Municipal Solid Waste Materials Research Articles

Refuse-derived fuel (RDF) production and analysis in mechanical-biological treatment (MBT) plant from the municipal solid waste

This study reports on the potential of refuse-derived fuels (RDF), which are produced from Sulaimani Municipal solid waste (MSW) using a biodrying process. Plastic, organic wastes, iron materials, and textiles were used in the formulation of RDF samples. A sample of raw MSW material was collected comprising of 40.6% organic, 29.3% plastic, 6.3% Textiles, 5.1% paper, 3.1% wood, 4.6% glass and stone, 5.2% iron containing materials, and 1.3% others. Physical and chemical properties of the RDF were investigated, including its moisture, ash, total chlorine, and heavy metal content with, calorific value. Based on the experimental results, RDF produced from MSW can be classified into net calorific and total chlorine content values NCV 2 and Cl 4 respectively. In accordance with the European Committee for Standardization (CEN standard), the results of this preliminary investigation of RDF samples made from non-biodegradable and non-recyclable MSW fractions, is necessary to analyze a larger pool of samples in order to project appropriate RDF energy-recovery-enhancing composition.

Cobalt Uptake by Food Plants and Accumulation in Municipal Solid Waste Materials Compost-amended Soil: Public Health Implications.

One of the most pressing environmental issues is how to properly dispose of municipal solid waste (MSW), which represents both a substantial source of concern and a challenge. The current study evaluated cobalt (Co) accumulation in MSW, their uptake by different vegetables grown for two years, and related human health risks. Vegetables were grown in four different groups, such as one control (ground soil), and the remaining treatment groups (T1, T2, and T3) received varying concentrations of MSW. The analysis of Co was done through an atomic absorption spectrophotometer (AAS). Results revealed that the concentration of Co was higher in all the vegetables (n = 15) grown in soil supplemented with 75% MSW during 2nd growing year. Among all vegetables, the highest concentration of Co was observed in Solanum tuberosum at T3 during 2nd growing year. The pollution load index (PLI) value for vegetables during both growing years was more than 1 except in control soil. The findings indicated that the highest enrichment factor (EF) and hazard resilience index (HRI) value of 0.09 was present in S.tuberosum. Health index values for cobalt in the study were below 1. The HRI < 1 indicated that consumers do not face any immediate health risks. The investigation of Co concentrations in blood samples obtained from individuals residing in different areas contributes a human health perspective to the research. The findings indicate that the concentration of Co rises with an increasing proportion of MSW. While the metal levels in MSW-treated soil were not high enough to classify the soil as polluted, the results recommend that recycling MSW can substitute mineral fertilizers. Nevertheless, the presence of cobalt in MSW may directly affect soil fertility and could impact crop production and human health.

Advances in Corrosion Mitigation for Waste-to-Energy Systems: Evaluating Coatings and Application Techniques

Waste-to-Energy (WTE) systems, utilizing post-recycled municipal solid waste (MSW) and other biomass materials, are proven alternatives to landfilling for sustainable waste management. These processes offer benefits such as reduced landfill space, decreased methane emissions, and minimized waste volume. However, operational challenges, specifically high-temperature corrosion (HTC) of superheater tubes, hinder their efficiency due to the presence of chlorine, alkaline salts, and sulfates. To address this issue, a range of coating techniques have been developed, with thermal spray techniques, particularly high velocity oxy-fuel (HVOF) spray, proving the most effective for protecting superheater tubes. A comparative analysis of experimental data from multiple studies indicates that coatings with Alloy 625, Alloy C-276, Colmonoy 88, FeCr, IN625, NiCr, NiCrTi, and A625 offer high corrosion resistance at relatively low material costs, with corrosion rates below 1 mm/year. High chromium, nickel, and molybdenum content coatings perform exceptionally well under high-temperature and high-chlorine conditions. Notably, T92 and P91, due to their low cost and high corrosion resistance, are strong candidates for superheater tubes operating at 550°C. While A625 demonstrates excellent corrosion resistance, its high cost limits its practicality. Ultimately, the selection of suitable coatings depends on the specific WTE plant design and operating experience. The additional cost of applying these coatings is a minor fraction of the overall financial gains, as it extends the superheater tubes' lifetime and reduces plant downtime for tube repair or replacement.

Research on the Preparation of Biochar from Waste and Its Application in Environmental Remediation

Biochar is a carbon-rich material that can be composed of a variety of raw materials. From the perspective of resource reuse, it is quite feasible to use waste as a raw material for the preparation of biochar. This paper provides an overview of the types of waste that can be used to prepare biochar and their specific substances, and also summarises methods to enhance or improve the performance of biochar, including physical, chemical, biological and other methods. The feedstock for biochar includes four categories: agricultural and forestry waste, industrial by-products, municipal solid waste and other non-traditional materials. This paper also summarises and classifies the role played by biochar in environmental applications, which can be classified according to its role as an adsorbent, catalyst and soil conditioner, and other applications. In addition to being widely used as an adsorbent, catalyst and activator, biomass charcoal also has good application prospects as a soil remediation agent, amendment agent and supercapacitor, and in soil carbon sequestration. Finally, some ideas and suggestions are detailed for the present research and experiments, offering new perspectives for future development.

Pore structure characteristics, mechanical properties, and freeze–thaw resistance of vegetation-pervious concrete with unsintered sludge pellets

To make full use of municipal solid waste, the sludge was used to make unsintered sludge pellets. Then unsintered sludge pellets was used to make vegetation-pervious concrete. The effects of the sludge pellet content and the water-to-cement ratio (W/C) on the pore structure characteristics, mechanical properties, ecological properties, and freeze–thaw resistance of the concrete were investigated. The results show that sludge is suitable for preparing pellets due to its good plasticity and high SiO2 and Al2O3 content. A 1:2:1 gypsum/fly ash/lime curing agent is selected to cure unsintered sludge pellets. The total porosity, hydraulic conductivity, ecological properties, and freeze–thaw resistance of the pervious concrete improve with an increase in the sludge pellet content and W/C, while its compressive and flexural strengths decrease. The plant roots penetrate the pervious concrete slab and maintain normal growth after 30 days of germination. In addition, a model considering the effective porosity and mean pore size is proposed for predicting the pore channel tortuosity of pervious concrete. The Kozeny–Carman model for calculating the hydraulic conductivity of pervious concrete is then modified based on the established calculation model of pore channel tortuosity. A model is also developed for predicting the compressive and flexural strength of pervious concrete based on its total porosity and mean pore size. In addition, the mechanism for the freeze–thaw resistance of pervious concrete is analyzed according to hydrostatic pressure. This research explains the full utilization of municipal solid waste materials and guides further research into the properties associated with pervious concrete.

Estimation of short-term settlements of MSW landfill materials using shear wave velocity

Limited availability of simple yet adequately validated tools for estimating the deformation potential of municipal solid waste (MSW) material poses difficulty in planning and managing landfill operations. Estimation of settlement of MSW landfills has remained a challenge because of heterogeneity and time-varying mechanical behavior of MSW materials and difficulty of extracting representative samples and reconstituting them for laboratory testing. An empirical correlation is proposed here for estimating the short-term settlement of landfill materials. The relationship was developed by calibrating laboratory data from axial (1D) compression and consolidated drained triaxial tests against field-measured shear wave velocities from five landfill sites with varied waste compositions. The correlation was validated against three full scale load tests; one obtained in this research and two reported by others, and a field compaction study from a fourth landfill. Although the proposed correlation was more accurate than an alternative developed earlier, overall it underestimated settlements by about 12%. The proposed relationship could therefore provide a conservative guidance in MSW landfill design and operation.

Development, exergoeconomic assessment and optimization of a novel municipal solid waste-incineration and solar thermal energy based integrated power plant: An effort to improve the performance of the power plant

Due to the growing population rate and increasing social activities, the content of municipal solid waste (MSW) production is increasing. Energy production from MSW is one of the promising ways to dispose of waste and reduce the limitations of fossil energies. However, this technology has a relatively low efficiency due to the high volume of moisture and inert materials in MSW and the lower heating value of waste. The integration of solar thermal collectors is one of the suggested solutions to increase the temperature of inlet steam to the power generation cycle in order to improve the power plant performance. In this regards, the present study develops a comprehensive thermodynamic-conceptual and exergoeconomic investigation of the performance of a MSW-incineration (MSWI) plant integrated with a parabolic trough collector (PTC)-based solar field. Accordingly, the temperature of the steam elevates by the solar field before entering the electric power generation cycle. Additionally, the solar unit is integrated with a phase change material (PCM)-based storage system. The use of storage tank at the delivery line of PTC can improve the power plant’s reliability. A comprehensive comparison of the developed power plant with the conventional MSWI power plant is presented. In addition, the technical and economic behaviors of the considered power plant have been optimized under two different single and multi-objective optimization scenarios. The outcomes indicated that the developed power plant can provide 15.75% and 15.68% higher energetic and exergetic efficiencies compared to MSWI power plant. In addition, the rate of electric power obtained from S-MSWI power plant is almost 16.1% more compared to MSWI power plant. However, the total cost rate of MSWI plant is almost 24.13% lower compared to the developed power plant. But, the value of LCOE in the developed power plant is approximately 8.93% lower than MSWI power plant. It was also found that, the multi-objective optimization can provide better and optimal results to energy engineers and decision makers compared the single-optimization. The conceptual design of the implementation of the solar field is also developed in a specific geographical condition. Additionally, this research comes from the key technology of the National Key Laboratory of Environmental Protection.

Processing renewable and waste-based feedstocks with fluid catalytic cracking: Impact on catalytic performance and considerations for improved catalyst design.

Refiners around the globe are either considering or are actively replacing a portion of their crude oil inputs originating from fossil sources with alternative sources, including recycled materials (plastics, urban waste, mixed solid waste) and renewable materials (bio-mass waste, vegetable oils). In this paper, we explore such replacement, specifically focusing on the fluid catalytic cracking (FCC) operation. Five pyrolysis oils, obtained from municipal solid waste (MSW) and biogenic material (olive stones/pits), were fully characterized and tested at 10% loading against a standard fluid catalytic cracking (FCC) vacuum gasoil (VGO) feed in a bench scale reactor using an industrially available fluid catalytic cracking catalyst based on ultrastable Y zeolite to simulate fluid catalytic cracking co-processing. Despite having unique feed properties, including high Conradson carbon (e.g., up to 19.41wt%), water (e.g., up to 5.7wt%), and contaminants (e.g., up to 227ppm Cl) in some cases, the five pyrolysis oils gave similar yield patterns as vacuum gasoil. Gasoline was slightly (ca. 1wt%) higher in all cases and LPG slightly (ca. 1wt%) lower. Olefinicity in the LPG streams were unchanged, bottoms and light cycle oil (LCO) showed no significant changes, while dry gas was slightly (up to -0.2wt%) lower. Coke selectivity was also unchanged (maximum -7.7wt%, relatively), suggesting minimal to no heat balance concerns when co-processing in an industrial fluid catalytic cracking unit. The results demonstrate the applicability of municipal solid waste and biogenic originating pyrolysis oils into a refinery. A catalyst design concept is explored, based on higher rare Earth oxide exchange and/or utilization of ZSM-5 zeolite, that would further minimize the impacts of replacing fossil oils with pyrolysis oils, namely one that shifts the 1% higher gasoline into LPG.

Recycling and Utilization Assessment of Municipal Solid Waste Materials to Stabilize Aeolian Sand

Recycling and Utilization Assessment of Municipal Solid Waste Materials to Stabilize Aeolian Sand

Characterization of Municipal Solid Waste and Assessment of Its Potential for Refuse-Derived Fuel (RDF) Valorization

Reuse and recycling are preferred strategies in waste management to ensure the high position of waste resources in the waste management hierarchy. However, challenges are still pronounced in many developing countries, where disposal as a final solution is prevalent, particularly for municipal solid waste. On the other hand, refuse-derived fuel as a means of energy recovery provides a sustainable option for managing mixed, contaminated and residual municipal solid waste (MSW). This study provides one of the earliest assessments of refuse-derived fuel (RDF) from MSW in Ghana through a case study in the cities of Accra and Kumasi. The residual/reject fractions (RFs) of MSW material recovery were characterized for thermochemical energy purposes. The studied materials had the potential to be used as RDF. The combustible portions from the residual fractions formed good alternative fuel, RDF, under the class I, II-III classification of the EN 15359:2011 standards. The RDF from only combustible mixed materials such as plastics, paper and wood recorded a significant increase in the lower heating value (28.66–30.24 MJ/kg) to the mass RF, with the presence of organics (19.73 to 23.75 MJ/kg). The chlorine and heavy metal content met the limits set by various standards. An annual RDF production of 12 to 57 kilotons is possible from the two cities. This can offset 10–30% of the present industrial coal consumption, to about 180 kiloton/yr CO2 eq emissions and a net cost saving of USD 8.7 million per year. The market for RDF as an industrial alternative fuel is developing in Ghana and similar jurisdictions in this context. Therefore, this study provides insights into the potential for RDF in integrated waste management system implementation for socioeconomic and environmental benefits. This supports efforts towards achieving the Sustainable Development Goals (SDGs) and a circular economy.

Life cycle analysis of gasification and Fischer-Tropsch conversion of municipal solid waste for transportation fuel production

Non-recyclable municipal solid waste (MSW) can be used as feedstock for liquid fuel production via gasification followed by Fischer-Tropsch (FT) processes. Given the heterogeneity of MSW material composition and variation in material properties, its convertibility to liquid hydrocarbon fuels could vary widely, affecting the sustainability of utilizing non-recyclable MSW for fuel production. This study evaluates the life cycle greenhouse gas (GHG) emissions (carbon intensities [CIs]) of FT fuels from non-recyclable MSW. Key issues that could greatly affect the CIs were examined, including fossil carbon content of the MSW, emission implications of diverting non-recyclable MSW from landfills to fuel production, and conversion efficiency. Results show that the CIs of fuels produced from various waste streams range 80–105 gCO2e/MJ, which may exceed the CI of petroleum fuels. Higher fossil carbon content in the MSW feedstock tends to incur higher GHG emissions as biogenic carbon emissions are considered carbon neutral. Meanwhile, diverting different fractions of non-recyclable MSW, such as food waste and low-quality paper, from landfills may result in GHG emissions that may include the potential avoidance of methane emissions and potential sequestration of biogenic carbon that is foregone. To reduce GHG emissions, a carbon capture and sequestration option in the fuel production stage is considered, which could reduce the CI by 53–64 gCO2e/MJ. Carbon fates of different non-recyclable MSW in landfills are further evaluated to determine how they vary and impact the CIs of MSW-derived fuels.

Towards a Framework for Sustainable Municipal Solid Waste Management: The Case of Swakopmund Municipality, Namibia

If municipal solid waste (MSW) is not properly managed, harmful environmental consequences are imminent. MSW materials are rarely wasted in many affluent countries, but rather are kept in the economic cycle through circular economy models. While in many developing countries, MSW materials are discarded with little to no effort of repairing or recycling. Moving to a circular economy will drastically reduce the amount of waste currently disposed of. This study examines how the Swakopmund Municipality in Namibia’s present municipal solid waste management techniques could be adjusted toward sustainability to reap environmental and socioeconomic benefits from the trash. Source reduction, separation at source, and recycling are some of the most effective strategies in the circular economy models that will help achieve the United Nations (UN) Sustainable Development Goals (SDGs). Swakopmund Municipality should invest in infrastructure, techniques, and programs that are within the circular economy model as an emerging system for sustainability.

POWER GENERATION USING WASTE MATERIALS BASED IOT APPROACH

Every developing country relies heavily on electricity. To meet the increased demand for electricity, many types of power plants are being created. The supplydemand imbalance is widening as natural resources are depleted. Power generation from industrial waste is critical for addressing the energy problem. This is one of the other solutions to the problem. This document was created as a solution and approach for generating power from solid waste materials (SWM). It plans to develop electrical energy power from Municipal Solid Waste Materials, transform that low electrical energy into higher electrical energy power, and charge mobile phones with the generated electricity. This article and its findings will be beneficial to the renewable energy industry.

Metal leaching from Lithium-ion and Nickel-metal hydride batteries and photovoltaic modules in simulated landfill leachates and municipal solid waste materials

• The end-of-life impacts of batteries and photovoltaics in landfills was examined. • TCLP guided tests indicated that some should be classified as hazardous waste. • Additional work is needed to develop appropriate EoL procedures for MSW with e-waste. Photovoltaic (PV) modules and batteries can either be recycled or disposed of in landfills at end-of-life (EoL). This work focuses on disposal since the benefit of recycling PV modules and batteries is well established. This study characterizes the potential toxicity due to metals leaching from selected PV modules and batteries through both the Toxicity Characteristic Leaching Procedure (TCLP) and in-house batch leaching protocols to probe the impact on metallic ion mobility as a function of the different types of e-waste entering the waste stream, the magnitude of device damage when placed into the waste stream, and the simulated municipal solid waste (SMSW) composition. Our results showed that one PV module and three battery types in this study should be classified as hazardous waste within the U.S. However, for some of the other e-wastes, metals of concern including Cr, Cu, Hg, Ni, Pb, and Zn leached during the batch tests but not in the TCLP regulatory method. For most of the waste types, the amounts of metals that leached in the TCLP test and batch tests were much lower than the total extractable amounts, demonstrating the potential for additional unaccounted for amounts of metals to leach. These results demonstrate that the TCLP regulatory method might fail at predicting potential leaching and at capturing the complexity of e-waste leaching in landfill conditions. It confirms that additional work is needed urgently to develop appropriate EoL procedures for MSW with PV and battery e-waste.

Machine learning models for prediction the Higher Heating Value (HHV) of Municipal Solid Waste (MSW) for waste-to-energy evaluation

Time-resolved knowledge of physico-chemical properties of Municipal Solid Waste (MSW) materials and their thermal energy content is one of the important subjects needed to build waste incineration power plants around the world. For this purpose, machine learning models were used to predict the Higher Heating Value (HHV) of MSW based on the initial materials. Four types of machine learning methods: Radial Bias Function Artificial Neural Network (RBF-ANN), Multilayer Perceptron Artificial Neural Network (MLP-ANN), Support Vector Machine (SVM) and Adaptive Nero-Fuzzy Inference System (ANFIS) were used for modeling the HHV with six different inputs (carbon, water, hydrogen, oxygen, nitrogen, sulfur, and ash). The results showed that RBF-ANN can predict the HHV of MSW with higher accuracy than other models. The overall Mean Absolute Percentage Error (MAPE) for MLP-ANN, SVM and ANFIS models were 7.3, 11.77 and 23.76%, respectively. The MAPE of the best topology for RBF model (6-17-1) with spread factor of 0.8 reach to 0.45%. Finally, the results of this study proved that ANN's can be used as a practical tool with high accuracy and reliability for design and management of waste incineration plants.

Solid Waste Management in the Context of a Circular Economy in the MENA Region

Solid waste management in most MENA countries is characterized by lack of planning, improper disposal, inadequate collection services, inappropriate technologies that suit the local conditions and technical requirements, and insufficient funding. Therefore, waste management is mainly limited to collection, transportation, and disposal. As the circular economy has recently been given high priority on the MENA region’s political agenda, all MENA member states are seeking to move away from old-fashioned waste disposal, “waste management”, towards a more intelligent waste treatment, “resource efficiency”. This paper presents a comprehensive overview of national systems for municipal solid waste (MSW) management, and material and energy recovery as an important aspect thereof, in the context of the circular economy in selected countries in the MENA region. Since policy, regulation, and treatment technologies are traditionally connected to MSW management, the focus of this article is twofold. Firstly, it aims to identify the different practices of solid waste management employed in selected MENA region countries and their approaches to embracing the circular economy and, secondly, it examines the extent to which policies and technologies applied play any role in this context. The study revealed that most waste management issues in the countries analyzed appear to be due to political factors and the decentralized nature of waste management with multi-level management and responsibilities. In fact, material and energy recovery in the context of municipal solid waste management does not differ significantly in the countries in the MENA region considered. In most cases, “waste” is still seen as “trouble” rather than a resource. Therefore, a fresh vision on how the solid waste management system can be transformed into a circular economy is required; there is a need for paradigm shift from a linear economy model to a circular-economy model.

Utilization of Municipal Solid Waste (MSW) Materials in Various Civil Engineering Works

Utilization of Municipal Solid Waste (MSW) Materials in Various Civil Engineering Works

Development of Reaction Kinetics Model for the Production of Synthesis Gas from Dry Methane Reforming

The energy supply systems dependent on fossils and municipal solid waste (MSW) materials are primarily responsible for releasing greenhouse (GHG) gases and their related environmental hazards. The increasing amount of methane (CH4) and carbon dioxide (CO2) is the scientific community's main concern in this context. Reduction in the emission amount of both gases combined with the conversion technologies that would convert these total threat gases (CO2 and CH4) into valuable feedstocks will significantly lower their hazardous impact on climate change. The conversion technique known as dry methane reforming (DMR) utilizes CO2 and CH4 to produce a combustible gas mixture (CO+H2), popularly known as synthesis gas/or syngas. Therefore, this research study aims to explore and enlighten the characteristics of the DMR mechanism. The conversion behaviour of CO2 and CH4 was studied with modelling and simulation of the DMR process using MATLAB. The results showed that inlet gas flow has a significant impact on the reactions. In contrast, the inlet molar composition ratio of the reactions was found to have no substantial effect on the mechanism of DMR. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Mechanical-biological treatment of municipal solid waste: Case study of 100 TPD Goa plant, India

A long-term feasibility analysis of a 100 ton per day mechanical biological treatment (MBT) plant for municipal solid waste (MSW) valorization and material and energy recovery was carried out. It involves the material recovery and segregation stage (MRSS), organic extraction (pulping), thermophilic anaerobic digestion (AD), composting, effluent treatment plant (ETP), and biogas genset stages producing: 11.90% recyclables, 33% refused derived fuel (RDF), 5% compost of total waste received, 70 m3/day recyclable water and 0.435 MWh/day electricity. The biogas and methane yield were 0.535 and 0.350 m3/kg VSadded (avg.), respectively, with 40% VS removal (avg total solids (TS) 10%). Less than 3% (inert) of total waste received was subjected to landfill disposal. The MBT plant's revenue generation is 995 US$ per day/148 tons ($ 6.72/ton) waste processed. The gross OPEX is 24 US$/ton making the net OPEX of 17 US$/ton (minus revenue), which could be considered as the excellent OPEX for MSW based MBT plants as per global benchmarks. Further, local usage of RDF can significantly reduce the OPEX to 14 US$/ton, as almost 16% of the OPEX goes towards RDF disposal to cement companies located at a distance of 200–500 km from the MBT plant site. As per LCA study, the total GHG emissions have been calculated to be −25.68 tons CO2 eq./100 tons MSW. The negative emissions result from the export of electricity, compost, and RDF as well as recycling of paper and plastic products. Our study presents a cutting-edge scenario of all-inclusive recycling, recovery, and reuse loop of MSW direly required for accomplishing a circular economy.

Towards a Framework for Sustainable Municipal Solid Waste Management: The Case of Swakopmund Municipality, Namibia

If municipal solid waste (MSW) is not properly managed, harmful environmental consequences are imminent. In many developed countries, MSW materials are hardly discarded but rather retained in the economic cycle through circular economy models. In many developing countries, MSW materials are discarded with little to no effort of repairing or recycling. Moving towards a circular economy substantially reduce waste volumes that are currently being disposed. The study provides an overview of how the current municipal solid waste management strategies being implemented by the Swakopmund Municipality could be shifted towards sustainability to derive environmental and socio-economic benefits from waste. Source reduction, separation at source and recycling, are some of the most effective strategies in the circular economy models that will help achieving the United Nations’ (UN) Sustainable Development Goals (SDGs). Swakopmund Municipality should invest in infrastructure, techniques and programmes that are within circular economy model as an emerging system for sustainability.