Siberian Federal University, Krasnoyarsk, Russia:

A. S. Yasinskiy, Post-Graduate Student, e-mail: ayasinskiykrsk@gmail.com
A. A. Vlasov, Assistant Professor of a Chair of Engineering Bachelor's Program CDIO
P. V. Polyakov, Professor-Consultant of a Chair of Metallurgy of Non-Ferrous Metals
I. V. Solopov, Post-Graduate Student

The laboratory experiments of aluminium reduction in high temperature alumina slurry with inert anodes and low melting electrolyte are presented. There is found the information about the impact of alumina partial density in slurry (solids content) on electrical conductivity, voltage, hydrodynamic resistance and bubbles shape and volume during electrolysis. When alumina partial density (and hydrodynamic resistance) increases, convective mass transfer is expected to become difficult, back reaction rate decreases on the one hand, and electrical conductivity increases due to nonconductive phase (bubbles and alumina particles) volume increasing on the other. Laboratory experiments show the problems in high-temperature slurry electrolysis technology: difficult oxygen evacuation from anode space, uneven alumina partial density distribution in areas of sedimentation and fluid flows. High bubbles volume and electrical resistance around 0.125 ohm·m at i_a = 3 kA/m² appears at alumina partial density of 0.81·10³ kg/m³, which corresponds to 25% vol. of alumina in slurry. The ways of resistance decreasing and the technological parameters of high-temperature slurry electrolysis improving are developed. Studying of slurries is important in order to understand their impact on spikes formation.
The paper was written using the results, taken during the project 02.G25.31.0181 “Development of high performance energy saving aluminium reduction technology RA-550” implementation as a part of complex projects realization program of high efficiency production development, approved by Russian Federation government regulation No. 218 from April the 9^th, 2010.

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