Author 1:
Name & Surname: Tikhonov N. O.
Company: RIVS Science and Production Association (Saint-Petersburg, Russia)
Work Position: Head of subdivision
Contacts: e-mail: rivs@rivs.ru

Author 2:
Name & Surname: Gospodarikov A. P.
Company: National Mineral Resources University (University of Mines) (Saint-Petersburg, Russia)
Work Position: Vice-Principal, Professor
Scientific Degree: Doctor of Engineering Sciences

The article presents mathematical framework of a method used by RIVS to forecast energy input of various-type drum mills (ball mills, autogenous and semi-autogenous grinding mills). The basics of the described method were developed by S. Morrel, an Australian expert in mineral material milling, and have not been published previously in Russia. The RIVS experts have compared the new method and a few commonly used techniques and matched the forecasting values against the factual capacities of the on-site mills. As a consequence, it is concluded that the method described in this article yields the most accurate outcome due to the detailed accounting of ball charge motion. The Introduction gives a description of the proposed approximation of ball charge position in a rotating drum and its dependence on the mill velocity. In what follows, the mathematical apparatus used for the forecasting calculation of capacities of the drum shell and cone is presented. The mathematical procedure is based on the calculation of the overall potential and kinetic energy of the ball charge during its motion inside the rotating mill. The concluding section of the article offers empirical formulas to calculate idling and aggregate capacity of the mill main drive.

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