Optimizing Productive Time in Mining Cycles by Changing Explosives: A Value Stream Mapping Study in Horizontal Excavations

Abstract

This study addresses the optimization of the mining cycle at the Esmeralda mine by changing explosives, with the objective of reducing over-excavation and improving operational efficiency. To this end, the value stream mapping (VSM) methodology was applied to identify inefficiencies in the current mining cycle. Methodological procedures included detailed measurements and data analysis, which revealed that overexcavation was one of the main sources of inefficiency, with an initial percentage of 32%. By implementing the proposal to change the Ammonium Nitrate and Fuel Oil (ANFO) explosive for pumpable emulsion, it was possible to reduce over-excavation to 18%, significantly improving operational times: the total cycle time (TCT) was reduced from 22.1 hours to 19.26 hours, the productive time (TP) decreased from 13.22 hours to 11.28 hours, contributory time (TC) decreased from 4.53 hours to 4.00 hours, and non-contributory time (TNC) was reduced from 5.11 hours to 3.16 hours. These results reflect a more efficient and safer mining cycle, with a notable increase in productivity and a significant reduction in operating costs.