Search Results (48)

Municipal waste composition is commonly measured at a single point, even though recovery, mixing and handling can alter the stream before disposal. This study examined municipal solid waste in Sialkot, Pakistan, during an eight-day campaign from 27 December 2021 to 3 January 2022. A total of 672 physical-characterization samples was obtained from residential, commercial, institutional, industrial and street-sweeping sources. Household generation was 0.42, 0.46 and 0.51 kg per person per day in low-, middle- and high-income proxy areas, respectively. Kitchen waste declined from 45.91% at the source to 34.20% at communal storage and 23.45% at the dumpsite. Recyclable paper and plastic also declined, whereas dust and fines increased from 2.05% at the source to 19.60% at storage and 21.78% at disposal. Six mixed-waste composites showed moisture contents of 30.72–53.06%, ash contents of 15.85–45.04% and gross calorific values of 2924–12,530 kcal kg⁻¹. The results demonstrate that monitoring location materially affects estimated recycling and treatment potential. A multi-point monitoring protocol is therefore recommended for cities with mixed collection and informal material recovery. Full article

The article assesses the energy potential of biodegradable municipal waste in the Krakow Metropolitan Area, analyzing the feasibility of using derived biomethane for residential heating by 2050. Framed within the circular economy and the European Green Deal, the study highlights a significant technological gap in Poland, contrasting it with successful models in Austria, Germany, and Italy. Empirical data from 2023–2024 indicate that kitchen waste (code 20 01 08) is an optimal feedstock for methane fermentation due to its stable annual flow, whereas green waste (code 20 02 01) presents challenges due to high seasonality. Simulation modeling suggests that annual biomethane production from kitchen waste could range from approximately 1.23 million m³ (Variant 3) to over 1.42 million m³ (Variant 4). A key finding is the synergy between waste-to-energy transformation and building thermal modernization. By reducing energy demand, the consistent volume of kitchen waste processed from 2024 could potentially supply heating for between 4928 and 8180 apartments by 2050. Ultimately, the research underscores the role of metropolitan integration in achieving sustainable development goals, enhancing regional energy security, and reducing emissions. Full article

Peri-urban regions around Southeast Asian megacities connect agriculture, markets, food-service facilities, households, and municipal waste systems, yet comparable data for individual waste streams are often unavailable. This study presents a screening framework for selecting the first organic waste streams and node types to measure in Tangerang Raya, Indonesia, before treatment performance data are available. The framework complements, rather than replaces, city scale circularity monitoring, life cycle assessment, and technology selection tools. Public and institutional data were screened by evidence class and temporal and spatial compatibility. The core Peri-Urban Organic Waste Circularity Readiness Index (PU-OCRI) evaluates five intrinsic criteria: feedstock concentration, source separation readiness, treatment pre-screening compatibility, institutional readiness, and the safety/quality gate. Scores represent collective author judgments linked to a criterion level evidence trail; they have not been independently rated by local stakeholders or empirically calibrated. Korea linked support is assessed separately and cannot affect the index. Available evidence included 3248.1 t of large chili production in Kabupaten Tangerang in 2024, 798,406 t yr⁻¹ of reported potential municipal-waste generation in Kota Tangerang in 2024, and a planning-based estimate that 52.89% of non-residential waste in Kota Tangerang Selatan was biogenic organic material. Under equal weights, market-linked organics scored 76/100 and garden and landscape organics 72; production-side residues and household food waste each scored 56, and mixed residual waste scored 32. In 100,000 weight only simulations, market linked organics ranked first in 65.9% of runs and garden and landscape organics in 31.2%. When each score was allowed to vary by one point and sampled together with the weights, the corresponding first-rank frequencies were 50.7% and 40.7%. These results define a provisional paired audit hypothesis, not evidence of superior circular-economy performance. A required 8–12-week comparison of market/food-service and garden/landscape nodes will apply predefined criteria for mass stability, contamination, safety, treatment feasibility, cost, and operator and stakeholder participation before scores are updated or any treatment or scale-up decision is made. Korea-linked cooperation is limited to digital logging, training, QA/QC, and pilot-operation protocols. Data provenance is explicit: the 798,406 t yr⁻¹ value is the issuing agency’s population × per-capita estimate, whereas 52.89% is an author calculated category sum (kitchen + garden + wood) used only as a screening proxy, not as a direct stream level measurement or the plan’s official aggregate organic fraction. Full article

Approximately 30% of the food produced worldwide is wasted, and a substantial share of municipal food waste still contains non-biodegradable packaging material after sorting. This study investigated an aerobic biodrying process for reducing the moisture content of mixed food-waste fractions, containing varying proportions of green biomass, vegetables, kitchen waste, and packaging-derived plastics, in order to increase their calorific value and obtain a refuse-derived fuel (RDF). Four substrate variants (K1–K4, including a control without added plastics) were biodried in laboratory-scale bioreactors. Process temperatures exceeded 70 °C in all variants, and the addition of plastics increased both the cumulative and the average temperature relative to the control. The plastic fraction recovered after biodrying showed the largest increase in calorific value, reaching over 15 MJ∙kg⁻¹, while the AT4 respiration activity of the separated compost fraction decreased to around 10 mg O₂ g⁻¹ DM in all variants, indicating good storage stability. The results suggest that pre-treated plastics did not adversely affect the biodrying process and, owing to their structuring properties, may support biological decomposition of the remaining biomass; these preliminary, single-run findings should be confirmed in replicated trials. Full article

This study investigates whether the optimal utilization of the biomass potential contained in municipal solid waste (MSW) can support the implementation of circular economy (CE) principles and contribute to climate policy objectives, particularly the reduction in greenhouse gas (GHG) emissions in the waste management sector. The analysis evaluates whether waste-to-energy recovery can support the objectives of the European Green Deal, including a 55% reduction in GHG emissions by 2035 and the achievement of climate neutrality by 2050. The assessment was conducted for two MSW streams generated in a Polish municipality: separately collected biowaste and residual MSW remaining after meeting European reuse and recycling targets. The study summarizes the results of detailed experimental investigations of the physicochemical and fuel properties of these waste streams. Proven and commercially available energy recovery technologies, including anaerobic digestion (AD) of biowaste and incineration of residual waste, were analyzed. GHG emissions were assessed using a life cycle assessment (LCA) approach, taking into account both direct emissions and avoided emissions resulting from the substitution of conventional energy and fertilizer production. The experimental results revealed significant variability in the biodegradability and energy potential of individual biowaste fractions, with the highest biogas yields observed for kitchen waste. Residual waste exhibited a considerable calorific value and a significant share of renewable energy due to its biomass content. The results indicate that the share of renewable energy in electricity generated from waste is expected to increase from 46.1% in 2025 to 49.9% in 2040. In relation to the total electricity demand of the analyzed city, energy recovered from waste accounts for 1.8 ± 0.3% in 2025 and 1.3 ± 0.2% in 2040. Scenario-based modeling demonstrated that the target system, maximizing energy recovery from both biowaste and residual waste, achieves a consistently negative GHG emission balance throughout the analyzed period (2025–2040), ranging from −72 ± 15 kg CO₂-eq/ton in 2025, through the most favorable value of −81 ± 17 kg CO₂-eq/ton in 2035, to −57 ± 12 kg CO₂-eq/ton in 2040, expressed per ton of total managed biowaste and residual waste. Full article

Co-combustion in a refuse incinerator is a primary method for treating aged refuse (AR). Given the high contents of heavy metals and chlorine in AR, it is crucial to investigate their release and fate during co-combustion to achieve environmentally sound treatment. This study investigated the release and volatilization of heavy metals (Cd, Cr, Zn, Ni, Cu, Pb) and HCl during the co-combustion of AR and municipal solid waste (MSW) through chemical thermodynamic equilibrium analysis. The effects of several parameters on the volatilization of heavy metals and HCl were analyzed, including incineration temperature, the N₂/O₂ ratio, the degree of refuse classification, the blending ratio of AR, and the effects of conventional calcium-based additives. The results showed that high temperature promoted the volatilization of Cd, Pb, Cu, Ni, and HCl. A lower N₂/O₂ ratio suppressed Zn and HCl volatilization. A higher degree of MSW classification (with lower proportions of kitchen and wood waste) and an increased AR blending ratio enhanced Zn fixation. CaO at high temperature only suppressed HCl volatilization, with a minor effect on heavy metals. Two modified calcium-based additives (CaBSiO₄OH and CaB₅SiO₉(OH)₅) with strong high-temperature Cu removal capabilities were explored, and their risk index was analyzed. Full article

Background: Environmental surfaces are key reservoirs for pathogen transmission, with the survival of bacteria on fomites influenced by factors such as temperature, humidity, and microbial interactions. This study aimed to determine microbial surface contamination and to determine the antimicrobial resistance profile of bacteria isolated from the indoor surface where the presence of cockroaches was observed in households of the Greater Letaba Municipality (GLM), South Africa. Methods: Swab samples were collected from kitchen countertops and food storage areas with visible cockroach activity. Bacteria were isolated and identified using standard microbiological methods, and antimicrobial susceptibility testing (AST) was conducted with the Vitek^® Automated 2 system. Results: Of the 120 samples collected, 82 (68%) showed bacterial growth, resulting in 190 isolates. The majority of isolates (93%) were Gram-negative, comprising Klebsiella, Pseudomonas, Enterobacter, Escherichia, Serratia, Stenotrophomonas, Pantoea, Raoultella, and Salmonella species, with 98% demonstrating multidrug resistance (MDR) to multiple antibiotics. Resistance was particularly high against gentamicin (94%), fluoroquinolones (88%) and amikacin (77%). Among Gram-positive isolates, all belonged to the Enterococcus species, with 22% being resistant to one or two of the tested antimicrobial agents and 78% exhibiting MDR. Conclusions: The study revealed a high prevalence of antibiotic resistance in both Gram-positive and Gram-negative bacteria isolated from household surfaces. The spread of antibiotic-resistant pathogens via environmental surfaces presents a significant risk to human health, safety, and well-being. Full article

Kitchen waste management strongly affects greenhouse gas (GHG) emissions, especially in small municipalities with limited treatment options. This study assessed alternative strategies for Aya Town, Japan, by integrating life cycle assessment (LCA) with Geographical Information System (GIS)-based transport analysis. Six scenarios were designed, ranging from mandatory composting with frequent collection to full incineration at a regional waste-to-energy (WtE) facility. Emissions were estimated from transport, composting, and incineration processes, with sensitivity tests on composting electricity use (20, 50, and 90 kWh per ton) and WtE efficiency (15%, 17.9%, 20%, and 25%). The results showed that reducing collection frequency lowered emissions by about 9% relative to the current system, while decreasing composting participation further reduced emissions. Full incineration yielded the lowest emissions, whereas sensitivity analyses confirmed that facility parameters influenced absolute values but not the relative ranking of scenarios. These findings emphasize the importance of transport logistics, participation rates, and infrastructural context. High-quality compost may justify limited voluntary composting; however, WtE incineration remains the most robust option for climate mitigation in Japan’s incineration-based waste management system. Full article

Municipal solid waste (MSW) management is identified as a significant sustainability concern. Source segregation (SS) is the most effective method of managing MSW, and anaerobic digestion (AD) is the most efficient treatment method. The aim of this study was to analyze the impact of waste collection rules on the efficiency and performance of AD. The potential biomethane yields for SS-kitchen waste and SS-biowaste were calculated, determined in laboratory tests, and verified full-scale. The content of the organic fraction in SS-biowaste reached about 81 to 86%; however, regarding SS-kitchen waste, it reached almost 92%. The primary contaminants were plastics. The obtained biogas yield was slightly higher for SS-kitchen waste (136.2 m³/ton), compared to SS-biowaste (116.6 m³/ton). The pH values, acidity, and alkalinity indicated no risk of exploitation using both feedstocks. However, in the case of SS-kitchen waste, the acetic acid content was about 2.5 times higher than that of SS-biowaste. Furthermore, the acetic acid was noted in the outlet section (about 140–160 mg/kg), indicating no complete organic matter decomposition. Regarding SS-kitchen waste, the calculated methane yield reached 137.1 m³_CH4/ton and laboratory tests showed a methanogenic potential of 129.7 m³_CH4/ton, while at full-scale, it reached about 82.2 m³_CH4/ton. The research confirmed that the SS of biowaste positively impacts MSW management by improving waste composition and increasing recycling possibilities. AD is an effective biowaste treatment process, allowing energy recovery from waste. Full article

Given the increasing volume of selectively collected bio-waste and the requirement to increase waste treatment system energy efficiency, dry anaerobic digestion (DAD) represents a more sustainable choice for the treatment of municipal organic fraction instead of conventional technologies. The current paper provides an overview of the existing knowledge on DAD of green waste or kitchen waste collected selectively. Key substrates characteristics (chemical composition, methane potential), novel reactor design and process conditions relevant to effective digestion at elevated dry matter content are considered. Of special interest is the process intensification techniques, impact of contamination and co-fermentation opportunity with other biodegradable wastes. This article also discusses energy and economic performance of DAD plants and puts their environmental burden in perspective versus other bio-waste treatment processes. The current legislation and DAD’s role in the circular economy are also considered. Selectively collected biowaste has significant energy potential and dry anaerobic digestion is an effective technology, especially in areas with limited water availability, offering both waste volume reduction and minimized energy losses. The aim of this work is to introduce the potential of this technology as a sustainable option within the context of renewable energy and modern waste management. Full article

Determining the amount of biowaste generated, separated, and recycled at source in households (BHrecycled) is crucial for assessing its potential inclusion in the total mass of waste prepared for reuse and recycling on the country level. Although the EU has introduced standardized rules for BHrecycled measurement, it is still a major challenge. This study, the first to be conducted on a large scale in Poland and the EU countries, aimed to determine the actual mass of BHrecycled (kitchen waste (B_K) per capita per year (kg/(capita·year)) and garden waste (B_G) per square meter of green area (kg/(m²·year)) in 1150 households that use an active composting unit located in more than 400 municipalities in all the voivodeships in Poland. Each municipality is characterized by individual MSW generation (MSW_G) values (the amount of waste generated per capita per year). The MSW_G values of the municipality where the household was located were used to group the data of B_K and B_G. In Poland, the average masses of B_K and B_G remained within the ranges of 81.02–107.49 kg/(capita·year) and 1.02–2.87 kg/(m²·year), respectively, across the MSW_G value. However, there was no clear statistical relationship between the MSW_G value and B_K or B_G. The average masses of B_K and B_G were ca. 97 kg/(capita·year) and ca. 2 kg/(m²·year). These results enable the determination of the total amount of BHrecycled in Poland. By incorporating these findings into waste management, strategies, monitoring, and reporting practices can be improved. Moreover, it promotes compliance with the EU recycling targets. Full article

The amount of waste generated by society is constantly increasing. Consequently, there is a need to develop new and better methods of treating it. A significant part of municipal waste is biowaste, which can be treated as a source of valuable resources such as nutrients, organic matter, and energy. The present work aims to determine the properties of the tested household biowaste and the possibility of using it as feedstock in slow pyrolysis to obtain biochar. The slow pyrolysis process of the biowaste was carried out in an electrically heated Horizontal Tube Furnace (HTF) at temperatures of 400 °C, 500 °C, and 600 °C in a nitrogen atmosphere. The analysis showed that depending on the type and composition of the biowaste, its properties are different. All the biowaste tested has a high moisture content (between 63.51% and 81.53%), which means that the biowaste needs to be dried before the slow pyrolysis process. The characteristics of kitchen biowaste are similar to those of food waste studied by other researchers in different regions of the world. In addition, the properties of kitchen biowaste are similar to those of the typical biomasses used to produce biochar via slow pyrolysis, such as wood, almond shells, and rice husks. Both kinds of garden biowaste tested may have been contaminated (soil, rocks) during collection, which affected the high ash content of spring (17.75%) and autumn (43.83%) biowaste. This, in turn, affected all the properties of the garden biowaste, which differed significantly from both the literature data of other garden wastes and from the properties of typical biomass feedstocks used to produce biochar in slow pyrolysis. For all biowaste tested, it was shown that as the pyrolysis temperature increases, the yield of biochar decreases. The maximum mass yield of biochar for kitchen, spring garden, and autumn garden biowaste was 36.64%, 66.53%, and 66.99%, respectively. Comparing the characteristics of biowaste before slow pyrolysis, biochar obtained from kitchen biowaste had a high carbon content, fixed carbon, and a higher HHV. In contrast, biochar obtained from garden biowaste had a lower carbon content and a lower HHV. Full article

The aim of this study is to determine the effect of the separation of solid waste at the source on three different sustainable solid waste management scenarios using the analytic hierarchy process. In this context, the type of source separation method that would be most appropriate for three solid waste management scenarios was investigated (A1: material recycling facility + sanitary landfill; A2: material recycling facility + biological processes + sanitary landfill, and A3: thermal processes + biological processes + sanitary landfill) based on well-known solid waste management alternatives. Firstly, solid waste management scenarios were determined as decision points. Secondly, three solid waste collection options at the source (mixed: there is only one type of bin for all solid waste components; binary: paper + metal + plastic + glass, kitchen organics, and others; and triple: paper + metal + plastic + glass, kitchen organics, and others) were chosen as the main criteria affecting the decision points. Thirdly, fifteen sub-criteria were chosen based on the main criteria. In the process, not only the main and sub-criteria, but also stakeholders’ contributions are vital. For the pairwise comparison of all the criteria to be used in the study, the opinions of thirteen experts as stakeholders were obtained through face-to-face interviews. Within the scope of the zero waste vision, with a focus on environmental protection, the analytical hierarchy process was applied via pairwise comparisons of decision points and factors affecting the decision points. According to the results, in the case of mixed collection at the source, high preference rates were obtained for A1 as the decision point in terms of environmental (0.665), economic (0.699), social (0.510), and technical (0.544) criteria. In the case of binary separation at the source, A1 has high preference rates as the decision point in terms of environmental (0.553), economic (0.673), social (0.507), and technical (0.632) criteria. In the case of triple separation at the source, it is calculated that the A1 alternative has the highest preference values as the decision point in terms of environmental (0.558), economic (0.669), social (0.514), and technical criteria (0.611). Hence, the determining factor in the efficient integration of sustainable waste management with smart technologies is how waste is managed at the source. It is hoped that the results obtained in this study within the scope of the zero waste vision will assist decision-makers during sustainable municipal solid waste management processes. Full article

The Separately Collected Organic Fraction of Municipal Solid Waste (SC-OFMSW) is the biodegradable kitchen and canteen waste fraction that is separately collected at source and classified by the European Waste Catalogue under code 20 01 08. The utilization of SC-OFMSW Compost has emerged as a sustainable approach to enhancing agricultural soil quality and supporting soil biodiversity and productivity, while also serving as a viable option for disposing of treated urban waste. This study investigates the dose effect of SC-OFMSWC through phytotoxicity and growth assays in Arabidopsis thaliana and Lactuca sativa seeds and seedlings, as well as the impact of the same compost on the chemical and microbiological properties of soil under open field conditions. During the field trial in an agricultural orchard, soil pH, nutrient content, organic matter, and microbial activity following SC-OFMSWC and chemical fertilizer application were evaluated. In the greenhouse trial, a significant increase in germination rate and biomass production was found for L. sativa at a compost concentration of 2.5%, while neutral to negative effects were observed for A. thaliana. In the open field, results indicated significantly increased levels of organic carbon and enhanced microbial biomass and activity, accompanied by a general increase in nutrients, promoting soil health and resilience, with only limited increases in EC values and heavy metal content. These findings underscore the potential of SC-OFMSWC as an effective agricultural soil improver and a promising component in sustainable nursery management practices. Full article

Since the implementation of China’s mandatory waste sorting policy, the recycling of kitchen waste has become one of the core tasks of waste classification. The problem of designing the locations and the optimization configuration strategy for kitchen waste transfer stations faces great challenges in reconstructing the municipal solid waste collection and transportation system. This paper establishes an integer programming model for the bi-objectives of the location and optimal configuration for a kitchen waste transfer station, with the goal of minimizing the total cost and overall negative environmental impact. An improved non-dominated sorting genetic algorithm with an elite strategy (NSGA-II) is used to solve the problem, resulting in a Pareto-optimal solution set that includes several non-dominated solutions, thereby providing diversified choices for decision-makers. Finally, a pilot case involving cooperative enterprises is used as an example in this study, and the results demonstrate the effectiveness of the model and algorithm, as well as their feasibility in practice. Full article