RUSAL ITTs, Krasnoyarsk, Russia:

V. Yu. Buzunov, Director of the Directorate for Aluminium Production and Development
S. A. Zykov, Manager of the Anode Department, Directorate for Aluminium Production and Development
S. A. Khramenko, Project Leader, Directorate for Aluminium Production and Development, e-mail: sergey.khramenko@rusal.com

Anode paste is a coke-pitch composition. The pitch-coke interaction in mixer determine properties anode paste. The main tasks of mixing are the uniform distribution components of the coke-pitch composition and effective impregnation pitch in coke’s open pores. The degree of pitch impregnation in coke’s pores depends on the properties of coke, pitch and mixing conditions. Interaction between coke and pitch was investigated by the drop spreading method, image analysis and mercury porosimetry. These methods require special instruments and no widely use in industrial conditions. In this article, method for estimating the degree of impregnation of coke by coal tar pitch is discussed. The method uses standard devices for determining the volumetric characteristics of coke and anode paste. Coke’s porosity and the anode mass porosity estimate as ratio vibro-volume density and apparent density of the fraction –2.36+1.18 mm. The degree pitch’s impregnation estimate as ratio the porosity coke and the porosity anode mass. Industrial tests of the method showed its effectiveness and allowed to reveal some features of the industrial process of mixing.

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