Irkutsk National Research Technical University, Irkutsk, Russia:
V. V. Elshin, Professor, Head of a Chair of Automation of Production Processes
A. P. Mironov, Assistant Professor of a Chair of General Education Subjects
A. E. Ovsyukov, Programmer of a Part-time and Evening Faculty Office, e-mail: a-ovsyukov@rambler.ru

We made an attempt to solve the problem of forming a criterion for optimal control and development of the structure of a control system for autoclave desorption, which is one of the main processes in gold hydrometallurgy. The process is considered in detail from the point of view of management. The analysis of the process is based on the previously developed mathematical model of high-temperature desorption of gold from active carbons. Important parameters that influence the course of the process are identified. The shortcomings of existing solutions for automation of gold desorption from active carbons, such as increased consumption of eluent and electricity, are given. The optimality criterion is formulated as minimization of the total energy expenditure for the process, while maintaining a given level of gold recovery from active carbons. The process kinetics does not depend on the concentration of dissolved gold in the solution. A set of necessary data is required for calculating the process control parameters. There is also a technological scheme that allows implementing the proposed method of process control. The algorithm of process control is presented in the form of a sequence of actions that are required to conduct the process in accordance with the proposed control criterion. The method of calculation of control parameters is specified. The structure of the control system consisting of the following blocks is presented: input of information on the mode parameters, processing of the input information, calculation of the control parameters, output block, input of the expert information, input of the information on laboratory measurements. Advantages of the proposed method are provided before the method for controlling the periodic desorption of the currently used gold, such as: a general reduction in energy consumption, a smaller final eluate volume, a higher average dissolved metal concentration in the eluate, etc.
This work was carried out with the financial support of the project No. 02.G25.31.0075 within the governmental order of the Russian Federation No.218 on 09.04.2010.

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