National Mineral Resources University (University of Mines) (Russia):

Sizyakov V. М., Doctor of Engineering Sciences, Professor

Dubovikov О. А., Doctor of Engineering Sciences, Associate Professor, dubovikov_oa@mail.ru

Loginov D. A., Postgraduate, denis90-01@mail.ru

The paper presents a comprehensive analysis of the current state in alumina industry and possible prospects of drawing lower grade bauxite into processing. A universal technique for thermo-chemical treatment of lower grade bauxite with complex chemical-and-mineral composition has been chosen and studied, with the engineering solutions fitting naturally into the existing alumina production flowsheet. New data are presented upon main bauxite-forming minerals behavior in chemical processing without their preliminary thermal activation and following such activation, upon complex systems components interaction mechanism in alkali-containing solutions, upon alkali solutions regeneration and return to the process. The results of the studies, performed by the leading scientific school of the National Mineral Resources University (University of Mines), on which basis the technological solutions may be substantiated with a view to provide for a significant enlargement of the alumina industry raw-materials base through drawing lower grade high-silica bauxites into processing.

The paper was written with the aid of the financial grant from the Ministry of Education and Science of the Russian Federation in the framework of the State task in scientific activities in the year of 2014.

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