RIVS Science and Production Association:

Skarin O. I., Senior Researcher, Candidate of Engineering Sciences

JV “IVS”:

Tikhonov N. O., Head of Subdivision

E-mail (common): rivs@rivs.ru

Optimization of ore pretreatment and selection of the appropriate equipment is one of the main areas of activity of RIVS Science and Production Association. For sizing ore pretreatment equipment, RIVS uses an integration of methods, including conventional commercial and semicommercial testing, and increasingly broadening laboratory testing of ore strength properties. Scale-up of the laboratory test data for the full-sized equipment is based upon mathematical modeling. This article describes the method offered by Barratt for sizing circuit power requirements for autogenous and semiautogenous milling. The method is widely used by RIVS in extended calculations at early design stages. The article is composed of sections successively informing on the existing techniques of sizing SAG mill power, Bond work indexes and their applicability to calculating autogenous/semiautogenous mills. Finally, the authors give a comparative analysis of the results obtained using the described method and in the joint commercial tests conducted by RIVS and SIBIR-Polymetals, Ural Mining and Metallurgical Company. Decision-making on selection of SAG mills increasingly uses the methods of sizing the milling power based on laboratory tests on grindability of minerals. This article considers one of such methods allowing determination of mill characteristics based on the Bond work indexes of crushing, rod milling and ball milling. The authors exemplify the described method application and compare the obtained estimates with the factual field test data. 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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