Mekhanobr Engineering JSC (St. Petersburg, Russia):

Bogdanovich A. V., Research Director, Doctor of Engineering Sciences, science@mekhanobr.spb.ru

On the basis of the extensive experience, covering almost a fiftyyear period of the laboratory research and practical adjustment of processing technologies at concentrating plants, most convenient methods are proposed for the obtained results precision estimation as well as work planning mathematical methods with a view to determine the effects of various factors upon processing regimes and to find optimal regimes. Sharpness of separation is recommended to be estimated on the basis of determination of mean-root-square errors, expressed through absolute or relative values of separation attribute. The method of mean-root-square errors determination by the sum of mutual impurities in separated products, which is definitively related to number of separation curve mean-square deviations, falling between expected-values of separation criterion attributes of separated components, is also convenient. With respect to the mathematical methods of extremal experiment planning, the central rotatable uniform planning method is very economic, convenient and informative. It permits to obtain the equations of second order, reflecting the effects of different factors upon separation processes with assigned precision. The plan procedures of the experiments studying processes depending on 2–5 factors, as well as computation order for coefficients of the equations of second order with 2–5 variable values are presented in the paper. The material expounded in the paper may be used as an advisory tool expediting and simplifying ores separation efficiency estimation.

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