Institute of Non-Ferrous Metals and Materials Science, Siberian Federal University, Krasnoyarsk, Russia:

N. V. Belousova, Head of a Chair of Non-ferrous Metals Metallurgy
N. A. Sharypov, Senior Lecturer of a Chair of Automation of Production Processes in Metallurgy
S. G. Shakhray, Assistant Professor of a Chair of Technosphere Safety of Mining and Metallurgical Production, e-mail: shahrai56@mail.ru
A. I. Bezrukikh, Assistant Professor

The article is devoted to an important topic in the current aluminium industry — the reduction of the amount of dust formed during electrolysis. In a short literature review of foreign works on the problem of reducing the anode consumption, the sources of formation of dust in an aluminium reduction cell and its negative effect on the electrolysis process parameters are analysed: increasing the electrolyte resistance, increasing the electrolyte’s temperature and the loss of fluoride by evaporation, the risk of formation of anode spikes. Spikes can provoke short circuit of the anode and cathode and thus reduce the current efficiency, cause deterioration of alumina solubility in the electrolyte and the risk of formation of sludge at the bottom of the cell. Several options were considered as regards measures for reducing carbon consumption and dust release, including the use of special additives, introduced into the anode paste during production of anodes: Al₂O₃, Na₂CO₃ and ZnS. The results of the study on how these additives change the reactivity of anodes are presented. Some methods for improving the quality of the produced anode blocks by increasing the degree of impregnation of coke by pitch during anode production are presented; they are realized by means of imparting multi-polar electric charges of coke dust and pitch; reducing the degree of oxidation of the side surface of the anode, achieved with the use of a new anode configuration with a slot on the side surface, and also by increasing the stability of the upper surface of the anode to oxidation by air due to a change in the loading algorithm for the covering material.
This paper was written within the project 02.G25.31.0181 “Development of a super-power energy efficient technology for aluminium RA-550 (РА-550) obtaining” according to the program of realization of complex projects for creation of high-technological production, approved by the governmental order of Russian Federation No. 218 (9 April 2010).

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