Optimisation of Stockpile Draw-down Capacity Using CAD Software

The accurate determination of the live reclaim for a multi-hopper system is difficult and the optimisation of the feeder spacing time consuming. The use of a high-end CAD package can greatly reduce the time required for the optimisation of hopper spacing. This paper will present the underlying theory and corresponding results from a computer modeling process for two bulk materials. The results of the modelling process show, as expected, that an increase in the height of a stockpile requires an increase in the hopper separation distance to achieve optimal draw-down. In addition, the inclusion of a central feeder requires an increase in the hopper separation over a two feeder arrangement in order to optimise the draw down characteristics. The results obtained to date indicate that for a wide range of material strengths the optimal hopper separation regardless of hopper size lies between approximately 0.6 of the stockpile base radius for a two feeder installation, to approximately 1.2 times the base radius for a three feeder installation. More work is still required in all areas of the analysis of stockpile drawdown performance including the seldom utilised close coupled feeder system.