Extraction of valuable components from ash and slag waste from layered coal burning

The results of research on the complex processing of ash and slag waste from the layered combustion of coal, aimed at obtaining aluminum-containing raw materials and other demanded products, are presented. Reducing the volume of ash and slag waste stored ensures the environmental safety of energy sector production facilities and the possibility of their uninterrupted and efficient operation. The advantage of consistent use of waste enrichment methods – flotation, magnetic separation, and leaching is the ability to separate the source material into several commodity products, each of which is enriched with a specific component, which expands the range of secondary raw materials used in industry. As a result of the study of the flotation process, the optimal particle size (–0.63+0.071 mm) for obtaining a carbon-containing product was determined. A high efficiency of magnetic separation (extraction of up to 90.53% Fe) of carbon-depleted flotation tailings with a magnetic induction value of 60 Mt has been established. The rationality of preliminary ultrasonic processing of materials of small size classes with the possibility of reducing magnetic induction to 40 MT is substantiated. The optimal mode of charge humidification during alkaline roasting of magnetic enrichment waste has been determined. A comparative assessment of acid and alkaline leaching has been carried out and the high efficiency of acid leaching has been shown. A combination of several reagents (HCl, H2SO4, and an oxidizer) resulted in the greatest recovery of aluminum and other valuable elements such as manganese, cobalt, and zinc, with the lowest silicon content in the filtrate.

Lavrinenko A. A., Kunilova I. V., Krylov I. O., Pisareva A. A. Extraction of valuable components from ash and slag waste from layered coal burning. MIAB. Mining Inf. Anal. Bull. 2025;(9-1):90-102. [In Russ]. DOI: 10.25018/0236_1493_2025_91_0_90.

A.A. Lavrinenko¹, Dr. Sci. (Eng.), Chief Researcher, Head of Laboratory, e-mail: lavrin_a@mail.ru, ORCID ID: 0000-0002-7955-5273,
I.V. Kunilova¹, Cand. Sci. (Eng.), Senior Researcher, e-mail: kunilova_i@ipkonran.ru, ORCID ID: 0000-0002-7775-085X,
I.O. Krylov¹, Cand. Sci. (Eng.), Senior Researcher, e-mail: krylov_i@ipkonran.ru, ORCID ID: 0000-0002-8174-9210,
A.A. Pisareva¹, Engineer; Master's Student, D. Mendeleev University of Chemical Technology of Russia, 125047, Moscow, Russia, e-mail: pisareva_a@ipkonran.ru, ORCID ID: 0009-0004-4699-4853,
¹ Institute of Comprehensive Exploitation of Mineral Resources Russian Academy of Sciences, 111020, Moscow, Russia.

A.A. Lavrinenko, e-mail: lavrin_a@mail.ru.

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