St. Petersburg State Mining University (St. Petersburg, Russia):

R. Yu. Feshchenko, Cand. Eng., Assistant of the Chair of Automation of Technological Processes and Production, e-mail: feshchenko.r.yu@mail.com
O. O. Erokhina, Bachelor
D. S. Lutskiy, Cand. Eng., Associate Prof. Of the Chair of General and Physical Chemistry
V. V. Vasilyev, Cand. Eng., Assistant of the Chair of Metallurgy

Scientific and Technological Center of “Energoprom” (Moscow, Russia):

A. L. Kvanin, Cand. Phys.-Math., Head of Scientific-Technical Projects

Increase of the part of graphitized cathode blocks used in the modern assemblies for production of primary aluminium via electrolytic method is recognized as the main direction of development of this technology. These blocks have a row of indisputable advantages, first of all low electric resistance and high level of electric conductivity. Increased abrasive hearth wear by alumina precipitants during melt motion seems to be the most important problem in operation of such blocks. This wear leads to decrease of service life of an electrolyzer and to increase of cost of manufactured metal. The leading global producers conduct complex works directed on quality improvement of graphitized blocks. These works include a row of scientific directions: rational selection of raw materials, selection of optimal parameters of the technological process, different variants of impregnations etc. Most of researchers agree that rise of density leads to lowering of abrasive wear, and that this effect can be achieved via different ways (first of all by pitch impregnation). Several technical solutions (e.g. creation of variable electric resistance along block length, with lower value close to edges, in the areas with increased wear) have peen confirmed via production testing and are used now successfully at a row of metallurgical works. In Russia graphitized blocks are not used practically. The project of Boguchansky aluminium works (planned to be put into operation in 2016) uses the blocks manufactured on the base of electrocalcinated anthracite with addition of 30 % graphite. Despite of the power engineering potential of Siberian region, such approach is inexpedient, taking into account the fact that high power expenses caused closure of a row of aluminium works in the European part of Russia. Accumulated global experience can be the base for development of science-intensive solutions in the Russian electrode industry and their consequent putting into operation, what in its turn will allow to achieve correspondence between quality of manufactured commercial products and requirements of customers.

The work has been carried out under financial support at the expense of the Educational Grant of the President of Russian Federation for young scientists and post-graduates, realizing prospective scientific researches and developments in the priority directions of modernization of Russian economics.

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