Waste Incineration Research Articles

Impact of Municipal Solid Waste Incineration Bottom Ash as Cement Substitution

Impact of Municipal Solid Waste Incineration Bottom Ash as Cement Substitution

Effects of Size and Mechanical Pre-Treatment on Aluminium Recovery from Municipal Solid Waste Incineration Bottom Ash

Municipal solid waste (MSW) is incinerated to reduce the volume and recover energy and materials. The generation of MSW has been increasing over the past few decades due to the increase in population and changing consumption habits. Rising environmental and economic concerns have increased the importance of waste treatment and recovery. Currently, MSW may take three alternate or parallel routes: direct recycling, incineration, or landfill, depending on the country and location. MSW incineration has three products in addition to energy: bottom ash, fly ash, and off-gas. After incineration, bottom ash usually still contains many materials to be recovered, such as glass, ceramics, and metals with a degree of oxidation. This study focuses on aluminium recovery from MSW incineration bottom ash from two different countries. The 2–30 mm fraction of aluminium particles was characterized in terms of its size, shape, and oxide thickness, and its effects on aluminium recovery were investigated. In addition, the ability of mechanical pre-treatment to remove oxides prior to melting was studied. The results were compared with the analytical modeling developed in this study. An increasing particle size and surface area resulted in an increase in aluminium recovery. Mechanical pre-treatment increased the yield for smaller particles to a larger extent than larger particles due to the difference in the oxide/metal ratio.

Legal Framework and Issues in Hazardous Waste Management

Background: Environmental protection is crucial for preventing pollution and maintaining balance. Specific background: Hazardous waste (B3) significantly contributes to pollution, especially when mismanaged. Knowledge gap: Despite existing laws like Law No. 32/2009 on Environmental Protection, enforcement remains a challenge. Aims: This study analyzes B3 waste management under Indonesian regulations and assesses local programs and infrastructure developments. Results: While regulations and programs are in place, such as B3 handling policies and a new waste processing plant, poor compliance hampers effectiveness. Novelty: The study highlights evolving local strategies for improving B3 management. Implications: Stronger enforcement and integrated solutions are key to reducing environmental risks and achieving sustainability. Highlights : Local strategies are evolving to improve B3 waste management. Compliance with environmental regulations remains a significant issue. Technological solutions like waste incineration offer promising improvements. Keywords: Environmental protection, hazardous waste, B3 management, regulatory enforcement, sustainability

ToxPoint: Waste incineration management of plastic materials-an issue of increasing global public health importance.

ToxPoint: Waste incineration management of plastic materials-an issue of increasing global public health importance.

The development of rapid immunoassays for the urinary analysis of 1-hydroxypyrene glucuronide facilitate both laboratory and on-site polycyclic aromatic hydrocarbon biomonitoring

Polycylic Aromatic Hydrocarbons (PAHs) are produced during the incomplete burning of organic materials. PAH sources include vehicle exhaust, tobacco smoke and waste incineration. Environmental and occupational exposures to PAHs are known to occur. Cancer is a significant endpoint of PAH exposure and several occupations associated with high PAH exposure have been classified by IARC as carcinogenic to humans (Group 1).Pyrene is a common component of PAH mixtures and metabolism of pyrene leads to the excretion of 1-hydroxypyrene glucuronide (1-OHPyrG) in urine. Laboratory measurement of urinary 1-OHPyrG is employed in occupational and environmental biomonitoring programmes. The production of an anti-1-OHPyrG monoclonal antibody would allow the development of a PAH biomonitoring ELISA facilitating large scale laboratory screening and routine testing.The development of a lateral flow immunoassay and the production of a field test (point of use test) would greatly increase the value of biomonitoring. A novel Lateral Flow has been developed which employs an anti-1-OHPyrG sheep monoclonal antibody (Mab) to capture the PAH metabolite. The captured metabolite is visualised through a second Mab raised against the Mab-1-OHPyrG immune complex. This sandwich assay provides a positive correlation between the assay signal and biomarker concentration.A Smartphone camera allows signal measurement and a carefully considered ‘app’ provides result interpretation and data analysis. Results are provided in an exposed/not-exposed format. Performance of the lateral flow was confirmed through a comparative study and field trial. The development of a lateral flow test provides "real-time" analysis to occupational health professionals. On-site screening allows the immediate confirmation of safe working practice, provides immediate reassurance to those involved in potentially hazardous activities and greatly increases the efficacy of biomonitoring.

Robust online monitoring system for PCDD/Fs in a full-scale MSWI by Deans switch: Efficiently separation and purification

Existing online monitoring system for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), technically named Thermal Desorption-Gas Chromatography-Tunable Laser Ionization-Time of Flight Mass Spectrometry (TD-GC-TLI-TOFMS), has been applied in several incinerators in China. TD-GC-TLI-TOFMS can realize rapid detection of PCDD/Fs emissions from incineration sources. However, the long-term measurement of unclean flue gas will pollute the instruments in TD-GC-TLI-TOFMS, and interfere with the peak output of the target 1,2,4-trichlorobenzene (1,2,4-TrCBz). In this study, Deans switch (DS) was utilized for the first time in an online monitoring system for PCDD/Fs to separate 1,2,4-TrCBz signal from impurity signals, which improved the anti-interference capability of the system. Laboratory standard gas experiments showed that after adding a DS device between GC and TLI pulse valve, when the pressure set in DS was 4 psi and switched before or near the peak output of 1,2,4-TrCBz, the change of 1,2,4-TrCBz signal intensity was minimal. The impurities near the target peak were removed, and TLI-TOFMS was highly stable during continuous measurement. Moreover, the maximum intensity peak time of 1,2,4-TrCBz was stable after using DS in different switching time intervals. When connecting DS to TD-GC-TLI-TOFMS for field validation on the tail flue gas of a municipal solid waste incinerator (MSWI), results showed that a better 1,2,4-TrCBz signal could be obtained with a 69.52 % reduction of impurity peaks at the moments closer to the target peak. Furthermore, DS improved the sensitivity of the system to low concentration variations of 1,2,4-TrCBz in the flue gas. The robust system developed in this study can be better applied to incineration factories with poor combustion or suboptimal purification technology, facilitating online PCDD/Fs monitoring.

Sulfur-resistant mechanism of MnOx@CeO2@MgO core-shell catalyst in simultaneous removal of NOx and chlorobenzene

Herein, Mn-Ce based catalysts with different structures were rationally designed to explore their sulfur-resistant mechanism for simultaneous removal of NOx and chlorobenzene (CB) from waste incineration at low temperature. In the presence of SO2, MnOx@CeO2@MgO exhibits the highest sulfur resistance among prepared catalysts. Both NOx and CB conversion over MnOx@CeO2@MgO can reach up to 80% at 300 °C. However, the significant deactivation is observed for MnCeMgOx within all temperature ranges. For the selectivity of products, MnOx@CeO2@MgO displays the excellent N2 selectivity (93%) and good CO2 selectivity (80%) at 300 °C. Compared with NO reduction, SO2 has a greater impact on CB destruction due to the consumption of reactive oxygen species during SO2 oxidation. The reduction of active oxygen is proposed to be the reason for the significant inhibition of CB oxidation. The addition of MgO shell increases the proportion of lattice oxygen, which is beneficial to improving the sulfur resistance of MnOx@CeO2@MgO catalyst. In addition, SO2 can react with MgO preferentially to protect the active sites and improve the sulfur resistance. This work indicates that MnOx@CeO2@MgO core-shell catalyst with good sulfur tolerance and stability is expected to be applied in the potential application.

Impact of sulfate to chloride ratio on titanium aluminide coating's high temperature corrosion performance in settings mimicking waste incineration

One major problem with waste incineration is the corrosion of superheater tubes at high temperatures. The presence of sulfate and chloride in this setting poses a severe risk to the boiler's service life. In this work, pack aluminizing was used to create titanium aluminide coating, which was then subjected to five distinct NaCl+Na2SO4 salt combination proportions for 168 h at 600 °C. The outcomes demonstrated that in the presence of solid Na2SO4 deposits, titanium aluminide coating displayed remarkably low corrosion rates. Adding 1/6 NaCl significantly accelerated the rate of corrosion. The electrochemical corrosion resulting from eutectization between NaCl and Na2SO4 was again considerably amplified when the NaCl level was raised to 1/4.

Direct aqueous mineral carbonation of secondary materials for carbon dioxide storage

Mineral carbonation of secondary materials offers an innovative way of storing carbon dioxide in materials that instead would mostly go to waste. This study investigates the carbonation efficiency (CE) of 11 different secondaries from refractory production, waste incineration, and the paper industry compared to untreated and thermally activated serpentinite. To determine the chemical and mineralogical composition of the materials, various analytical methods, like X-ray fluorescence, X-ray diffraction, scanning electron microscopy, Brunauer-Emmet-Teller and thermogravimetric analysis have been employed, both before and after the direct aqueous carbonation process. Each material was examined over reaction times of 6 & 10 hours at 180 °C and a starting pressure of 20 bar in a 0.6 L stainless steel batch reactor. The received results were then compared to the theoretical CO2 uptake, defined as the maximum carbon dioxide storage potential achievable if all Ca, Fe and Mg ions were converted to carbonates. The findings indicate carbonation efficiencies of 14–65 % for secondary materials, compared to 0.7–14 % observed in the serpentinite samples. The highest uptakes were achieved by the refractory materials, primarily due to their high metal oxide content. However, a negative impact was observed from graphite-based carbon binders in the refractories, with increased leaching of these binders leading to a decrease in carbonation efficiency. Materials with higher SiO2 content showed reduced performance, suggesting a passivation layer buildup during carbonation.

Adsorption of dibenzofuran by modified biochar derived from microwave gasification: Impact factors and adsorption mechanism

Dioxins, emanating from the waste incineration, constitutes an organic pollutant that poses considerable risks to the human health and environment. In this study, the corn straw char (CSC) and oak char (OC) derived from the electric heating or microwave gasification, and the coconut-shell activated carbon (AC) are employed as absorbents for the adsorption of dibenzofuran (DBF, dioxins model compound). Characterization techniques, including BET, X-ray CT, SEM-EDS, FTIR, and XPS, are performed to identify the DBF adsorption mechanism on the biochar. The results show that the biochar prepared by the microwave gasification has a more well-developed pore structure than that of the electric heating gasification. The higher porosity (16.94 %) and lower mineral content (1.75 %) are responsible for the effective adsorption of DBF onto AC. The adsorption capacity of CSC is proportional to the modified concentration of KOH. It is mainly ascribed to the decrement of carboxyl and lactone groups and the enhancement of alkaline functional groups on the biochar surface, which augments the hydrophobicity and π–π electron donor–acceptor (EDA) interaction. Instead, DBF adsorption capacity on the biochar is adversely affected by the HNO3 modification. For all biochar samples, the corresponding maximum adsorption ratios are AC (87.11 %) > KOH-modified CSC (77.14 %) > unmodified CSC (49.11 %) > unmodified OC (39.70 %) > HNO3-modified CSC (36.09 %). The adsorption mechanisms of DBF on the gasified biochar encompass the pore filling, hydrophobicity, and π–π EDA interaction. A desirable adsorption capacity of DBF on the biochar prepared by the microwave gasification is attainable through augmenting the specific surface area while diminishing the oxygen-containing groups of the surface simultaneously.

Carbon footprint impact of waste sorting on the municipal household waste treatment system: A community case study of Hangzhou

Considering the pressing need to reduce carbon emissions, the environmental impacts of waste sorting and its influencing factors remain unverified across many practical scenarios. This study focused on separating perishable and residual waste in a community in Hangzhou, China, examining how waste sorting behavior affects the carbon footprint of subsequent waste treatment systems through a randomized tracking survey and life cycle assessment (LCA) method. The results indicated that the sorted waste treatment system could achieve net carbon emissions ranging from −139.92 to −254.03 kg CO2 eq per day by integrating the anaerobic digestion of sorted perishable waste with the incineration of residual waste. In comparison to the conventional mixed incineration system, which had net carbon emissions between −56.37 and −115.46 kg CO2 eq per day and generated 383 kWh/t of power, the carbon reduction benefits of the sorted system were considerably greater, by a factor of 2.2–2.5. Additionally, the average amount of recovered electrical energy (993 kWh/t) was also higher by a factor of 2.6. Therefore, source separation of waste significantly enhances energy recovery and carbon reduction in household waste treatment systems. In this research system, incineration power generation and oil recovery serve as the primary units for reducing carbon emissions, and the proportion of residual waste generated greatly influences the total carbon emissions of the sorted waste treatment system (p < 0.05). Consequently, increasing the percentage of classified residual waste and optimizing machine efficiency will increase the carbon reduction benefits of waste sorting and treatment systems. These findings provide crucial references and guidance for advancing carbon reduction and waste classification in municipal solid waste (MSW) management systems.

Safety assessment of introducing radioactive waste incineration facilities in Korea: An off-site resident dose evaluation

As nuclear power technology advances, radioactive waste accumulation rises, necessitating measures to alleviate strain on disposal facilities and minimize waste management costs. Analysis of radioactive waste composition revealed that combustible waste comprised the largest proportion (45 %), with incineration demonstrating high reduction efficiency for this fraction. In order for a radioactive waste incineration facility to be introduced, it is necessary to evaluate the safety of gas radioactive effluent generated during city operation. Evaluation criteria have already been established and methodologies also exist, but these results greatly depend on the area where the incineration facilities are located, the waste to be treated, the operation method of the facilities. Accordingly, this study assumed annual throughput and radionuclide concentrations based on the radioactive waste stored and generated in Korea. The centralized operation method at a specific site was compared with the decentralized operation method employed at all sites. Post-incineration, the impact of radionuclides released from the facilities was analyzed against Nuclear Safety and Security Commission standards, confirming the discharge standards and doses for single facilities and entire sites.

Optimization of Sustainable Alkali Activated Municipal Solid Waste Incinerator Bottom Ash Materials with High Performance

Optimization of Sustainable Alkali Activated Municipal Solid Waste Incinerator Bottom Ash Materials with High Performance

Analysis of the Influence of Variation in Medical Waste Heating Value on the Electrical Energy Output of Generator in Medical Waste Cogeneration Incinerator System using Gatecycle Solver

Abstract Medical waste incinerator is a technology capable of processing and exterminating hazardous medical waste through combustion at temperatures exceeding 800°C. Medical waste exhibits a range of heating values depending on its material composition. The heating value represents the potential heat energy released when a substance undergoes complete combustion. A cogeneration incinerator is designed to treat medical waste while also harnessing the heat of the flue gas that emanates from the combustion process. The flue gas acts as a hot fluid that transfers its heat, causing the water temperature inside the boiler to increase and transform into high-temperature steam. This steam drives a steam turbine connected to a generator to generate electrical energy. The amount of electrical energy generated is influenced by the steam quality produced through the boiler’s water-heating process. This study aims to investigate the influence of variation in the heating value in medical waste on the electrical energy output of the generator in a medical waste cogeneration incinerator system. The range of heating value variations used in the testing varies from 25 MJ/kg to 35 MJ/kg. The variation is tested through thorough simulations using GateCycle software to obtain data on the electrical energy generated. To achieve a maximum electrical energy output of 200 kW, fuel with a total heating value of 32.25 MJ/kg is required. This study is beneficial to be implemented as renewable energy sources based on biomass powerplant systems.

Corrosion performance of (ZrYTaAlCr)O ceramic coating materials for heated surface tubes

The comprehensive advantages of waste incineration power generation are evident, gradually replacing composting, landfill, and other treatment methods. However, the presence of chlorine, sulfur, heavy metals, and a variety of hazardous elements in the flue gas has led to severe corrosion of the heated surface tubes of the waste incineration boilers and an increase in the failure rate of the boilers, thus restricting the wider application of waste incineration power generation technology. In this study, (ZrYTaAlCr)O high-entropy ceramic materials were synthesized via the solid-phase reaction method and subjected to exposure in a standard corrosive mixture (SCM) simulating the molten salts environment of waste incineration boilers, consisting of NaCl (25 mol%), KCl (25 mol%), Na2SO4 (25 mol%), and K2SO4 (25 mol%). The corrosion behavior of (ZrYTaAlCr)O ceramics with different proportions was studied through visual detection, corrosion kinetics, XRD, and SEM/EDS analysis. The results show that (Zr0.5Y0.125Ta0.125Al0.125Cr0.125)O forms a NaTaO3 tantalate protective layer in the early stages of corrosion, with fewer types of corrosion products. Compared with other compositions, (Zr0.5Y0.125Ta0.125Al0.125Cr0.125)O has good corrosion resistance and is suitable as a corrosion protection material for the heating surface tubes of waste incineration boilers.

Synergistic effect of rhamnolipid and Bacillus mucilaginosus on detoxification and activation of municipal solid waste incineration fly ash

In recent years, the substantial increase in municipal solid waste incineration fly ash (MSWIFA) production has made its treatment a critical issue. However, the high toxicity of MSWIFA makes its utilization still in the exploratory stage. In this study, the heavy metal leaching rate, particle size distribution and activity index of MSWIFA were tested to investigate the detoxification and activation effects of Bacillus mucilaginosus on MSWIFA by introducing rhamnolipid. The results show that the microbial treatment can greatly increase the leaching rate of heavy metals in MSWIFA and its 28-day and 90-day activity indexes, especially by the synergistic treatment. For the Bacillus mucilaginosus and rhamnolipid treated MSWIFA (BR-MSWIFA), the maximum leaching rates follow the order from high to low of 85.57% Cr, 78% Cu, 76.38% Zn, 62.78% Pb and 37.65% Mn, while having a low mass loss of less than 5%, which is important for its reuse. Moreover, compared with the untreated MSWIFA (U-MSWIFA), the average particle sizes of Bacillus mucilaginosus treated MSWIFA (B-MSWIFA) and BR-MSWIFA decrease from 8.39 μm to 7.80 μm and 4.31 μm, and the 28-day activity indexes increase from 80.19% to 101.59% and 110.61%. The effect mechanism is that rhamnolipid not only can promote the growth, reproduction, and metabolic acid production of Bacillus mucilaginosus, but also disperse the extracellular polymeric substance (EPS) and MSWIFA particles, thus increase their contact area and the bioleaching. This study provided a theoretical foundation for the harmless treatment and resource utilization of solid wastes containing heavy metals.

Nanosilica-enhanced geopolymer cementitious materials: Mechanistic insights from experimental and computational simulations

To mitigate the pollution associated with municipal solid waste incineration fly ash (MSW-IFA), solidification/stabilization (S/S) techniques have garnered considerable attention. This study systematically investigates the modification effects of nanosilica (NS) on the properties of geopolymer functional cementitious materials (GFCM) derived from waste fly ash. By integrating experimental data with simulation-based calculations, the influence of NS on the macroscopic properties and microstructure of GFCM, including mechanical performance, heavy metal immobilization mechanisms, and hydration processes, was examined. The results indicate that NS enhances mineral phase and pore structure through pozzolanic and filling effects, promoting additional C-S-H gel formation and pore filling, which significantly accelerates the hydration process and improves mechanical properties. Furthermore, NS increases the proportion of heavy metals in a stable state, thereby reducing their leaching potential. Density functional theory (DFT) calculations further revealed that NS's modification effects primarily occur via filling, nucleation, and pozzolanic activity, which supported the construction of a geopolymer reaction network. This study offers a validated approach for advancing the understanding of NS modification mechanisms, the development of geopolymer reaction networks, and the mechanisms governing heavy metal S/S.

A novel use of incineration bottom ash for H2 aeration in the production of artificial lightweight aggregates

Cold bonding is an energy-efficient method for producing artificial aggregate (AA). However, the relatively high density of AA restricts its use in lightweight concrete products. This study aims to fully upcycle aluminum (Al) content in municipal solid waste incineration bottom ash (IBA) for H2 aeration in the production of lightweight artificial aggregate through alkali activation. To achieve this, the glass particles (GP) in IBA were ground into powder and used as the precursor for NaOH, while the remaining IBA (RIBA), rich in Al, served as the foaming agent. The results showed that RIBA particles (<300 μm) can be used to produce lightweight AA with a loose bulk density ranging from 780 to 840 kg/m3, comparable to sintered fly ash aggregates, and a wide pore size distribution ranging from 0.02 mm to over 1 mm. The inclusion of finer RIBA particles (<75 μm) enhanced the homogeneity of the pore structure, resulting in aggregate strengths of 0.4–0.6 MPa. Moreover, increasing the GP content in IBA up to 40% further boosted the aggregate strength to 1.1 MPa by refining the pore structure and promoting more (C)-N-A-S-H gels with Q4 structures. To ensure sufficient geopolymerization reactions and achieve high strength in the AAs, the alkali concentration should be kept above 3 mol/L. The proposed strategy for lightweight AA production reduced the global warming potential by about 20% compared to the conventional sintered method, offering a more environmentally friendly approach.

Assessment of mechanical and heavy metal leaching behavior of engineered cementitious composites incorporating ultra-high-volume municipal waste incineration bottom ash

This study aimed to explore the feasibility of incorporating 100% municipal solid waste incineration bottom ash (MSWIBA) as a replacement for fine aggregates in engineered cementitious composites (ECCs). To improve mechanical properties, three types of polymer fibers (PVA, PP, and PE) were used at dosages of 0-2% by volume. The impact of fiber content on compressive strength, elastic modulus, and other key performance indicators such as peak strain, ultimate strain, damage modulus, and toughness index was systematically investigated. Results showed that while the elastic modulus and peak stress slightly decreased with increasing fiber content due to fiber agglomeration and increased macro-porosity, fibers significantly enhanced the deformation capacity and toughness. For instance, the MSWIBA-ECCs with 2% PP fibers exhibited the highest compressive damage energy of 205.47 J, a 79.48% increase over the control group, demonstrating superior toughness. Additionally, the study developed a new constitutive model that accurately predicted stress-strain behavior considering fiber characteristics. Environmental assessment revealed that MSWIBA-ECCs effectively immobilized hazardous heavy metals (Cu, Ni, Pb, Zn), with a solidification efficiency of 97%, ensuring compliance with Chinese environmental standards. These findings suggest that MSWIBA-ECCs, combined with optimized fiber content, offer a sustainable and high-performance alternative for construction applications.

Studies on Alkaline Activator, Manufacturing Methods and Mechanical Properties of Geopolymer Concrete - A Review

Continuous production of cement products, a new environmentally responsible geopolymer material, can reduce CO2 emissions from increased cement production. Compared to ordinary Portland cement (O.P.C.) geopolymer concrete, it has better mechanical strength and corrosion and fire resistance. Most industrial solid wastes and bottom ash from waste incineration are disposed of unevenly, which consumes land resources and negatively affects the ecosystem. The best alternative resource for the synthesis of geopolymer composites is recycling. Metals, pesticides, and other radioactive pollutants are successfully absorbed by geopolymer composites, which is very favorable for the ultimate development of civilization. Therefore, this review has examined essential material parameters, including new properties, compressive strength, flexural strength, elastic Modulus, compressive strength, and split-tensile strength applications. According to the previous experimental results, G.P.C. offered better fresh properties than conventional composites. This review revealed the geopolymerization process, the types of alkaline/alkali activators, synthesis techniques, sources of natural raw materials, and applications of geopolymer concrete. The present work discussed the conceptual framework for the sustainable production of geopolymer materials by evaluating the drawbacks, applications, and restrictions of geopolymer materials and their potential development.