Adsorption performance of calcium-aluminum layered double hydroxides synthesized from waste incineration fly ash for removal Pb(II) from water

In this study, municipal solid waste incineration (MSWI) fly ash was subjected to mineral carbonation with the aim of investigating CO2 sequestration in waste material. The conducted study follows the trend of searching for alternatives to natural mineral materials with the ability to sequestrate CO2. The mineral carbonation of MSWI fly ash allowed for the storage of up to 0.25 mmol CO2 g-1. Next, both carbonated and uncarbonated MSWI fly ashes were activated using an alkaline activation method by means of two different activation agents, namely potassium hydroxide and potassium silicate or sodium hydroxide and sodium silicate. Mineral carbonation caused a drop in the compressive strength of alkali-activated materials, probably due to the formation of sodium and/or potassium carbonates. The maximum compressive strength obtained was 3.93 MPa after 28 days for uncarbonated fly ash activated using 8 mol dm-3 KOH and potassium hydroxide (ratio 3:1). The relative ratio of hydroxide:silicate also influenced the mechanical properties of the materials. Both carbonated and uncarbonated fly ashes, as well as their alkali-activated derivatives, were characterized in detail by means of XRD, XRF, and FTIR. Both uncarbonated and carbonated fly ashes were subjected to TG analysis. The obtained results have proved the importance of further research in terms of high-calcium fly ash (HCFA) utilization.

Thermal co-treatment of combustible hazardous waste and waste incineration fly ash in a rotary kiln

For the purpose of solid waste co‐disposal and heavy metal stabilization, foam glass–ceramics were produced by using municipal solid waste incineration (MWSI) bottom ash and fly ash as main raw materials, calcium carbonate (CaCO 3 ) as foamer and sodium phosphate (Na 3 PO 4 ) as foam stabilizer. The influences of the raw material composition, foaming temperature and foaming time on the properties were investigated. Porosity, bulk density, mechanical property and leaching of heavy metals were analyzed accordingly. The product, foamed at 1150 °C for 30 min with 14% fly ash and 74% bottom ash, exhibits excellent comprehensive properties, such as high porosity (76.03%), low bulk density (0.67 g·cm −3 ) and high compressive strength (10.56 MPa). Moreover, the amount of leaching heavy metals, including Cr, Pb, Cu, Cd and Ni, in foam glass–ceramics is significantly lower than that of the US EPA hazardous waste thresholds. This study not only realizes the integrated utilization of bottom ash and fly ash, but also addresses a new strategy for obtaining foam glass–ceramics.

Washing pre-treatment of municipal solid waste incineration (MSWI) fly ash blended with shale and sludge was utilized in the manufacture of light-weight aggregates and processed to form ceramic pellets. A formula uniform design was performed to arrange the mixture ratio of the materials. The optimal mixture ratio of the materials was determined by measuring the bulk density, granule strength, and 1 h water absorption of the pellets. It is shown that the optimal mixture ratios of materials, MSWI fly ash, shale, and sludge, are 23.16%, 62.58%, and 14.25% (mass fraction), respectively. The performance testing indicators of light-weight aggregates are obtained under the optimum mixture ratio: bulk density of 613 kg/m3, granule strength of 821N, and 1 h water absorption of 11.6%, meeting 700 grade light-aggregate of GB/T 17431.2—1998 standard. The results suggest that utilization of MSWI fly ash in light-weight aggregates is an effective method and a potential means to create much more values.

Resource utilization of municipal solid waste incineration fly ash in iron ore sintering process: A novel thermal treatment

A novel amine functionalized porous geopolymer spheres from municipal solid waste incineration fly ash for CO2 capture

The safe and resource-efficient utilization of waste incineration fly ash (WIFA) has emerged as a pressing challenge in solid waste management. In this work, WIFA was used to prepare a bifunctional catalyst (Metalsx/4@WIFA-S) for the production of levulinic acid (LA) from glucose. The yield of LA was 42.3% with water as the solvent. Moreover, adding 20% γ-valerolactone (GVL) to the system increased the yield to 50.7%. Reaction kinetics and molecular dynamics simulations were applied to elucidate the mechanism by which the solvent system enhanced the catalytic performance of the Metalsx/4@WIFA-S catalyst. Additionally, the environmental risks of WIFA in the preparation of catalysts were evaluated. The dioxin decomposition rate in the catalyst was calculated to be 99.87%, effectively achieving the detoxification of the catalyst. The concentration of heavy metals in the hydrolysate complied with emission standards, thereby reducing environmental risk. This study confirms that waste incineration fly ash-based bifunctional catalysts are effective and safe catalysts with great potential for application in biomass catalysis.

Utilization of municipal solid waste incineration fly ash as construction materials based on geopolymerization

Utilization of municipal solid waste incineration (MSWI) fly ash in ceramic brick: Product characterization and environmental toxicity

Utilization of MSWI fly ash for stabilization/solidification of industrial waste sludge

Utilization of coal gangue and waste incineration fly ash under high temperature sintering in cementitious materials: Physico-Mechanical properties and hydration products

To realize the utilization of andesite tailings and solve the environmental problems caused by municipal solid waste incineration (MSWI) fly ash, both of them were selectively used as raw materials to prepare glass ceramics by sintering process. The effects of components on the properties of glass ceramics were analyzed. The results showed that glass-ceramic sample 21 prepared from andesite tailings and MSWI fly ash had the best performance, the bending strength was 94.8Mpa. At the same time, its acid and alkali resistance were the best, while the thermal conductivity was the lowest. The leaching of heavy metal elements in all the samples met the Chinese national standard. These results will provide some reference for the resource utilization of andesite tailings and MSWI fly ash.

Sufficient attention should be attached to the large amount of fly ash containing high levels of toxic heavy metals generated after municipal solid waste incineration. Because heavy metals could be leached out of the fly ash under specific conditions, it is necessary to stabilize the heavy metals in fly ash before landfill disposal. Processing technologies of incineration fly ash include solidification/stabilization technology, thermal treatments, and separation processes. This study reviewed the current treatment technologies of municipal solid waste incineration (MSWI) fly ash, with the main focus on the treatment of heavy metals in fly ash with chemical stabilization. Chemical stabilization processes involve chemical precipitation of heavy metal and chelation of heavy metals. In multiple studies, chemical stabilization technology has shown practical feasibility in terms of technology, economy, and effect. In addition, the combination of two or more stabilization agents broadens the general applicability of the agents to heavy metals and reduces the cost. The application of joint processing technology realizes the remove of soluble salt from fly ash. To minimize pollutants while increase their usable value, effective use of waste and co-disposal of several kinds of wastes have gradually become the research hotspots. New developments in chemical stabilization are progressively moving towards the sustainable direction of harmlessness and resource utilization of MSWI fly ash.

Utilization of municipal solid waste incinerator fly ash under high temperature sintering and alkali excitation for use in cementitious material

Sustainable utilization of municipal solid waste incineration fly ash for ceramic bricks with eco-friendly biosafety