Delimitation of the Final Pit in Open Pit Mines Using the Pseudoflow Maximum Flow Algorithm: A Comparative Analysis of 1×5 and 1×9 Arcs

Marquina-Araujo J.J.; Cotrina-Teatino M.A.; Mamani-Quispe J.N.; Ccatamayo-Barrios J.H.; Ortiz-Quintanilla S.M.; Antonio-Araujo E.; Castillo-Chung A.R.; Portilla-Rodriguez H.R. · Mathematical Modelling of Engineering Problems (2024) · DOI: 10.18280/mmep.110711

Resumen

The primary aim of this research was to delimitate the final pit in an open pit mine using the 1×5 and 1×9 arch methods of the pseudoflow maximum flow algorithm. To achieve this, Exploratory Data Analysis (EDA), economic, and geomechanical parameters were utilized. Various final pit scenarios were generated by varying the revenue factor. The analysis was conducted using Python 3.11 (Jupyter Notebook) and SGeMS V.3.0 software. The block model comprised 480, 000 blocks, each measuring 10×10×10 meters, with a copper grade range from 0 to 1.41%. Specific parameters were employed, including a slope angle of 45°, a base copper price of 3.90 US$/lb, and smelting, extraction, and crushing-grinding costs of 0.40 US$/lb, 2.30, and 11.00 US$/ton, respectively. Twenty final pits were generated for each method, based on a revenue factor from 0.10 to 2.00. The results indicated that both methods are effective for final pit delineation, with the 1×5 method achieving an NPV of 17, 855 MUS$ and a REM of 0.27, and the 1×9 method attaining an NPV of 18, 456 MUS$ and a REM of 0.35. It was concluded that the 1×9 arch method is preferable as it yields a higher NPV. This study underscores the importance of methodological selection in the planning of open-pit mines, demonstrating that despite a higher REM, the 1×9 method significantly enhances the NPV, implying substantial economic benefits for the industry.

Instituciones: Universidad Nacional de Trujillo; Universidad Nacional de San Cristóbal de Huamanga; Universidad Nacional Jorge Basadre Grohmann; Universidad Privada del Norte