Solid Waste Production Research Articles

Political factors and efficiency in the responsible production of municipal solid waste services: A dynamic DEA with a network structure approach

The production of municipal solid waste (MSW) is driven by socioeconomic development and population growth. In this context, public policymakers, mainly in developing countries, are increasingly focused on ensuring sustainable production and consumption patterns through sustainable management and efficient use of resources. Because of this, we seek to contribute to the effectiveness of public policies and the role of managers in achieving the global Sustainable Development Goals 3, 6, 11, and 12. This study examines the relevance of political and contextual factors on the dynamic efficiency of the network structure of municipal solid waste services in Brazil. We used Dynamic Data Envelopment Analysis with Structure Network to calculate the overall efficiency and specific efficiency of the two proposed divisions: operational and economic. We then analyzed the effects of years in political cycles (pre-election, election year, post-election) and contextual factors (ideology, GDP, density, transfers, political size, and geography) on MSW efficiency using Generalized Estimating Equation. The dataset included longitudinal panel data from 218 MSW from 2012 to 2022. Our results showed an average efficiency score of 57.5 %, with only six MSW positioned on the efficiency frontier. Evidence of stagnation in the sector's productivity was also revealed, undermining the goals and objectives of public policies. The results suggest that the years within political cycles significantly impact sector operator efficiency before, during, and after the electoral period. Specifically, lower levels of efficiency are observed during election years, suggesting potential opportunistic behavior throughout most periods of the electoral cycle. The main contribution of this work lies in its analysis of the different periods of a political cycle, and role of capital and ideological politics in intertemporal efficiency across two divisional networks.

Destructive Effects of Slag from Municipal Waste Incineration Plants on Cement Composites.

The increasing production of solid waste and the scarcity of natural aggregates as a matter of fact have made waste recycling a necessity. One such waste, which is generated in large quantities, is slag. However, slag from incineration plants may contain harmful elements that adversely affect the physical, chemical and mechanical properties of cement composites. This study presents laboratory research results on the effect of slag from the Poznan Municipal Waste Thermal Conversion Plant (Poland) on the physicochemical properties of cement composites. The samples were analyzed by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). It was shown that the slag analyzed contained significant amounts of aluminum, which had a direct effect on the structure of the concrete. An example of this influence is the release of hydrogen during reactions, which causes swelling and cracking of the concrete and reduces its mechanical strength. The authors emphasize that waste aggregate (slag) can be effectively used in the production of concrete after appropriate processing that reduces the risk of adverse effects.

FOSSIL FUEL EMISSION PREDICTION SYSTEM USING MULTIPLE KERNEL GAUSSIAN PROCESS

<p>According to the United States Environmental Protection Agency, 81% of greenhouse gas emission is due to Carbon-dioxide. When fossil fuels, solid waste, trees, and wood products are burnt, Carbon-dioxide emission occurs. The concentration of Carbon-dioxide in the atmosphere is reduced when it is absorbed by plants as a part of the biological carbon cycle. The major sources of CO2 emission are from fossil fuel such as coal, natural gas, oil, cement production, gas flares used in industrial plants and bunker fuels used in ships. Increase in CO2 emission leads to the increase in global warming. Climate change, change in seasonal events and decrease in agricultural productivity are the major impacts of global warming. Hence it is important to study and analyse CO2 emission based on the recorded data across the globe. Further the major source of emission must be detected and alert messages must be sent to the pollution control boards in various countries to take necessary remedial actions. This work focuses on predicting the CO2 emission in the near future in various countries based upon the “Fossil-Fuel CO2 Emissions by Nation” dataset recorded by Carbon Dioxide Information Analysis Center (CDIAC), Oak Ridge National Laboratory. This system comprises of data cleaning, data normalization, optimization, and model building. The model built using Multiple Kernel Gaussian Process (MKGP) will predict the concentration of CO2 that may be present in the atmosphere in upcoming years. Based on the prediction the major source of CO2 emission is identified. We have studied the effects of Radial Basis Function kernel, Rational Quadratic, Periodic kernel and combinations of the kernels on India USA and China dataset. We have proposed a Multi-Kernel Gaussian Process for predicting the fossil fuel emission (MKGP - FFE). It has been inferred that combination of kernels performed well when compared to individual kernels in most of the cases.</p>

An Optimization Framework for Waste Treatment Center Site Selection Considering Nighttime Light Remote Sensing Data and Waste Production Fluctuations

As urbanization accelerates, the management of urban solid waste poses increasingly intricate challenges. Traditional urban metrics, such as GDP and per capita consumption rates, have become inadequate for accurately reflecting the realities of waste generation; moreover, the linear correlation between these metrics and waste production is progressively diminishing. Consequently, this study introduces a novel methodology leveraging nighttime light remote sensing data to enhance the precision of urban solid waste production forecasts. By processing remote sensing data to mitigate noise and integrating it with conventional urban datasets, an innovative index system and predictive model were developed. Using Beijing as a case study, the gradient boosting regression algorithm yielded a prediction accuracy of 92%. Furthermore, in light of the substantial costs associated with waste recovery route planning and site selection for treatment facilities, this research further devised a location and distribution framework for waste treatment centers based on high-precision predictions of waste production while employing multi-objective evolutionary algorithms (MOEAs) alongside the non-dominated sorting genetic algorithm II (NSGA-II) for optimization. Distinct from prior studies, this study suggests that service point waste quantities are not fixed values but rather adhere to a normal distribution within specified ranges and thus provides a more realistic simulation of fluctuations in waste production while enhancing both the robustness and predictive accuracy of the model. In conclusion, by incorporating nighttime light remote sensing data along with advanced machine learning techniques, this study markedly improves forecasting accuracy for waste production while offering effective optimization strategies for site selection and recovery route planning—thereby establishing a robust data foundation aimed at refining urban solid waste management systems.

Converting lignocellulosic biomass into valuable end products for decentralized energy solutions: A comprehensive overview

This review manuscript delves into lignocellulosic biomass (LCB) as a sustainable energy source, addressing the global demand for renewable alternatives amidst increasing oil and gas consumption and solid waste production. LCB, consisting of lignin, cellulose, and hemicellulose, is versatile for biochemical and thermochemical conversions like anaerobic digestion, fermentation, gasification, and pyrolysis. Recent advancements have led to a 25 % increase in bioethanol yields through alkali pre-treatment and optimized fermentation, a 20 % enhancement in microbial delignification efficiency, and a 35 % improvement in enzyme efficiency via nanobiotechnology. These innovations enhance biofuel production sustainability and cost-effectiveness. Decentralized energy systems utilizing locally produced biomass can reduce transmission losses and greenhouse gas emissions by up to 30 %, fostering community energy independence. These developments significantly contribute to global sustainability and socio-economic development by converting waste into valuable energy, promoting environmental stewardship, and supporting economic resilience. Furthermore, this review also discusses innovative strategies to address technological, economic, and environmental challenges and highlights the role of decentralized solutions in promoting sustainable energy production.

Optimizing Syngas Production from Municipal Solid Waste Gasification: A Dual Reactor Fluidized Bed Study with Steam and CO2 as Gasification Agents

The escalating production of municipal solid waste (MSW) poses significant environmental and health hazards due to air, water, and soil pollution. Utilizing MSW as an energy source through gasification offers a promising solution to mitigate these impacts. This study investigates the gasification of MSW using a Dual Reactor Fluidized Bed, a thermal technology that converts solid substrates into usable gaseous fuels. The primary objective is to optimize the quality of the produced syngas by employing specific gasification agents, namely steam and CO2, and their mixtures. The research examines the effect of these agents on H2/CO ratios across a wide range of low operating temperatures, from 400°C to 700°C, using silica sand as a heat conduction medium between interconnected combustion and gasification reactors. The results demonstrate that the composition of syngas is strongly influenced by gasification temperature fluctuations. Increasing temperatures from 400°C to 700°C correlate with higher concentrations of CO and H2 in the syngas. The use of steam as a gasification agent yields H2 concentrations up to 25%, while transitioning from steam to CO2 leads to a substantial increase in CO composition, reaching 22.73%. Further analysis reveals that the H2/CO ratio decreases from 1,78 with steam and 0.64 with CO2, highlighting the crucial role of gasification agents in syngas quality. This study underscores the potential for optimizing syngas production from MSW by manipulating gasification temperatures and transitioning between different agents (steam, CO2, and their mixtures), resulting in an overall increase in the calorific value of the produced gas. These findings emphasize the opportunity to transform substantial environmental challenges associated with MSW into promising sustainable energy solutions through advanced gasification technologies.

Investigations into Biomass Utilization: A Renewable Alternative Fuel for Sustainable Energy

Indian municipal solid waste production exceeds 55 million tonnes per year, with a five percent yearly growth. Municipal solid waste has several environmental benefits, making it a promising feedstock for large-scale energy production. For energy utilisation, consider pelletising municipal solid waste with or without a binder. The volume of municipal solid trash created causes deposition, degradation, and maintenance concerns. India is increasing rapidly in population and urbanisation. This has consistently increased municipal solid trash production. The Planning Commission of India reports that 51% of Indian municipal solid trash is organic. Yard debris and food waste from restaurants, hotels and retail stores make up most of it. Since one-third of food is wasted, it's a major concern. One billion and three hundred thousand tonnes of food waste are produced worldwide. Municipal trash is dumped at open dumps in India. Open dumping is the least recommended method of solid waste management because it emits greenhouse gases and produces foul odours, flies, and rats, which spread disease and cause complaints in nearby residential areas. The spilt leachate may also affect nearby ground and surface waterways. Open dumps also need land, which is scarce in densely populated India. This is a major issue in India because landfills are open dumping sites without engineering solutions. Compared to anaerobic digestion and biomass gasification, pelletisation is a better organic waste treatment. Pelletisation is easy if wastes are categorised. After separation, garbage is treated and turned into pellets for burning. This study examines sixteen samples for calorific value, moisture, ash, and CHNS ratio. Energy crops, agricultural trash, forestry waste, and municipal garbage are samples.

Experimental and performance analysis of organic fraction of municipal solid waste in downdraft gasifier

It is anticipated that the production of municipal solid waste will increase from 2.10 billion tonnes in 2023 to 3.80 billion tonnes by 2050. About 170 billion metric tonnes of biomass is produced worldwide each year. On a wet basis, the composition of municipal solid waste (MSW) includes approximately 20% of wood, 70% of food waste, 60% of yard trimmings, and 50% of other organic materials. Gasification of waste biomass is one of the most efficient processes for creating gaseous fuel and subsequently power with reduced environmental impact. The current work presents a novel strategy to reduce MSW by converting waste into briquettes and feeding it in gasifiers to produce syngas. The downdraft gasifier is employed in the syngas generation process. With a calorific value of 22.6 MJ/kg and a higher lignin concentration of approximately 31%, MSW proves to be suitable for thermochemical conversion processes. This article presents the results during gasification of briquette made from organic fraction of municipal solid waste (OFMSW) with significant heating value of 22.6 MJ/kg. The fuel produced by the gasifier has a heating value ranging from 920 to 1150 kcal/m3, making it clean-burning. Its primary components consist of 19% to 23% carbon monoxide and 17% to 21% hydrogen. This study offers a unique investigation into the gasification behavior of the organic fraction of OFMSW in a downdraft gasifier, with an emphasis on optimizing operational parameters and evaluating the yield and quality of syngas. Although gasification has been widely studied as a thermochemical conversion method for biomass, the specific performance of OFMSW in this process has received limited attention. By focusing on this underexplored area, the study enhances the understanding of OFMSW's potential in gasification and its contribution to sustainable energy production, thereby addressing key issues in both waste management and renewable energy generation.

In-Vessel Aerobic Composting of Organic Waste Using Synthetic and Natural Bulking Agents

The escalating growth in municipal solid waste production underscores the imperative need for efficient waste management, especially given that a substantial portion of MSW comprises biodegradable materials suitable for composting. This study investigates the impacts of using a synthetic bulking agent (perforated plastic balls) in conjunction with biochar, a natural bulking agent, on the aerobic composting of kitchen waste. The study aim to evaluate the effectiveness of this combined approach in optimizing the composting process. Four trials, each spanning 30 days, were conducted to assess the effects of different combinations of synthetic and natural bulking agents. The study uses a uniform-size perforated synthetic bulking agent in combination with biochar to enhance the composting process. Results indicate that incorporating the perforated plastic balls (8% by weight) alongside biochar significantly influenced key composting parameters. This approach accelerated the initial rise in temperature to 55°C, enhanced the reduction of total organic carbon, improved total Kjeldahl nitrogen retention, and facilitated the achievement of optimal carbon-nitrogen (C/N) ratios ranging from 19 to 20. Furthermore, the analysis of phosphorus (P) and potassium (K) loss during composting revealed that potassium is more susceptible to leaching than phosphorus due to its higher mobility. The study concludes that the addition of a uniform-size perforated synthetic bulking agent, constituting 8% (by weight), in conjunction with a natural bulking agent, effectively enhances the composting process.

Optimizing municipal solid waste management in industrial ports: A case study of source separation implementation

ABSTRACT With the acceleration of industrialization and population growth, there has been a notable surge in municipal solid waste (MSW) production globally. This necessitates the development of efficient waste management strategies that align with sustainable economic, environmental, and social goals. Implementing sorting and source separation policies serves as foundational steps toward optimizing material flow and resource utilization. In industrial areas, waste generation around a primary source may improve policy implementation and participation. Given the unique strategic context of port environments, Bahregan Port in Iran was selected as a case study to evaluate the proposed methodology. Three integrated scenarios were formulated and prioritized using the ELECTRE-I model: currently practiced collection method, and segregated collection followed by source separation of MSW into two or three groups. The analysis identified the third scenario as the most effective approach. Remarkably, when evaluating the results under optimistic and pessimistic conditions, the ranking of preferences remained consistent across scenarios in the optimal state. Under pessimistic conditions, all scenarios received identical scores, indicating significant uncertainty in criteria weights. Furthermore, sensitivity analysis revealed that criteria such as the raw material sources protection, emissions in the waste separation sector, and greenhouse gas emissions were highly influential. Interestingly, criteria with the highest weighting did not always dictate the final scenario selection. External factors, such as expert opinions on specific criteria, played a pivotal role in scenario prioritization. This research serves as a foundational study for source separation initiatives, offering practical and technically viable strategies to enhance environmental sustainability within industrial settings. Implications Statement Rising industrialization and population growth have led to increased municipal solid waste (MSW) production worldwide. To address this, efficient waste management strategies are essential, focusing on sustainability and resource optimization through sorting and source separation policies. By prioritizing the scenario of segregated collection followed by source separation – industrial areas can optimize material flow and resource utilization. The study highlights the influence of criteria like raw material protection, emissions, and greenhouse gases, making this research foundational for enhancing environmental sustainability in industrial settings. This study provides practical strategies for enhancing environmental sustainability in industrial settings through source separation initiatives.

Fabrication and characterization of low-cost ceramic membranes from coal fly ash and natural sand

Coal fly ash, an industrial solid waste product, and natural sand, a commonly available and inexpensive natural material, were used to fabricate ceramic membranes that are both affordable and sustainable. These ceramic membranes were fabricated by the uniaxial compaction technique using a manual hydraulic pressing machine. The effects of various fabrication parameters such as the sintering temperature and the amount of natural sand utilized, on the properties of the resulting ceramic membranes were extensively evaluated. X-ray fluorescence (XRF) analysis of the starting materials confirmed the presence of SiO2 and Al2O3, two key inorganic materials required for the fabrication of ceramic membranes. Heavy metals present in the raw coal fly ash were leached out prior to the fabrication process. The coal fly ash and natural sand were mixed in different proportions and the fabricated ceramic membranes were characterized using Fourier transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM), X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDS), and Thermogravimetric analysis (TGA). The properties of the optimized membranes were further studied to ascertain their mechanical strength, chemical stability, porosity, water absorption, water permeability, and shrinkage behaviour. The membrane fabricated with 20 wt% sand content and at 1000 °C sintering temperature had pore size of 0.64 µm and 34.7 % porosity, exhibited good mechanical strength (7.71 MPa), and exceptional chemical stability. The membrane also showed a remarkable water permeability of 32.23 L/m2/h. This study showed that natural sand and coal fly ash can be efficiently employed to develop a multifunctional filtration membrane with adjustable properties that can be utilized in water purification.

The proximate composition of vegetables enriched by incorporation of municipal solid waste into fertilizers and its impacts on environment and human health

The recent over production of municipal solid waste (MSW) poses a significant threat to both the ecosystem and human health. Utilizing MSW for agricultural purposes has emerged as a promising strategy to reduce solid waste disposal while simultaneously increasing soil fertility. To explore this potential solution further, an experiment was designed to assess the impact of varying concentrations of MSW (25%, 50%, and 75%) on the proximate composition of 15 different vegetable species. The experiment, conducted between 2018 and 2019, involved treating soil with different levels of solid waste and analyzing the proximate components, such as crude protein, dry matter, crude fiber, crude fat, and moisture content, in the 15 selected crops. The results indicate that the application of 25% MSW significantly increased the levels of crude protein, crude fiber, dry matter, and fat in Spinacia oleracea, Solanum tuberosum, Solanum melongena, and Abelmoschus esculentus. Conversely, the addition of 75% MSW notably elevated the moisture and ash content in Cucumis sativus. Correlation and scatter matrix analyses were conducted to elucidate the relationships between the protein, fiber, dry matter, ash, and fat contents. Principal component analysis and clustering confirmed the substantial impact of Treatment_1 (25% MSW) and Treatment_3 (75% MSW) on the proximate composition of the aforementioned vegetables, leading to their categorization into distinct groups. Our study highlights the efficacy of using 25% MSW to enhance the proximate composition and nutritional value of vegetables. Nonetheless, further research is warranted to investigate the mineral, antioxidant, vitamin, and heavy metal contents in the soil over an extended period of MSW application.

Assessing the potential of olive mill solid waste as feedstock for methane and volatile fatty acids production via anaerobic bioprocesses

The extensive production of olive mill solid waste (OMSW) from olive oil industry in the Mediterranean basin claims effective treatments and valorization strategies. This study aims to elucidate the potential of anaerobic digestion (AD) and anaerobic fermentation (AF) to convert pre-treated OMSW into biogas (CH4) and volatile fatty acids (VFA), respectively. The two thermal treatment conditions (65 °C and 180 °C) that are being implemented in the industry that manages the OMSW were tested. Comparing the two treatments aims to demonstrate the influence on the AD process of the degree of solubilization and degradation of the metabolites produced from the same substrate. AD of OMSW treated at low-temperature (65 °C) exhibited similar methane yields (195 ± 8 mL CH4/g volatile solid (VS)) to raw OMSW. AD of the solid phase (SP) after high-temperature treatment with acid addition at 180 °C resulted in methane yields comparable to raw OMSW while the liquid phase (LP) exhibited low methane yields (85 ± 10 mL CH4/g VS). Nevertheless, LP/180 °C exhibited the highest VFA bioconversion at 27.6 %, compared to less than 10 % for SP/180 ºC, SP/65 °C, and raw OMSW. The VFA profile showed notable variations with thermal treatment temperatures. Propionic acid dominated at SP/65 °C, while acetic acid became the primary VFA at 180 °C. Furthermore, significant degradation rates of phenolic compounds and furans were observed during the final day of both anaerobic processes. Overall, these findings suggest that AD is more suitable for raw OMSW, treated at low temperature and SP at high temperature, while AF offers a promising alternative for high-temperature-treated LP.

Urban digital twin-based solution using geospatial information for solid waste management

With over 2 billion metric tons generated annually, global solid waste production has severe environmental consequences. Although it is not a primary Sustainable Development Goal, effective solid waste management (SWM) is vital for meeting targets 11.6, 12.4, and 12.5. South Africa, in particular, deals with significant SW generation and inadequate collection services. Therefore, this paper presents an Urban Digital Twin (UDT) prototype to tackle these issues, involving stakeholder prioritization, integrating real-time monitoring, citizen participation, waste generation simulations, optimized collection routes, and a control Dashboard where stakeholders’ system requirements were included. The UDT proposes optimized collection routes to reduce fuel use, operational costs, and emissions. The stakeholders’ opinions on the usefulness of the UDT varied due to their backgrounds and skills. Most of them appreciated the Dashboard visualization and the UDT possibilities for resource optimization. The performance of the UDT depends on computer capacity and local or online processing. This UDT prototype sets the foundation for digital twinning in SWM, scalable to different areas, vehicles, and production levels. The proposed approach, citizen involvement, and multi-stakeholder engagement enhance the SWM, benefiting resource-limited countries.

Optimization of a proposed biomass generator: Harnessing citizen waste with electric vehicle charging infrastructure

Global municipal solid waste production is rising, causing significant environmental, health, and economic issues. Developed countries have advanced recycling technologies, but cities like Dhaka, Bangladesh—among the most densely populated-struggle with inadequate waste management. This feasibility study aims to improve environmental protection and create new energy sources by proposing a waste management system across Dhaka, focusing on waste valorization for bioenergy with optimized efficiency and minimal impact. The study includes design and optimization of a biomass-based power plant to meet the energy needs of EV charging stations and the national grid, evaluating its economic performance through discounted cash flow and payback period analyses. The paper explores the integration of an EV charging station powered by biogas, addressing the growing need for EV infrastructure in Dhaka. By evaluating biomass generators as a greener alternative to fossil fuels, the study analyzes the technical, economic, and environmental feasibility, including CO2 emissions, using HOMER Pro.

Assessing Health and Environmental Risks: Educational Awareness on Plastic Usage and Solid Waste Disposal in Bahawalpur

The review paper explores the increasing challenges posed by plastic pollution and improper solid waste management in Bahawalpur. The population has continued to increase, and there is ever-increasing urbanization; this has contributed to the increase in plastic and solid waste production, such as the single use of plastic bags and bottles. These waste materials contribute to environmental degradation, affecting soil quality and contaminating water systems. Improper disposal contributes to public health challenges like respiratory and waterborne diseases and vector-borne ailments like malaria and dengue fever. A fully equipped waste management framework is needed to solve more problems in Bahawalpur; this leads to a filled drainage system, urban flooding, and the discharge of hazardous wastes. The review also explains the level of community health education used to ensure sustainable waste management practices are practiced. Hence, the paper encourages the involvement and expansion of community-based programs and public or private-founded collaboration to support and practice recycling and the appropriate management and minimization of single-use plastics. Smart solutions are also briefly touched upon as potential solutions, including implementing waste-to-energy plants and smart bins. Consequently, this review calls for enhanced stewardship, more specific to public sensitization against further pollution of Bahawalpur and other similar urban settings by plastic and solid waste.

Porous hollow microspheres based on industrial solid waste enhance biomethane recovery from corn straw

The increasing production of industrial solid waste requires better disposal solutions. Porous hollow microspheres (PHM) are small inorganic materials with high surface area and adsorption capacity, but their potential for use in anaerobic digestion (AD) has not been explored. With PHM as additive, the effects of different industrial solid wastes (waste glass, steel slag, and fly ash) with different loadings (2 %–8 %), respectively, on the AD of corn straw were investigated in this study. The results showed that PHM could supplement trace elements and promote biofilm formation, which effectively shortened the lag period (25.00–60.87 %) and increased the methane yield (4.75 %–16.28 %). The 2 % PHM loading based on steel slag gave the highest methane yield (300.16 NmL/g VSadd). Microbial and PICRUSt2 analyses indicated that PHM enriched hydrolytic and acidogenic bacteria, increased the abundance of methanogenesis-related enzyme genes. This study provides a theoretical basis for the comprehensive utilization of coupled industrial and agricultural wastes.

Energy-saving and benign hydrogen production by coal gasification fine slag-assisted Water electrolysis

ABSTRACT Integrating anodic coal gasification fine slag oxidation with cathodic hydrogen evolution reaction presents an environmentally friendly and energy-efficient solution for solid waste recycling and hydrogen production. This innovative approach exhibits higher activity and stability than conventional water electrolysis, while also preventing anode degradation due to its benign reaction conditions. The kinetic investigations have revealed that slag oxidation occurs more rapidly than water oxidation. Specifically, slag undergoes direct and indirect oxidation within the potential regions below and above those of water oxidation, respectively. This study has the potential to shed light on the mechanisms underlying slag electrolysis and offer valuable insights for the simultaneous recycling of solid waste and hydrogen production.

Models for estimating solid waste production in hospitality establishments in João Pessoa, Brazil

Municipalities are responsible for solid waste management in urban areas, from collection to final treatment, in case the waste produced by economic agents is not dangerous. In the scope of economic activities, tourism has been growing strongly, especially in Brazilian coastal urban areas. In this sense, a larger production of urban solid waste is one of the main effects of the development of the hospitality sector. This study aims to design models to estimate the production of solid waste in hospitality establishments. This research object refers to a sample of 7 hotels in the city of João Pessoa, Brazil. Solid waste generated by the hotel sector in the city of João Pessoa was estimated by developing linear regression models. The models showed that 71% of the waste refers to the number of guests, number of employees, and services offered in the hotel. Results indicate an estimated solid waste generated by hotel establishments in the city of João Pessoa of 4,148 kg.day-¹, out of which 59.2% are organic waste, 21.8% are recyclable, and 18.9% are non-recyclable.

Reuse potential of municipal solid waste incinerator bottom ash as secondary aggregate: Material characteristics, persistent organic pollutant content and effects of pH and selected environmental lixiviants on leaching behaviour

Increasing municipal solid waste (MSW) production poses challenges for sustainable urban development. Modern energy-from-waste (EfW) facilities incinerate MSW, reducing mass and recovering energy. In the UK, MSW incineration bottom ash (MSW IBA) is primarily reused in civil engineering applications. This study characterizes UK-produced MSW IBA, examining its pH-dependent leaching behaviour and response to environmental lixiviants. Results show predominant components include a melt phase, primary glass and fine ash aggregations, and a chemical composition dominated by SiO2 (30–50 %), CaO (∼15 %), Fe2O3 (∼10 %), and Al2O3 (∼8%). X-ray absorption near edge structure (XANES) analysis shows that Zn and Cu are most likely oxygen-bound (adsorbed to oxy-hydroxides and as oxides) with some sulphur bound. Polychlorinated biphenyls (PCBs) and polychlorinated dibenzodioxins/furans (PCDD/Fs) are well below regulatory limits, and polycyclic aromatic hydrocarbons (PAHs) were undetectable. Leaching tests indicate trace elements mobilize at pHs ≤ 6. With a natural pH of 11.3 and high buffering capacity, significant acid inputs to the MSW IBA are required to reach this pH, which are improbable in the environment. Wood chip additions increase leachate’s dissolved organic carbon (DOC) and reduce pH, but had minimal impact on metal-leaching behaviour. Synthetic plant exudate solutions minimally affect metal leaching at realistic concentrations, only enhancing leaching at ≥ 1500 mg l−1 DOC. This work supports MSW IBA’s low-risk in specified civil engineering applications.