Vol. 337 No. 5 (2026)
DOI https://doi.org/10.18799/24131830/2026/5/5557
Assessment of the efficiency of Reftinskaya GRES fly ash enrichment by various methods
Composite materials based on glass fibers are widely used in various branches of technology: aerospace, defense, construction, etc. Along with the development of fiberglass production technologies, it is important to carry out advanced work aimed at finding affordable and inexpensive raw materials, as well as developing effective technological solutions for glass fiber production. Such solutions should facilitate their implementation in industrial production without significant adjustments to technological schemes and process parameters. Fiberglass made from magnesium aluminum silicate glass is most often used as fillers in fiberglass. The similarity of the total content of silicon and aluminum oxides in thermal power plant fly ash with the compositions of such glasses suggests the possibility of their effective use as the main component of the glass charge. The aim of the study was to evaluate the efficiency of Reftinskaya GRES fly ash enrichment using known technological methods, since the high content of iron oxides (FexOy) is a key limitation determining the success of using fly ash as a traditional raw material in fiberglass technology. Modern instrumental methods were used in the work, including scanning electron microscopy, which made it possible to identify the morphology of fly ash, as well as X-ray phase and X-ray fluorescence analyses, which were used to determine the mineralogical and chemical compositions of fly ash. The enrichment efficiency was determined using laboratory equipment that provided the processes of magnetic and electrostatic separation, forward and reverse flotation. It was found that the combined use of magnetic and electrostatic separation makes it possible to reduce the content of FexOy by 55 %, while its content in ash was 2.88 wt. %. Less effective was the enrichment of fly ash by joint magnetic separation and flotation, in which the content of iron oxides in glass was 3.73 wt. %. It is proved that the resulting After enrichment of the Reftinskaya GRES fly ash, the aluminosilicate product is characterized by a total content of oxides forming the structural grid of glass (SiO2+Al2O3) up to 91.44 wt %. Therefore, it can be effectively used as the main component of the glass charge for the production of high-modulus magnesium alumosilicate glasses. When calculating the charge recipes, it was found that the content of enriched fly ash at Reftinskaya GRES can reach from 50 to 80 %, therefore, such charges can be considered technologically feasible and economically advantageous.
For citation: Onischuk V.I., Lazarova Yu.S., Ivleva I.A., Panova O.A. Assessment of the efficiency of Reftinskaya GRES fly ash enrichment by various methods. Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering, 2026, vol. 337, no. 5, pp. 203-217. https://doi.org/10.18799/24131830/2026/5/5557
Keywords:
fiberglass, fly ash, iron role in glass, enrichment, magnetic separation, flotation, Reftinskaya GRES, composites, raw materials for glass
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