Chair of Metallurgy of Non-ferrous Metals, National Mineral Resources University, Saint Petersburg, Russia

V. M. Sizyakov, Professor, e-mail: kafmetall@mail.ru
V. Yu. Bazhin, Assistant Professor
A. A. Vlasov, Engineer-Metallurgist
R. Yu. Feschenko, Engineer-Metallurgist

Features of modern aluminum reduction cells are to produce an uneven dynamics of the melt, spent carbon anodes and distribution of coal in the foam volume of the alumina-cryolite electrolyte. The formation of carbon foam in the electrolyte leads not only to increase its electrical resistance but reduce current efficiency by closure to metal pad and the anode to improve the over consumption of the prebake anode and also changes in the conditions of alumina dissolution. The physical and chemical characteristics of alumina dissolution and an electrolyte containing of different amounts of carbon are discussed in this paper. The established models of alumina dissolution, content elementary and dissolute carbon are components of the discrete feeding algorithmic technology for alumina feeding systems of aluminum reduction cell. This technology enables the effective of alumina dissolution at the expense of filing for each individual feeder signal in order to load the maximum amount of alumina into capable dissolving in the electrolyte without formation of anode effects and the alumina-cryolite sludge. The strategy of this technology is based in the kinetics of the interaction between electrolyte and alumina for providing a highly effective of alumina dissolution in the anode-cathode distance. Such technical decision increases current efficiency, decreases consumption of prebake anodes and energy for aluminum reduction process.

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