Abstract :
At present stage of the development of the mineral resource complex, a trend is seen to deterioration of geological and engineering conditions of mining ore deposits, which entails increase of losses and dilution of mineral, causing increase of the cost price of mineral production and processing. With consideration of the specified limiting conditions, the maximal net present value of deposit mining will be achieved with minimal economic loss resulted from mineral losses and dilution.
For the conditions of steeply-sloping ore pits, analysis was conducted of the impact of the bench height on the value of mineral losses and dilution, and necessary calculations were made to identify the degree of influence of the pit bench height and the height of the triangle of inmixed waster rocks on the values of losses and dilution by three possible modes of preparing a new horizon (in mining from the hanging wall to the bottom wall, in preparation across the ore body).
According to the results of the research, conclusions were made that the economic loss related to the losses and dilution, increase in direct proportion to the increase of bench heights; the mode of horizon preparation significantly influences the value of losses and dilution and the economic losses related to them; the value of losses and dilution increases with increase of bench height, and the current stripping ratio reduces. For this reason, for determining the optimal bench height, joint consideration of the losses and dilution with the current stripping ratio, is required. The conducted technical and economic calculations result in recommending the bench height in ore zone, equal to 5 m. with maintaining the rock bench height of 20 meters
Keyword :
deposit, mineral dilution, economic loss, bench height, pit, stripping ratio