PSJ Cobre Mendocino has signed a preliminary agreement with Metso Corporation to acquire the processing plant for its future operation in Uspallata, Las Heras Department. The collaboration covers the comprehensive supply of the plant, including equipment for the different processing stages, among them flotation and tailings filtration.
The most significant technical modification is the incorporation of filtration, which will enable a processing capacity of up to 42,000 tonnes of ore per day, while maintaining the previously approved water requirement of 141 l/s, with no changes to the overall layout of the facilities or the area assessed.
By Panorama Minero
The technology reduces the moisture content of the resulting material and increases water recovery for recirculation into the production circuit. The filtered tailings will have a higher solids content, improving their compaction, handling and disposal. Knight Piésold developed the design of the tailings storage facility.
The 141 l/s corresponds to 4.45 hm³ per year, or approximately 12,180 m³ per day. At the plant's maximum capacity, this flow rate represents approximately 0.29 m³ of water per tonne processed.
Fabián Gregorio, President of PSJ Cobre Mendocino, linked Metso's involvement to operational efficiency, optimised water use and “the highest standards in the mining industry”.
Metso's Experience in Copper and Tailings
Finland-based Metso provides crushing, grinding, flotation and filtration technologies, with a presence in approximately 50 countries and around 18,000 professionals.
The current company was formed in 2020 through the combination of Outotec and Metso Minerals, while copper accounts for approximately 40% of sales in its Minerals segment.
Its copper concentrator orders include Barrick's Lumwana project in Zambia, worth approximately €70 million, covering grinding, flotation, thickening, feeding and filtration equipment; Zijin Mining's Julong project in China, with 24 TankCell TC630 flotation cells at an altitude of 5,300 metres; and a new plant in Kazakhstan, worth approximately €85 million.
In Chile, Metso secured a contract to supply equipment ranging from crushing to flotation for Minera Arqueros' greenfield project in Coquimbo.
In tailings filtration, its previous projects include Larox FFP3512 filters for dry stacking at Eldorado Gold's Skouries project in Greece, worth approximately €14 million, and vertical plate filters for Gold Fields' Salares Norte operation in Chile.
The equipment configuration for PSJ will be defined during the contractual stage. In May, Metso also announced an expansion of its operations in Argentina, with a new office and a focus on San Juan.
A Key Technical Decision for the Project
The signing involved Gregorio; Marcelo Avecilla, CEO of PSJ Cobre Mendocino; and Metso representatives, including Fernando Samanez, Vice President of Minerals Sales for South America, and Hannele Vuorimies, Vice President of Global Sales for Solutions.
The agreement brings together three key elements in a single decision: the plant supplier, maximum processing capacity, and PSJ's water and tailings management arrangements.
Although still preliminary, it establishes these decisions within the previously approved water requirements and project footprint, alongside a production forecast that the company has increased compared with the Environmental Impact Report (IIA).
PSJ Cobre Mendocino adds this agreement to the recent appointment of Marcelo Avecilla as CEO, completed in recent weeks.
According to the IIA, the Uspallata copper project envisages a 16-year mine life, total ore feed of 157.261 million tonnes and 653,531 tonnes of contained copper.
Its updated projections anticipate 75,000 tonnes per year of contained copper during the first four years, together with 80,000 ounces of gold and 900,000 ounces of silver, with CAPEX of approximately US$800 million.
This development plan now incorporates a processing plant with capacity of up to 42,000 tonnes per day and a water requirement of 141 l/s, as the company defines its executive leadership and one of the central components of its future operation.
