Mine to Flotation Process Optimization at Chinalco Toromocho Operation Part II

Abstract

Minera Chinalco Peru S.A (Chinalco) has been continuously optimizing its value chain, from the mine to comminution and flotation circuits, to achieve long-term sustainable improvement at the Toromocho mining complex. Hatch Consulting & Technology has provided technical support throughout the project, identifying opportunities for improvement in the entire production chain. Optimization of drill and blast, the Phase I grinding circuit (Line 1) and development of a throughput forecast model were presented previously at Procemin 2023 (as Part I). Following this, the Phase II grinding circuit (Line 2, commissioned later) was optimized along with debottlenecking and optimization of the Cu bulk flotation circuit. These components are presented in this paper (Part II) along with a summary of the outcomes of the integrated Mine-to-Flotation optimization.

The project identified several improvement opportunities, with a potential total (for both grinding circuits) throughput increase of up to 14%. Simulations indicated that for the same concentrate copper grade, this significant increase in throughput could reduce the overall copper recovery by around 1%. Detailed analysis of the flotation circuit identified debottlenecking opportunities to maximize and restore the overall copper recovery while maintaining the concentrate copper grade. These opportunities were ranked as ‘quick-win’ (can be implemented quickly without significant capital costs) and major CAPEX projects. Simulation results show that the ‘quick-win’ opportunities can improve overall copper recovery by approximately 1.5% while maintaining the concentrate copper
grade. Additional recovery improvement could then be achieved via the major CAPEX options. Implementing all grinding and flotation recommendations would provide a significant increase in throughput while maintaining or even increasing copper recovery to establish a robust foundation for long-term operational efficiency and sustainability at Toromocho.