A. Baikov Institute of Metallurgy and Materials Science, Moscow, Russia:

B. G. Balmaev, Leading Researcher (Laboratory of Physical Chemistry and Technology of Aluminium), e-mail: 3.boris@gmail.com

National University of Science and Technology MISiS, Moscow, Russia:
S. S. Kirov, Assistant Professor (Chair of Non-Ferrous Metals and Gold), e-mail: kirovss@list.ru
M. A. Ivanov, Post-Graduate Student (Chair of Non-Ferrous Metals and Gold), e-mail: ivanov@misis.ru
V. I. Pak, Post-Graduate Student (Chair of Non-Ferrous Metals and Gold), e-mail: pakvi@misis.ru

Our article describes the process of filtration of aluminum-bearing hydrochloric acid pulp after kaolin clay leaching with hydrochloric acid. A complex probabilistic and deterministic model of the filtration process is constructed taking into account the influence of the leaching factors of kaolin clay. The productivity and rate of filtration were studied, depending on hydrodynamic and physicochemical factors. We found the particular dependences of the filtering efficiency from process temperature (Y1), material size (Y2), polyacrylimide amount (Y3) and acidity factor (Y4). The system temperature and polydispersity make a biggest effect on hydrochloric acid pulp filtering. The mathematical model of the filtering process, obtained after the correction of the Protodyakonov equation by the Rayleigh distribution, was used to optimize and predict the process. By changing the initial conditions of kaolin clay leaching, it is possible to predict the performance of the filtration process outside the studied interval, where the experimental verification is economically inexpedient. The best filtration conditions for hydrochloric acid pulps obtained after kaolin clay leaching are: temperature — 70 ^oС, material size (residue on sieve 008) — 10%, polyacrylimide amount — 30 mg/l, acidity index — 1.3. Calculations, carried out with the model, defined that, using these parameters, the filtration productivity reaches a maximum value of 205.9 kg/(m²·h), and the experimental result using these conditions is 200.3 kg/(m²·h).
This work was carried out with the financial support from the Ministry of Education and Science of Russian Federation within the fulfillment of the subsidiary agreement on 02 November 2015 No. 14.581.21.0019 (unique identifier: RFMEFI58115X0019).

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