Papers by Keyword: Ash

Abstract: The scope of generation, accumulation and use of ash and slag waste of thermal power plants in different countries has been analyzed. The results of the study of the phase, mineralogical and chemical composition of ash and slag waste obtained with the dominance of solid and liquid fuel in the energy balance have been presented. It has been shown that the newly formed and previously accumulated ashes and slags of thermal power plants, with their correct and effective use, are a powerful source of expansion of raw materials in various industries. The existing methods of using ash and slag waste, which have been developed based on their mineral composition and the content of trace elements and impurities in them, have been considered. The most effective application of these wastes is in the construction industry, as well as when used as a raw material for obtaining compounds of rare metals, for example, vanadium.

Abstract: The author analyzed technological solutions for the production of blocks from soil cement. It is proposed to make soil cement blocks from portland cement brand 400 in the amount of 20 % of the mass of soil and water. Experimental addition of fly ash to the solution in different amounts depending on the cement content. It is proposed to add ash removed from the Darnytsya thermal power plant, which was sifted through a 4 mm sieve, because the ash contains a significant amount of impurities. The content of inclusions from 1 to 4 mm was up to 40 %. It is proposed to make blocks from soil cement with the addition of fly ash with the aim of improving the thermotechnical properties. It is proposed to make soil-cement blocks with two voids. To ensure high-quality compaction of products in forms, the moisture content of the content for most soils should be within 14–23 %. The maximum force that the sample can withstand was taken as a destructive load. It was decided that the use of fly ash as part of the mixture in the production of soil cement gives a positive effect. With an increase in the period of exposure of samples in water to 90 days, the average compressive strength of soil cement samples without additives and with the addition of the appropriate percentage of fly ash increases.

Abstract: Sustainable development objectives in the construction sector is currently hampered by the high cost of materials (cement, aggregates) and the environmental impact of waste in some developing countries. The obtained results in this work on the influence of ash (PKSA) and palm kernel shell (PKS) used as a partial addition of cement and aggregates in concrete composition, enable their valorization as local materials to manufacturing the lightweight concrete with low-cost. This is an interesting contribution to the development of sustainable construction and environmental protection. The used palm kernel shells are produced in the palm oil industry in Republic of Congo. The highest values for density Cd(2348kg/m³), compressive strength Cs(27MPa) and splitting tensile strength Ts(2.4MPa) for concrete using PKSA were obtained at 2.5%. Those for concrete using PKS were obtained at 5 %, i.e. Cd(2165kg/m³), Cs(22MPa) and Ts(1.90MPa). the increase in concrete properties with PKSA compared to PKS is explained by the pozzolanic reaction of the palm kernel ash, which acts as a hydraulic binder. Correlations between fundamental concrete properties reliably describe the influence of PKS and PKSA, with a coefficient of determination R² (0.9) superior at 0.5; the obtained mathematical models to prediction the concrete properties are a significant contribution for engineers. PKS is a concrete plasticizer, PKSA is a concrete setting and hardening accelerator. The production of low-carbon concrete with PKSA addition is a major step forward for the concrete industry.

Abstract: Photoresist after implantation is commonly removed either by wet chemical dissolution with sulfuric acid, or by dry ash stripping followed with a wet cleaning. To prevent any photoresist residues, sulfuric acid is still conserved in post ash cleans as additional safety. However, by ensuring sufficient over ash time, SPM (Sulfuric acid Peroxide hydrogen Mixture) chemical need becomes less essential. This paper reevaluates the benefit of SPM after dry ash stripping regarding the environmental context. The advantages of dry ash stripping with clean, compared to wet stripping are outlined. The study introduces prior analyses on defectivity and material consumption. Finally, device matching and yield stability, defined as the main success criteria, are described.

Abstract: Known technological solutions for well drilling waste utilization are analyzed. The technological decision of the device of storage of drilling waste from soil-cement elements with the device of a covering from soil-cement is offered. It is proposed to fill the repository with waste in layers of drilling mud, site soil, using a layer of composition for neutralization with the use of ash burning wood residues. The composition is proposed to be prepared near storage facilities. It is proposed to make the neutralizing composition periodically in the sludge storage as they are filled. In the case of a high level of sludge contamination with petroleum products, sorbents are added in addition to filling the storage. The thickness of the layers is chosen based on optimal humidity. It is offered to add ash from the Mykolayiv thermal power plant in the amount of 5 wt.% By weight of cement when installing the walls and covering the sludge storage from soil cement. It was found that with increasing the shelf life of samples in water to 270 days increases the average compressive strength of soil cement samples without additives and with the addition of the appropriate percentage of fly ash by more than 7%.

Abstract: In this paper, we will study the development and comparison of characteristics and thermal properties of original celadon glazes and celadon glazes developed by adding black rice husk ash, Using Mae Rim black clay in Chiang Mai Province as raw material for the original celadon glaze (CG), including clay in the rice paddies, Kha wood ash and mixed wood ash. The raw materials for the development of celadon glazes formula were 14BR, 15BR, 20BR, 21BR, 27BR and 28BR, respectively. Using a triangular phase diagram system, Mae Taeng clay (MT), Kha wood ash (KWA) and black rice husk ash (BR) were used in the ratios of 40, 50, 60 and 70 wt.%, and using the red clay from Doi Saket, Chiang Mai as a coloring agent. Subsequently, the raw materials are ground and mixed to form a coating. Coated onto Mae Rim black clay test specimens. and fire the test specimen at 1250 °C in a reducing atmosphere. After that, the characteristics of the glazes after firing were tested, including crack, melt, flow, color appearance, and chemical composition. Thermal properties tests include the coefficient of thermal expansion and thermal shock resistance in temperature. The results showed that by comparing the original formula celadon glazes (CG) with the celadon glazes formula developed by adding black rice husk ash. crazing were reduced when adding more black rice husk ash. All formulations were melted at 1250 °C due to their CaO content of 55.0, 47.6, 41.0, 51.0, 47.9, 47.7 and 43.0 % respectively. From the chemical composition analysis with XRF, celadon glazes after firing in all formulas did not see any flow due to the content of SiO₂ being 28.0, 28.8, 35.4, 26.7, 28.3, 27.9 and 31.1% respectively. The appearance of glazes after firing was more greenish-yellow when rice husk ash was added when using a color analyzer. Because the amount of Fe₂O₃ up to 4.6, 9.3, 10.4, 8.2, 9.1, 5.9 and 6.0% respectively from Mae Taeng clay and Doi Saket clay. The chemical composition of celadon glaze consists of CaO as the main component, followed by SiO₂ and Fe₂O₃. The important thing is the chemical composition of the glazes was not found with lead and cadmium. The thermal expansion coefficient of celadon glazes at 25-1250°C decreased when adding more black rice husk ash. Finally, the percentage of strength loss after thermal shock temperature change was CG ˃ 20BR ˃ 21BR ˃ 27BR ˃ 28BR ˃ 14BR ˃ 15BR, respectively, using the Celadon Pottery Community Standards Test. (MorChor. 245/2013).

Abstract: The issues of ecology and economics of the use of solid organic fuels for the production of thermal and electric energy, as well as the disposal of their combustion products, are becoming more and more relevant not only in our country, but also in world practice. The formation of industrial waste, in particular ash and slag waste, creates a number of difficulties. One of the main ones is a violation of the environment, which is also relevant for the Arctic zone of the Russian Federation. On the territory of the Arctic zone of the Russian Federation, along with hydroelectric power plants, nuclear power plants and thermal power plants operating on gaseous and liquid fuels (fuel oil), a significant share (on average, at least 20%) is taken by coal generation. An equally urgent problem of the Arctic zone of the Russian Federation is the problem of road construction in permafrost conditions and extreme climatic conditions.

Abstract: The results of the studies on the creation of self-compacting fine-grained fiber-reinforced concrete based on run-of-crusher stone with the use of a polyfunctional additive D-5 are presented. Compositions of self-compacting fine-grained fiber-reinforced concrete with the use of basalt fiber have been developed, which significantly reduce cement consumption and improve the characteristics of fine-grained concrete mixture and concrete. Using a polyfunctional additive D-5in mixtures makes it possible to increase the strength properties of fine-grained fiber-reinforced concrete while improving the concrete mixtures’ rheological characteristics. Replacement of cement up to 10% of the mass by ash fraction d<0.14 min fine-grained concrete mixtures does not cause a noticeable decrease in the concrete strength properties. The developed self-compacting fine-grained fiber-reinforced concretes have increased strength properties and have a low-cost price due to the use of local raw materials and run-of-crusher stone.

Abstract: In the present work, the environmental impacts of the concrete made with woody fly ash that presented compressive strength like the conventional concrete were evaluated and compared using the Life Cycle Assessment methodology. The impact assessment method used was the “CML-IA baseline” implemented in SimaPro software. The results showed that concrete with fly ash had a lower impact than conventional concrete in all the impact categories under study and may be classified as an eco-material (eco-concrete) considering that the environmental issues that are minimized are waste reduction, reduce of landfill problems and resource saving by the utilization of recycled materials.

Abstract: The article presents a study of the physical and technical properties of ash and slag waste Coal Power Plant. The main problem when using ash-slag mixtures is the variability of the particle size distribution of the material. Determining the characteristics of slag stored in the dumps of thermal power plants will help to choose the separation methods of this material, to address the disposal and accumulation of industrial waste, to expand the scope of their application. The obtained research results of physical and technical properties of waste of the Coal TPP testify to wide potential in the further use in many branches of the industry. Possible applications include fillers for concrete, materials for sandblasting (abrasive material), raw materials for the metallurgical industry, additives for the manufacture of binders, etc.