Long-term open pit mine production scheduling with variable cut off grade for cost optimization


Selection of cut off grade in long-term open pit mine planning is a tough research challenge now-a-days. The subsequent operational planning for the selected cut off grade decides the economic factor in mine production
scheduling. The distribution of grade, sequence of mining operation, economic parameters, the capacities of mining operations are influencing points for deciding the model. In any given period of time the dynamic cut off grade is a
function of the availability of ore and the capacity of stockpile as well as the process plant. The extraction sequence and cut off grade strategy should be considered simultaneously in order to achieve the optimum result. By keeping these points in first row, various attempts have been made to develop an electronic technique for the extraction sequence of open pit mines. Because of the numerous variables involved for getting the optimum result, different approaches have been made is not sufficient to widespread acceptance. A new model has therefore been proposed to overcome this shortcoming. The optimum sequences of extraction in each period are recognized by optimum processing decisions. To examine the applicability of the model developed, a case study is offered to validate.

Keywords: NPV, production scheduling, economic loss, mining sequence, cut off grade

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