Ash Waste Research Articles

Preparation of autoclaved-aerated concrete with waste ash of petroleum coke gasification

ABSTRACT In this paper, a novel route for the utilisation of petroleum coke gasification ash in the preparation of autoclaved-aerated concrete (AAC) is presented. The waste ash along with quartz sand, cement, lime, and gypsum are used as the primary raw materials, with aluminium powder paste serving as the pore-forming agent. The effect of incorporating petroleum coke gasification ash on the dry density and thermal conductivity of the resulting AAC was investigated. The results indicate that the thermal insulation performance of AAC is significantly enhanced by reducing the thermal conductivity coefficient upon the addition of treated petroleum coke gasification ash. At a 40% ash content, the AAC exhibits remarkable performance that meet the requirements of A2.5B05 in GB 11,968-2006, with compressive strength higher than 2.5 MPa and dry density lower than 525 kg m−3. Furthermore, the study examined the optimal calcium silicon ratio after the addition of the ash, with the results demonstrating that AAC prepared with a ratio of 0.25–0.26 exhibits the best compressive strength and dry density. The present study offers a novel perspective on waste management, which carries substantial significance for both the environmental and construction industries.

Innovative machine learning approaches to predict the compressive strength of recycled plastic aggregate self-compacting concrete incorporating different waste ashes

Innovative machine learning approaches to predict the compressive strength of recycled plastic aggregate self-compacting concrete incorporating different waste ashes

Increase in Recovery Efficiency of Iron-Containing Components from Ash and Slag Material (Coal Combustion Waste) by Magnetic Separation

This article presents the results of research aimed at optimizing the process of recovery of valuable components from ash and slag waste from thermal power plants. In this work, both experimental and theoretical studies were carried out to substantiate the use of magnetic separation methods for ash and slag waste processing. Ash and slag wastes were chosen as an object of research due to the presence of valuable components such as iron, aluminum, etc., in them. The research results showed that the method of magnetic separation, including high-gradient magnetic separation, can be effectively used in ash and slag waste processing. As a result, the topology of a magnetic beneficiation technological scheme has been proposed to obtain high-value-added products such as high-magnetic iron minerals, low-magnetic iron minerals, and aluminosilicate microspheres. By using magnetic separation in a weak magnetic field, magnetic microspheres containing high-magnetic iron minerals associated with intermetallics, ranging in size from 20 to 80 µm, were recovered. In the second stage of magnetic separation (high-gradient magnetic separation), an iron ore product with an iron content of 50% with a recovery of 92.07% could be obtained. By using scanning electron microscopy, it was found that the main part of microspheres, which contain low-magnetic iron minerals and aluminosilicates, with sizes from 2 to 15 microns, was recovered in the magnetic fraction. This paper proposes a new approach to the enrichment of ash and slag materials using magnetic separation, which will increase the efficiency of their processing and make the process environmentally sustainable.

Converting industrial waste into valuable Zn2SiO4/SiO2 nanosheets for highly effective organic dye removal

As a common industrial waste, fly ash is conventionally used as a concrete additive, resulting in the wastage of silicon and aluminium materials and environmental pollution. In this study, we innovatively utilize fly ash waste to synthesize Zn2SiO4/SiO2 nanosheets, which are employed as effective adsorbents for purifying organic dyes such as methylene blue, rhodamine B, and congo red. The Zn2SiO4/SiO2 nanosheets, with a large specific surface area of approximately 81.21 m2 g−1, exhibit enhanced adsorption capacity for organic dyes, in contrast to pure fly ash with a specific surface area of only ∼1.06 m2 g−1. Notably, the Zn2SiO4/SiO2 nanosheets demonstrate a remarkable adsorption capacity of 124.50 mg g−1 for methylene blue, which is ∼120 times higher than pure fly ash. The adsorption kinetics are analyzed using Langmuir and Freundlich models, shedding light on the adsorption mechanism of the Zn2SiO4/SiO2 adsorbent. This study presents an efficient ‘waste-to-treasure’ approach, advocating for the secondary utilization of industrial waste to alleviate environmental pollution.

POROUS FLY ASH-BASED GEOPOLYMER USABLE AS AN UNCONVENTIONAL CONSTRUCTION MATERIAL

Geopolymer foam with thermal insulation properties was made by foaming the alumino-silicate mixture composed of fly ash and clay brick waste activated with alkaline activator (water glass and sodium hydroxide in aqueous solution). Other mixture components were expanded perlite as siliceous additive, usual fine aggregate (quartz sand), and less frequently used surfactant (olive oil). The main characteristics of the geopolymer foam were: low density, low thermal conductivity, and relatively high compressive strength. The residual materials contributed to low costs and the complete replacement of ordinary cement led to the significant reduction of CO2 emissions.

Enhancing concrete performance with e-plastic waste and fly ash: a sustainable approach

Enhancing concrete performance with e-plastic waste and fly ash: a sustainable approach

Precast lightweight concrete wall panels from plastic waste and household ash as partially sand and cement replacement

The present study aims to investigate the properties of precast lightweight concrete wall panels prepared with the addition of plastic powder and household ash as a partial substitution for sand and cement.

ВЛИЯНИЕ ПРИМЕСИ ЗОЛОШЛАКОВЫХ ОТХОДОВ МУСОРОСЖИГАТЕЛЬНЫХ ЗАВОДОВ НА ТЕПЛОПРОВОДНОСТЬ МИНЕРАЛЬНОЙ БАЗАЛЬТОВОЙ ВАТЫ

Basalt fibers are material with unique combination of good mechanical and operational properties at relatively low cost. These properties of basalt fibers are actively used in construction industry to create fibrous thermal insulation materials using both pure basalt and its mixture with other materials. This article examines the effect of ash and slag waste from waste incineration plants on thermal conductivity coefficient and suitability of mixture of basalt with ash and slag waste for production of high-quality fibrous thermal insulation materials. The melt was prepared in plasma energy reactor, with subsequent drawing of mineral fibers on original installation. Resulting mineral fibers were examined to determine thermal conductivity according to standard technique. The study also determined elemental composition of fibers and their average diameter and assessed change in original composition of charge and mineral fibers.

Low permeability sealing materials based on sewage, digestate and incineration industrial by-products in the final landfill cover system

This study explores repurposing municipal solid waste from the sewage, digestate, and incineration industries as landfill-sealing materials, aligning with circular economy principles. The main materials include digested sewage sludge (DSS), pretreated digested sewage sludge (PDSS), and digestate sludge (DS), with biomass bottom ash (BBA) and Al-anodizing waste (AAW) introduced as additives, complemented by 1.5 wt% water glass to enhance the sealing performance. The research evaluates the characteristics of the various treated and sourced sludges and additives, assessing their influence on water permeability, reaction products and the environmental consequences. Results demonstrate the achievement of low permeability in the sludge-based sealing materials, with optimal performance observed in the specimens prepared with DSS and AAW (k value = 3.78 ×10−12 m/s). Thermal Pressure Hydrolysis pre-treatment in sewage plants reduces the organic content in PDSS, resulting in a slight increase in permeability. DS-based specimens exhibit higher permeability due to their relatively lower organic content in DS. Gypsum is the primary reaction product attributed to leachable sulphate in BBA and AAW. Water glass addition in BBA-modified specimens promotes silica gel formation, while AAW effectively reduces matrix permeability as an externally added gel-like substance. Additionally, heavy metals (As, Pb and Cr) derived from the by-products are effectively immobilized in the sealing materials owning to the coagulation effect of organic matter in the sludge and sulphates in the products. Overall, this novel approach to landfill sealing materials exhibits promising applications in the Netherlands, offering cost savings and reduced environmental impact by recycling industrial by-products.

Eco-Friendly Methods of Silica Extraction from Pyrophyllite Rocks Using Sol-Gel versus Alkali Fusion Method

Silica is the most abundant compound on the Earth’s surface. The content of silica can be found in agricultural waste ash and mineral rocks. Extracting silica from natural sources is advantageous due to its economic feasibility and easily obtained. Silica has a wide range of applications, such as in fertilizers, adsorbents, organic reaction catalysis, biofuels/alternative energy production, and as an antimicrobial agent. One type of rock that contains the highest amount of silica is Pyrophyllite. Recent research trends have focused on various methods and sources for silica extraction, yet extracting silica from mineral rocks presents its own challenges. Pyrophyllite rock contains a high amount of silica, but its extraction is quite difficult due to the presence of crystalline silicate mineral phases. This study aims to compare the silica extraction process on Pyrophyllite rocks from Malang using the sol-gel method versus the alkali fusion method.

Improving the thermal properties of lightweight concrete exterior walls

This article is devoted to the development of energy-efficient porous expanded clay concrete for exterior walls. Experimental data confirming the expediency of designing the optimal composition of porous concrete according to the general method of designing the optimal composition of the general theory of artificial building conglomerates (ABC) are presented. The presence of waste ash from thermal power engineering and a complex gas–forming agent based on the polymer K-9 reagent in the concrete provided increased durability, improved humidity and thermal engineering conditions of porous concrete.

Insight into heavy metal chemical fractions in ash collected from municipal and industrial waste incinerators in northern Vietnam.

This investigation involved the collection of fly ash and bottom ash specimens from seven waste incinerators situated in the northern provinces of Vietnam, aimed at assessing the composition and distribution patterns of five chemical fractions of heavy metals (Pb, Cr, As, Cd Cu, and Zn) present in incinerator waste ash. The outcomes reveal that fly ash exhibited a relatively elevated concentration of industrial waste metals (25-66%) such as As, Cd, and Pb primarily in exchangeable (F1) and carbonate fractions (F2), which are mobile forms susceptible to environmental dissolution and consequential bioaccumulation posing health risks to humans. The predominant states of the metals Cr, Cu, and Zn were identified as residual, Fe-Mn oxide, and carbonate, respectively, with their relative proportions showing minimal variation. Conversely, heavy metals were predominantly present in residual residue and Fe-Mn bound form (F3) in bottom ash derived from both residential and commercial waste incineration operations. The non-carcinogenic hazard indices (HI) associated with the examined metals, ranked for both adults and children, were as follows: Pb > Cr > As > Cd > Cu > Zn. Notably, the HI values for Pb, Cr, and As exceeded the permissible threshold (HI > 1) for children. However, the risk of As, Cd, and Pb-related cancer via exposure pathways remained within acceptable limits for both age groups. Conversely, the probability of carcinogenic effects attributable to Cr surpassed the permissible threshold (>10-4), indicating significant health concerns associated with heavy metals in waste incinerators for humans, particularly children.

Mechanical behavior of silty-clayey lateritic soil stabilized with recycled municipal solid waste ash

Due to the ever growing need to incorporate ecofriendly and sustainable materials in construction projects, this research study was carried out with the purpose of exploring the feasibility of utilizing recycled municipal solid waste ash (RMSWA) as a sustainable material for stabilizing clayey lateritic soils (LS).The research was aimed at investigating the effect of incorporating varying amounts of RMSWA on the engineering properties of weak soils. Laterite specimens were incorporated with the varying ash contents at intervals of 3%, 6%, 9%, 12% and 15% as replacement levels, and tested for Atterberg limits, compaction and unconfined compressive strength (UCS) behavior. The scanning electron microscopic (SEM) test was conducted to determine the morphology changes in the soil when blended with RMSWA contents at curing ages of 1, 7 and 14 days. Based on the results of UCS test, stress - strain behavior, load - deformation relationships curves were also established and analyzed. Results from the Atterberg limit test revealed that the plastic index, plastic limit, liquid limit ranged between 1.6-11.9%, 20.6-24.5% and 26.1-35.0%. The maximum dry density of the samples increased with the ash inclusion, with the maximum dry density value of 2020Kg/m3 achieved at 6% ash inclusion, thus making it suitable in laterite stabilization.

Hydrothermal Conversion of Fly Ash into Monomineralic Zeolite Synthesis for Biodiesel Production

Abstract Fly ashes as a residue from combustion processes of coal in coal-fired power stations can be applied for zeolite formation. The zeolite synthesis has considerable effect on their structure following further catalytic use. The formation of analcime is guided by the operation of the silicate framework in the company of Na+, [Al(OH)4]−, [H2SiO4]2− species, coming from fly ash processing. Here, we have highlighted the importance of conducting the coal fly ash waste management towards monomineralic zeolite synthesis, in the form of powder analcime. It is the first report on powder analcime production without fly ash residues, confirmed by SEM and XRD analysis. The obtained analcime-zeolite was further explored as biodiesel catalyst based on base-catalyzed transesterification process. The effect of analcime catalyst usage on the biodiesel yield was determined with observed 97.2 % conversion efficiency under the concentration of 4%wt at 230 °C, with three times reusable analcime catalysts. Coal fly ash-derived monominerals on a large scale can significantly contribute to the sustainability goals and efficient waste management.

Retracted: Determination of Adsorption of Methylene Blue Dye by Incense Stick Ash Waste and Its Toxicity on RTG-2 Cells

Retracted: Determination of Adsorption of Methylene Blue Dye by Incense Stick Ash Waste and Its Toxicity on RTG-2 Cells

Phase transformation and strength of hydrated circulating fluidised bed combustion ash sediment in an open environment over 15 years: implications for the long-term stability of ash waste plateaus

Phase transformation and strength of hydrated circulating fluidised bed combustion ash sediment in an open environment over 15 years: implications for the long-term stability of ash waste plateaus

To Study the Concrete by Partial Replacement of Cement with Tobacco Waste and Bamboo Leaf Ash with Addition of Sugarcane Fibre

Abstract: The demand for concrete is growing with the growing demand for infrastructure, energy and resources. One of these harms comes from the large emission of carbon dioxide gases during the manufacturing procedure of cement. The leaves, when dried and burnt, produce ashes that have been found to be pozzolanic. The carbohydrate content in bamboo plays an important role in its strength and in improving its health. The partial replacement of aggregates is need for the future generation of concrete structures for the environment supportable. The depletion of the natural resources gets exhausted. We have think over the alternate replacement of the materials. In present work the partial replacement of the TWA and BLA with the Cement and addition of sugarcane fibers. The optimum percentage that was noticed, was at 12&12% of cement was replaced Tobacco waste ash and Bamboo leaf ash and for reinforcement 0.6% of addition Sugar cane fibers was used. The workability of mixture increases and after that there is decrease in the workability of the concrete when we increase the percentage of TWA and BLA. A series of experiment were carried out to measure the compressive strength, split tensile strength and flexural strength of the concrete. The results showed that the compressive strength, split tensile strength and flexural strength increases with the adding TWA and BLA with the Cement with addition of sugarcane fibers.

Pertumbuhan Tanaman Tomat (Solanum lycopersicum) dengan Media Abu Terbang (Fly Ash) dan Abu Dasar (Bottom Ash)

The use of fly ash and bottom ash as a plant medium can reduce waste from burning coal. The ash waste contains micro and macro nutrients that plants can use for growth. The ash contains the elements Na, K, Ca, Mg, Cu, Zn, and MN. This research aims to determine the effect of fly ash, bottom ash, and their combination on the growth of tomato plants (Solanum lycopersicum). This research used RAL (Completely Randomized Design) with 12 factors and 3 replications, namely k0 (negative control, not given anything), k1 (positive control, given urea fertilizer), a1 (400 g/polybag fly ash), a2 (800 g/polybag fly ash), a3 (1200 g/polybag fly ash), b1 (400 g/polybag base ash), b2 (800 g/polybag base ash), b3 (1200 g/polybag base ash), ab1 (200 g/polybag fly ash + 400 g/polybag fly ash), ab2 (400 g/polybag fly ash + 200 g/polybag fly ash), ab3 (600 g/polybag fly ash + 400 g/polybag fly ash), and ab4 (400 g/polybag fly ash + 600 g/polybag fly ash). The observation variable is the growth of tomato plants, including plant height, number of leaves, number of branches, stem diameter and wet weight. The results showed that there was an effect of using fly ash and bottom ash as a planting medium on the growth of tomato plants for 90 DAP in the AB4 treatment. The combination of 400 g/polybag fly ash + 600 g/polybag fly ash gave good results in plant height, number of leaves, number of branches, and fresh weight of tomato plants, but in terms of branch diameter, NPK treatment gave good results.

Effect of green gram pod ash (GGPA) as supplementary cementitious material (SCM) in mechanical and durability properties of concrete

Agriculture waste generation is increasing daily, and agricultural waste management has become one of the most challenging issues for many countries. To contribute towards a sustainable waste management system, this experimental study evaluates the impact of using agricultural waste materials in concrete. Concrete that does not harm the environment and has improved engineering properties can be produced using agricultural waste ash such as green gram pod ash. Green concrete has been examined for its mechanical, durability and microstructure properties when partially replaced with Portland cement by green gram pod ash (GGPA). Conducting various tests using concrete containing different weight proportions of green gram pod ash in a mix at 2%, 4%, 6%, 8%, and 10%, respectively. This paper examines the mechanical, durability and morphological characteristics of green gram pod ash blended with cement concrete. It has been shown that concrete containing 8% green gram pod ash enhances the properties of GGPA concrete. It was observed that the addition of 8% green gram pod ash enhances the compressive strength. Split tensile strength, flexure strength, modulus of elasticity and impact strength of concrete by 4.26%, 4.07%, 35.19%, 16% and 10.3% at 28 days of curing. It was concluded that green gram pod ash was shown to satisfy engineering application design requirements and significantly reduce concrete production costs and environmental pollution. The cement replacement with 8% of GGPA is optimum for achieving better concrete properties.

Production and Characterization of Bricks from Bottom Ash and Textile Sludge Using Plastic Waste as Binding Agent

The production of traditional clay bricks consumes a large amount of energy and resources and can lead to the depletion of natural resources like clay. On the contrary, the improper disposal of waste materials such as bottom ash, textile sludge, and plastic waste can lead to environmental pollution and health hazards. Bricks and concrete blocks have been widely used in construction, but the continuous exploitation of raw materials can negatively impact the environment. This study aimed to produce bricks made from municipal solid waste, incinerated bottom ash, and textile sludge, using plastic waste as a binder. It assessed the potential use of these bricks as an alternative material for brick block production. The physical and chemical characteristics of the raw materials were determined using standard test methods. The crushed plastic waste was melted and mixed with dried textile sludge and bottom ash in various ratios, including 1 : 1 : 1, 2 : 1 : 1, 1 : 2 : 1, 1 : 1 : 2, and 1 : 2 : 2 for plastic, municipal incinerated bottom ash, and textile sludge, respectively. The mixed sample was then placed into molds until it dried, and the resulting bricks were tested for compressive strength, water absorption, efflorescence, and leachability. The results indicated that the bricks had suitable physical and chemical properties, with compressive strength ranging from 8.527 to 16.4 MPa and water absorption percentages ranging from 1.3 to 3.4%. Slight efflorescence was observed for the 1 : 2 : 2 ratios. The production of traditional clay bricks consumes a large amount of energy and resources and can lead to the depletion of natural resources like clay. On the other hand, the improper disposal of waste materials such as bottom ash, textile sludge, and plastic waste can lead to environmental pollution and health hazards.