School of Nonferrous Metals and Materials Science, Siberian Federal University, Krasnoyarsk, Russia:

T. V. Piskazhova, Professor of the Department for the Automation of Production Processes in Metallurgy, e-mail: piskazhova@ya.ru
T. V. Dontsova, Associate Professor of the Department of Automation of Production Processes in Metallurgy

Energy-Saving Cell’s Designs RUSAL Engineering & Technology Centre, Ltd., Krasnoyarsk, Russia:

Y. R. Shaydulin, Manager of Project, Energy-Saving Cell’s Designs
Y. О. Avdeev, Project Manager

The productivity and current efficiency of aluminum cell depend on several factors, such as current strength and current distribution over the anode and cathode, electrolyte temperature, alumina content in the electrolyte, and the cryolite ratio (CR) and other parameters interacting with each other. The power consumption in operational controlling depends mainly on the anode-cathode distance between the anode base and the metal surface (ID), which is desirable to have as low as possible, but it is important not to cross the border, after which the above process variables will fall into the area of reduced productivity disorders. The important thing in controlling the aluminum cell is to maintain the parameters of the aluminum cell within the target limits established in the technical regulations, and reducing the variations of these parameters allows the process to operate in a stable mode. Modern heat balance controlling of aluminum electrolysis cells should include both algorithms for selecting a given voltage on aluminum cells (this is the control lever for controlling the ID) and algorithms for maintaining technological parameters within specified limits. The article presents a review of methods for studying the thermal balance of aluminum cells, and describes known algorithms and methods for controlling them. An algorithm for the interconnected control of a given voltage and electrolyte composition developed by the authors is given.

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