Further to Massachusetts Institute of Technology spinout SiTration and global miner BHP's initiative to trial valorisation technology in the historic Globe-Miami mining district of Arizona, the companies have announced two pilot deployments at BHP's Copper Cities site.

Starting this month, SiTration and BHP will validate continuous and autonomous production of copper from legacy mining water over one month using an initial small-scale pilot plant. A larger deployment is planned for later this year to produce up to two tonnes of commercial-scale copper cathodes over a two-month period.

The historic Copper Cities site produced almost 400 000 t of copper between the 1950s and 1980s. Today, SiTration and BHP see an opportunity to recover value from legacy mining assets such as these, with the potential to create new pathways for domestic US copper supply.

Through bench-scale testing using real feedstock from the site, SiTration has already demonstrated London Metal Exchange Grade A copper production without using any chemicals or generating new waste products. Additionally, preliminary tests have yielded energy consumption below 4 kWh/kg to recover copper from the diluted legacy mine water.

SiTration CEO and co-founder Brendan Smith believes the American Southwest region houses billions of dollars' worth of copper in legacy mining water. "With global copper demand projected to grow by 70% by 2050, tapping into these resources is an excellent pathway to bolster domestic supply chains while producing copper at the bottom of the global cost curve."

BHP legacy assets GM Kevin Ramsay adds that the Copper Cities pilot provides an opportunity to evaluate an innovative approach to recover copper from mining-impacted water while generating valuable technical and operational insights. "We are excited to work with SiTration to test this technology under real operating conditions and better understand its potential to recover value from legacy mining water sources."