Abstract
Mineral value chains, also known as mining complexes, involve mining, processing, stockpiling, waste management and transportation activities. Their optimization is typically partitioned into separate stages, considered sequentially. An integrated stochastic optimization of these stages has been shown to increase the net present value of the related mining projects and operations, reduce risk in meeting production targets, and lead to more robust and coordinated schedules. However, it entails solving a larger and more complex stochastic optimization problem than separately optimizing individual components of a mineral value chain does. To tackle this complex optimization problem, a new matheuristic that integrates components from exact algorithms (relaxation and decomposition), machine learning techniques (reinforcement learning and artificial neural networks), and heuristics (local improvement and randomized search) is proposed. A general mathematical formulation that serves as the basis for the proposed methodology is also introduced, and results of computational experiments are presented.
Similar content being viewed by others
Notes
Note that, in this paper, it is assumed that the recovery factor at the first-stage and intermediate facilities is equal to 1, while it is smaller than 1 in the last-stage facilities. Different values for the recovery factor can be easily accommodated without any added conceptual difficulties.
Note that upper bound on the flow from \(i\) to \(j\) cannot be defined as \(\overline{{Y}_{ij}^{s}}=min\{{\sum }_{g\in {\mathcal{G}}_{i}}{w}_{g}^{s}, \overline{{C}_{i}}, \overline{{C}_{j}}\}\) because the capacity constraints are modelled as soft constraints (cf. constraints (27)–(29)), and thus the flow on arc \((i,j)\) might exceed the facilities’ capacity.
References
Androulakis I, Maranas C, Floudas C (1995) α bb: a global optimization method for general constrained nonconvex problems. J Glob Optim 7:337–363
Benders JF (1962) Partitioning procedures for solving mixed variables programming problems. Numer Math 4(1):238–252
Birge J, Louveaux F (2011) Introduction to stochastic programming, 2nd edn. Springer, New York
Del Castillo MF, Dimitrakopoulos R (2019) Dynamically optimizing the strategic plan of mining complexes under supply uncertainty. Resour Policy 60:83–93
Goodfellow R, Dimitrakopoulos R (2016) Global optimization of open pit mining complexes with uncertainty. Appl Soft Comput 40:292–304
Gupte A, Ahmed S, Dey S, Cheon M (2017) Relaxations and discretizations for the pooling problem. J Glob Optim 7:337–363
Haverly C (1978) Studies of the behavior of recursion for the pooling problem. ACM SIGMAP Bull 25:19–28
Kingma DP, Ba JL (2014) ADAM: a method for stochastic optimization. arXiv:1412.6980
Laporte G, Louveaux FV (1993) The integer L-shaped method for stochastic integer programs with complete recourse. Oper Res Lett 13:133–142
Lamghari A, Dimitrakopoulos R (2012) A diversified tabu search approach for the open-pit mine production scheduling problem with metal uncertainty. Eur J Oper Res 222:642–652
Lamghari A, Dimitrakopoulos R (2020) Hyper-heuristic approaches for strategic mine planning under uncertainty. Comput Oper Res 115:1–18. https://doi.org/10.1016/j.cor.2018.11.010
McCormick G (1976) Computability of global solutions to factorable nonconvex programs: part I—convex underestimating problems. Math Program 10:147–175
Montiel L, Dimitrakopoulos R (2015) Optimizing mining complexes with multiple processing and transportation alternatives: an uncertainty-based approach. Eur J Oper Res 247(1):166–178
Montiel L, Dimitrakopoulos R (2018) Simultaneous stochastic optimization of production scheduling at Twin Creeks mining complex. Nevada Min Eng 70(12):48–56
Montiel L, Dimitrakopoulos R, Kawahata K (2016) Globally optimising open-pit and underground mining operations under geological uncertainty. Min Technol 125(1):2–14
Zhang J, Nault BR, Dimitrakopoulos R (2019) Optimizing a mineral value chain with market uncertainty using benders decomposition. Eur J Oper Res 274(1):227–239
Acknowledgements
The work in this paper was funded by NSERC CRDPJ 411270-10, NSERC Discovery Grant 239019-06, and the industry members of the COSMO Stochastic Mine Planning Laboratory: AngloGold Ashanti, Barrick, BHP, De Beers, Kinross, Newmont, and Vale. This support is gratefully acknowledged. The authors would like to thank two anonymous referees for their valuable comments and suggestions that helped improve the paper.
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Lamghari, A., Dimitrakopoulos, R. & Senécal, R. A matheuristic approach for optimizing mineral value chains under uncertainty. Optim Eng 23, 1139–1164 (2022). https://doi.org/10.1007/s11081-021-09629-9
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11081-021-09629-9