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The article discusses the topic of the specific power consumption of a drum mill type SAG 8.5x5.3. The purpose of the study is to determine the influence of some basic parameters like angular velocity of the mill drum, the wear on the drum’s lining, mass of the mill filling, loading rate of the mill with ore and flow rate of incoming water of the product to be milled on the relative power consumption of the mill for maintaining quality. To determine the energy consumption of the mill, the listed parameters were measured and a Fisher matrix was constructed. In accordance with the selected target function, energy consumption patterns are synthesised depending on the loading rate of the mill with ore, the mass of the mill filling,the flow rate of the incoming water and the wear on the drum’s lining. Data processing was performed using the STATGRAPHICS computer programme and an adequate model has been found according to the selected target function. The target function has been found to satisfy the conditions for maintaining quality and reducing costs.

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In the current development, the object is the icing of drums of belt conveyors that work in open mines located at high altitudes and in winter conditions. A literature review was made of publications related to the problems at low temperatures and the presence of moisture, including the icing of rollers and drums of belt conveyors. Conceptual options are suggested to prevent freezing and related accidents. The options are accompanied by short methods for determining the main technical parameters. Finally, the advantages and disadvantages of the described options are indicated and, in conclusion, the best among them for the specific working conditions. A stationary or a mobile heater is chosen as a better option.

The determination of the optimal operational mode of drum mills can be assessed by different criteria. The most important of them can be formulated as follows: “To be specified and established the values of the mill operational parameters regarding to which it is possible to be provided the user’s expected performance at the required quality of the final product and the same to be achieved at minimal energy consumption”. For the fulfillment of this condition, there has to be determined the laws of productivity variation, the final product quality and the energy consumption in function of the adequately chosen representative control parameters of the mill. There are obtained mathematical models, describing the most important technological parameters of the machine and are made conclusions about the factors influencing on them.