Sustainable Waste Management System Research Articles

Implementation of anaerobic digestion for valorizing the organic fraction of municipal solid waste in developing countries: Technical insights from a systematic review

Anaerobic digestion (AD) as a waste management strategy for the organic fraction of municipal waste (OFMSW) has received attention in developed countries for several decades, leading to the development of large-scale plants. In contrast, AD of OFMSW has only recently drawn attention in developing countries. This systematic review was carried out to investigate the implementation of AD to treat the OFMSW in developing countries, focusing on assessing pilot and full-scale AD plants reported in the last ten years. Studies that met the selection criteria were analyzed and data regarding operating parameters, feedstock characteristics, and biogas, digestate, and energy production were extracted. As outlined in this systematic review, AD plants located in developing countries are mostly one-stage mesophilic systems that treat OFMSW via mono-digestion, almost exclusively with the aim of producing electrical energy. Based on the analysis done throughout this systematic review, it was noted that there is a large difference in the maturity level of AD systems between developing and developed countries, mainly due to the economic capacity of developed countries to invest in sustainable waste management systems. However, the number of AD plants reported in scientific papers is significantly lower than the number of installed AD systems. Research articles regarding large-scale implementation of AD to treat OFMSW in developed countries were analyzed and compared with developing countries. This comparison identified practices used in plants in developed countries that could be utilized in the large-scale implementation and success of AD in developing countries. These practices include exploiting potential products with high market-values, forming partnerships with local industries to use industrial wastes as co-substrates, and exploring different biological and physical pretreatment technologies. Additionally, the analysis of capital and operational costs of AD plants showed that costs tend to be higher for developing countries due to their need to import of materials and equipment from developed countries. Technical, economical, and political challenges for the implementation of AD at a large-scale in developing countries are highlighted.

Developing an extended producer responsibility system for solid waste management in Jordan using multi-criteria decision-making approach.

To move from a traditional end of pipe approach into a more sustainable solid waste management system, the Jordanian Government has recently passed a set of new regulations The National Solid Waste Management Strategy has put a road map to encourage circular economy practices. One of the considered policy instruments is the adoption of the extended producer responsibility (EPR). The current study aimed to adopt a multi-criteria decision-making method to select the most convenient EPR structure within the Jordanian context. The study used analytical hierarchy process (AHP) and fuzzy AHP (FAHP) techniques to select the suitable type of producer responsibility organization (PRO) structure. A four-level hierarchy model was constructed with 4 criteria, 10 sub-criteria and 3 PRO alternatives. The analysis revealed that the legal and administrative criteria is the most important one (0.47) followed by environmental criteria (0.22), whereas the least important ones were socio-economic (0.17) and technical criteria (0.13). The most preferable PRO alternative was found to be PRO with profit. There were slight differences between all weight values under AHP and FAHP. Despite the availability of several laws, there is a need to develop the legal and administrative framework to enable the adoption of EPR in Jordan. Research should be the first step in the process of EPR system design. None of the previous studies conducted used the AHP and FAHP in assessing and selecting the EPR systems.

Advancing Plastic Waste Classification and Recycling Efficiency: Integrating Image Sensors and Deep Learning Algorithms

Plastics, with their versatility and cost-effectiveness, have become indispensable materials across various industries. However, the improper disposal and mismanagement of plastic waste have led to significant environmental issues, including pollution, habitat destruction, and threats to wildlife. To address these challenges, numerous methods for plastic waste sorting and recycling have been developed. While conventional techniques like near-infrared spectroscopy (NIRS) have been effective to some extent, they face difficulties in accurately classifying chemically similar samples, such as polyethylene terephthalate (PET) and PET-glycol (PET-G), which have similar chemical compositions but distinct physical characteristics. This paper introduces an approach that adapts image sensors and deep learning object detection algorithms; specifically, the You Only Look Once (YOLO) model, to enhance plastic waste classification based on the shape of the waste. Unlike conventional methods that rely solely on spectral analysis, our methodology aims to significantly improve the accuracy and efficiency of classifying plastics, especially when dealing with materials having similar chemical compositions but differing physical attributes. The system developed using image sensors and the YOLO model proves to be not only effective but also scalable and adaptable for various industrial and environmental applications. In our experiments, the results are strikingly effective. We achieved a classification accuracy rate exceeding 91.7% mean Average Precision (mAP) in distinguishing between PET and PET-G, surpassing conventional techniques by a considerable margin. The implications of this research extend far and wide. By enhancing the accuracy of plastic waste sorting and reducing misclassification rates, we can significantly boost recycling efficiency. The proposed approach contributes to a more sustainable and efficient plastic waste management system, alleviating the strain on landfills and mitigating the environmental impact of plastic waste, contributing to a cleaner and more sustainable environment.

Evaluation of potential power production and reduction in GHG emissions from bio-compressed natural gas derived from food waste in Africa

There is an increased food waste generation globally due to socio-cultural factors, inadequate food waste management, and economic factors. Developing countries have major issues with proper food waste management, contributing to several environmental problems. The ineffective food waste management in Africa has had detrimental consequences on the ecosystem and people's health. There is a need for an improved sustainable food waste management system on the continent. Biomethane from organic resources could be upgraded into bio-compressed natural gas (bio-CNG), which could be used as green fuel for the environment, climate, and human health. This study evaluates the environmental and electricity benefits of bio-CNG derived from food waste in African nations. The major findings show that the annual bio-CNG yield from food waste in Africa is 98.34 × 109 m3/y, and that could generate 4035.7 GWh/y of electricity. The annual electricity generation could contribute 3.4 % (on average) to Africa's estimated electricity needs (798,958.7 GWh). The findings also show that using energy generated from bio-CNG could substitute for 94.47 million L of diesel fuel annually, resulting in a 256.71 kt CO2eq/y reduction in global warming. This research has the potential to inform policy decisions on the ecological viability of bio-CNG to power projects in Africa and other developing nations.

A multi-objective closed-loop supply chain under uncertainty: An efficient Lagrangian relaxation reformulation using a neighborhood-based algorithm

Population growth and unprecedented industrialization have contributed to a significant surge in global waste generation, underscoring the need for efficient waste management practices such as recycling, disassembling, restoration, and disposal. Closed-loop supply chain (CLSC) networks offer a solution for effective waste management by enabling the recycling, reassembly, and reuse of waste products. However, designing an optimal CLSC network presents challenges due to uncertainties associated with various parameters, including customer demand, sustainable development goals, and the complexity of network design optimization. This paper addresses these challenges by proposing a comprehensive CLSC network that optimizes environmental, economic, and social footprints through a multi-objective optimization approach. To account for parameter uncertainties, we employ scenario generation using a scenario-based stochastic programming procedure. To solve the proposed model, we transform the multi-objective formulation into a single-objective model using a weighted sum method considering a set of problem-specific heuristics. Furthermore, we leverage Lagrangian relaxation theory to formulate various problem reformulations, aimed at attaining an optimal lower bound for the CLSC problem. We complement this with a neighborhood-based algorithm that helps identify a feasible upper bound. By utilizing a sub-gradient framework, we iteratively reoptimize both the selected reformulation and the neighborhood-based algorithm, culminating in the achievement of an optimal solution. To exemplify the practical applicability of our research, we present a case study focusing on the light engineering industry in Bangladesh. Through rigorous analyses, we showcase that our proposed algorithm can deliver an optimal solution with an optimality gap of 0.06. By offering insights into the successful implementation of our CLSC network in a real-world context, we aim to provide valuable guidance for practitioners seeking to establish efficient and sustainable waste management systems.

Sustainable Waste Management in the Production of Medicinal and Aromatic Plants—A Systematic Review

Without a Sustainable Waste Management (SWM) system, the growing demand for Medicinal and Aromatic Plants (MAPs) can also lead to a considerable increase in the waste generated by the industry. Since MAP residues have a notable potential to be valorised, the implementation of Circular Economy (CE) solutions can play a central role in converting waste into economic opportunities, while fostering a sustainable planet. CE helps to mitigate environmental and social risks caused by the accumulation of biomass by turning waste into valuable products. A systematic review was conducted, aiming to identify potential applications for the valorisation of MAP residues under a sustainable approach. A total number of 47 studies were analysed, providing a novel compilation of possibilities for decision makers in the MAP industry to develop new products for crop management or new businesses in food, cosmetic, pharmaceutical, chemical, paper, or building industries. Researchers in this field have focused more on the industrial value of MAP residues than on the empirical assessment of environmental and economic benefits. Further investigation should be undertaken to present empirical applications and to develop a decision support system to assess the sustainable performance of valorisation options.

An assessment of the current situation and recommendation of management scenarios for municipal solid waste management in Ho Chi Minh city

Ho Chi Minh city (HCMC) is currently facing a critical problem of the uncontrollable municipal solid waste (MSW). The most common waste disposal practice in the city is landfilling, but this is not a sustainable solution. From 2010 to 2022, the amount of waste generated has increased annually, from 6,000 tons/day to 9,200 tons/day, with an average growth rate of 6-8% per year. This study calculated the average emission factor of various districts in the city such as districts 1, 3, etc. at 0.83 kg/capita/day and district Binh Chanh, Cu Chi, etc. at 0.73 kg/capita/day and forecasted that the amount of waste will reach approximately 16,100 tons/day by 2050. Currently, 80-90% of collected MSW is landfilled, while only 10% is recycled. Composting and energy recovery practices are rarely used. This paper reviewed the current solid waste practice in HCMC and proposed four management scenarios to develop a sustainable solid waste management system. The first scenario is landfilling, which involves non-segregated waste disposal at the source. The second scenario is recycling, which involves segregating waste at the source for recycling, reuse, and waste reduction. The third scenario is composting, which requires using a mechanical-biological treatment plant for sorting, composting, and producing fuel from waste. The fourth scenario is waste-to-energy, which uses a waste incineration plant to generate energy from waste.

Involvement in the Economic Circulation of Production Waste: Russian and European Experience

Introduction. The involvement in the economic circulation of production waste is one of the priority objects within which sustainable development is implemented. The purpose of the article is to explore the issues of waste generation and directions for their use in statistical, legal, strategic and economic contexts, to compare approaches to the involvement of waste in economic circulation in Russia and the European Union countries. Materials and Methods. The study used data from the Federal State Statistics Service of the Russian Federation and the Statistical Service of the European Union. Using the methods of descriptive statistics, the indicators of the generation and usage of waste in Russia and the European Union countries have been studied; the methods of comparative analysis made it possible to consider the directions of involving production waste in economic circulation by sectors of the economy and approaches to involving waste in economic circulation in Russia and the European Union countries. Using the method of generalization and synthesis of profits in transactions, the authors made the main conclusions. Results. It is concluded that, despite the discovery of unresolved problems with production waste, the European approach to identify waste achieves the certain results, in particular, sustainable waste management systems have been established and instruments aimed at preventing and reducing waste, increasing the content of recycling are being applied. In Russia, for the most part, this refers to promising areas, based on international best practices, in the specific experience of the European Union countries, it is assumed that the industry processing, utilizing and neutralizing waste will be observed and prescribed. Discussion and Conclusion. It has been revealed that the problem of waste exists both in Russia and in the European Union countries, but each time it is approached differently. In general, the countries have created a system for dealing with regulation of waste production, have designed targeted strategies aimed at creating a circular economy. The results of the analysis carried out are of practical importance, they can be taken into account by other countries in the process of developing and making a decision on the problem of production waste.

Waste Generation Modeling Using System Dynamics with Seasonal and Educational Considerations

Effective waste management is critical to environmental sustainability and public health. Various dynamics, such as seasonal changes and waste education programs, influence solid waste generation, increasing the complexity of prediction. This is important, as the proper prediction of waste quantity is necessary to develop a sustainable waste management system. In this study, municipal solid waste (MSW) management is examined in Regina, the capital city of Saskatchewan, Canada. A system dynamics (SD) model is developed to evaluate garbage and recyclable waste generation behaviours in Regina across four seasons. Three years of Regina landfill waste generation records (2016–2018) are considered to analyze and predict seasonal waste-generation trends. The effect of various factors, such as gross domestic product (GDP), population, and education attainment on the amount of waste generation is considered in the SD model. The SD model is designed as a stock-flow diagram to illustrate the relationships between variables and predict the next three years of waste trends. This finding highlights the importance of waste education and awareness program and seasonal effects on the accuracy of SD waste modeling.

Determining environmental ethics, personal norm, knowledge, and waste separation behaviour among households

The behaviour of separation of waste at the source has been identified as one of the key elements towards sustainable waste management which aims to prevent pollution and ultimately preserve the environment. However, the rate of waste separation in Malaysia is still low. Environmental ethics, personal norm and knowledge on waste separation have been identified as among the internal factors influencing household waste separation behaviour. The study employed quantitative research design with online questionnaire as a method of data acquisition while the study population is households in landed properties in the district of Kluang, Johor. Results show that the level of waste separation behaviours, personal norm towards waste separation and knowledge on waste separation are moderate. The study also found that households are holding ecocentric and biocentric environmental ethics orientation, indicating a good sign for pro-environmental support and behaviours through the activation of personal norm. The findings of the study can be used by stakeholders in formulating policies, initiatives, programmes and strategies towards sustainable waste separation among households as part of the whole sustainable waste management system in the country.

Charting success for the Plastics Treaty

Charting success for the Plastics Treaty

Revolutionizing municipal solid waste management (MSWM) with machine learning as a clean resource: Opportunities, challenges and solutions

Effective municipal solid waste management is essential for public health, environmental protection, economic benefits, and clean energy generation for future commercial applications. However, challenges like real-time monitoring, automated sorting systems, optimized collection routes, predictive maintenance, and public education and engagement hinder efficiency. Machine learning can address these challenges through real-time monitoring, automated sorting, route optimization, predictive maintenance, and targeted public education. Supervised, unsupervised, and reinforcement learning can be applied to various waste management processes, enhancing energy extraction and clean fuel production for commercial sectors like the steel industry. Machine learning can effectively predict waste generation, design collection routes, classify waste materials, forecast real-time landfill filling rates, detect operational issues, prevent illicit dumping, and establish predictive maintenance systems. However, it must be integrated with other strategies, policies, and regulations for a sustainable waste management system. Additionally, cost-benefit analyses, scalability, and implementation feasibility should be considered before investing. In conclusion, machine learning can improve municipal solid waste management efficiency and effectiveness, but further research is needed. The present study offers vital knowledge for key stakeholders, including successful case studies and evaluations of societal technology and customer readiness levels.

Strategic waste management practices for environmental sustainability – a case of Indian university

PurposeIndividuals generate plenty of waste that is affecting the life while consumption of air and water at the base. The increasing industrialization, population and waste generation without proper measures of waste management are leading to major challenges to environmental sustainability. Considering these challenges, the present study focuses on the types and sources of waste generation and waste reduction by encouraging the reduction, recycling and reuse of waste products. The study aims to provide a well-functioning sustainable waste management system, that incorporates feedback loops, focuses on processes, embodies adaptability and diverts waste from disposal.Design/methodology/approachThe university under study is situated at the central location of Pune City in India. The university has diverse units like academic and admin buildings, canteens and mess, hostels, a clinic, workshops and gardens. To fulfil the objective of this study a qualitative case study approach of research was adopted. A total of thirty-three representatives and waste management personnel from various units of the university were interviewed. The interviews were semi-structured and the duration of it was around 25–55 min. The interview transcripts were coded, and qualitative analysis was conducted.FindingsThis study proposes a strategic sustainable waste management model for environmental sustainability that brings circularity by closing the loops and focusing on sustainable development goals.Practical implicationsThe findings of this research can guide universities to manage the waste generated through various sources and attain sustainable development goals and environmental sustainability at large by closing the loops. The study provides insights into waste management and environmental sustainability. The universities can make their resources more circular by following the strategies of reducing, reusing and recycling (3R). This study recommends customization according to the needs of specific universities and institutions. Researchers can take this study further by testing and customizing it as per requirement. Also, an effort can be extended to implement the model in other related areas.Originality/valueThis research is a unique attempt to advance knowledge of waste management practices for sustainable development by exploring different techniques opted by for individual entities from the university campus to understand the environmental impact.

A framework for achieving a circular economy using the blockchain technology in a sustainable waste management system

In a circular economy, the use of blockchain applied to different models like the waste management process leads to sustainable solutions alternative to the non-efficient linear economy. This study proposes a new methodology capable of optimizing the waste management process through an enabling technology: the blockchain. An innovative method that can increase monitoring while reducing the general costs of waste management is proposed. A blockchain system is developed for the control of urban waste. In addition, a reward mechanism is established for the citizens in terms of the levels of sorted waste produced and the working procedures of the agency that manages waste collection are optimized. A mathematical model that formalizes the problem for an optimal solution to minimize the costs of all the stakeholders involved in the Waste Management process is also developed. The characteristics that the proposed system allows are very important for the entire process of solid waste management. In fact, the adoption of the blockchain enables full traceability of the waste, ascertainability of each action, and the possibility that every customer can directly verify the information that is stored in the blockchain, such as the quantity of disposed waste, the amount of his reward and several additional data. Last but not least, the integrity of all stored records is fundamental in order to enforce the trust between the citizen and the Municipality that is in charge of dealing with solid waste management.

The Plastic Waste And its Management in Tanzania: A Case of Arusha Municipality

This study sought to determine the value of plastic waste management in Tanzania, Arusha Municipality. A survey study was deployed, with a sampled population of 130 respondents from Arusha Municipality obtained through purposive and random sampling methods. Environmental Responsible Behaviour Theory and Waste management Theory guided the study. Data were analysed using descriptive analysis for quantitative data and thematic analysis for qualitative data. The following results were obtained; lack of resources in the municipal has led to inefficient waste management, the level of awareness on sustainable waste management systems is not substantial due to lack of sources of information and knowledge as they are a key factor in influencing the perception on the value of plastic waste and also putting into practise sustainable waste management systems that are used. In order to effectively practice sustainable waste management policies and increase in resources need to be established along with an increase in formal and informal education on waste management to the society.

Plastic management to reduce environmental pollution

There is an infinity of plastic products which have facilitated human life, but have also caused great environmental pollution that affects flora, fauna and of course the human being. Such is the use of polyethylene terephthalate (PET), which is a widely used plastic throughout the world, in Mexico and in each of the states and municipalities that comprise it. The vast majority of organizations, scientists, and others have understood this situation and have promulgated laws, designed strategies, environmental programs, etc. in order to contain or reduce their use or even recycle and reuse these materials, since once they are discarded they become polluting materials. Objective: Given this situation, this project is proposed whose objective is to design a program to reduce the contamination generated by polyethylene terephthalate (PET) mainly among other plastics in the municipality of Silacayoápam, Oaxaca, Mexico and in turn reactivate the local economy in small businesses stores through exchanges for basic basket products. Method: Using the documentary analysis technique, primary information was collected by conducting a direct survey of the inhabitants of the municipality, after which it was systematized in data record sheets, and the main challenges posed by the use of the polymer in the municipality were identified. Results: with the data collected, strategies for the use of plastic were analyzed and proposed, designing a management program for PET and other plastics for the local area that helps reduce environmental impact, and also promote environmental culture in the municipality and on the other. side and perhaps more important is to reactivate the economy of local businesses. Discussion and conclusions: the generation of this type of strategies allows, on the one hand, to have a culture of collection and recycling and, on the other hand, to support small businesses affected by the pandemic and the inflation of basic basket products, this represents an enormous challenge in the region and at the national level to define a more efficient, inclusive and sustainable waste management system, to reduce health and environmental problems.

Potential environmental impacts of a plastic waste export ban in Germany

Up to 800,000 t/a of plastic waste generated in Germany is exported, of which more than a quarter is packaging. However, a sustainable waste management system aims at treating waste under consideration of environmental benefits generation and the reduction of negative environmental impacts. Thus, this brief research deals with the question to what extent negative environmental impacts could be avoided by an export ban. Further, this brief research serves as a preliminary basis for further discussions and studies in the field of the plastic export ban. Two scenarios were developed based on expert interviews to estimate alternative management for the otherwise exported plastic waste generated in Germany. A consequential life cycle assessment (LCA) was carried out to look into the possible Global Warming Potential changes of such scenarios compared to the current situation scenario. The LCA showed that an export ban in Germany offers the possibility of avoiding up to 80 CO2-equivalent per ton of exported packaging plastic. However, this would be only possible if most of the plastic packaging that is no longer exported is recycled and not burned for energy production in the case of Germany.

Mass Balance Analysis of Integrated Municipal Solid Waste Management: The Jakarta Recycle Center Program Case Study

With the amount of waste increasing and landfill space becoming critical, the government has undertaken numerous measures to reduce waste, including creation of Integrated Solid Waste Management system through Jakarta Recycle Centre (JRC) Program. An integrated and sustainable waste management system will depend on both the physical and the governance components, with the physical aspect focusing on technical problems. To evaluate the physical aspect of JRC, the flow of the waste needs to be monitored and evaluated to see the success of waste separation and recycling system. This study employs mass balance analysis using data of waste in JRC facilities from January to December 2022. According to the study's findings, JRC system has a significant recycling rate which is around 46,43%. To improve the recycling rate, communication to residents about waste sorting process need to be enhanced. In order to reduce residue from sorting outcomes, it is also crucial to increase the ability and expertise of personnel in waste sorting.

Multi-objective optimization and 4E analysis of an integrated system based on waste-to-energy, solar PV, power-to-gas, and HDH-RO desalination

Waste-to-energy technology is among the most important parts of a sustainable waste management system nowadays. By adding a renewable source of electricity (solar photovoltaics) and power to gas (proton exchange membrane electrolyzer and the Sabatier reactor) to convert CO2, the environmental problems of waste to energy plants (here incineration and landfill) can be tackled. To solve freshwater scarcity issues, two desalination units (reverse osmosis and humidification and dehumidification) are added to the system. The main novelty of this study is to produce beneficial outputs from municipal solid waste and solar energy. The system is analysed comprehensively from energy, exergy, economic, and environmental viewpoints. The energy and exergy efficiency of the system is 17.48 % and 15.15 %, respectively, and the net power production is 8.42 MW. From economic and environmental points of view, the total annual cost is €12.12 million and CO2 conversion is 99.96 %. The parametric study is conducted on the effect of important parameters. Furthermore, multi-objective optimization is performed by using a genetic algorithm with the objectives of maximizing exergy efficiency and minimizing total annual cost. The optimum solution provides the exergy efficiency of 20.70 % with the total annual cost of €12.75 million.

Modeling and usage of a sustainametric technique for measuring the life-cycle performance of a waste management system: A case study of South Africa

The use of eco-friendly materials, waste prevention protocols, the support and participation of building construction stakeholders, polluter pays concepts, producer responsibility, life-cycle system thinking, and the application of cost-efficiency and cost minimization strategies are some of the guiding philosophies that are of extreme value when designing a waste management system via circular economy initiatives. However, it is crucial to measure the waste management strategy used in each building project. In order to measure the life-cycle performance of waste management systems and to assess how sustainable they are, this study offers a statistical methodology using a sustainametric technique to indicate how sustainable waste management system performance in emerging construction industries, particularly in South Africa. This study employs a sustainametric approach to evaluate the life-cycle performance of the waste management system of South Africa, with evidence of its sustainability performance measurement that can help advance the its waste minimization policy and implementation. The result indicates the viability of the measuring model and the findings of each metric utilized. The conclusion confirms that South Africa has not fully adopted and/or implemented a more sustainable waste management system for efficient waste minimization during its construction activities. Moreover, it is the reality that most emerging economies urgently need to expand and improve the waste reduction method employed in its construction building projects.