The sphere of application of kaolin ores in the aluminum industry may expand in the future.
Researchers at St. Petersburg Mining University have developed an effective technology for producing alumina by sintering kaolin ores with limestone and adding carbon-containing activating additives. The specialists have managed to find the optimal content of additives, at which the increase in aluminum oxide extraction was more than 7%. The highest efficiency is achieved when the proportion of carbon in the charge ranges from 1.5% to 3%, depending on the nature of the carbonaceous material.
The gradual depletion of high-quality bauxite deposits with the increase in the world demand for aluminum dictates the need to look for alternative raw materials. This could be, for example, nepheline rocks, low-quality bauxites, clays, and kaolin ores. The latter, according to Mining University researchers, can claim to be more widely used in the industrial production of alumina.
A significant effect of the new technology is also a reduction in the cost of grinding the limestone- kaolin charge because of the self-dissipation effect. Alumina extraction at this technology reaches 93.5%. And the index does not radically depend on the chemical composition of the initial kaolin ore.
Kaolin ores are especially relevant for countries that have no big reserves of bauxite and nepheline, like Egypt, for example. It is no coincidence that the research group headed by Vyacheslav Brichkin, Doctor of Engineering, includes Eldib Amr Basyuni Saad, a postgraduate of the Department of Metallurgy of Mining University, who also represents Al-Azhar University in Cairo.
Let us remind you that the Department of Chemical Technology and Energy Processing of St. Petersburg Mining University has also obtained synthetic additives that significantly improve the low-temperature properties of fuels.
