Mehdi Rahmanpour - School of Mining Engineering, Faculty of Engineering, University of Tehran, Tehran, Iran
Morteza Osanloo - Department of Mining Engineering, Amirkabir University of Technology, Tehran, Iran
S. M. Mahdi Mirabedi - School of Mining Engineering, Faculty of Engineering, University of Tehran, Tehran, Iran

Long-term production planning in open-pit mines is a precedence-constraint knapsack problem. A spatial representation of the mining region (called the block-model) is the primary input of mine planning models. One should note that as the number of blocks and periods to be planned increases, the number of decision variables increases. This paper presents a fast yet straightforward algorithm to reduce binary variables in open-pit mine production planning models. The algorithm considers mining capacity, processing capacity, and pit deepening rate to estimate the time span within which a block is mineable. This paper applies the algorithm in ۱۲ different cases. The number of blocks varies from ۱۰۰۰ to ۲۴۰۰۰۰, and the mining periods range from ۶ to ۳۰ years. According to the results, this algorithm is helpful for problem size reduction.

Production Planning, open-pit mining, Long-term Planning, mining time-span