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Hydroprocess 2019 was jointly organized by the University of British Columbia, the University of Antofagasta, and the Chilean company, Gecamin.

The 11th International Seminar on Hydrometallurgical Processes, referred to as Hydroprocess 2019, was held from the 19 to the 21 of June at the Hotel Sheraton in the city of Santiago. It addressed principal innovations in hydrometallurgical processes for metals and nonmetals mining.

With close to 300 attendees and more than 70 technical speakers, the 2019 edition of the seminar spoke about the processes and challenges that arise in hydrometallurgy within the mining industry, making reference to developing new materials and technologies along with optimizing operations.

Eduardo Hasan Soto, Metallurgy Superintendent at Minera Tres Valles, was one of the 27 presenters who belongs to a mining operation that formed part of the Hydroprocess seminar. It was an opportunity to show the audience the scope of his research on “Copper Leaching from Sulfide Ore in Acidic-Chloride Media”, which highlighted the addition of salt to the copper extraction process.

Leaching in chloride media is a project that has been developed since 2015 by the Research and Development team at Minera Tres Valles. It has optimized the production process by decreasing sulfuric acid consumption and increasing copper recovery while shortening the reaction kinetic cycle. The salt leach project is currently in its implementation stage, which requires various reconditioning procedures in the agglomeration, solvent extraction and electro-obtention processes.

Minera Tres Valles has been one of the first companies to bet on developing the process of leaching with chloride media to extract copper. Its experienced research team and up-to-date facilities have made it become an important source of innovation for the Chilean mining industry, being a recurring destination for other companies that are in the planning stage of adding sodium chloride to their production process.

For Eduardo Hasan, “implementing this technology has positioned Tres Valles as a type of role model in the area of leaching copper sulfides by using sodium chloride as an oxidizing agent. Although sodium chloride leaching has research dating back from the 1990s, today there are only three companies that are in some stage of implementing this technology, Minera Tres Valles being one of them.

The merit of Tres Valles’ project stems from having developed this technological innovation with modest resources in comparison to large-scale mining companies (the project cost at BHP’s Spence mine was US$ 220 MM; the estimated cost of Minera Zaldívar is US$ 170 MM; while the cost of our project is valued at only US$ 7 MM). Additionally, all of our pilot and semi-industrial studies have been carried out by our own staff, forming a “know how” of interest to other medium-scale mining companies.