Municipal Incineration Research Articles

Blending electric arc furnace slag and municipal incineration bottom ash to make ceramic tiles

Blending electric arc furnace slag and municipal incineration bottom ash to make ceramic tiles

4E analysis of a municipal incinerator power plant with an ORC and optimization

4E analysis of a municipal incinerator power plant with an ORC and optimization

Structure and phase composition of ceramics based on pre-treated municipal incinerator bottom ash

In recent decades it has been demonstrated that some of the traditional raw materials in the ceramics industry could be successfully replaced by various industrial wastes. Sometimes, when the chemical composition of the waste is suitable, it is even possible to simply mix the waste with clay materials and to obtain new ceramics without feldspars, with higher crystallinity and improved mechanical properties. However, the sintering process and structure of these materials are very different from those of traditional clay-silica-feldspar ceramics. This is probably one of the reasons why they are not yet recognised as a viable alternative.The aim of this work is to investigate and explain the differences in phase composition and structure of six ceramics, based on bottom ashes from municipal incinerators, which form different amounts of amorphous phase, anorthite and pyroxene. For a better understanding, the viscosities of the residual melts at the corresponding sintering temperatures are also evaluated.It is shown that in the compositions richer in silica, the sintering temperatures are lower and the viscosity is significantly higher. As a result, notwithstanding of the high amount of formed glassy phase, the sintering is incomplete.At the same time, in the ceramics enriched with CaO and Al2O3, which form 40–45 wt% crystalline phase, the sintering temperatures are higher, but the viscosity is lower and the water adsorption is near zero. It is also clarified that in these compositions partial phase formation occurs on cooling, which increases their closed porosity.

Implementation of electrocoagulation for reduction of Zn in an outlet stream from waste incineration plant

The paper is focusing on the full-scale operation of electrocoagulation for Zn removal from wastewater with origin in a municipal incineration plant. The process was custom designed for continuous full-scale operation. Total capacity of the process varied between 1200 and 1400L/h. This was achieved by two simultaneous electrocoagulation cells operated in parallel. Residual concentrations of Zn in the treated water were consistently lower than 0.5 mg/L during the testing period. Residual concentrations of Zn and other accompanying contaminants were reduced below the desired limits (current limit for Zn in outlet water is 1.5 mg/L). The process cost was critically assessed. The electricity consumption for the operation of electrocoagulation cells is 0.75–1.1 kWh/m3 of purified water. A more significant expense is the consumption of electrode cartridges. The service life of electrode cartridges with a plate thickness of 5 mm is about 1 200 m3 of water/electrode pack, which represents a cost of around 0.6–1 EUR/m3 out of total 1.6 EUR/m3 of purified water. Waste incineration plants usually produce their own electricity therefore technologies like electrocoagulation become affordable and competitive.

Distribution characteristics and ecological risks of heavy metals in bottom ash, fly ash, and particulate matter released from municipal solid waste incinerators in northern Vietnam.

Residue concentrations of heavy metals, including As, Cd, Cr, Cu, Ni, Pb, and Zn, were determined in bottom ash, fly ash, and particulate matter (PM10) samples collected from five municipal incinerators in northern Vietnam to assess their occurrence, distribution characteristics, and potential risks. Concentrations and profiles of heavy metals are presented, showing the dominance of Zn in all types of samples. Highly volatile elements (Cd, Pb, and Zn) were found at elevated proportions in PM10 but not fly ash. The large difference in the heavy metal profiles could be explained by the variation of input raw materials, the absence of an appropriate cycle for the material feeding process, and post-combustion technology applied. Mass balance of heavy metals in the bottom ash, fly ash, and PM10 varied significantly between the investigated incinerators, largely due to the difference in incineration technology and air pollution control system. Emission factors and annual emissions were also estimated, indicating the highest value and amount in bottom ash, followed by PM10 and fly ash. Our results are among the first studies reporting contents and emissions of toxic elements in incinerated solid wastes in Vietnam.

Analysis of Ambient Air PM10-Bound Pollutants Surrounding an Industrial Site and Their Prediction Using Artificial Neural Network

The 2030 Agenda dictated the Sustainable Development Goals. It states the waste reduction needs through their reuse, i.e., considering them as secondary raw materials (Objective 12.5). Bottom ashes from municipal or industrial incinerators can be reused as partial cement replacement in concrete after preventive physical processes such as ferrous metals removal (magnetic separation) and nonferrous metals removal (Eddy current separation). Net of the principal pollutant containment systems, diffusive emissions of fine particles from these processes, coupled with several screening steps and a final long-time open-air residues stabilization, could impact the surrounding environment due to the chemical composition of the particulate matter itself (inorganic and organic pollutants). Moreover, the particulate may also arise from transporting the raw bottom ashes to the pre-treatment plant (point source). The present work aims to predict the concentration of the PM10-bound organic contaminants that are usually sampled weekly (PCDD/Fs, PCBs, PAHs) from the concentration of the daily analyzed inorganic pollutants in the surrounding area of an municipal solid waste slag treatment plant, using Artificial Neural Networks (ANNs) as a forecasting tool. Moreover, ANNs have also been used as a clustering tool to evaluate the plant’s environmental impact on the surrounding area with respect to other additional emission sources.

Evaluation of Extinction Effect of PM2.5 and Its Chemical Components during Heating Period in an Urban Area in Beijing–Tianjin–Hebei Region

PM2.5 pollution and visibility impairment has attracted wild public attention in urban China during the past decade. Field observation was carried out in Tianjin, China, during heating (HP) and non-heating periods (NHP). The IMPROVE (Interagency Monitoring of Protected Visual Environments) method was localized to better understand the quantitative impact of PM2.5 composition on extinction coefficient (Bext). Bext of organic mass (OM) was classified into that of primary organic aerosol (POA) and secondary organic aerosol (SOA). Bext of Rayleigh scattering was calculated based on observation data directly, instead of a fixed value in the original IMPROVE method. The mass extinction efficiency (MEE) of EC was also updated based on literature research. The estimation bias of reconstructed Bext was reduced from 4.8 Mm−1 to 0.8 Mm−1 with the localized algorithm. It was found that the secondary components contribute more than 40% of Bext, and ammonium sulfate (AS) and ammonium nitrate (AN) are the dominant components. The different formation pathway leads to significant difference in secondary inorganic components during HP and NHP. Based on the positive matrix factorization (PMF) model and localized IMPROVE method, secondary aerosols were identified as the main source contributing to both PM2.5 concentration (48.2%) and Bext (44.3%) during HP, followed by vehicular emission and coal combustion, biomass burning with municipal incinerators, fugitive dust, and steel processing.

Characterizing spatiotemporal variability in airborne heavy metal concentration: Changes after 18 Years in Baltimore, MD

IntroductionThis study investigates the impact of changes in local industry, urban development, and proximity to suspected emission sources on airborne metal concentration in Baltimore, Maryland between 2001 and 2019 with particular focus on the urban industrial community of Curtis Bay in South Baltimore. MethodsIntegrated PM2.5 and PM10 Harvard Impactors were set up at six locations in the Baltimore City metropolitan area in weeklong sampling sessions from January–July 2019 to assess variation in airborne metal concentration by proximity to suspected metal emission sources. PM2.5 and PM10 were collected on Teflo filters and analyzed for a panel of 12 metals and metalloids (As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, and Zn) using inductively coupled plasma mass spectrometry. The findings were compared against airborne metal concentrations reported by the Baltimore Supersite in 2001 and 2003 to assess changes over the 18-year period. ResultsPM2.5 concentrations reported from this study ranged from 3.27 μg/m3 to 36.0 μg/m3 and PM10 concentrations ranged from 9.00 μg/m3 to 30.1 μg/m3 across all sampling sites. Metal concentrations ranged from 1.4 times (Cd) to 4.8 times (Cr) higher in PM10 compared to PM2.5. Compared to the study reference site, median PM2.5 concentrations of Co and Fe were roughly 1.8 times and 2.1 times higher, respectively, at near-road sampling sites indicating significant variability in airborne metal concentration by proximity to local traffic emissions. PM2.5 and PM10 Sb concentrations were 3.4 times and 6.7 times higher at a near incinerator site compared to the reference, consistent with existing evidence of Sb sourcing from municipal incinerators in Baltimore City. Decreases in Cr (−40%), Ni (−73%), Pb (−55%), and Zn (−36%) concentrations were observed over the 18-year period while concentrations of Cu, Fe, and Mn were not statistically significantly different. ConclusionDeclines in airborne Cr, Ni, Pb, and Zn concentration since 2001 appear to coincide with industrial decline highlighting the success of remediation and redevelopment efforts. Remaining spatial variability is related to vehicular traffic and proximity to a municipal incinerator which should be focal areas for future intervention to reduce metal exposure disparities in Baltimore City.

Study of the operative conditions and the optimum amount of municipal incinerator bottom ash for the obtainment of ceramic floor tiles.

The idea of reusing municipal incinerator bottom ash (MIBA), the residue from incinerating municipal solid wastes, fits nicely in a circular economy scheme, which leads to an avoided impact of landfill disposal, and at the same time reduces the demand of natural resources. Past studies have attempted to add 20 to 60% MIBA for ceramic production, and resulted in some inspiring success. Focused on delivering quality interior and exterior floor tiles meeting industrial standards, this study investigated the operative conditions and the optimum amount of MIBA in the mix. In this study, only the kaolinite clay and MIBA were used. Before making specimens, raw materials of clay and MIBA underwent SEM, EDS, and TCLP tests to determine their chemical contents. Six sets of specimens with different replacement levels of MIBA (0%, 5%, 10%, 15%, 20%, and 30%) were then prepared. These specimens were fired at 1000°C, 1050°C,1100°C, and 1150°C and the products underwent a series of mechanical tests to verify their performance. NMR (nuclear magnetic resonance spectroscopy) were also used to determining the organic compound structure after each specimens' crystallization. Research results showed that proper mix of MIBA up to 20% could result in quality tiles complying with specifications for interior and exterior flooring applications at certain kiln temperatures, while the specimens with 30% MIBA failed to meet either bending strength or size shrinkage requirement at all four kiln temperatures, and could not deliver a satisfactory result.

Assessment of Biological Degradability of the Waste Produced by Food Industry

Abstract Organic waste from production processes is unutilised potential for the production of energy from renewable sources. The submitted paper studies the conditions of anaerobic degradation of selected waste from food industry (diary and distillery) when biogas is produced. Both types of organic waste have low pH values. Ash form municipal incineration as a material for the treatment of pH of waste was used. Except for the pH increase during anaerobic degradation, ash also serves as a source of macroelements for inoculum microorganisms. Kinetics of anaerobic biological digestion of organic material based on the change of pressure and biogas production depending on the ash addition (change of pH) of input samples was observed. Beside these tests, degradability of the waste was assessed by limiting biologically degradable ratio, BR and specific speed of degradability, q. pH values were adjusted with different amounts of ash (0.5; 1.8; 2.7 g/g of dry matter of organic material). Results of the research confirmed that the addition of optimum amount of ash has a positive effect on anaerobic degradation of organic materials.

Applying Mixture of Municipal Incinerator Bottom Ash and Sewage Sludge Ash for Ceramic Tile Manufacturing.

Municipal incinerator bottom ash (MIBA) and sewage sludge ash (SSA) are secondary wastes produced from municipal incinerators. Landfills, disposal at sea, and agricultural use have been the major outlets for these secondary wastes. As global emphasis on sustainability arises, many have called for an increasing reuse of waste materials as valuable resources. In this study, MIBA and SSA were mixed with clay for ceramic tile manufacturing in this study. Raw materials firstly went through TCLP (Toxicity Characteristic Leaching Procedure) to ensure their feasibility for reuse. From scanning electron microscopy (SEM), clay’s smooth surface was contrasted with the porous surface of MIBA and SSA, which led to a higher water requirement for the mixing. Specimens with five MIBA mix percentages of 0%, 5%, 10%, 15%, and 20% (wt) and three SSA mix percentages of 0%, 10%, and 20% (wt) were made to compare how the two waste materials affected the quality of the final product and to what extent. Shrinkage tests showed that MIBA and SSA contributed oppositely to tile shrinkage, as more MIBA reduced tile shrinkage, while more SSA encouraged tile shrinkage. However, as the kiln temperature reached 1150 °C, the SiO2-rich SSA adversely reduced the shrinkage due to the glass phase that formed to expand the tile instead. Both MIBA and SSA increased water tile absorption and reduced its bending strength and wear resistance. Increasing the kiln temperature could effectively improve the water absorption, bending strength, and wear resistance of high MIBA and SSA mixes, as SEM showed a more compact structure at higher temperatures. However, when the temperature reached 1100 °C, more pores appeared and seemingly exhausted the benefit brought by the higher temperature. Complex interactions between kiln temperature and MIBA/SSA mix percentage bring unpredictable performance of tile shrinkage, bending strength, and water absorption, which makes it very challenging to create a sample meeting all the specification requirements. We conclude that a mix with up to 20% of SSA and 5% of MIBA could result in quality tiles meeting the requirements for interior or exterior flooring applications when the kiln temperature is carefully controlled.

Life cycle assessment of heavy metal contaminated sites: phytoremediation and soil excavation

Phytoextraction by native Taiwanese chenopod (Chenopodium formosanum Koidz.) and Napier grass (Pennisetum purpureum) for heavy metals such as chromium (Cr), nickel (Ni), and copper (Cu) was reported first. Maximum bioconcentration factors of Cu and Cr were 8.8 and 12.5 by Taiwanese chenopod. Napier grass cultivar Taishi No.4 plants demonstrated higher survivals than that of Taiwanese chenopod, under heavy metal stress in soils. All heavy metal accumulation and biomass data were employed, as well as historical engineering data were collected for conventional excavation-and-refill remediation of two sites. Life cycle assessment (LCA) was conducted for comparing environmental performances of phytoextraction and conventional remediation for two contaminated sites. Assuming one-year growth, three harvests were done and biomass was collected and sent to the nearest municipal incinerators, phytoextraction by both plants demonstrated superior environmental performances than conventional methods for contaminated site remediation. High quantities of fuels to haul the soils of conventional methods mainly contributed to the greenhouse gas emission. Phytoextraction has the most advantages for sites with lesser extents of pollution and time restraints. Environmental performances of phytoremediation were even better if energy recovered from biomass incineration is counted. Novelty statement Phytoextraction by native Taiwanese chenopod and Napier grass was firstly reported. Life cycle assessment was conducted for comparing the phytoextraction and conventional remediation. Phytoextraction demonstrated superior environmental performances. Energy reutilization of biomass recovered made phytoremediation more sustainable.

Sintering and phase formation of ceramics based on pre-treated municipal incinerator bottom ash

Ceramics, based on 60 ​wt% of municipal incinerator bottom ashes (MIBA) and 40 ​wt% of industrial clays, were prepared by using two fractions of pre-treated ashes (above and under 2 ​mm) and three different industrial clays. The obtained six compositions with amounts of CaO from 12 to 14 ​wt%, with SiO2/Al2O3 ratio ranging from 3.5 to 1.6 and with Al2O3/CaO ratio - from 1.25 to 1.75 were investigated and characterized.These compositions were located in the crystallization field of anorthite (CaO.Al2O3.2SiO2); the ceramics with high SiO2/Al2O3 ratio are near to the eutectic with SiO2, while with low ratio – closer to the anorthite stoichiometry.The phase transformation and the subsequent melting were studied by non-isothermal DTA-TG analysis, while the densification process - by contactless optical dilatometry. Then, the optimal sintering temperatures and times were evaluated by isothermal dilatometric runs at different temperatures.At high SiO2/Al2O3 ratio the sintering temperature is lower but the sintering range is very narrow. This behavior can be explained by the formation of too high amount of liquid phase at the eutectic temperature. On the contrary, at lower ratio, the sintering temperature increases but, notwithstanding the decrease of viscosity and shorter sintering time, the densification range becomes wider. This last result is a very important technological finding with a view to industrial transferability.Additional tests performed demonstrated that a preliminary thermal treatment of ash with elevated residual organic phase is necessary, which leads to a lower firing shrinkage and to a shorter sintering time.

Changes in source contributions to particle number concentrations after the COVID-19 outbreak: Insights from a dispersion normalized PMF

Factor analysis models use the covariance of measured variables to identify and apportion sources. These models, particularly positive matrix factorization (PMF), have been extensively used for analyzing particle number concentrations (PNCs) datasets. However, the variation of observed PNCs and particle size distribution are driven by both the source emission rates and atmospheric dispersion as well as chemical and physical transformation processes. This variation in the observation data caused by meteorologically induced dilution reduces the ability to obtain accurate source apportionment results. To reduce the influence of dilution on quantitative source estimates, a methodology for improving the accuracy of source apportionment results by incorporating a measure of dispersion, the ventilation coefficient, into the PMF analysis (called dispersion normalized PMF, DN-PMF) was applied to a PNC dataset measured from a field campaign that includes the Spring Festival event and the start of the COVID-19 lockdown in Tianjin, China. The data also included gaseous pollutants and hourly PM2.5 compositional data. Eight factors were resolved and interpreted as municipal incinerator, traffic nucleation, secondary inorganic aerosol (SIA), traffic emissions, photonucleation, coal combustion, residential heating and festival emissions. The DN-PMF enhanced the diel patterns of photonucleation and the two traffic factors by enlarging the differences between daytime peak values and nighttime concentrations. The municipal incinerator plant, traffic emissions, and coal combustion have cleaner and more clearly defined directionalities after dispersion normalization. Thus, dispersion normalized PMF is capable of enhancing the source emission patterns. After the COVID-19 lockdown began, PNC of traffic nucleation and traffic emissions decreased by 41% and 44%, respectively, while photonucleation produced more particles likely due to the reduction in the condensation sink. The significant changes in source emissions indicate a substantially reduced traffic volume after the implement of lockdown measures.

Characterization and Source Identification of Elements and Water-Soluble Ions in Submicrometre Aerosols in Brno and Šlapanice (Czech Republic)

Submicrometre aerosol particles (particulate matter, PM1) were collected in two Czech cities (Brno and Šlapanice) during week campaigns in winter and summer of 2009 and 2010. The aerosols were analysed for 14 elements and 12 water-soluble ions using inductively coupled plasma–mass spectrometry and ion chromatography techniques. The average PM1 mass concentration was 14.4 and 20.4 µg m−3 in Brno and Šlapanice, respectively. Most of the analysed elements and ions exhibit distinct seasonal variability with higher concentrations in winter in comparison to summer. The determined elements and ions together accounted for about 29% of total PM1 mass, ranging between 16% and 44%. Ion species were the most abundant components in collected aerosols, accounting for 27.2% of mass of PM1 aerosols, and elements accounted for 1.8% of mass of PM1 aerosols. One-day backward trajectories were calculated using the Hysplit model to analyse air masses transported towards the sampling sites. The Pearson correlation coefficients between individual PM1 components and PM1 mass and air temperature were calculated. To identify the main aerosol sources, factor analysis was applied. Six factors were identified for each locality. The following sources of PM1 particles were identified in Brno: a municipal incinerator, vehicle exhausts, secondary sulphate, a cement factory, industry and biomass burning. The identified sources in Šlapanice were as follows: a combustion source, coal combustion, a cement factory, a municipal incinerator, vehicle exhausts and industry.

Bioleaching for resource recovery from low-grade wastes like fly and bottom ashes from municipal incinerators: A SWOT analysis.

Bioleaching (or microbial leaching) is a biohydrometallurgical technology that can be applied for metal recovery from anthropogenic waste streams. In particular, fly ashes and bottom ashes of municipal solid waste incineration (MSWI) can be used as a target material for biomining. Globally, approximately 46 million tonnes of MSWI ashes are produced annually. Currently landfilled or used as aggregate, these contain large amounts of marketable metals, equivalent to low-grade ores. There is opportunity to recover critical materials as the circular economy demands, using mesophile, moderately thermophile, and extremophile microorganisms for bioleaching. A Strengths, Weaknesses, Opportunities and Threats (SWOT) analysis was developed to assess the potential of this biotechnology to recover critical metals from MSWI wastes. Bioleaching has potential as a sustainable technology for resource recovery and enhanced waste management. However, stakeholders can only reap the full benefits of bioleaching by addressing both the technical engineering challenges and regulatory requirements needed to realise and integrated approach to resource use.

Utilization of innovative system for coke oven wastewater treatment as an element of stabilization technology for post-process waste from municipal incineration plants

The article discuss the possibility of using the system for coke oven wastewater treatment process that has been developed within the framework of the project: The innovative system for coke oven wastewater treatment and water recovery with the use of clean technologies — INNOWATREAT that has received funding from the Research Fund for Coal and Steel under Grant Agreement No. 710078 and from the Ministry of Science and Higher Education Poland from financial resources on science in 2016-2019, for the removing the hazardous elements and compounds from wastewater from leaching ashes from municipal waste incineration plants. The results achieved in the project are compared with analysis provided for two different sources of ash from Poland and one Lithuania. The article discuss predicted effectiveness of the method and possibility their use in wider method of post-process waste stabilization technology as well as potential risk connected with implementation this solution into practice.

Leaching Characteristics of Radiocesium in Municipal Incineration Ash and Safety Measures Utilizing Clay Minerals

Leaching Characteristics of Radiocesium in Municipal Incineration Ash and Safety Measures Utilizing Clay Minerals

Waste incineration of Polytetrafluoroethylene (PTFE) to evaluate potential formation of per- and Poly-Fluorinated Alkyl Substances (PFAS) in flue gas

In recent years, concerns over some per- and polyfluorinated alkyl substances (PFAS) have grown steadily. PFAS are a large group of chemical substances with widely differing properties. While one class of PFAS, fluoropolymers, have been demonstrated to meet the OECD criteria for polymers of low concern during the in use phase of their lifecycle, questions remain regarding waste handling at the end of useful life for products containing fluoropolymers. To show that polytetrafluoroethylene (PTFE) can be almost fully transformed into fluorine (F) (as hydrofluoric acid (HF)) and to study the possible generation of low molecular weight per- and polyfluorinated alkyl substances (PFAS), PTFE combustion under typical waste incineration conditions at the BRENDA (German acronym for “Brennkammer mit Dampfkessel”) pilot plant at Karlsruhe Institute of Technology (KIT) was investigated. Results indicate that, within procedural quantitation limits, no statistically significant evidence was found that the PFAS studied were created during the incineration of PTFE. Therefore, municipal incineration of PTFE using best available technologies (BAT) is not a significant source of the studied PFAS and should be considered an acceptable form of waste treatment.

Reuse of bottom ash and fly ash from mechanical-bed and fluidized-bed municipal incinerators in manufacturing lightweight aggregates

This study involved the reuse of residues, including fly ash (FA) and bottom ash (BA), from municipal solid waste (MSW) incineration and reservoir sediment (RS) to make lightweight aggregates (LWAs) and to evaluate the effects of the incinerator type, material mixing ratio, and preparation conditions on the properties of the resulting aggregates. The MSW incineration ashes were mixed in three different ratios (65% BA + 15% FA, 70% BA + 10% FA, and 75% BA + 5% FA) with reservoir sediment and were sintered at temperatures of 950–1050 °C. The ash samples were obtained from an incineration plant equipped with fluidized-bed (FB) and mechanical-bed (MB) furnaces. The ash from the FB incinerator could be turned into LWAs at a relatively low temperature (1000 °C). Compressive strength measurements indicated that these aggregates were stronger than those manufactured using the ash from the MB incinerator. The BA and FA from the FB incinerator showed good chemical stabilities due to the operating conditions of the incinerator, suggesting that they are suitable for fabricating LWAs. Thus, the thermal synthesis of LWAs from mixtures of incineration residue and RS is a highly effective method for the recycling/disposal of MSW incinerator ash.