St. Petersburg State Marine Technical University (St. Petersburg, Russia):

Nifontov Yu. A., Head of Chair, Doctor of Engineering Sciences, Professor, nifontov@yandex.ru

REC «Mekhanobr-Tekhnika» (St. Petersburg, Russia):

Lazareva V. V., Senior Research Engineer, lazareva_vv@npk-mt.spb.ru

Our domestic aluminum industry is highly import-dependent as regards the original high-grade mineral raw materials. The Russian Federation has huge reserves of high-silica aluminum ores requiring highly complex chemical and metallurgical processing into alumina (aluminium oxide), competitive technologies for which have not yet been commercially developed. High-silica raw materials include nepheline ores, kaolins, anorthosites, sillimanite group minerals, as well as the man-made product of fly ash of thermal power plants. The first two types of raw materials have the highest potential value for the aluminum industry. However, none of the potential high-silica raw materials for alumina production are suitable for direct chemical and metallurgical processing, primarily due to the high content of impurities, such as silicon oxide and iron oxides. These materials require special grain size-based processing and preparation technologies. The situation on the global market for alumina and aluminum calls for further reductions in energy consumption and product costs in order to ensure improved competitiveness. One of the possible ways to reduce costs of the sintering process in alumina production is to select and implement lower cost and higher quality fuel. The analysis of previous studies and of the practice of existing enterprises in the field of preparation of process fuels based on low-grade brown coal shows that further research in this area should be carried out for the drying and grinding technologies and medium-temperature pyrolysis of the original coal.
The study was carried out under the grant issued by the Russian Science Foundation (project No. 18-17-00169).

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