Waste management developments in the last five decades: Asian perspective

Solid waste management was explored in Asia's last five decades, and the issues and challenges were identified. Waste generation has increased in all nations in the previous 50 years, although more recently, a declining trend has been observed in Japan and Korea. The composition has been predominantly organic, with 45-50% being kitchen waste. Material extraction and productivity to sustain the most populous part of the globe are explained. Waste management technologies have evolved, with more nations slowly transitioning from landfills to using waste-to-energy options. However, landfilling and open dumps are still the major disposal choice in most developing countries in Asia. Thus, the issues of concern include dumpsites management, the informal sector, waste collection, open burning and food waste. Changes (increasing trends) in the recycling technologies and quantum are evident, as seen in several country reports from India, Indonesia, Japan, Malaysia, Singapore, South Korea, Thailand and Vietnam. There are several issues and challenges for recycling, which are explored in the text. Lastly, the drivers that propel the whole scenario of waste management in Asia and the evolution of these drivers over time are discussed. Several recommendations are included to achieve sustainable waste management in Asia.

An Evaluation of the Impact of Illegal Dumping of Solid Waste on Public Health in Nigeria: A Case Study of Lagos State

The illegal dumping of solid waste is a prevalent issue in Nigeria, affecting all states. Lagos State, in particular, faces waste disposal problems that stem from urbanization, negative public perception towards waste management, insufficient waste disposal education, poor waste disposal practices, and the disposal of waste at illegal and unauthorized sites. This situation is further exacerbated by inadequate municipal solid waste (MSW) collection rates, making it challenging to combat illegal dumping effectively. To align with Sustainable Development Goal (SDG) 11 of Sustainable Cities, which seeks to minimize negative environmental effects associated with managing MSW by 2030, this study aims to assess the environmental and health impact of illegal dumping of solid waste in Lagos State. The objectives of this study include assessing people's attitudes towards illegal dumping, evaluating the extent of environmental degradation resulting from illegal solid waste dumping in Lagos, and assessing the health risks associated with exposure to illegally dumped solid waste in Lagos State, as well as determining if illegal dumping contributes to the diseases prevalent in Lagos State. This study will use a quantitative approach to collect data from study participants on demographics, educational background, waste management, and environmental and health issues using computer-assisted self-administered questionnaires (Google Forms). This study will also use observations and photographs of illegally dumped waste in communities and major illegal dumpsites in the study area to provide valuable information to complement the questionnaire responses. By combining both approaches, the study will be able to capture both numerical data and people's behaviors and attitudes associated with illegal dumping. This study will use a mixed sampling method consisting of cluster sampling and convenience sampling, focusing on communities impacted by illegal dumping in Lagos State. The sample size for this study will be 100. The questionnaire for this study will be administered via a Google Forms link that will be shared through various online platforms, enabling participants to access and complete the questionnaire from any location with internet access. To ensure representative participation, as part of the informed consent form on the initial page of the online questionnaire, a screening question that requires participants to indicate if they live or work in the study areas or have been exposed to the impact of illegal dumping will be included. Only those who meet these criteria will be able to proceed with the study. The primary data obtained will be carefully analyzed using the Statistical Package for the Social Sciences (SPSS) version 28. The study's results will highlight the importance of the linkage between illegal dumping, environmental degradation, and diseases prevalent in Lagos State, which could inform policymakers and relevant departments in developing effective strategies to improve public health.

Analysis of the influence of the COVID-19 outbreak on household solid waste management: An empirical study using PLS-SEM

The global increase in solid waste pollution due to economic growth and population growth has led to severe ecological deterioration. This situation is exacerbated by the ongoing coronavirus disease (COVID-19) pandemic, which has significantly impacted consumer behavior and consumption habits. Proper management of solid waste has thus become critical in mitigating environmental degradation. In this study, we aim to examine the relationship between the outbreak of COVID-19, environmental attitudes (EATT), social norms (SN), environmental knowledge (EK), technological innovation (TI), and solid waste management (SWM) in Ecuadorian households during the pandemic. We collected data from 426 households in Ecuador using an online questionnaire and analyzed it using the Partial Least Squares Structural Equation Model method to test the hypotheses. Likewise, we validated the measurement and structural model. The results are novel about SWM, considering a developing country severely affected during the pandemic. Our findings suggest that COVID-19 has a negative impact on SWM, while EATT, SN, and TI have a positive influence on SWM. However, we found that EK does not significantly affect SWM.

Can tourism support resource circularity in small islands? On-field analysis and intervention proposals in Madagascar

Open dumping and burning of solid waste are common practices in low-income countries. On small and touristic islands, the problem is exacerbated due to the additional volume of waste amount generated by tourists. This article presents how, using Nosy Be island in Madagascar as a case study, waste recovery and recycling can be fostered by tourism to tackle the waste challenge. About 95% of the waste of Nosy Be is openly dumped, discarded to sea or openly burned. Field analysis, interviews with local stakeholders and waste flow analysis served as methodological tools to assess the current solid waste management (SWM) system of Nosy Be. Stakeholder mapping and involvement as well as first exchange among local and international actors provided the basis to identify key practice and opportunities. Research findings highlight the importance of active participation and involvement of local partners supported by international experts, to suggest how touristic centres can serve as core of circular approaches. The article presents potential circular models to be implemented in Nosy Be, taking tourism as the entry point including the aspects of financial support, separated waste flows and the interest in 'green tourism marketing'. This case study underlines how international cooperation, touristic activities and common efforts can potentially help low-income communities improve their SWM practices.

A mini review on the main challenges of implementing mechanical biological treatment plants for municipal solid waste in the Latin America region: Learning from the experiences of developed countries

Most of the municipal solid waste (MSW) generated in the Latin America (LATAM) region is currently disposed of in landfills and dumpsites, which results in many negative environmental impacts. Mechanical biological treatment (MBT) is a strategy that combines the mechanical separation of recoverable materials with the biological stabilization of organic matter. MBT plants have proven to be a good alternative for the management of MSW and have been successfully implemented in developed countries for more than 30 years. However, the efficient introduction of these facilities in developing countries, such as those in the LATAM region, requires further feasibility studies. Therefore, this mini review seeks to offer significant insights into the main challenges that must be overcome to facilitate the implementation and operation of MBT plants, considering the unique technological, sociocultural, economic and political context of the LATAM region, through a comparison of the reported experiences of MBT plants in more developed countries with those in the LATAM region. The analysis herein indicates that key actions for the successful operation of MBT plants in the LATAM region include both the implementation of source separation as well as selective collection practices. Moreover, this work shows that other factors, like the establishment of valorization markets with safe working conditions for informal collectors, the development of intermunicipal cooperation schemes and the enforcement of strong regulatory frameworks for waste disposal specifications, are important contextual factors that have allowed the efficient operation of MBT plants in developed countries. Although the implementation of many of these practices will be challenging, such measures are necessary to increase the sustainability of MSW treatment practices in the LATAM region.

Investigation of reactions occurring in waste combustion ash using thermal analysis coupled with gas analysis and characterization

Waste-to-energy (WtE) ash was investigated for thermal reactions that generate gas components such as hydrogen and carbon dioxide. An evolved gas detection method coupled with thermal gravimetric analysis and differential scanning calorimetry provided insight into the possible reactions occurring in WtE ash at temperatures ranging from 90°C to 600°C in an inert environment. The combined analysis shows that H₂ is produced from WtE ash at temperatures ~298°C and is detected until ~480°C. CO₂ appears in the evolved gas starting at 290°C and continues to increase as the temperature is increased. The results reveal that the processes releasing H₂ and the CO₂ are independent of each other, and the CO₂ generation depends on the constant input of energy. These results enable the identification of the possible processes occurring in WtE ash decomposition of Friedel's salt at 280°C and dehydration of Ca(OH)₂ at 410°C, both of which release H₂O that reacts with the aluminium present to release H₂. At temperatures higher than 480°C, an alumina layer is formed preventing further production of H₂. X-ray diffraction analysis done on the WtE ash verifies the presence of chemical phases that support the proposed reactions. The outcome of this study enables identifying the possible reactions in WtE ash that can be causing the energy changes seen during disposal, storage and transportation of ash. These results can give direction for detailed understanding and development of the kinetics and the mechanisms of the reactions occurring in WtE ash which is important for optimization of reuse and disposal of ash.

Circular economy approach for sustainable solid waste management: A developing economy perspective

The notion of circular economy (CE) strengthens the approach to sustainable development (SD). It is perceived that the adoption of CE can unlock half a trillion dollars of economic value in India by the year 2030. However, embracing the CE concept can be considered a panacea to the existing issues associated with solid waste management (SWM). The proposed study explores current waste management practices and assesses the inadequacy to infer the CE as a solution for successful waste management practices. The work provides an overview of SWM in India and emphasizes the inclusion of CE in the Indian SWM sector. The comprehensive review depicts existing, and emerging waste management approaches to form a CE by processing the waste efficiently and fuelling an SD movement. The cradle-to-cradle approach in CE, national solid waste compliances/legislation, key initiatives taken by the Governments, and the influence of industry and legal framework on CE were also discussed. The work will facilitate policy and decision-makers to include CE in the Indian SWM sector.

Comparative Analysis of the Implementation of Support Vector Machines and Long Short-Term Memory Artificial Neural Networks in Municipal Solid Waste Management Models in Megacities

The development of methodologies to support decision-making in municipal solid waste (MSW) management processes is of great interest for municipal administrations. Artificial intelligence (AI) techniques provide multiple tools for designing algorithms to objectively analyze data while creating highly precise models. Support vector machines and neuronal networks are formed by AI applications offering optimization solutions at different managing stages. In this paper, an implementation and comparison of the results obtained by two AI methods on a solid waste management problem is shown. Support vector machine (SVM) and long short-term memory (LSTM) network techniques have been used. The implementation of LSTM took into account different configurations, temporal filtering and annual calculations of solid waste collection periods. Results show that the SVM method properly fits selected data and yields consistent regression curves, even with very limited training data, leading to more accurate results than those obtained by the LSTM method.

Microbial Enzyme Biotechnology to Reach Plastic Waste Circularity: Current Status, Problems and Perspectives

The accumulation of synthetic plastic waste in the environment has become a global concern. Microbial enzymes (purified or as whole-cell biocatalysts) represent emerging biotechnological tools for waste circularity; they can depolymerize materials into reusable building blocks, but their contribution must be considered within the context of present waste management practices. This review reports on the prospective of biotechnological tools for plastic bio-recycling within the framework of plastic waste management in Europe. Available biotechnology tools can support polyethylene terephthalate (PET) recycling. However, PET represents only ≈7% of unrecycled plastic waste. Polyurethanes, the principal unrecycled waste fraction, together with other thermosets and more recalcitrant thermoplastics (e.g., polyolefins) are the next plausible target for enzyme-based depolymerization, even if this process is currently effective only on ideal polyester-based polymers. To extend the contribution of biotechnology to plastic circularity, optimization of collection and sorting systems should be considered to feed chemoenzymatic technologies for the treatment of more recalcitrant and mixed polymers. In addition, new bio-based technologies with a lower environmental impact in comparison with the present approaches should be developed to depolymerize (available or new) plastic materials, that should be designed for the required durability and for being susceptible to the action of enzymes.

Quantifying odour impacts from aged organic waste to be considered as a priority constraint in route optimization for waste collection trucks

Route optimization has been used for years to plan the routes for municipal solid waste (MSW) collection trucks to achieve cost reductions. Historically, optimized routes had overlooked a number of aspects and parameters in their design. This study aims to consider MSW odour detection as a performance indicator and a priority constraint in the optimization process by quantifying the impact of objectionable odours from uncollected aged MSW that contains a high percentage of food waste (typically called wet garbage). Odours from 48 aged food waste samples were rated on a scale from 0 to 3 to mark the beginning of the critical time of objectionable odour detection. The critical time was found to take place approximately at the hour 13.6, which was then used, along with the estimated food waste weight in the bin, to define the beginning of a time window that puts the bin on a high priority status for collection over the other, less odoriferous bins. Three optimization scenarios for collection of 100 MSW bins in the city of Madaba, Jordan, were conducted under different constraints: least travelled distance, maximum collected volume and least odour impact. Without the application of the odour consideration, a total travelled distance of 143 km was the shortest travelled distance achieved, with 53 bins emitting odours and leaving 81 m³ of uncollected waste. However, when odour impact was the main routing constraint, a total travelled distance of 161 km was needed and 13 m³ of waste was left uncollected.

Environmental Sustainability Impacts of Solid Waste Management Practices in the Global South

Solid waste management (SWM) is one of the key responsibilities of city administrators and one of the effective proxies for good governance. Effective SWM mitigates adverse health and environmental impacts, conserves resources, and improves the livability of cities. However, unsustainable SWM practices, exacerbated by rapid urbanization and financial and institutional limitations, negatively impact public health and environmental sustainability. This review article assesses the human and environmental health impacts of SWM practices in the Global South cities that are the future of global urbanization. The study employs desktop research methodology based on in-depth analysis of secondary data and literature, including official documents and published articles. It finds that the commonplace SWM practices include mixing household and commercial garbage with hazardous waste during storage and handling. While waste storage is largely in old or poorly managed facilities such as storage containers, the transportation system is often deficient and informal. The disposal methods are predominantly via uncontrolled dumping, open-air incinerators, and landfills. The negative impacts of such practices include air and water pollution, land degradation, emissions of methane and hazardous leachate, and climate change. These impacts impose significant environmental and public health costs on residents with marginalized social groups mostly affected. The paper concludes with recommendations for mitigating the public and environmental health risks associated with the existing SWM practices in the Global South.

Drivers of Solid Waste Segregation and Recycling in Kampala Slums, Uganda: A Qualitative Exploration Using the Behavior Centered Design Model

Solid-waste management is a challenge in many cities, especially in low-income countries, including Uganda. Simple and inexpensive strategies such as solid-waste segregation and recycling have the potential to reduce risks associated with indiscriminate waste management. Unfortunately, these strategies have not been studied and adopted in slums in low-income countries. This cross-sectional qualitative study, therefore, used the behavioral-centered design model to understand the drivers of recycling in Kampala slums. Data were coded using ATLAS ti version 7.0, and content analysis was used for interpreting the findings. Our findings revealed that the study practices were not yet habitual and were driven by the presence of physical space for segregation containers, and functional social networks in the communities. Additionally, financial rewards and awareness related to the recycling benefits, and available community support were found to be critical drivers. The availability of infrastructure and objects for segregation and recycling and the influence of politics and policies were identified. There is, therefore, need for both the public and private sector to engage in developing and implementing the relevant laws and policies on solid waste recycling, increase community awareness of the critical behavior, and create sustainable markets for waste segregated and recycled products.

Challenges confronting waste pickers in Indonesia: An on-field analysis

This article presents the informal recycling sector's (IRS) social, economic driving factors in five cities in Indonesia and their contribution to waste management in the cities. An on-field analysis was conducted by random and incidental sampling method of questionnaire administration followed by observation. Among the respondents (n = 178), 79% of individuals were waste pickers, 15% were small-scale waste collectors, and 6% were medium-scale waste collectors. The majority of the waste pickers sampled are male (79%). The amount of waste collected by individual waste pickers is 43.87 kg person^-1 day^-1, a corresponding recycling rate of approximately 12%, and an average monthly income of US$91.7. Gender differences are apparent as the male waste pickers generated higher incomes than those earned by their female counterparts (US$128.3 for men and US$69.7 for women) even as their average work hours are similar to that of the men (7.8 and 7.6 hours day^-1, respectively). Economic motives are the respondents' primary driving factors as moving to large cities accompanied by their family members. The study concluded that the IRS plays substantial contribution to waste management; further integrating them into the waste management system via IRS association, additional investment, formulation of law and policies and efforts by municipalities can give various benefits for involved stakeholders, the community and the environment. The results can serve as a significant reference for improving the solid waste recycling system and informal sector management in Indonesian cities and other developing countries.

The Status of Household Solid Waste Management and its Associated Factors in Fiche Town, North Shewa Zone, Ethiopia

BACKGROUND

Poor solid waste management is a major public health and environmental concern in developing countries like Ethiopia. This study aimed to assess the status of household solid waste management and associated factors in Fiche town.

METHODS

A community-based cross-sectional study was conducted among 236 residents of Fiche town from January to March 2022. Both questionnaire and field observation was used to collect data from households in the town. Data were first checked manually for completeness, then coded and entered into SPSS version 20, then descriptive statistics such as frequency and percentage were done. Multivariate logistic regression analysis was done to assess the potential predictors of the outcome variable (P < .05).

RESULT

In the present study, 185 (78.4%), of residents uses improper solid waste management practices. Multivariable logistic regression analysis revealed that knowledge of reduce, reuse and recycle (3R) (adjusted odds ratio [AOR] = 6.61; 95% confidence interval [CI] 2.94, 14.87), access to door to door waste collection (AOR = 3.91; 95% CI 2.03, 7.51), treating waste as a resource (AOR = 3.06; 95% CI 1.47, 6.36) and knowledge about the rule and regulations of solid waste management (AOR = 6.49; 95% CI 3.09, 13.61) were found to be significantly associated with waste management practices.

CONCLUSION

Therefore, there is a need to raise awareness about solid waste management at the community level using different pieces of training. In addition, the city municipality needs to strengthen door to door waste collection services.

Predicting the Intention to Sort Waste at Home in Rural Communities in Lebanon: An Application of the Theory of Planned Behaviour

Low- and middle-income countries (LMICs) such as Lebanon have limited technical, economic, and social infrastructures to manage municipal solid waste properly. Understanding what motivates citizens to sort waste at home is paramount to designing effective, efficient, and equitable waste management interventions. Within the solid waste management project “RES-Q” in Southern Lebanon, we investigated the socio-cognitive predictors of waste sorting in a sample of 767 households from the targeted area using the Theory of Planned Behaviour (TPB). Perceived behavioural control (β = 0.96, p < 0.001), perceived norms (β = −0.30, p < 0.001), and current behaviour (β = 0.06, p < 0.001) were the strongest predictors of intention; attitude toward separating waste was not a significant predictor (β = 0.04, p = 0.3881). Consequently, future behavioural interventions should build capability and opportunity to perform the behaviour before normalising it. For example, citizens should receive bins and bags to separate waste and be shown how to perform the behaviour and how easy and convenient it is to increase their behavioural control. In parallel, waste collection and treatment infrastructures must be in place so that citizens can see that sorting waste is a social norm. These actions will ensure the success of future behavioural interventions within the RES-Q project and beyond.

Environmental assessment of construction and demolition waste recycling in Bolivia: Focus on transportation distances and selective collection rates

Construction and demolition waste (CDW) management in developing countries is a global concern. The analysis of scenarios and the implementation of life cycle assessment (LCA) support decision-makers in introducing integrated CDW management systems. This paper introduces the application of an LCA in La Paz (Bolivia), where CDW is mainly dumped in open areas. The aim of the research is to evaluate the benefits of inert CDW recycling in function of the selective collection rate, defined as the amount of waste (%_wt.) sorted at the source in relation to the total waste amount produced, and the distances from the CDW generation to the material recycling facility. The outcomes of the research suggest that increasing the selective collection rates (5% to 99%) spread the importance of transportation distances planning since it affects the magnitude of the environmental impacts (1.05 tCO₂-eq to 20.7 tCO₂-eq per km traveled). Transportation limits have been found to be lower than about 40 km in order to make recycling beneficial for all environmental impacts and for all selective collection rate, with the eutrophication potential as the limiting indicator. The theoretical analysis suggests implementing LCA with primary data and involving statistics related to the transportation of virgin materials avoided thanks to recycling. The outcomes of the research support the implementation of CDW recycling in developing countries since it has been found that material recovery is always beneficial.

Sensor-Based Solid Waste Handling Systems: A Survey

As a consequence of swiftly growing populations in the urban areas, larger quantities of solid waste also form rapidly. Since urban local bodies are found to be unable to manage this perilous situation effectively, there is a high probability of risks relative to the environment and public health. A sudden change is indispensable in the existing systems that are developed for the collection, transportation, and disposal of solid waste, which are entangled in turmoil. However, Smart sensors and wireless technology enable cyber-physical systems to automate solid waste management, which will revolutionize the industry. This work presents a comprehensive study on the evolution of automation approaches in solid waste management systems. This study is enhanced by dissecting the available literature in solid waste management with Radio Frequency Identification (RFID), Wireless Sensor Networks (WSN), and Internet of Things (IoT)-based approaches and analyzing each category with a typical architecture, respectively. In addition, various communication technologies adopted in the aforementioned categories are critically analyzed to identify the best choice for the deployment of trash bins. From the survey, it is inferred that IoT-based systems are superior to other design approaches, and LoRaWAN is identified as the preferred communication protocol for the automation of solid waste handling systems in urban areas. Furthermore, the critical open research issues on state-of-the-art solid waste handling systems are identified and future directions to address the same topic are suggested.

M-GRCT: A Dynamic Circular Economy Model for the Optimal Design of Waste Management Systems in Low-Income Municipalities

This article introduces M-GRCT, a circular economy decision support model for the design of recyclable waste management systems in low-income municipalities. The model allows for performing calculations on a set of two scenarios integrating a sociocultural dynamics assessment, this being a characteristic feature of this type of municipalities. The model also integrates the analysis of the remaining variables usually addressed in solid waste management schemes while considering topics such as reduction of the carbon footprint due to activities such as the transport of recyclable waste, the generation of leachates, the generation of greenhouse gases and the promotion of an increase in the number of associated recyclers and selective routes. The economic evaluation of the different implementation scenarios is supported by a dynamic tool called DATA4 (a macro-type array accompanied by two control panels programmed in Visual Basic and dashboards by Power BI). M-GRCT constitutes a tool for the promotion of good environmental practices and the identification of strategies for the promotion of local development mechanisms. Results provided by the model contrast with those obtained by traditional linear economy approaches. An illustrative example of the application of the M-GRCT model is shown. The model was used to simulate the municipal solid waste managing system of the municipality of Guateque (Colombia). The results show the importance of integrating both economic and environmental costs to optimally allocate governmental and private resources when the recycling rate is expected to increase in the next 10 years.

Biosorption of Cr(VI) Using Cellulose Nanocrystals Isolated from the Waterless Pulping of Waste Cotton Cloths with Supercritical CO2: Isothermal, Kinetics, and Thermodynamics Studies

In the present study, supercritical carbon dioxide (scCO₂) was utilized as a waterless pulping for the isolation of cellulose nanocrystals (CNCs) from waste cotton cloths (WCCs). The isolation of CNCs from the scCO₂-treated WCCs’ fiber was carried out using sulphuric acid hydrolysis. The morphological and physicochemical properties analyses showed that the CNCs isolated from the WCCs had a rod-like structure, porous surface, were crystalline, and had a length of 100.03 ± 1.15 nm and a width of 7.92 ± 0.53 nm. Moreover, CNCs isolated from WCCs had a large specific surface area and a negative surface area with uniform nano-size particles. The CNCs isolated from WCCs were utilized as an adsorbent for the hexavalent chromium [Cr(VI)] removal from aqueous solution with varying parameters, such as treatment time, adsorbent doses, pH, and temperature. It was found that the CNCs isolated from the WCCs were a bio-sorbent for the Cr(VI) removal. The maximum Cr(VI) removal was determined to be 96.97% at pH 2, 1.5 g/L of adsorbent doses, the temperature of 60 °C, and the treatment time of 30 min. The adsorption behavior of CNCs for Cr(VI) removal was determined using isothermal, kinetics, and thermodynamics properties analyses. The findings of the present study revealed that CNCs isolated from the WCCs could be utilized as a bio-sorbent for Cr(VI) removal.

New approach for selecting a suitable recycling collection program for recovered paper and pulp recyclables using AHP-TOPSIS techniques

In the past decade, the use of multiple-criteria decision analysis technology has dramatically increased in solving complex real-world problems in solid waste management. Likewise, many municipalities have paid attention to finding feasible solutions for disposal and recycling of solid waste due to the increase in waste generation rates worldwide. Therefore, policy-makers must determine which recycling program to be implemented among various recycling program options. In this paper, a new approach to select a recycling program for recovered paper and pulp recyclables was proposed using analytic hierarchy process-Technique for Order Preference by Similarity to Ideal Solution (AHP-TOPSIS) techniques. A set of essential parameters of the decision-making system were identified, and a numerical case to illustrate the procedure was conducted. Our findings show very encouraging results to use a combined model between AHP and TOPSIS to select a suitable recycling program for different recovered recyclable materials.

Data mining and knowledge discovery in databases for urban solid waste management: A scientific literature review

The processes related to solid waste management (SWM) are being revised as new technologies emerge and are applied in the area to achieve greater environmental, social and economic sustainability for society. To achieve our goal, two robust review protocols (Population, Intervention, Comparison, Outcome, and Context (PICOC) and Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA)) were used to systematically analyze 62 documents extracted from the Web of Science database to identify the main techniques and tools for Knowledge Discovery in Databases (KDD) and Data Mining (DM) as applied to SWM and explore the technological potential to optimize the stages of collecting and transporting waste. Moreover, it was possible to analyze the main challenges and opportunities of KDD and DM for SWM. The results show that the most used tools for SWM are MATLAB (29.7%) and GIS (13.5%), whereas the most used techniques are Artificial Neural Networks (35.8%), Linear Regression (16.0%) and Support Vector Machine (12.3%). In addition, 15.3% of the studies were conducted with data from China, 11.1% from India and 9.7% of the studies analyzed and compared data from several other countries. Furthermore, the research showed that the main challenges in the field of study are related to the collection and treatment of data, whereas the opportunities appear to be linked mainly to the impact on the pillars of sustainable development. Thus, this study portrays important issues associated with the use of KDD and DM for optimal SWM and has the potential to assist and direct researchers and field professionals in future studies.

Life-Cycle Assessment of a Regulatory Compliant U.S. Municipal Solid Waste Landfill

Landfills receive over half of all U.S. municipal solid waste (MSW) and are the third largest source of anthropogenic methane emissions. Life-cycle assessment (LCA) of landfills is complicated by the long duration of waste disposal, gas generation and control, and the time over which the engineered infrastructure must perform. The objective of this study is to develop an LCA model for a representative U.S. MSW landfill that is responsive to landfill size, regulatory thresholds for landfill gas (LFG) collection and control, practices for LFG management (i.e., passive venting, flare, combustion for energy recovery), and four alternative schedules for LFG collection well installation. Material production required for construction and operation contributes 68-75% to toxicity impacts, while LFG emissions contribute 50-99% to global warming, ozone depletion, and smog impacts. The current non-methane organic compound regulatory threshold (34 Mg yr^-1) reduces methane emissions by <7% relative to the former threshold (50 Mg yr^-1). Requiring landfills to continue collecting LFG until the flow rate is <10 m³ min^-1 reduces emissions by 20-52%, depending on the waste decay rate. In general, for landfills already required to collect gas, collecting gas longer is more important than collecting gas earlier to reduce methane emissions.

Provision of extended producer responsibility system for products packaging: A case study of Iran

A powerful legal tool in evolving solid waste management (SWM) systems is extended producer responsibility (EPR). It is a mechanism that shifts the responsibility of a product to manufacturers/importers at the 'end-of-life' stage. Yet, implementation of the EPR concept has faced difficulties in developing countries. In Iran, as one such country, the principle of EPR system was issued in executive regulation of SWM in 2005, however, so far, it has been limited to a voluntary scheme. The problem merits further investigation. Therefore, this study aims to shed light on the obstacles in the path of developing EPR system for product packaging. The research examines the current SWM systems in four functional classified frameworks: legal, institutional, financial and technical. The strengths, weaknesses, opportunities and threats of the system are elaborated through semi-structured interviews with a senior executive in the Ministry of Interior (MoI). Then, viable methods to increase resource efficiency and sustainable waste treatment are suggested. The change in the financing mechanism in the Budget Law 2020 forces the manufacturers/importers of products containing recyclable components to pay the revenue from one in 1000 products to MoI for developing recycling facilities and incinerators through partnerships with the private sector. This new strategy would promote proper management of product packaging, create more jobs and a market for international cooperation. However, poor source-separation of wet/dry waste, informal sector activities, exclusive focus on the economic aspect of waste management, lack of expertise and public awareness campaigns are the barriers in this regard.

Prioritizing health, safety and environmental hazards by integrating risk assessment and analytic hierarchy process techniques in solid waste management facilities

The aim of this research was to assess and prioritize risk levels of health, safety, and environmental (HSE) hazards in solid waste management facilities of Tehran, Iran. The risk of HSE hazards was assessed using Fine-Kinney and environmental failure mode and effects analysis (EFMEA) methods and then the high-risk hazards were prioritized for implementing corrective actions by analytic hierarchy process (AHP) considering six criteria of (1) probability of occurrence, (2) severity of consequences, (3) simultaneous HSE effects, and (4-6) feasibility, effectiveness, and cost of corrective actions. A total number of 485 HSE hazards were identified, of which 78% were health and safety hazards and 22% were environmental hazards. The proportions of the transfer and transport, material recovery and composting facilities and landfill sites in the identified hazards were 21%, 38%, and 41%, respectively. Based on the AHP method, the leading hazards in the transfer and transport, material recovery and composting facilities, and landfill sites were exposure to bioaerosol in carwash facilities, exposure to bioaerosols and odor/volatile organic compounds (VOCs) in manual waste separation, and leachate spills in the former landfill site, respectively. This study showed that the hybrid method was an appropriate and reliable tool to prioritize HSE hazards.

Understanding the Effect of Internal and External Factors on Households' Willingness to Sort Waste in Dammam City, Saudi Arabia

The acceleration of growth in the population in Saudi Arabia and the increase in municipal solid waste generation have caused a problem in Dammam city: an increase in solid waste production. Therefore, solid waste sorting is an important practice of municipal solid waste management. The main objectives in this research are understanding the effect of internal and external factors on household willingness in sorting waste in Dammam city and studying the attempts to construct a theoretical research model by adding market incentives, government facilitators, and awareness into the popular planned behaviour theory to explain residents' waste sorting intentions. The data collection and analysis are based on the questionnaire study, which is based on the questionnaire survey data from 450 households in Dammam. This study revealed that social influence significantly predicts households' willingness to sort and recycle, that is, to promote recycling. Additionally, the variable social influence has a significant but low influence on households' willingness to sort and recycle. The result of the structural equation model shows that perceived behavioural control significantly predicts households' willingness to sort and recycle waste. This finding is consistent with the theoretical expectation. Therefore, this research shows that attitude, social influence, perceived behavioural control, market incentives, government facilitators and awareness positively and significantly affect residents' waste sorting intentions. Additionally, this research corroborates the discrepancy between internal and external variables.

Consequences of COVID-19 pandemic on solid waste management: Scenarios pertaining to developing countries

Undoubtedly the most searched and spoken word of last year is coronavirus disease 2019 (COVID‐19), which initially originated in Wuhan, China near the end of 2019. COVID‐19 is a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). Albeit almost all countries shut down their borders to prevent rapid spread of the virus. However, the number of cases continues to increase in developing countries at a faster rate due to community and cluster transmission. The severity of this epidemic made it a pandemic as it progressed to over 200 countries. The World Health Organization (WHO), governments, and national disease control and prevention units worked together to break the chain and are working to contain the catastrophic impact of COVID‐19. They formulated and recommended various guidelines like social distancing, frequent hand washing, and social distancing to inhibit the spread of the virus. WHO also advised that the general population and medical personnel wear face masks, face shields, gloves, and aprons. As a result, this waste category has substantially increased and, if not disposed of properly, may cause the infection or help to catalyze COVID‐19. In developing countries, poor solid waste management may aggravate chances of spreading COVID‐19. Sustainable solid waste management is a critical parameter for the health, wellbeing, and development of society. The measures adopted to contain and restrict the spread of the COVID‐19 pandemic and minimize the degrees of freedom in commercial events affected solid waste management considerably. During this crucial time, the services provided by waste management agencies and personnel are invaluable and these services help to prevent the improper disposal of waste, which may lead to health risks due to the spread of COVID. COVID‐19 is a new and novel virus and experts are learning more about it overtime and with evolving science. This review paper provides insight into different types of solid wastes generated during the pandemic, their consequences, and the implication of various policies.

Facemasks: A Looming Microplastic Crisis

Single-use disposable facemasks have been used as a preventive measure against the ongoing COVID-19 pandemic. However, many researchers have found evidence that these facemasks are being dumped into lakes, rivers, and open garbage dumps. Facemasks have the potential of releasing microplastic fibers into the environment; a phenomenon that has been poorly investigated. Moreover, microplastic fibers composed of plastics have the potential of affecting the flora and fauna of many ecosystems. In this preliminary study, we investigate how many microplastic fibers had been released to the water by KF-AD, KF94, surgical, and FFP1 standard facemasks, which are the most widely available facemask standards in South Korea. The waterbody in our research was mechanically agitated for 24, 48, and 72 h. Findings showed that most of the layers of facemasks are composed of polypropylene. The surgical and KF94 standard facemasks released the highest number of microplastic fibers. Furthermore, under our research conditions, a single facemask can release at least 47 microplastic fibers per day (e.g., KF-AD standard mask), which can lead to the release of at least 1381 million microplastic fibers per day in total in South Korea if 70% of the urban population uses a single mask every day. Moreover, the released microplastic fibers significantly increased when the agitation time extended from 24 to 48 h. This finding suggests that the number of released microplastic fibers is likely to increase drastically.

Performance Analysis of IoT and Long-Range Radio-Based Sensor Node and Gateway Architecture for Solid Waste Management

Long-range radio (LoRa) communication is a widespread communication protocol that offers long range transmission and low data rates with minimum power consumption. In the context of solid waste management, only a low amount of data needs to be sent to the remote server. With this advantage, we proposed architecture for designing and developing a customized sensor node and gateway based on LoRa technology for realizing the filling level of the bins with minimal energy consumption. We evaluated the energy consumption of the proposed architecture by simulating it on the Framework for LoRa (FLoRa) simulation by varying distinct fundamental parameters of LoRa communication. This paper also provides the distinct evaluation metrics of the the long-range data rate, time on-air (ToA), LoRa sensitivity, link budget, and battery life of sensor node. Finally, the paper concludes with a real-time experimental setup, where we can receive the sensor data on the cloud server with a customized sensor node and gateway.

Recycling Waste Cotton Cloths for the Isolation of Cellulose Nanocrystals: A Sustainable Approach

There is an interest in the sustainable utilization of waste cotton cloths because of their enormous volume of generation and high cellulose content. Waste cotton cloths generated are disposed of in a landfill, which causes environmental pollution and leads to the waste of useful resources. In the present study, cellulose nanocrystals (CNCs) were isolated from waste cotton cloths collected from a landfill. The waste cotton cloths collected from the landfill were sterilized and cleaned using supercritical CO₂ (scCO₂) technology. The cellulose was extracted from scCO₂-treated waste cotton cloths using alkaline pulping and bleaching processes. Subsequently, the CNCs were isolated using the H₂SO₄ hydrolysis of cellulose. The isolated CNCs were analyzed to determine the morphological, chemical, thermal, and physical properties with various analytical methods, including attenuated total reflection-Fourier transform-infrared spectroscopy (ATR-FTIR), field-emission scanning electron microscopy (FE-SEM), energy-filtered transmission electron microscopy (EF-TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The results showed that the isolated CNCs had a needle-like structure with a length and diameter of 10–30 and 2–6 nm, respectively, and an aspect ratio of 5–15, respectively. Additionally, the isolated CNCs had a high crystallinity index with a good thermal stability. The findings of the present study revealed the potential of recycling waste cotton cloths to produce a value-added product.

Consequences of COVID-19 pandemic on solid waste management: Scenarios pertaining to developing countries

Undoubtedly the most searched and spoken word of last year is coronavirus disease 2019 (COVID-19), which initially originated in Wuhan, China near the end of 2019. COVID-19 is a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Albeit almost all countries shut down their borders to prevent rapid spread of the virus. However, the number of cases continues to increase in developing countries at a faster rate due to community and cluster transmission. The severity of this epidemic made it a pandemic as it progressed to over 200 countries. The World Health Organization (WHO), governments, and national disease control and prevention units worked together to break the chain and are working to contain the catastrophic impact of COVID-19. They formulated and recommended various guidelines like social distancing, frequent hand washing, and social distancing to inhibit the spread of the virus. WHO also advised that the general population and medical personnel wear face masks, face shields, gloves, and aprons. As a result, this waste category has substantially increased and, if not disposed of properly, may cause the infection or help to catalyze COVID-19. In developing countries, poor solid waste management may aggravate chances of spreading COVID-19. Sustainable solid waste management is a critical parameter for the health, wellbeing, and development of society. The measures adopted to contain and restrict the spread of the COVID-19 pandemic and minimize the degrees of freedom in commercial events affected solid waste management considerably. During this crucial time, the services provided by waste management agencies and personnel are invaluable and these services help to prevent the improper disposal of waste, which may lead to health risks due to the spread of COVID. COVID-19 is a new and novel virus and experts are learning more about it overtime and with evolving science. This review paper provides insight into different types of solid wastes generated during the pandemic, their consequences, and the implication of various policies.

Partnerships for sustainable cities as options for improving solid waste management in Nairobi city

Partnerships as enshrined in policies are vital for achieving sustainable cities under the Sustainable Development Goals (SDGs). Indeed the SDGs recognize the importance of partnerships in solid waste management (SWM) as a way of developing workable and reliable waste management systems. SWM in Nairobi city continues to be a great challenge, and poor practices threaten environmental and public health. Ineffective waste management in Nairobi city has been linked to inefficient policy implementation and enforcement by different stakeholders. To effectively address the challenge of sustainable waste management in Nairobi city, amalgamation of strategies amongst several segments, including stakeholders, private and public sectors (formal and informal), non-governmental organizations and communities, is important, through partnerships to implement improved policies, in terms of capacity, financial prudence, and technical and institutional factors. The paper seeks to analyse existing policy framework on SWM and its effectiveness in addressing SWM in Nairobi city. The study is based on a descriptive research design which involved interrogating the stakeholders included in the implementation of the policy frameworks in place. Data were acquired through semi-structured questionnaires administered to 385 respondents and interviews with 10 key informants. The theoretical framework is based on institutional theory and capacity building theories that expound the gaps in policy implementation and the role of partnerships. Policies in SWM should be interlinked for sustainable cities.

Tariff determination for municipal waste management power projects in Pakistan

Waste management is an emerging focus in Pakistan. Specifically, waste-to-energy (WtE) projects are conceived to obtain benefits from municipal waste collection in metropolitan cities. This study provides a brief background of WtE potential, waste collection statistics, type of generated wastes, and current measures to build the confidence of investors in WtE projects. In addition, a brief overview of government efforts for WtE and delineation of licensing requirements for power generation are discussed. The parameters laid down for the determination of tariffs for municipal waste management power projects and the cost accounted for each parameter are analyzed in detail. Similarly, this study deliberates on observations among stakeholders and compares Pakistan tariffs with those of neighboring countries.

Determinants of Public-Private Partnership Adoption in Solid Waste Management in Rural China

Rural solid waste management is a severe challenge in China. The Public-Private Partnership (PPP) is an effective method for rural solid waste management. However, policy efforts aimed at stimulating the adoption of PPP in rural solid waste management have been limited in their success. This study aims to empirically investigate the determinants of rural solid waste management PPP adoption in China. First, this study builds a theoretical model that consists of factors related to the institutional environment and market and proposes theoretical hypotheses. Then, using the balanced provincial panel data of 150 samples from 2015 to 2019, this study applies various count regression models and truncated regression models to empirically test the theoretical hypotheses. The results show that provinces with higher fiscal transparency, financial burdens, and market demand tend to adopt more PPP, while provinces with lower per capita GDP and market openness index ratings have a stronger motivation to initiate more PPP. In contrast, investment institutional environment factors have no impact on PPP adoption. To stimulate the development of PPP in rural solid waste management, this study proposed that a good-governed government and a strong market demand are critical foundations, and also a debt-risk prevention and evaluation system should be established to avoid local debt risks resulting from over-adoption of PPP.

Analytical Methodology for the Identification of Critical Zones on the Generation of Solid Waste in Large Urban Areas

One of the main environmental issues to address in large urban areas is the ever-increasing generation of municipal solid waste (MSW) and the need to manage it properly. Despite significant efforts having been made to implement comprehensive solid waste management systems, current management methods often do not provide sustainable alternatives which ensure the reduction of solid waste generation. This paper presents an analytical methodology that employs a combination of geographic information system techniques (GIS) along with statistical and numerical optimization methods to evaluate solid waste generation in large urban areas. The methodology was successfully applied to evaluate MSW generation in different exclusive service areas (ASES) of the city of Bogotá (Colombia). The results of the analysis on the solid waste generation data in each collection area in terms of its socioeconomic level are presented below. These socioeconomic levels are explained by defining different strata in terms of their purchasing power. The results demonstrate the usefulness of these GIS and numerical optimization techniques as a valuable complementary tool to analyze and design efficient and sustainable solid waste management systems.

Vermicomposting process for treating animal slurry in Latin American rural areas

The management of animal slurry is a big issue in low-income rural areas worldwide. Bolivia suffers this issue related to collection, treatment and final disposal since the main solution applied is the open dumping. The aim of this study is to introduce a feasible treatment of animal slurry in the rural area of Carmen Pampa, where about 670 kg of dung are produced per day and disposed of in open areas. The objective is the improvement of the environmental sustainability and human health, providing an alternative solution for encouraging the circular economy. The study is focused on the vermicomposting process, a sustainable solution for low-income regions. The analysis was conducted in function of the earthworm breeds used locally ( Eisenia fetida and Lumbricus terrestris) and the application of activated bacteria (AB) for improving the process. The mass loss, the treatment time, and the growing rate of the earthworms were analyzed. The results suggest that the different breed of the worms allows gaining up to 19 days, while the use of the AB allows saving about 30 days. Moreover, the vermicomposting process reduced the mass of the slurry of about 65% for the swine's dung and the bovine's dung, and 90% of the hens' dung. Finally, experimental evidence shows that the growing rate of the E. fetida is higher than the L. terrestris (F[1,8] = 78, p < 0.05), with an average of about 193%. The data obtained could be of interest for other stakeholders who live in similar environmental, climatic, and economic conditions for improving sustainability.

Waste Mismanagement in Developing Countries: A Review of Global Issues

Environmental contamination due to solid waste mismanagement is a global issue. Open dumping and open burning are the main implemented waste treatment and final disposal systems, mainly visible in low-income countries. This paper reviews the main impacts due to waste mismanagement in developing countries, focusing on environmental contamination and social issues. The activity of the informal sector in developing cities was also reviewed, focusing on the main health risks due to waste scavenging. Results reported that the environmental impacts are pervasive worldwide: marine litter, air, soil and water contamination, and the direct interaction of waste pickers with hazardous waste are the most important issues. Many reviews were published in the scientific literature about specific waste streams, in order to quantify its effect on the environment. This narrative literature review assessed global issues due to different waste fractions showing how several sources of pollution are affecting the environment, population health, and sustainable development. The results and case studies presented can be of reference for scholars and stakeholders for quantifying the comprehensive impacts and for planning integrated solid waste collection and treatment systems, for improving sustainability at a global level.

Impact of Swachh Bharat Abhiyan on Residents of Cochin Corporation

Context:

Environmental sanitation is a major public health issue in India. Sustainable Development Goal 6 envisages the accessibility of safe water and sanitation throughout the world. Swachh Bharat Abhiyan (SBA), a national cleanliness campaign established by the Government of India in 2014, has six main objectives. It has crossed the half-way point of its intended implementation course.

Aims:

This study aims to assess the impact of SBA on the sanitation of Cochin Corporation and to identify factors associated with awareness and practice of SBA.

Settings and Design:

A cross-sectional study among residents of Cochin Corporation.

Materials and Methods:

Semi-structured questionnaire was used to measure awareness, practice, and impact of SBA. Three divisions were selected purposively. A score was assigned for knowledge and impact assessment questions and was classified into three categories.

Statistical Analysis Used:

Descriptive statistics using frequencies and percentages were done. Chi-square test was used to test differences between proportions.

Results:

Thirty percent had no awareness regarding SBA and 42% had minimal awareness regarding the program and its objectives. Only 24% responded that SBA had a good impact on the overall sanitation of the community. The impact of SBA was significantly associated with socioeconomic status. The study revealed the major sanitary concern of the community to be the disposal of solid waste.

Conclusion:

The SBA did not have a significant impact on Cochin population due to existing good sanitation. Solid waste disposal is still a concern of the community. As far as, Kerala is concerned, it appears that the primary focus of SBA should be on Municipal Solid Waste Management.

Municipal solid waste management: Constraints and opportunities to improve capacity of local government authorities of Phnom Penh Capital

Solid waste management is a challenge for Phnom Penh city owing to the increasing volume of waste produced and insufficient collection capacity. Sustainable management is required in response to continuing population growth and urbanisation. This article aims to examine the status and constraints of solid waste management in Phnom Penh and discuss the performance of local government authorities to propose possible mechanisms and strategies to improve the system. Data were collected through literature reviews, key informant interviews and focus group discussions with the local government authorities. Six performance measures were used as assessment variables, including technical, environmental, institutional and organisational, financial and economic, social and cultural, and policy and legal factors. Limited institutional capacity and performance are the consequence of insufficient decentralisation power and allocation of budget and workforce for promoting technological and environmentally sustainable practices. Lack of cooperation and coordination among relevant agencies led to their unwillingness to participate in management performance. A decentralisation and provision of management services in the public-private partnership would enable operational procedures that enhance accountability, transparency, efficiency, and productivity at the local level.

Feasibility of biogas and energy generation from poultry manure in Brazil

The aim of the present study is to experimentally measure the volume and composition of biogas produced from the anaerobic biodigestion of laying-hen manure from poultry farms in Itanhandu-MG, Brazil, so that the biogas can be used to generate energy. Two experiments (E1 and E2) were used to characterise the biogas quantities and compositions at room temperature and at a controlled temperature of 36 °C, respectively. The biogas production and calculated net power from the exploitation of biogas energy were compared with the results obtained from methods proposed by the Environmental Company of the State of São Paulo (CETESB, an acronym in Portuguese) using the 'Biogas: Generation and energy use - effluent and rural waste' software 1.0, Brasília-DF, Brazil. In addition, after a time equal to the hydraulic retention time subsequent to biodigester loading, the parameters were analysed and correlated with the organic matter content in the substrates. The effluents were subsequently compared with verify the degree of degradability. The biogas volumes were estimated to be 0.143 m³ kg VTS^-1 for E1 and 0.283 m³ kg VTS^-1 for E2. If the poultry farm considered in this case study uses manure to generate energy, then the estimated energy generation based on the data from experiments E1 and E2 will result in net energy values of 683 MW h y^-1 and 27,160 MW h y^-1, given 620 MW h y^-1 for sludge heating in E2. The energy production values from the simulations of the E1 and E2 experiments did not demonstrate economic viability under the studied conditions.

Greenhouse gas contribution of municipal solid waste collection: A case study in the city of Istanbul, Turkey

This article estimates greenhouse gas emissions and global warming factors resulting from collection of municipal solid waste to the transfer stations or landfills in Istanbul for the year of 2015. The aim of this study is to quantify and compare diesel fuel consumption and estimate the greenhouse gas emissions and global warming factors associated with municipal solid waste collection of the 39 districts of Istanbul. Each district's greenhouse gas emissions resulting from the provision and combustion of diesel fuel was estimated by considering the number of collection trips and distances to municipal solid waste facilities. The estimated greenhouse gases and global warming factors for the districts varied from 61.2 to 2759.1 t CO₂-eq and from 4.60 to 15.20 kg CO₂-eq t^-1, respectively. The total greenhouse gas emission was estimated as 46.4E3 t CO₂-eq. Lastly, the collection data from the districts was used to parameterise a collection model that can be used to estimate fuel consumption associated with municipal solid waste collection. This mechanistic model can then be used to predict future fuel consumption and greenhouse gas emissions associated with municipal solid waste collection based on projected population, waste generation, and distance to transfer stations and landfills. The greenhouse gas emissions can be reduced by decreasing the trip numbers and trip distances, building more transfer stations around the city, and making sure that the collection trucks are full in each trip.

Integration of informal recycling sector in Brazil and the case of Sorocaba City

Catadores are people who collect and sell materials that can be recycled. This activity has been done informally in many countries for years. Recently, a recognition process has begun for the informal recycling sector, with public and private initiatives. In Brazil, catadores started out associating with each other in co-operatives in the 1980s. In 2010, the Solid Waste National Policy was approved, promoting the inclusion of theses co-operatives in the formal waste management system. However, only in 25 out of 5670 Brazilian municipalities have hired co-operatives as Private Service Providers. The integration of the informal sector has contributed with social, economic and environmental benefits; income generation, reduction of poverty and resource preservation are highlights. Although there was a legal progress, there are great challenges for various actors involved. This paper aims to diagnose the informal recycling sector, emphasizing the integration process that has happened in Brazil. For this, a substantial literature review and a case study were conducted, applying the tool 'InteRa' to the case of Sorocaba. The case showed that it is possible to improve the integration of catadores in the formal waste management system. The co-operatives achieve recycling rates of 2%, higher than the official national rate of 1%. However, we estimate that autonomous pickers increase total recycling in Sorocaba to 9%, still short of the 25% target via source segregation. Therefore, continuing the integration process will benefit both the pickers, and also the municipality through savings on landfill costs.

Assessment of environmental policy implementation in solid waste management in Kathmandu, Nepal

In Nepal, full-fledged environmental legislation was rare before the democratic constitution of 1990. The first law covering the environment and sustainability was the Environment Protection Act 1997. While the Solid Waste Act was introduced in 1987, the problem of solid waste management still surfaces in Kathmandu. In order to understand the bedrock of this unrelenting failure in solid waste management, the manuscript digs deeper into policy implementation by dissecting solid waste rules, environmental legislations, relevant local laws, and solid waste management practices in Kathmandu, Nepal. A very rich field study that included surveys, interviews, site visits, and literature review provided the basis for the article. The study shows that volumes of new Nepalese rules are crafted without effective enforcement of their predecessors and there is a frequent power struggle between local government bodies and central authority in implementing the codes and allocating resources in solid waste management. The study concludes that Kathmandu does not require any new instrument to address solid waste problems; instead, it needs creation of local resources, execution of local codes, and commitment from central government to allow free exercise of these policies.

Multi-criteria decision making to support waste management: A critical review of current practices and methods

Solid waste management is a complex domain involving the interaction of several dimensions; thus, its analysis and control impose continuous challenges for decision makers. In this context, multi-criteria decision-making models have become important and convenient supporting tools for solid waste management because they can handle problems involving multiple dimensions and conflicting criteria. However, the selection of the multi-criteria decision-making method is a hard task since there are several multi-criteria decision-making approaches, each one with a large number of variants whose applicability depends on information availability and the aim of the study. Therefore, to support researchers and decision makers, the objectives of this article are to present a literature review of multi-criteria decision-making applications used in solid waste management, offer a critical assessment of the current practices, and provide suggestions for future works. A brief review of fundamental concepts on this topic is first provided, followed by the analysis of 260 articles related to the application of multi-criteria decision making in solid waste management. These studies were investigated in terms of the methodology, including specific steps such as normalisation, weighting, and sensitivity analysis. In addition, information related to waste type, the study objective, and aspects considered was recorded. From the articles analysed it is noted that studies using multi-criteria decision making in solid waste management are predominantly addressed to problems related to municipal solid waste involving facility location or management strategy.

Characterization of municipal solid waste in high-altitude sub-tropical regions

Solid waste management (SWM) is one of the most challenging issues owing to lack of authentic data on different elements of SWM, namely, storage, collection, transportation, separation, processing and disposal. This study presents an assessment of existing status of SWM in conjunction with municipal solid waste (MSW) generation rates, physical and chemical characterization of MSW in high-altitude sub-tropical regions. Weighing of empty and fully loaded trucks per trip revealed total quantity of MSW collected. The average efficiency of MSW collection was 70%. From the baseline data, it is inferred that the population and MSW generation rates are not co-related. The collected MSW included biodegradables (organic wastes), paper, plastic, glass, ceramics, metals, inert materials, ash and debris. The data analysis indicated that the biodegradable components dominate the characterization at 54.83% followed by inert, ash and debris at 21.06%, paper at 8.77%, plastic at 8.18%, glass and ceramics at 4.45% and metals at 2.71%. Statistical measures were also applied and 90% confidence interval (CI) was generated for the characterization data measuring its statistical significance.

Utilization of ferrochrome wastes such as ferrochrome ash and ferrochrome slag in concrete manufacturing

Solid waste management is one of the subjects essentially addressing the current interest today. Due to the scarcity of land filling area, utilization of wastes in the construction sector has become an attractive proposition for disposal. Ferrochrome ash (FA) is a dust obtained as a waste material from the gas cleaning plant of Ferro alloy industries. It possesses the chemical requirements of granulated slag material used for the manufacture of Portland cement. Ferrochrome slag (FS) is another residue that is obtained as a solid waste by the smelting process during the production of stainless steel in Ferroalloy industries. FS possesses the required engineering properties of coarse aggregates. The possibility of using FA with lime for partial replacement of ordinary Portland cement (OPC) and FS for total replacement of natural coarse aggregates is explored in this research. The combined effect of FA with lime and FS-addition on the properties of concrete, such as workability, compressive strength, flexural strength, splitting tensile strength and sorptivity, were studied. Results of investigation revealed improvement in strength and durability properties of concrete on inclusion of FA and FS. Concrete mix containing 40% FA with 7% lime (replacing 47% OPC) and100% of FS (replacing 100% natural coarse aggregate) achieved the properties of normal concrete or even better properties at all ages. The results were confirmed by microscopic study such as X-ray diffraction and petrography examination. Environmental compatibility of concrete containing FA and FS was verified by the toxicity characteristic leaching procedure test.

Public Space, Public Waste, and the Right to the City

I draw on my experiences as an organizer with a waste-pickers collective, Kagad Kach Patra Kashtakari Panchayat in Pune, India, to reflect on the power dynamics in control of public space. The Pune Municipal Corporation (PMC), a public body, has used public resources to facilitate and enable accumulation by private companies, who have not been able to produce what they had committed to in the processing of waste. The waste pickers, in alliance with affected village-based land agitation committees, have mobilized against the dumping that is ruining their way of life, environments, and health, and are fighting for their own integration into waste value chains. The article uses the frame of David Harvey's(1) "right to the city"; a key part of the mobilizing work with waste pickers has been Freirean conscientization methods to spread awareness of the economic importance, to the city and to the planet, of waste recycling.

A tale of five cities: Using recycling frameworks to analyse inclusive recycling performance

'Recycling' is a source of much confusion, particularly when comparing solid waste systems in high-income countries with those in low- and middle-income countries. Few analysts can explain why the performance and structure of recycling appears to be so different in rich countries from poor ones, nor why well-meaning efforts to implement recycling so often fail. The analysis of policy drivers, and the Integrated Sustainable Waste Management (ISWM) framework, come close to an explanation.This article builds on these earlier works, focusing in on five cities profiled in the 2010 UN-Habitat publication (Scheinberg A, Wilson DC and Rodic L (2010) Solid Waste Management in the World's Cities. UN-Habitat's Third Global Report on the State of Water and Sanitation in the World's Cities. Newcastle-on-Tyne, UK: Earthscan Publications). Data from these cities and others provides the basis for developing a new tool to analyse inclusive recycling performance. The points of departure are the institutional and economic relationships between the service chain, the public obligation to remove waste, pollution, and other forms of disvalue, and the value chain, a system of private enterprises trading valuable materials and providing markets for recyclables. The methodological innovation is to use flows of materials and money as indicators of institutional relationships, and is an extension of process flow diagramming.The authors are using the term 'recycling framework analysis' to describe this new form of institutional analysis. The diagrams increase our understanding of the factors that contribute to high-performance inclusive recycling. By focusing on institutional relationships, the article seeks to improve analysis, planning, and ultimately, outcomes, of recycling interventions.

How to assess solid waste management in armed conflicts? A new methodology applied to the Gaza Strip, Palestine

We have developed a new methodology for assessing solid waste management in a situation of armed conflict. This methodology is composed of six phases with specific activities, and suggested methods and tools. The collection, haulage, and disposal of waste in low- and middle-income countries is so complicated and expensive task for municipalities, owing to several challenges involved, that some waste is left in illegal dumps. Armed conflicts bring further constraints, such as instability, the sudden increase in violence, and difficulty in supplying equipment and spare parts: planning is very difficult and several projects aimed at improving the situation have failed. The methodology was validated in the Gaza Strip, where the geopolitical situation heavily affects natural resources. We collected information in a holistic way, crosschecked, and discussed it with local experts, practitioners, and authorities. We estimated that in 2011 only 1300 tonne day(-1) were transported to the three disposal sites, out of a production exceeding 1700. Recycling was very limited, while the composting capacity was 3.5 tonnes day(-1), but increasing. We carefully assessed system elements and their interaction. We identified the challenges, and developed possible solutions to increase system effectiveness and robustness. The case study demonstrated that our methodology is flexible and adaptable to the context, thus it could be applied in other areas to improve the humanitarian response in similar situations.

Multitrait plant growth promoting (PGP) rhizobacterial isolates from Brassica juncea rhizosphere : Keratin degradation and growth promotion

Plant growth promoting (PGP) rhizobacteria, a beneficial microbe colonizing plant roots, enhanced crop productivity and offers an attractive way to replace chemical fertilizers, pesticides, and supplements. The keratinous waste which comprises feathers, hairs, nails, skin and wool creates problem of solid waste management due to presence of highly recalcitrant keratin. The multi traits rhizobacteria effective to remove both keratine from the environment by producing keratinase enzyme and to eradicate the chemical fertilizer by providing different PGP activity is novel achievement. In the present study, the effective PM₂ strain of PGPR was isolated from rhizospheric soil of mustard (Brassica juncea) field, Pantnagar and they were identified on the basis of different biochemical tests as belonging to Bacillus genera. Different plant growth promoting activity, feather degradation and keratinolytic activity was performed and found very effective toward all the parameters. Furthermore, the efficient strain PM₂ was identified on the basis of 16s rRNA sequencing and confirmed as Bacillus cereus. The strain PM₂ might be used efficiently for keratinous waste management and PGP activity. Therefore, the present study suggests that Bacillus cereus have multi traits activity which extremely useful for different PGP activity and biotechnological process involving keratin hydrolysis, feather biodegradation or in the leather industry.