Metso Supplies SX-EW System for Tia Maria

Metso Corporation has entered into an agreement with Southern Peru Copper Corporation to supply a solvent extraction and electrowinning (SX-EW) system for the Tia Maria copper project in Peru, targeting industrial-scale cathode production.

Context of the Cooperation
Metso Corporation, a supplier of mineral processing technologies, is partnering with Southern Peru Copper Corporation, a major copper producer, to implement hydrometallurgical processing infrastructure at the Tia Maria site in Cocachacra, Arequipa.

The cooperation addresses the requirement to convert copper-bearing leach solutions into market-grade cathodes using a continuous hydrometallurgical process. The scale of the Tia Maria project and the need for integrated process performance across extraction and electrowinning stages necessitate coordinated engineering, equipment delivery, and commissioning support.

Technical Solution and Responsibilities
Metso’s scope covers the design and supply of VSF solvent extraction and electrowinning plants, combining liquid–liquid extraction with electrochemical deposition. In the solvent extraction stage, copper ions are selectively transferred from the aqueous leach solution into an organic phase and then re-extracted into a purified electrolyte. This electrolyte is subsequently processed in electrowinning cells, where copper is deposited onto cathodes under controlled current density and electrolyte conditions.

The system includes electrolyte filtration through dual media filters to maintain solution purity, automated cathode handling using a robotic stripping machine, and an acid mist capture system to control emissions generated during electrowinning. Together, these subsystems are configured to support a production capacity of 120,000 tonnes per year of LME Grade A copper cathodes. Metso is responsible for process engineering, equipment supply, and integration, along with start-up support and spare parts provision.

Deployment and Implementation
The SX-EW plant will be installed at the Tia Maria site in southern Peru. Basic engineering has been completed, enabling progression to detailed engineering, installation, and commissioning phases. The system is designed to integrate with upstream leaching operations and downstream cathode handling infrastructure.

Metso will provide site advisory services through its regional service network, supporting installation, commissioning, and operational ramp-up. This includes process stabilization and alignment of operating parameters with design specifications.

Applications and Use Cases
The deployed solution is intended for copper hydrometallurgy, particularly in operations processing oxide ores or low-grade deposits. By enabling direct cathode production from leach solutions, the SX-EW route eliminates the need for smelting and refining stages. Automation of cathode handling and control of electrolyte quality contribute to process consistency, operational safety, and maintainability in continuous production environments.

Results and Expected Impact
The integrated system is designed to ensure stable electrolyte composition, controlled deposition conditions, and consistent cathode quality. Filtration and emission control systems support operational reliability and environmental compliance.

Performance gains are expected through reduced manual intervention, improved process control, and optimized reagent and energy usage. The standardized integration of solvent extraction and electrowinning stages also facilitates predictable scaling and lifecycle maintenance.

Edited by an industrial journalist Sucithra Mani with AI assistance.

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