Current Municipal Solid Waste Management System Research Articles

Use of life cycle assessment for estimating impacts of waste-to-energy technologies in solid waste management systems: the case of Buenos Aires, Argentina.

Analysing municipal solid waste (MSW) management scenarios is relevant for planning future policies and actions toward a circular economy. Life cycle assessment (LCA) is appropriate for evaluating technologies of MSW treatment and their environmental impacts. However, in developing countries, advanced assessments are difficult to introduce due to the lack of technical knowledge, data and financial support. This research aims to assess the main potentialities of the introduction of waste-to-energy (WtE) systems in a developing Argentinean urban area considering the existing regulations about MSW recycling goals. The study was conducted with WRATE software and the proposed scenarios were current management, grate incineration of raw MSW and incineration of solid recovered fuel (SRF). In addition, a sensitivity analysis on the energy matrix was included. It was found that the production of SRF allows increasing the energy generation from waste by 200% and reducing the environmental impact of about 10% regarding the current MSW management system. Acidification Potential and Abiotic Depletion Potential were sensitive to changes in electricity mix. Results showed that if MSW reduction goals are achieved, changes in MSW composition will affect the performance of WtE plants and, in some cases, they will be not technically feasible. The outcomes of this study can be of interest for developing countries stakeholders and practitioners interested in LCA and sustainable MSW management.

Citizens’ willingness to pay for adaptive municipal solid waste management services in Jakarta, Indonesia

The capability of municipal solid waste management (MSWM) services and the system's sustainability are significant challenge in developing cities like Jakarta. MSWM provides a comprehensive, adaptive capacity framework for addressing problems in resource-constrained developing nations where poor assets, flexibility, social organization, learning, and agency have no adaptive means of regaining them. This paper aim to conduct an evaluation framework under adaptive MSWM, estimates citizens’ preferences heterogeneity and, evaluates willingness-to-pay (WTP) under hypothetical scenarios of future adaptive MSWM retribution. The findings indicate that adaptive MSWM services substantially impact the decision to expand their environment. In addition, citizens who supported the adaptive MSWM services tended to have a higher income than the minimum wage, live outside of slums, are older than 39 years, and are aware of climate change and the current MSWM system and infrastructure. The findings imply that policymakers must enhance citizen MSWM awareness of climate change and infrastructure used to dealing with adaptability strategies. Finally, we establish three adaptive MSWM scenario for sustainable services with the optimization of the MSWM system and infrastructure, community-based MSWM, and smart MSWM system and infrastructure.

Modular incinerator with pre-treatment plant for municipal solid waste treatment in the super-priority tourism destination of Labuan Bajo Indonesia

One of the competitiveness parameters of tourist destinations is the cleanliness index. Labuan Bajo as a super-priority tourist destination has a very serious municipal solid waste (MSW) problem. Waste generation in Labuan Bajo and Komodo National Park in 2020 reached 14.06 tons/day and is projected to be 15.51 tons/day in 2023. The main sources of MSW come from settlements, hotels, traditional markets, and seaports. The current MSW management system is that waste is collected from the source and then transported to a temporary storage tank to be transported by truck to the Warloka landfill. This system poses a threat in the form of shortening the service life of the landfill. Management through recycling is still a very low percentage because the recycling ecosystem has not yet developed. One alternative for MSW management that is currently being carried out by the central government in Labuan Bajo is to implement a modular incinerator. This paper describes the process of designing and operating a test incinerator with a combustion capacity of 20 tons/day consisting of 2 lines each with a capacity of 10 tons/day. The incinerator is equipped with a pre-treatment plant consisting of a sorting conveyor, thermal dryer, and storage conveyor. The incinerator furnace consists of two chambers and each is equipped with a burner. This furnace is designed to be able to burn waste with a calorific value of 1300 kcal/kg with a maximum moisture content (MC) of 60%. The test results show that the temperature in the primary chamber can reach a minimum of 800°C and a maximum of 1000°C in the secondary chamber. The burning rate has obtained a maximum of 527 kg/h which means it has passed the initial design of 417 kg/h. To meet emission-quality standards, exhaust gas is processed through flue gas treatment consisting of a cyclone, quencher scrubber, and chimney. Emissions measured by CEMS include parameters of particulates, CO, SO2, and NOx, all of which are below the national emission-quality standards. The heat generated from partial combustion will be channeled to the thermal dryer to reduce MC so that it can reach 40%. The results of burning waste with this incinerator produce fly ash and bottom ash about 4% of the weight of the input waste.

An Integrated Environmental Assessment of MSW Management in a Large City of a Developing Country: Taking the First Steps Towards a Circular Economy Model

Most of the municipal solid waste (MSW) in developing countries ends up in landfills. For example, more than 95% of the MSW generated in Latin America is disposed of in some type of landfill. Factors such as high organic compositions, low recycling rates and poor control over the disposal sites greatly increase the environmental impacts associated with MSW management in this region, resulting in increased emissions of greenhouse gases (GHGs) and runoff of leachates. Therefore, local governments in Latin America are making efforts to transition to more “circular” management models for MSW. This is the case in the Guadalajara Metropolitan Area (GMA), the third most populous city in Mexico, where the implementation of the following two mechanical biological treatment (MBT) alternatives are being considered: 1) a high-capacity mechanical sorting facility with no biological treatment and 2) a medium-capacity mechanical sorting facility coupled with a composting process. Thus, the aim of the present study was to assess the environmental performance of the current MSW management system (baseline) as compared to the two potential MBT alternatives through life cycle assessment (LCA) and sensitivity analyses. Furthermore, by using a SWOT analysis, this study aimed to provide insights into the main economical, sociocultural, legal, political and technological/infrastructure challenges that need to be overcome in the GMA, as well as other cities in developing countries, in order to transition to circular MSW management models. An assessment of global warming potential (measured in Gg CO2-eq/year) indicated that the current MSW management system (baseline) results in the emission of 111.21 Gg CO2-eq/year, while the two potential alternative scenarios displayed a net emissions reduction of 24 and 34%, respectively, due to material recycling and the substitution of petroleum coke with refuse-derived fuel (RDF) in cement kilns. When evaluating abiotic resource depletion (measured in Gg Sb-eq/year), the potential alternative scenarios both outperformed the baseline with savings increases between 3,380 and 3,501%. This result is largely attributed to the decrease in fossil fuel consumption (due to the substitution of petroleum coke with RDF), which provides a potential reduction of 5.62 Gg Sb-eq/year. The sensitivity analysis revealed that several key parameters, such as the fraction of food and plastic wastes in the MSW, can alter the scenario rankings. Recycling of the recovered materials and treatment of the organic fraction were found to be key strategies for a reduction in direct environmental impacts. Additionally, better management of waste picker activities, standardization of landfill operations and enhancement of material separation and selective collection must be addressed prior to the introduction of new treatment technologies. The results of the study herein can assist in the formation of policies to improve the feasibility of MBT implementation and drive the first steps towards a circular economy model in the GMA, as well as other cities within Latin American and Caribbean regions with similar characteristics.

The Future of Flash Graphene for the Sustainable Management of Solid Waste.

Graphene research has steadily increased, and its commercialization in many applications is becoming a reality because of its superior physicochemical properties and advances in synthesis techniques. However, bulk-scale production of graphene still requires large amounts of solvents, electrochemical treatment, or sonication. Recently, a method was discovered to convert bulk quantities of carbonaceous materials to graphene using flash Joule heating (FJH) and, so named, flash graphene (FG). This method can be used to turn various solid wastes containing the prerequisite element carbon into FG. Globally, more than 2 billion tons of municipal solid waste (MSW) are generated every year and, in many municipalities, are becoming unmanageable. The most commonly used waste management methods include recycling, composting, anaerobic digestion, incineration, gasification, pyrolysis, and landfill disposal. However, around 70% of global waste ends up in landfills or open dumps, while the rest is recycled, composted, or incinerated. Even the various waste valorization techniques, such as pyrolysis and gasification, produce some waste residues that have their ultimate destination in landfills. Thus, technologies that can minimize waste volume or convert waste into valuable products are required. The thermal treatment process of FJH for FG production provides both waste volume reduction and valorization in the form of FG. In this Perspective, we provide an overview of FJH and its possible applications in various types of waste conversion/valorization. We describe the typical current MSW management system as well as the potential for creating FG at various stages and propose a schematic plan for the incorporation of FG in MSW management. We also analyze the strengths, weaknesses, opportunities, and threats of MSW as an FG precursor in terms of technical, economic, environmental, and social sustainability. This valuable waste valorization and management strategy can help achieve near-zero waste and an economy-boosting MSW management system.

Assessment of municipal solid waste management system in Lae City, Papua New Guinea in the context of sustainable development.

Lae City (LC) of Morobe Province is the second-largest city in Papua New Guinea. Due to the abundant natural resources it inherits, the resultant urbanization has led to an influx of the human population. This increase in population as a result of industrialization has led to increased municipal solid waste (MSW) accumulation. To address this exigent issue, which affects the nation’s carbon footprint, it is imperative to review socio-economic and geographic factors to establish a feasible approach for managing MSW efficiently and sustainably. In the quest to achieve the same, the present assessment focuses on the 3 core waste management hierarchy systems to support sustainable development for LC by reviewing existing opportunities and challenges associated with the current MSW management system and the associated policies. The result shows that as a sustainable approach to MSW management of LC, a zero-waste campaign for resource recovery engaging all stakeholders can be implemented since the organic content of MSW generated in LC is as high as 70%. Moreover, the dumping of MSW at the dedicated dumpsite site can be minimized if policies are strengthened and the proposed waste avoidance pathway is implemented strictly. In addition to this, to avoid the contamination of groundwater and recovery of methane, the use of the Fukuoka approach in the existing landfills has been suggested to capture leachate without any huge expenditure.Graphic abstract

The impact of incineration phase-out on municipal solid waste landfilling and life cycle environmental performance: Case study of Madrid, Spain

Reducing the amount of municipal solid waste (MSW) fed to incineration while enhancing source separation and biological treatments is being considered a mean to protect the environment and human health and promote recycling. However, such a strategy can compromises the landfill reduction targets while the associated environmental benefits remain so far unexplored and, in any case, any potential benefit should be evaluated for specific situations. In this study we applied material flow analysis (MFA) and life cycle assessment (LCA) to quantitatively evaluate the potential impact of phasing-out incineration in Madrid, Spain. The current MSW management system was assessed against future scenarios that describe the elimination of incineration as well as the increase of source separation, recycling, composting, and anaerobic digestion. The results revealed that incineration phase-out jeopardizes landfill reduction. However, phasing-out incineration can reduce the impact on acidification, terrestrial and marine eutrophication, photochemical ozone formation, human toxicity cancer effects, and ecotoxicity. The climate impact ranges from irrelevant to largely beneficial depending on how the biogenic carbon is considered. The transition towards a renewable electricity mix and the increase in source separation of biodegradable waste seriously compromise the climate benefits of incineration over landfilling. Overall, actions are required in order to align incineration phase-out with the landfill reduction objective, namely upgrading material recovery facilities to reduce rejects and seeking alternative pathways for the rejects that will always exist.

Application of life cycle assessment for municipal solid waste management options in Hohhot, People's Republic of China.

With increasing population and urbanization levels in the People's Republic of China, environmental problems related to the management of municipal solid waste (MSW) are inevitable. This study aimed to determine the environmental impact of the current MSW management system in Hohhot City and to establish an optimum future strategy for it by applying life cycle assessment (LCA) methodology. Four scenarios were compared using the CML-IA impact characterization method, which took into account their potential contribution to global warming, ozone depletion, human toxicity, photochemical ozone creation, acidification, and eutrophication potentials. The system boundaries included the collection and recycling, transfer and transportation of MSW, and its disposal by incineration, landfilling, and carbon dioxide (CO2) capture methods. The results showed that the scenario involving landfill and incineration in a ratio of 1:5 was the optimal waste management option; however, increasing the proportion of waste incinerated led to a significant increase in global warming potential. Additional technologies are thus required to overcome this problem, and it was found that the use of CO2 capture technology resulted in a 30% reduction in the total environmental impact potential. This study's results indicate that LCA is a valuable and practical tool to support decision-making that can be used to suggest problematic areas in current waste management strategies and to determine an optimal alternative to the solid waste management option.

Life-cycle assessment of municipal solid waste management options: A case study of refuse derived fuel production in the city of Brasilia, Brazil

In Brazil, municipal solid waste (MSW) is mainly treated by landfilling. The underutilization of solid waste resources, from the viewpoint of their heating value, contributes to increasing greenhouse gas (GHG) emissions and abiotic resources depletion. MSW as a resource, however, is capable of a coupe with the existing demand of the local cement industry as refuse-derived fuel (RDF). This paper analyzes the application of life-cycle assessment as the basis for improved MSW management in the Brasilia, the capital of Brazil. This study compared four scenarios of MSW management, in which three of them are characterized as an expansion of the ongoing practice by incorporating RDF production while another considers only the landfilling of solid waste. The results indicated that the current MSW management system contributes 267.44 Gg CO2-eq/year to GHG emissions, and the study showed that scenarios based on RDF production imply an increase in energy demand, with higher total GHG emissions, compared to the current management practice. However, gains are archived in environmental terms when the avoided emissions resulting from the substitution of fossil fuels are included in the analysis. The production and use of RDF outperformed the conventional systems by providing emission reductions of 2% to about 23%. Besides, this implies that the implementation of RDF oriented management could significantly reduce the impact on current disposal capacity at the local landfill site. From the perspective of impact related to abiotic resource depletion, it has been found that recycling and composting in the current scenario produces a reduction of 0.12 Gg Sb-eq/year. It constitutes a minimal fraction compared to the reduction in fossil fuel when considering the avoided coke extraction, that provides reductions from 3.63 to 13.73 Gg Sb-eq/year. It was concluded that the environmental advantages of RDF base scenarios in this context arise when the assessment is expanded to include the reduction of GHG indirect emissions and the use of resources.

Prognóstico da gestão dos resíduos sólidos urbanos de uma cidade de médio porte: estimativa de impactos ambientais

A busca por um sistema de gestão de Resíduos Sólidos Urbanos (RSU) sustentável é um desafio para gestores municipais. Para isso, é necessário inicialmente entender o atual sistema de gestão e seus futuros resultados. Este trabalho teve o objetivo de realizar o prognóstico do atual sistema de gestão de RSU do município de Juazeiro do Norte no Ceará. O estudo é quantitativo e utilizou métodos quantitativos de modelagem para estimar, em um período de 20 anos (2016 a 2035), impactos ambientais de ocupação de área por aterro e de emissão de gás metano (CH4) e de gás carbônico (CO2). Os resultados apontam que, caso nada seja feito, os RSU coletados e enterrados no aterro do município, entre 2016 e 2035, ocuparão uma área equivalente a 20 campos de futebol (147.140 m2) e emitirão aproximadamente 153.300 e 420.600 toneladas de CH4 e CO2, respectivamente, que se estenderão por 40 anos. Os resultados dessa pesquisa destacam um cenário futuro preocupante que pode e deve ser mitigado através do planejamento e implementação de alternativas de mudanças do atual sistema de gestão de RSU da região.

Selection of the Best Solid waste Management Yaounde using an Analytical Hierarchy Process

Municipal solid waste (MSW) management is one of the global challenges facing the world today in order to achieve development goals. This paper aims to structure MSW management problems into hierarchy to assist in decision making process in order to select the most appropriate MSW management strategy in Yaounde. The tool used is the Analytical Hierarchy Process (AHP), one of the multi criteria decision making techniques. From the synthesis of the decision/policy makers’ judgements, the criteria “sustainable development” and “waste service quality” are the priority objectives that must be applied to MSW management system in Yaounde; and the alternatives “pre-collection” and “selective collection” are the suitable actions to integrate into the current MSW management system in Yaounde.

Assessing the social performance of municipal solid waste management systems in developing countries: Proposal of indicators and a case study

This article analyses the social performance of municipal solid waste (MSW) management systems in developing countries. For this purpose, a set of social impact categories, indicators and metrics capable of assessing the socio-economic and labour conditions of the different stakeholders involved in the life cycle of a MSW management system is proposed. Specifically, 12 social impact categories and 22 indicators with their corresponding metrics have been suggested. The application of the proposed indicators is illustrated by a case study in the districts of João Pessoa (Brazil), where selective MSW collection has been implemented with the collaboration of previous informal waste pickers, who have been reorganised into associations or cooperatives of collectors of recyclable materials (formal sector). The results suggest that despite the improvements made in the last decade in the current MSW management system of João Pessoa, there is still plenty of room for improvement. The social impact category with better performance is related to a “value chain actors relationship”, while “equal opportunities/discrimination” and “working benefits” show a high improvement potential.

Steps towards more environmentally sustainable municipal solid waste management – A life cycle assessment study of São Paulo, Brazil

Abstract Landfill disposal has thus far been the predominant treatment method for municipal solid waste (MSW) throughout Brazil, including Sao Paulo city. Environmentally sustainable development of MSW management in Sao Paulo necessitates a stepwise reduction of landfilling. However, ever increasing MSW generation poses the challenge of managing increasing MSW volumes while simultaneously modernizing the MSW management system. In this study, the environmental impacts of the current MSW management system and future alternatives in the city were assessed by means of life cycle assessment (LCA) to determine a pathway towards more environmentally sustainable MSW management. The assessed impact categories were global warming, acidification and eutrophication potentials. Potential future alternatives included the stepwise reduction of landfilling by the introduction of composting, anaerobic digestion and mechanical-biological treatment (MBT). The results of the study indicated that the environmental impacts of MSW management in Sao Paulo can be most effectively diminished by anaerobic digestion of source separated organic waste and MBT of MSW, on condition that the produced refuse-derived fuel (RDF) is utilized in cement production as a substitute for coal. The other utilization option for RDF, incineration, would increase the environmental impacts of MSW management due to the low amount of avoided emissions resulting from electricity substitution since average electricity production in Brazil is dominated by hydropower. Sensitivity analyses indicated, however, that the environmental impacts of incineration might decrease with different modeling assumptions, e.g. the modeling assumption regarding the kind of electricity production substituted by electricity production from MSW. Nevertheless, the main findings of the study remained the same and they are in line with the previous literature.

Assessing the public perception of islanders regarding the implementation of new technologies to optimize the municipal solid waste management system: A Mediterranean case study

One of the most important contemporary challenges for small islands is to make more sustainable human activities as the management of municipal solid waste (MSW). The recent EGADI project involved the realization of two pilot project actions in a small Mediterranean island of Southern Italy (Island of Favignana) with the goal to adapt the current MSW management system to the logic of the 3Rs approach (reduce, reuse & recycle). The actions concerned the installation of a water kiosk to reduce plastic waste production and a community composter to recover material from the organic fraction of MSW. Additionally, non-structural actions as a communication plan and an environmental education campaign were implemented with the intent of increasing public awareness on the addressed topics. In this context, the study was aimed to investigate the public perception and knowledge of islanders with reference to the two pilot actions before and after the implementation of such activities so as to provide guidance for optimizing the MSW management system of the island. A structured questionnaire was implemented and administered to the students of a secondary school and their parents before and after the implementation of the planned actions. The obtained data were processed by using descriptive statistics and Multiple Correspondent Analysis (MCA) in order to achieve a global view on the level of knowledge and public perception as well as to establish as a whole, the rate of satisfaction and the goodness of the project actions. The feedbacks on the implemented actions were critically discussed highlighting both positive and negative aspects. Some drawbacks were to be connected to the adopted communicative plan which resulted to be not so effective in reaching the target since its random character. Islanders perceived positively the new technologies implemented. The water kiosk was perceived positively if it only serves residents. Furthermore, islanders positively perceived the kerbside separate collection preferring at the same time the community composting as strategy for the management of the organic fraction, at least in the most densely populated areas. The social assessment that was conducted during the investigation provided guidance of the optimum MSW management system of the island.

Environmental performance of municipal solid waste strategies based on LCA method: a case study of Macau

Increasing public attention has been brought to bear on the environmental impacts of municipal solid waste (MSW) management in Macau, due to the continually increasing amount of MSW being generated and the limited space and capacity of waste treatment facilities. This study evaluates the current and potential patterns of MSW management with regard to environmental impacts in Macau, using the life cycle assessment (LCA) method. We also assess the baseline scenario, reflecting the existing MSW management system, as well as five other scenarios, exploring waste treatment innovations, to quantitatively predict potential environmental impact mitigation for Macau. Additionally, a sensitivity analysis is used to investigate the influence of the different assessment methods and recycling rates of valuable resources in the source separation process. The results show that the current management system of MSW in Macau can treat and dispose of the MSW well, and at the same time can generate some environmental benefits. Compared with Scenario 0 (the current MSW management system), Scenario 4 (source separation and incineration) shows the highest potential to increase the environmental benefits. Scenario 5 (integrated waste management) is also a good option, with higher benefits (85.96%) than Scenario 0. The analysis shows that, in each scenario (except Scenario 1, the past process of landfill only), the waste treatment processes, including source separation and incineration, dominate the environmental impacts; while processes such as collection and transportation, composting, and landfill, have a relatively small influence. The sensitivity analysis of recycling rate shows an approximately linear relation of inverse proportion between recycling rate and total environmental impact. Considering the limited financial resources and the current waste management practices in Macau, Scenario 4 would be the preferred choice.

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.

Source Analysis of Heavy Metals and Arsenic in Organic Fractions of Municipal Solid Waste in a Mega-City (Shanghai)

Heavy metals and arsenic contamination in municipal solid waste (MSW) and its treatment products has garnered increasing attention. This study investigated the heavy metals and arsenic flows in organic fractions of MSW (OFMSW) in Shanghai, China, through a one-year monitoring program. The OFMSW separated directly from the source (source-separated, pure organic waste), obtained from the treatment facilities were sampled and compared with pure foodstuffs. The heavy metals and arsenic contents in the source-separated OFMSW resembled those in foodstuffs, whereas the OFMSW from the treatment facilities was significantly contaminated with heavy metals and arsenic and failed to meet the government standards for land use. Using flow analysis, > 80% of heavy metals and arsenic were from extrinsic inorganic waste with high ash content that was combined with OFMSW during MSW collection, transfer, transportation, and storage stages. Based on source analysis of heavy metals and arsenic, suggestions for reducing heavy metals and arsenic contents in the current MSW management system in Shanghai are presented.