for evaluating groundwater contamination hazard rating of municipal solid waste dumps. The system is based on source–pathway–receptor relationships and evaluates the relative value of hazard posed by a site over its entire leaching life, on a scale of 0–1,000. The system parameters have been selected based on literature and expert opinions. The Delphi technique is used to derive the relative importance weights of the system parameters. The proposed system is compared with six selected existing hazard rating systems. The comparison, made by way of score range analysis, shows that the proposed system exhibits a much wider range of hazard scores for various scenarios of site conditions, and hence the proposed system is more sensitive to varied site conditions. The application of different systems to six municipal solid waste dumps located in four cities of India shows that, whereas the existing systems individually produce clustered scores and return the same rank to more than one site, the proposed system produces significantly varying scores and return different ranks to different sites. This demonstrates that the proposed system improves decision making and makes a better basis for prioritization of municipal solid waste dumps for adopting control and remedial measures.