Climate co-benefits of energy recovery from landfill gas in developing Asian cities: a case study in Bangkok

Life cycle assessment of municipal solid waste generated from hilly cities in India - A case study

Improper disposal of waste poses a grave environmental threat, contributing to pollution of air, water, and soil. It is necessary to address this issue in order to mitigate the adverse effects of solid waste on both the environment and public health. In many developing nations, municipal authorities of bigger cities are enduring significant challenges in proper management of waste. The present study evaluates the impacts of various waste management alternative scenarios for environmental impacts for the selected study locations using Life Cycle Assessment (LCA) methodology. The methodology comprised of five different scenarios of waste management including an existing baseline scenario. In this context, the environmental impact categories analyzed were Global Warming potential (GWP), Acidification potential (AP), Eutrophication potential (EP) and Human Toxicity potential (HTP). The results indicated that amongst all the proposed scenarios, Scenario 1 and 4 exhibited the maximum and minimum environmental impacts respectively. The study revealed that least greenhouse gas emissions, acidification potential, eutrophication potential and human toxicity potential were comparatively lesser for scenario 4 varying from 5.65 to 11.36 kg CO2eq t-1; 1.24-3.345 kg SO2eq t-1, EP 0.19-0.68 kg PO4eq t-1, and 0.35-4.22 kg 1,4-DBeq t-1 respectively. Further, a sensitivity analysis was also performed to evaluate the influence of recycling rate of valuable resources in all the considered scenarios. The sensitivity analysis indicated an inversely proportional relation between change in recycling rate and total environmental burdens.

Municipal solid waste treatment for bioenergy and resource production: Potential technologies, techno-economic-environmental aspects and implications of membrane-based recovery

World estimated municipal solid waste generating at an alarming rate and its disposal is a severe concern of today's world. It is equivalent to 0.79 kg/d per person footprint and causing climate change; health hazards and other environmental issues which need attention on an urgent basis. Waste to energy (WTE) considers as an alternative renewable energy potential to recover energy from waste and reduce the global waste problems. WTE reduced the burden on fossil fuels for energy generation, waste volumes, environmental, and greenhouse gases emissions. This critical review aims to evaluate the source of solid waste generation and the possible routes of waste management such as biological landfill and thermal treatment (Incineration, pyrolysis, and gasification). Moreover, a comparative evaluation of different technologies was reviewed in terms of economic and environmental aspects along with their limitations and advantages. Critical literature revealed that gasification seemed to be the efficient route and environmentally sustainable. In addition, a framework for the gasification process, gasifier types, and selection of gasifiers for MSW was presented. The country-wise solutions recommendation was proposed for solid waste management with the least impact on the environment. Furthermore, key issues and potential perspectives that require urgent attention to facilitate global penetration are highlighted. Finally, practical implications of membrane and comparison membrane-based separation technology with other conventional technologies to recover bioenergy and resources were discussed. It is expected that this study will lead towards practical solution for future advancement in terms of economic and environmental concerns, and also provide economic feasibility and practical implications for global penetration.

Evaluation of the Effect of Deep Compost Application in the Areas around Vineyard Tree Trunks on Selected Soil Chemical Properties and the Vegetative Growth of the Vine

In the context of sustainability, viticulture will address issues related to soil fertility in the coming period. Greater attention will therefore be paid to replacing traditional manure-based fertilisers, such as farmyard manure, with new types of fertiliser in the form of composts, digestate, etc. Experience to date suggests that good-quality composts are not only a source of nutrients that the vines take from the soil each year, but also a source of organic matter. The application of compost and its subsequent decomposition in the soil profile can have a positive effect on the growth of the roots and above-ground parts of the vine. However, optimising the effects and action of compost is linked to determining the necessary doses and methods of application. The aim of this three-year study was to provide an overview of the results aimed at evaluating the effects of the application of compost (CO) and compost enriched with the addition of lignohumate (CO+L20), at a rate of 30 t·ha−1, in the areas around vineyard tree trunks on selected soil chemical properties and the vegetative growth of the vine (Vitis vinifera L.). The unfertilised variant (CWC) was used as a control. Each variant was established in three replicates that were 20 m long. Experimental measurements and evaluation were carried out in the period of 2018–2020 on two sites with different soil conditions (Lednice and Velké Bílovice) and two different grape varieties (Sauvignon Blanc and Pinot Gris). Meteorological data were continuously monitored during the period under review. Chemical properties of the soil samples of the three experimental variants were determined (e.g., content of organic carbon, humic acids, humic substances, humification rate, etc.). The evaluations that were carried out confirmed that the addition of organic matter in the form of composts to the soil in the CO and CO+L20 variants positively influenced the quality of organic matter. The organic carbon content increased by 56–139% in variants with deep compost application (CO, CO+L20) during the monitored period compared to the CWC, depending on the location. Similarly, the degree of humification increased by 70–84%, and the soil microbial biomass increased by 38–136% in the treated variants compared to the CWC. In addition to the dynamics of the changes in the chemical properties, the aim of the performed measurements was to evaluate the rate of the growth shoots, which was linked to the fertilizing effects of the applied compost in the experimental vineyard. At the site in Velké Bílovice, the total difference in the length of the shoots was higher in the CO by 2.6–4.6% and in the CO+L20 by 7.5–12.5% compared to the CWC. At the site in Lednice, the situation was similar, and the total difference in the length of the shoots was higher in the CO by 4.6–7.2% and in the CO+L20 by 5.3–13.2%. The results that were obtained may constitute an important basis for the management of organic fertilization on plots with different soil conditions and cultivated varieties in order to optimize the vegetative growth of the vine.

Sustainable Circular Economy for the Integration of Disadvantaged People: A Preliminary Study on the Reuse of Lithium-Ion Batteries

The circular economy is attracting the attention of governments and companies who recognize the importance of promoting a sustainable approach toward social and industrial development. The European Union requires EU State members to support a sustainable approach to improving the production and consumption of Waste Electrical and Electronic Equipment (WEEE). This paper supports the conceptualization of a sustainable circular economy model, proposing the reuse of lithium-ion batteries from WEEE. The aim is to define a circular economy-based production model for the reuse of waste lithium-ion batteries and support the inclusion of disadvantaged people in the recovery process, breaking the barriers of social discrimination. The activities introduced in this paper are part of a circular economy project for the social integration of disadvantaged people. In this paper, the preliminary results of the project are introduced, proposing a methodology for the disassembly of waste lithium-ion batteries. The disassembly line balancing proposed in this paper focuses on the need to include workers with physical, psychological, sensory, or intellectual limitations, as well as people experiencing communication difficulties. Future steps of the project will focus on the design of the assembly line to produce battery packs for pedal-assisted bicycles from the recovered lithium-ion cells.

Optimal Process Network for Integrated Solid Waste Management in Davao City, Philippines

Municipal solid waste management (MSWM) systems in developing countries adopt practices from developed countries to reduce their environmental burdens. However, several complex issues specific to developing countries hinder the full implementation of these practices. The future of MSWM in Davao City, Philippines, is envisaged as a notable example of the combination of new infrastructure and local MSWM practices. A linear programming model was developed, following material flow analysis and life cycle assessment, to design an optimal system for Davao City. The performance of the system was evaluated in terms of greenhouse gas emissions, energy and revenue generated, and the amount of landfill waste. The results show that the proposed system positively affects the environment compared to the current system, due to additional treatment options. However, the main allocation concern transitions from organic waste in the current system to plastic waste in future scenarios. Furthermore, the mitigation of greenhouse gas emissions and the extension of landfill life will be heavily influenced by trade-offs between sorting operations and the management of incinerated wastes with high calorific values. Therefore, plastic-waste-specific treatment options will be critical for future MSWM systems. The results herein underscore the need for sustainable MSWM in the study area, considering the region-specific conditions.

New perspectives for evaluating relative risks of African swine fever virus contamination in global feed ingredient supply chains

There are no published reports indicating that the African swine fever virus (ASFV) has been detected in feed ingredients or complete feed. This is primarily because there are only a few laboratories in the world that have the biosecurity and analytical capabilities of detecting ASFV in feed. Several in vitro studies have been conducted to evaluate ASFV concentration, viability and inactivation when ASFV was added to various feed ingredients and complete feed. These inoculation studies have shown that some feed matrices support virus survival longer than others and the reasons for this are unknown. Current analytical methodologies have significant limitations in sensitivity, repeatability, ability to detect viable virus particles and association with infectivity. As a result, interpretation of findings using various measures may lead to misleading conclusions. Because of analytical and technical challenges, as well as the lack of ASFV contamination data in feed supply chains, quantitative risk assessments have not been conducted. A few qualitative risk assessments have been conducted, but they have not considered differences in potential scenarios for ASFV contamination between various types of feed ingredient supply chains. Therefore, the purpose of this review is to provide a more holistic understanding of the relative potential risks of ASFV contamination in various global feed ingredient supply chains and provide recommendations for addressing the challenges identified.

Circular Cities: What Are the Benefits of Circular Development?

If cities could become regenerative and adaptive urban ecosystems, in which resource loops were closed and waste was obsolete, their ecological footprint would diminish. In addition, urban resource security would increase, the health of urban populations would improve and urban greenhouse gas emissions would be reduced. These are the principle goals under-pinning the circular city. Circular cities emerge through the process of circular development. Circular development alters cities’ systems of provision to enable circular practices of inhabitants to develop. This manifests as circular food systems and construction, water and nutrient recycling; adaptive reuse of spaces and pop-up activities; bioremediation of contaminated sites and integration of blue-green infrastructure throughout cities. To transform our cities will require significant investment, political support and public engagement. If the benefits of adopting such an approach can be identified, this will begin to make the case for support. The research presented in this paper draws on an inductive and deductive content analysis of relevant literature and interviews with those implementing circular projects in European cities (London, Paris, Amsterdam and Stockholm). It provides a clear definition of the normative concept of circular development. It creates a framework of benefits which are likely to accrue from adopting this approach. It points to the synergistic benefits emerging from circular development. It also highlights problems around valuation of those benefits, the unintended consequences of circular development and the inequalities in accessing benefits across society.

Methane and nitrous oxide emissions from shallow windrow piles for biostabilisation of municipal solid waste

Shallow windrow piles were applied as a low-cost option for biostabilisation of municipal solid wastes (MSW) prior to their utilization as refuse-derived fuel (RDF). A considerable amount of greenhouse gas (GHG) emissions can be emitted during the biostabilisation of MSW, especially when in operation under high moisture conditions such as there are in tropical Asia. This study investigated the emission of methane (CH₄) and nitrous oxide (N₂O) from shallow windrow piles - with heights of 0.5-1.0 m - for the stabilization of MSW at a full-scale facility in Thailand. Measurements of CH₄, CO₂, and N₂O emissions using the static-chamber method revealed high spatial heterogeneity characteristics in all zones with different waste ages. Peak methane emissions were observed after four months of biostabilisation. The average spatial methane emissions from the waste piles ranged from 7.33 to 26.88 g m^-2 d^-1 (14.86 g m^-2 d^-1, on average). The CH₄ generation-rate constant was within the range of 3.3 to 4.0 yr^-1, which is higher than that reported - about 2.20-3.50 yr^-1 - from a deep windrow pile (3.5-4.0 m height). The spatial distribution of N₂O emissions was in the range of 4.51-199.14 mg N₂O t^-1dry wt.d^-1 (6.6-111.7 mg N₂O m^-2 d^-1), similar to those previously studied from landfill operations. This shallow windrow pile technique can be applied as low-cost technology for biostabilisation of MSW in developing countries, where land area is available.Implications: Shallow windrow pile was applied as a low-cost option for biological treatment of municipal solid waste in developing countries where land area is available. This study evaluated the greenhouse gas emission characteristics during the operation of windrow pile. The findings suggest that the emission rates were varied spatially with waste ages in different zones. Higher methane generation rate constant was derived from shallow window pile as compared to deep windrow pile. The methane and nitrous oxide emission factors were derived.

Assessing the eco-effectiveness of a solid waste management plan using agent-based modelling

Municipal Solid Waste Management is yet to be eco-effectively performed, especially in developing countries. In Brazil, a considerable fraction of waste has been improperly landfilled, generating environmental, social and economic problems. In 2018, the government of the state of Paraná released a revised version of its waste management plan, defining improvement strategies to be gradually implemented until 2038. However, these strategies' eco-effectiveness has not been forecasted, nor the plan was deployed to the regional level. This research aims to fill this gap, downscaling the plan to the region of Norte Pioneiro, simulating its implementation and monitoring environmental and economic benefits. The dynamics of waste generation, collection and disposal are investigated using an agent-based model, considering the four population growth scenarios addressed in the plan. Targets for strategies of waste reduction, collection, source-separation and charging of waste fees are modelled. Multiple simulation runs were performed and outputs assessed and discussed. Results show that, if the plan is thoroughly implemented since 2020, at least 650 kilotons of avoided CO_2eq emissions and US$ 40 million in avoided expenditures can be achieved in the most conservative scenario by 2038. Implications from the strategies proposed in the plan are highlighted, and recommendations to improve the plan's eco-effectiveness are outlined.

Reforming MSWM in Sukunan (Yogjakarta, Indonesia): A case-study of applying a zero-waste approach based on circular economy paradigm

Over the past years, Indonesia, the world's fourth most populous country, has confronted environmental problems due to uncontrolled generation of municipal solid waste (MSW). While the integrated solid waste management (ISWM) represents a critical strategy for Indonesia to control its production, it is also recognized that economic approaches also need to be promoted to address the waste problem concertedly. In this case study, empirical approaches are developed to understand how a volume-based waste fee could be incorporated into MSW collection services and how to apply a zero-waste approach in Indonesia by adapting resource recovery initiatives, adapted from Germany's mature experiences in integrating the CE paradigm into the latter's MSWM practices. Currently, Sukunan village (Yogyakarta, Indonesia) promotes waste reduction at sources in the framework of community-based solid waste management (CBSWM) by mobilizing the local community for waste separation (organic and non-organic) and waste recycling. As a result, about 0.2 million Mt of CO_2-eq emissions was avoided annually from local landfills. The economic benefits of recycling activities by the village's community also resulted in 30% reduction of the waste generated. This CBSWM scheme not only saves the government budget on waste collection, transport and disposal, but also extends the lifetime of local landfills as the final disposal sites. By integrating the CE paradigm into its MSWM practices through the implementation of economic instruments and adherence to the rule of law in the same way as Germany does, Indonesia could make positive changes to its environmental policy and regulation of MSW. A sound MSWM in Indonesia could play important roles in promoting the effectiveness of urban development with resource recovery approaches to facilitate its transition towards a CE nationwide in the long-term.

Co-Composting of Khat-Derived Biochar with Municipal Solid Waste: A Sustainable Practice of Waste Management

Biochar is a way to improve the performance of the composting process and the quality of compost. This study was aimed to investigate the optimum ratio of khat straw (Catha edulis) biochar and organic municipal solid waste mixtures to improve the quality of the resulting co-composts. Khat-derived biochar during pyrolysis at 350 °C was added to organic municipal solid waste mix and four co-composting treatments were prepared with the compositions (% w/w): control compost (no biochar) and 5%, 15%, and 25% co-composted biochar in three replicates. The total organic carbon, organic matter, total nitrogen, available phosphorus, and potassium values ranged as 16.76–21.45%, 30.77–40.26%, 0.97–1.68%, 0.58–0.76%, and 12.72–15.29%, respectively. The results confirmed that 5% and 15% co-composted khat biochars had significantly reduced (p < 0.05) organic matter loss and increased the contents of cation exchange capacity, pH, phosphorous, potassium, calcium, magnesium, and zinc compared to the control compost, while some heavy metals (Fe, Cu, and Mn) and EC values in co-composted biochars are lower than the control compost. Khat-derived biochar could be added to municipal organic waste mix at 5–15% (w/w) in order to get better quality of compost, which can be used as biofertilizer.

Alternative strategies towards a sustainable municipal solid waste management system: A case study in Cairo

Major cities in transitional and developing countries are facing the ever-growing challenge of managing solid waste in a sustainable manner. While a variety of treatments exist for solid waste, cities are in need of a sustainable integrated municipal solid waste management (MSWM) system. Such a system is meant to assist them in selecting and investing in an appropriate combination of treatments for the waste they generate, depending on the composition and quantity of this waste. This study presents a systems analysis of the MSWM in Cairo. A constrained non-linear mathematical model is developed to represent an underlying model of a MSWM system, with six waste material flows (cardboard and paper, plastics, metals, glass, organic material, and others). The developed model depicts combinations of five treatment alternatives (composting, anaerobic digestion, mechanical biological treatment, incineration, and landfilling). The treatment methods and their capacity are determined by the model, indicating possible optimal design solutions and recommendations. Starting with an evaluation of the status quo of the MSWM system in Cairo, the paper proposes a staged strategy, involving investigating improvements to the current mixed-waste management system, then exploring the possibility of introducing at-source waste sorting. The environmental and economic implications of different scenarios are analyzed and compared. A material flow analysis, including input data uncertainties, is also conducted by applying substance flow analysis. This analysis shows the difference between the status quo and the proposed improved solutions for diverting waste from landfills and, thus, decreasing carbon dioxide emissions.

“What a Waste”—Can We Improve Sustainability of Food Animal Production Systems by Recycling Food Waste Streams into Animal Feed in an Era of Health, Climate, and Economic Crises?

Food waste has been a major barrier to achieving global food security and environmental sustainability for many decades. Unfortunately, food waste has become an even bigger problem in many countries because of supply chain disruptions during the COVID-19 pandemic and African Swine Fever epidemic. Although Japan and South Korea have been leaders in recycling food waste into animal feed, countries that produce much greater amounts of food waste, such as the United States and the European Union, have lagged far behind. Concerns about the risk of transmission of bacteria, prions, parasites, and viruses have been the main obstacles limiting the recycling of food waste streams containing animal-derived tissues into animal feed and have led to government regulations restricting this practice in the U.S. and EU. However, adequate thermal processing is effective for inactivating all biological agents of concern, perhaps except for prions from infected ruminant tissues. The tremendous opportunity for nitrogen and phosphorus resource recovery along with several other environmental benefits from recycling food waste streams and rendered animal by-products into animal feed have not been fully appreciated for their substantial contribution toward solving our climate crisis. It is time to revisit our global approach to improving economic and environmental sustainability by more efficiently utilizing the abundant supply of food waste and animal tissues to a greater extent in animal feed while protecting human and animal health in food animal production systems.

Food waste-based pellets for feeding grass carp (Ctenopharyngodon idellus): Adding baker's yeast and enzymes to enhance growth and immunity

Protein rich food waste could be used as raw materials for making fish feed pellets, which would diminish the volume of dumped waste into landfills. This study investigated the use of food waste (FW) based pellets composing of 75% food wastes derived from plant materials (cereals, fruit and vegetables) supplemented with yeast and the mixture of bromelain and papain to feed grass carp (Ctenopharyngodon idellus). Generally, improved growth performance (in terms of feed conversion ratio, protein efficiency ratio and relative weight gain) was observed in the diet groups supplemented with yeast (Saccharomyces cerevisiae). The most optimal dose was 25 g/kg yeast with enzymes (bromelain and papain, at the ratio of 1:1) and protein utilization was enhanced. Fish immunity was also stimulated, which indicated by the higher nitroblue tetrazolium and bactericidal activities. Moreover, resistance against Aeromonas hydrophilia was enhanced. It is envisaged that food waste could be widely used as feeds for culturing herbivorous fish and adding supplements such as baker's yeast and enzymes will further enhance the feed conversion ratio and fish immunity.

Life cycle assessment of municipal solid waste management options for India

Life Cycle Assessment (LCA) tool can be used for environmental assessment of Municipal Solid Waste Management (MSWM) system. The present study aims to evaluate the impact of MSWM system in Nagpur city, India under four different scenarios. i.e., composting combined with landfilling (S1), material recovery facility (MRF) & composting combined with landfilling (S2), MRF & anaerobic digestion (AD) combined with landfilling (S3) and MRF, AD & composting combined with landfilling (S4) using LCA tool. The sensitivity analysis was also performed for evaluating the influence of recycling rate of valuable resources in all the considered scenarios. The scenarios were compared using Gabi 8.5.0.79 model and CML-1A impact characterization method. S2 was found to have the least environmental impacts on global warming, human toxicity, eutrophication, and photochemical ozone creation potential categories. The sensitivity analysis indicated an inversely proportional relation between change in recycling rate and total environmental burdens.

Learning from integrated management approaches to implement the Nexus

In the 1990s, the emergence of Integrated Management Approaches to water, land and waste established a widely accepted understanding on integration of environmental systems. Nexus Approaches try to often build on these. This paper assesses i) the intended goals and features of three Integrated Management Approaches (Integrated Natural Resources Management - INRM, Integrated Water Resources Management - IWRM and Integrated Solid Waste Management - ISWM) and two Nexus Approaches (Water-Energy-Food (WEF) Nexus and Water-Soil-Waste (WSW) Nexus), and ii) how target systems and their integration are viewed in each of the Integrated Management Approaches. From this we assess commonalities and some lessons-learned for the Nexus. The method is based on a systematic literature review and a document analysis. From 1652 articles 52 peer reviewed papers were analysed. The results show that in terms of goals the Nexus Approaches are very similar to Integrated Management Approaches with the addition of clearly wanting to address governance and policy aspects e.g. in the WEF Nexus. Nexus Approaches try to move away from a single-resource centric view (e.g. WSW Nexus) and intend to go beyond resources towards sectors (e.g. WEF Nexus). It cannot be confirmed, that integration is clearly addressed in the analysed Integrated Management Approaches and what integration means is hardly defined. To provide some clarity for Nexus Approaches we propose a concept to describe integration by using "categories of integration" and the term "aspect" which includes systems, subsystems and other aspects alike.

Improvement of waste management practices in a fast expanding sub-megacity in Pakistan, on the basis of qualitative and quantitative indicators

This paper deals with an analysis of waste management practices in the fast-growing city of Gujranwala with 2.6 million inhabitants, with a fast growing middle income group of 56%, and an urbanization rate of 3.49% per annum. This city is like many other cities in the developing world, characterised by hardly any waste management infrastructure. The study comprises: (1) an inventory of current waste flows, per income group as well as per season, (2) an inventory of waste management shortcomings, (3)) a what-if analysis on the carbon footprint of three waste treatment techniques. The inventory of current waste flows is based on a comprehensive site study involving 776 samples in total. The waste management shortcomings have been qualitatively analysed by Wasteaware model, which deals with physical aspects (public health, environmental control, resource management) as well as governance factors (user & provider inclusivity, financial stability, institutions & policies). The what-if analysis of the carbon footprint has been based on an LCA-based tool. The findings of this study are that: (1) the optimum choice of waste treatment scenario differs for the seasons, (2) the high and middle income groups have nearly half of the share of the waste (3) the Wasteaware system appears to be a powerful tool to communicate the weak spots and to make stakeholders aware of the opportunities for improvement. The novelty of this paper is that it focused on the impact of household income groups in combination with seasonal differences while comparing different waste disposal scenarios.

Circular Cities: Challenges to Implementing Looping Actions

Currently cities consume 60–80% of natural resources globally. They produce 50% of global waste and 75% of green-house gas emissions. The UN estimates that 66% of the world’s population will live in cities by 2050 while the global urban footprint will triple over the years to 2030. Thus cities, as a system of production and consumption, threaten the environmental sustainability of the globe. Looping actions—reuse, recycling and recovery of resources (materials, energy, water, land and infrastructure)—can help to address resource scarcity and wastage in cities. However, there are many challenges to implementation. Much of the literature explores the challenges to looping actions within resource sectors and for specific actions (i.e., challenges to adaptive reuse of buildings, recycling of material waste, energy recovery from sewage). It often does so without any clear reference to context. Nexus solutions are becoming a popular resource looping response to tackling wastage in cities. Some of the challenges to implementation have been explored, but influence of context has not been investigated. In this paper we explore the challenges facing the implementation of looping actions in cities. Using a mixed methods approach, we identify 58 challenges to looping actions across eight themes. We also establish the challenges to implementing a nexus solution. The research identifies five common implementation challenges. Addressing these challenges could enable looping actions across resource types in cities. The research also demonstrates how context affects the challenges to implementing looping actions and nexus solutions in cities. Nevertheless, the analysis suggests that there are some common levers for promoting looping actions and nexus solutions in cities, regardless of context.

Reduction of greenhouse gases (GHGs) and short-lived climate pollutants (SLCPs) from municipal solid waste management (MSWM) in the Philippines: Rapid review and assessment

Municipal solid waste management (MSWM) is considered one of the serious environmental issues in the Philippines, with corresponding linkages to the climate change and Sustainable Development Goals (SDGs). However, methane (CH₄) linked with indiscriminate dumping of municipal solid waste has received the much attention with regard to public health and climate change. The impacts of black carbon (BC) are less documented and understood. This paper aims to review the status of MSWM in the Philippines and makes efforts to assess the scale of short-lived climate pollutants (SLCPs), including both CH₄, and BC, associated with the country's waste sector. Utilising available national level data and following a life-cycle assessment (LCA) approach, the paper offers preliminary projections of SLCP emissions resulting from present MSWM practices. In addition, it examines model mitigation scenarios based on priority actions identified within the country's national policy on waste management, Republic Act 2003 (RA 9003). Data analysis was conducted using an Emission Quantification Tool (EQT) developed by the Institute for Global Environmental Strategies (IGES) through its work under the Climate and Clean Air Coalition (CCAC) - Municipal Solid Waste Initiative (MSWI). Following a summary of key findings, the paper affirms that control of methane from disposal practices and of BC from waste collection and open burning requires urgent attention in the Philippines. Continued awareness raising, institutionalising regulatory policies on SLCPs, and further enhancing data collection and capacity building on waste-related BC emissions remain key priorities for the country.

Intergovernmental panel on climate change's landfill methane protocol: Reviewing 20 years of application

The Intergovernmental Panel on Climate Change (IPCC) protocol for predicting national methane emission inventories from landfills was published 22 years ago in the 1996 Revised Guidelines. There currently exists a broad dataset to review landfill parameters and reported values and their appropriateness in use and application in a range of site-specific, regional, and national estimates. Degradable organic carbon (DOC) content was found to range from 0.0105 to 0.65 g C/g waste, with an average of 0.166 g C/g waste. The fraction of DOC that would anaerobically degrade (DOC _f) was reported to range from 50-83%, whereas higher and lower values have been experimentally determined for a variety of waste components, such as wood (0-50%) and food waste (50-75%). Where field validation occurred for the methane correction factor, values were substantially lower than defaults. The fraction of methane in anaerobic landfill gas ( F) default of 50% is almost universally applied and is appropriate for cellulosic wastes. The methane generation rate constant ( k) varied widely from 0.01 to 0.51 y^-1, representing half-lives from 1 to 69 years. Methane oxidation (OX) default values of 0 and 10% may be valid, but values greater than 30% have been reported for porous covers at managed sites. The IPCC protocol is a practical tool with uncertainties and limitations that must be addressed when used for purposes other than developing inventories.

Municipal solid waste incineration plant: A multi-step approach to the evaluation of an energy-recovery configuration

This study proposes a multi-step approach to evaluating the environmental and economic aspects of a thermal treatment plant with an energy-recovery configuration. In order to validate the proposed approach, the Turin incineration plant was analyzed, and the potential of the incinerator and several different possible connections to the district heating network were then considered. Both local and global environmental balances were defined. The global-scale results provided information on carbon dioxide emissions, while the local-scale results were used as reference values for the implementation of a Gaussian model that could evaluate the actual concentrations of pollutants released into the atmosphere. The economic aspects were then analyzed, and a correspondence between the environmental and economic advantages defined. The results showed a high energy efficiency for the combined production of heat and electricity, and the opportunity to minimize environmental impacts by including cogeneration in a district heating scheme. This scheme showed an environmental advantage, whereas the electricity-only configuration showed an economic advantage. A change in the thermal energy price (specifically, to 40 €/MWh), however, would make it possible to obtain both environmental and economic advantages.

Use of food waste, fish waste and food processing waste for China's aquaculture industry: Needs and challenge

China's aquaculture industry is growing dramatically in recent years and now accounts for 60.5% of global aquaculture production. Fish protein is expected to play an important role in China's food security. Formulated feed has become the main diet of farmed fish. The species farmed have been diversified, and a large amount of 'trash fish' is directly used as feed or is processed into fishmeal for fish feed. The use of locally available food waste as an alternative protein source for producing fish feed has been suggested as a means of tackling the problem of sourcing safe and sustainable feed. This paper reviews the feasibility of using locally available waste materials, including fish waste, okara and food waste. Although the fishmeal derived from fish waste, okara or food waste is less nutritious than fishmeal from whole fish or soybean meal, most fish species farmed in China, such as tilapia and various Chinese carp, grow well on diets with minimal amounts of fishmeal and 40% digestible carbohydrate. It can be concluded that food waste is suitable as a component of the diet of farmed fish. However, it will be necessary to revise regulations on feed and feed ingredients to facilitate the use of food waste in the manufacture of fish feed.

Assessment of carbon footprint emissions and environmental concerns of solid waste treatment and disposal techniques; case study of Malaysia

Malaysian authorities has planned to minimize and stop when applicable unsanitary dumping of waste as it puts human health and the environment at elevated risk. Cost, energy and revenue are mostly adopted to draw the blueprint of upgrading municipal solid waste management system, while the carbon footprint emissions criterion rarely acts asa crucial factor. This study aims to alert Malaysian stakeholders on the uneven danger of carbon footprint emissions of waste technologies. Hence, three scenarios have been proposed and assessed mainly on the carbon footprint emissions using the 2006 IPCC methodology. The first scenario is waste dumping in sanitary landfills equipped with gas recovery system, while the second scenario includes anaerobic digestion of organics and recycling of recyclable wastes such as plastic, glass and textile wastes. The third scenario is waste incineration. Besides the carbon footprint emissions criterion, other environmental concerns were also examined. The results showed that the second scenario recorded the lowest carbon footprint emissions of 0.251t CO₂ eq./t MSW while the third scenario had the highest emissions of 0.646t CO₂ eq./t MSW. Additionally, the integration between anaerobic digestion and recycling techniques caused the highest avoided CO₂ eq. emissions of 0.74t CO₂ eq./t MSW. The net CO₂ eq. emissions of the second scenario equaled -0.489t CO₂ eq./t MSW due to energy recovery from the biogas and because of recycled plastic, glass and textile wastes that could replace usage of raw material. The outcomes also showed that the first scenario generates huge amount of leachate and hazardous air constituents. The study estimated that a ton of dumped waste inside the landfills generates approximately 0.88m³ of trace risky compounds and 0.188m³ of leachate. As for energy production, the results showed that the third scenario is capable of generating 639kWh/t MSW followed by the second scenario with 387.59kWh/t MSW. The first scenario produced 296.79kWh/t MSW. In conclusion, the outcomes of this study recommend an integrated scenario of anaerobic digestion and recycling techniques to be employed in Malaysia.

The impacts of decision uncertainty on municipal solid waste management

Municipal solid waste treatment options are not necessarily pragmatic if the stakeholders in the system don't mutually agree on their shares of liabilities. Stakeholders will select an option if their benefits are maximized and costs are minimized. A decision support framework is required to assess various waste treatment options and predict the optimal decision, considering multiple criteria and conflicting preferences of multiple stakeholders. Because of the inherent complexity, uncertainty is unavoidable and should be acknowledged to enhance the reliability in the decision-making process. Uncertainties in the cost and benefit estimates, and stakeholders' ability in verbalizing their preferences and their knowledge about each other's priorities can impact the outcome of such environmental management problem. In this study, uncertainty assessment methods such as sensitivity analysis, fuzzy Analytical Hierarchy Process, and Bayesian games have been explored. A case study in Vancouver (BC, Canada) has been used as a proof of concept.

Carbon footprint and energy use of food waste management options for fresh fruit and vegetables from supermarkets

Food waste is a problem with economic, environmental and social implications, making it both important and complex. Previous studies have addressed food waste management options at the less prioritised end of the waste hierarchy, but information on more prioritised levels is also needed when selecting the best available waste management options. Investigating the global warming potential and primary energy use of different waste management options offers a limited perspective, but is still important for validating impacts from the waste hierarchy in a local context. This study compared the effect on greenhouse gas emissions and primary energy use of different food waste management scenarios in the city of Växjö, Sweden. A life cycle assessment was performed for four waste management scenarios (incineration, anaerobic digestion, conversion and donation), using five food products (bananas, tomatoes, apples, oranges and sweet peppers) from the fresh fruit and vegetables department in two supermarkets as examples when treated as individual waste streams. For all five waste streams, the established waste hierarchy was a useful tool for prioritising the various options, since the re-use options (conversion and donation) reduced the greenhouse gas emissions and the primary energy use to a significantly higher degree than the energy recovery options (incineration and anaerobic digestion). The substitution of other products and services had a major impact on the results in all scenarios. Re-use scenarios where food was replaced therefore had much higher potential to reduce environmental impact than the energy recovery scenarios where fossil fuel was replaced. This is due to the high level of resources needed to produce food compared with production of fossil fuels, but also to fresh fruit and vegetables having a high water content, making them inefficient as energy carriers. Waste valorisation measures should therefore focus on directing each type of food to the waste management system that can substitute the most resource-demanding products or services, even when the whole waste flow cannot be treated with the same method.

Urban governance and the systems approaches to health-environment co-benefits in cities

The term "co-benefits" refers to positive outcomes accruing from a policy beyond the intended outcome, often or usually in other sectors. In the urban context, policies implemented in particular sectors (such as transport, energy or waste) often generate multiple co-benefits in other areas. Such benefits may be related to the reduction of local or global environmental impacts and also extend into the area of public health. A key to identifying and realising co-benefits is the adoption of systems approaches to understand inter-sectoral linkages and, in particular, the translation of this understanding to improved sector-specific and city governance. This paper reviews a range of policies which can yield health and climate co-benefits across different urban sectors and illustrates, through a series of cases, how taking a systems approach can lead to innovations in urban governance which aid the development of healthy and sustainable cities.

Reducing the land use of EU pork production: where there's swill, there's a way

Livestock production occupies approximately 75% of agricultural land, consumes 35% of the world's grain, and produces 14.5% of anthropogenic greenhouse gas emissions. With demand for meat and dairy products forecast to increase 60% by 2050, there is a pressing need to reduce the footprint of livestock farming. Food wastes have a long history as a source of environmentally benign animal feed, but their inclusion in feed is currently banned in the EU because of disease control concerns. A number of East Asian states have in the last 20 years, however, introduced regulated, centralised systems for safely recycling food wastes into animal feed. This study quantifies the land use savings that could be realised by changing EU legislation to promote the use of food wastes as animal feed and reviews the policy, public, and industry barriers to the use of food waste as feed. Our results suggest that the application of existing technologies could reduce the land use of EU pork (20% of world production) by one fifth, potentially saving 1.8 million hectares of agricultural land. While swill presents a low-cost, low-impact animal feed, widespread adoption would require efforts to address consumer and farmer concerns over food safety and disease control.

Development of performance indicators for municipal solid waste management (PIMS): A review

The aim of this paper is to review papers on municipal solid waste management (SWM) systems, especially on performance indicators (PIs), and suggest practical methods to manage the same by administrators. Worldwide, about 4 billion metric tons of solid waste (SW) is generated annually; the management of SW across cities is increasingly getting more complex and the funds available for providing service to citizens are shrinking. Analysis of the non-technical research papers shows that focus areas on SW can be grouped into 18 types, one being PIs. Historically, PIs for municipal SWM (PIMS) commenced with the publication of guidelines by various government agencies, starting in 1969. This was followed by a few benchmarking studies, commencing in 1998, by various international institutions. Many published comparative studies also disseminated good practices across the cities. From the 1990s onwards, research work started defining PIMS. These initiatives by various researchers took multiple dimensions and are reviewed in this paper. In almost all studies, the PIMS is measured in terms of investment decisions, public acceptance levels, social participation and environmental needs. The multiple indicators are complex, however, and managers of cities need simple tools to use. To make it simple, five-factor PIs are arrived at, considering simplicity and covering all the factors. A research agenda is outlined for future directions in the areas of cost reduction, citizens' services, citizen involvement and environmental impact.

Polyethylene recycling: Waste policy scenario analysis for the EU-27

This paper quantifies the main impacts that the adoption of the best recycling practices together with a reduction in the consumption of single-use plastic bags and the adoption of a kerbside collection system could have on the 27 Member States of the EU. The main consequences in terms of employment, waste management costs, emissions and energy use have been quantified for two scenarios of polyethylene (PE) waste production and recycling. That is to say, a "business as usual scenario", where the 2012 performances of PE waste production and recycling are extrapolated to 2020, is compared to a "best practice scenario", where the best available recycling practices are modelled together with the possible adoption of the amended Packaging and Packaging Waste Directive related to the consumption of single-use plastic bags and the implementation of a kerbside collection system. The main results show that socio-economic and environmental benefits can be generated across the EU by the implementation of the best practice scenario. In particular, estimations show a possible reduction of 4.4 million tonnes of non-recycled PE waste, together with a reduction of around €90 million in waste management costs in 2020 for the best practice scenario versus the business as usual scenario. An additional 35,622 jobs are also expected to be created. In environmental terms, the quantity of CO2 equivalent emissions could be reduced by around 1.46 million tonnes and the net energy requirements are expected to increase by 16.5 million GJ as a consequence of the reduction in the energy produced from waste. The main analysis provided in this paper, together with the data and the model presented, can be useful to identify the possible costs and benefits that the implementation of PE waste policies and Directives could generate for the EU.

Methodology to design a municipal solid waste generation and composition map: a case study

The municipal solid waste (MSW) management is an important task that local governments as well as private companies must take into account to protect human health, the environment and to preserve natural resources. To design an adequate MSW management plan the first step consists in defining the waste generation and composition patterns of the town. As these patterns depend on several socio-economic factors it is advisable to organize them previously. Moreover, the waste generation and composition patterns may vary around the town and over the time. Generally, the data are not homogeneous around the city as the number of inhabitants is not constant nor it is the economic activity. Therefore, if all the information is showed in thematic maps, the final waste management decisions can be made more efficiently. The main aim of this paper is to present a structured methodology that allows local authorities or private companies who deal with MSW to design its own MSW management plan depending on the available data. According to these data, this paper proposes two ways of action: a direct way when detailed data are available and an indirect way when there is a lack of data and it is necessary to take into account bibliographic data. In any case, the amount of information needed is considerable. This paper combines the planning methodology with the Geographic Information Systems to present the final results in thematic maps that make easier to interpret them. The proposed methodology is a previous useful tool to organize the MSW collection routes including the selective collection. To verify the methodology it has been successfully applied to a Spanish town.

Mass, energy and material balances of SRF production process. Part 1: SRF produced from commercial and industrial waste

This paper presents the mass, energy and material balances of a solid recovered fuel (SRF) production process. The SRF is produced from commercial and industrial waste (C&IW) through mechanical treatment (MT). In this work various streams of material produced in SRF production process are analyzed for their proximate and ultimate analysis. Based on this analysis and composition of process streams their mass, energy and material balances are established for SRF production process. Here mass balance describes the overall mass flow of input waste material in the various output streams, whereas material balance describes the mass flow of components of input waste stream (such as paper and cardboard, wood, plastic (soft), plastic (hard), textile and rubber) in the various output streams of SRF production process. A commercial scale experimental campaign was conducted on an MT waste sorting plant to produce SRF from C&IW. All the process streams (input and output) produced in this MT plant were sampled and treated according to the CEN standard methods for SRF: EN 15442 and EN 15443. The results from the mass balance of SRF production process showed that of the total input C&IW material to MT waste sorting plant, 62% was recovered in the form of SRF, 4% as ferrous metal, 1% as non-ferrous metal and 21% was sorted out as reject material, 11.6% as fine fraction, and 0.4% as heavy fraction. The energy flow balance in various process streams of this SRF production process showed that of the total input energy content of C&IW to MT plant, 75% energy was recovered in the form of SRF, 20% belonged to the reject material stream and rest 5% belonged with the streams of fine fraction and heavy fraction. In the material balances, mass fractions of plastic (soft), plastic (hard), paper and cardboard and wood recovered in the SRF stream were 88%, 70%, 72% and 60% respectively of their input masses to MT plant. A high mass fraction of plastic (PVC), rubber material and non-combustibles (such as stone/rock and glass particles), was found in the reject material stream.