Por: Edwin Cereceda Espinoza y Jonathan Huamán Reyes, Sociedad Minera El Brocal.

Abstract

Underground mining currently faces ongoing challenges related to safety, productivity, and operational efficiency. In response, the implementation of centralized blasting has emerged as an innovative solution to significantly improve these key aspects. This project, successfully implemented at Sociedad Minera El Brocal, has delivered tangible results and substantial economic benefits through the incorporation of advanced technology and a new operational methodology.

The project began one year ago, driven by the need to reduce personnel exposure to risks associated with explosives handling, increase productivity, and improve ore fragmentation, positively impacting operating costs and overall efficiency. 

Prior to implementation, the traditional process involved hours of direct exposure to explosives during blasting procedures, leading to frequent incidents and variability in productivity due to manual processes and personnel-dependent evaluation times. The proposed solution consisted of implementing a centralized, remote electronic detonation system, allowing blasting operations to be controlled and monitored from a safe location. 

This system was further enhanced through the integration of blast design software for drill patterns and charging schemes, enabling pre-blast simulations and precise adjustment of operational parameters. As a result, ore fragmentation was optimized and the P80 value, i.e., the average size of fragmented material, was significantly reduced.

The transition to the new system was not without challenges, particularly the need for intensive training and a profound change in operational culture. Workers shifted from manual ignition procedures, personnel withdrawal, and sentry positioning to having the entire blasting protocol managed directly from a central station, significantly strengthening operational discipline. As a result, direct personnel exposure was reduced from three hours per day to just thirty minutes, representing an 85% reduction in operational risks.

Operational and economic results were outstanding. Operational discipline improved, with protocol compliance increasing from 75% to 98%. Blasting time was reduced from 60 to 15 minutes, enabling an increase in production from 5,900 to 6,150 tonnes per day, representing a 5% improvement. Effective long-hole drilling hours also increased from 6.2 to 6.8 hours, and drilling equipment productivity improved from 2 to 3 faces drilled per shift.

These improvements resulted in significant cost savings, including a 12% reduction in explosive consumption, equivalent to approximately US$ 250,000, and an increase of US$ 6 million in annual revenue due to higher production.

The reduction in operational incidents also generated savings in accident-related costs, estimated at approximately US$ 20,000 per year. These results have established the project as a benchmark in underground mining, clearly demonstrating how safety and efficiency can be effectively integrated.