Copper and gold mines in Antofagasta, Chile, will soon benefit from a desalination plant built by US-based Severn Trent Services.

The 634,000-gpd plant will use ultrafiltration and reverse osmosis systems to treat seawater drawn from the Pacific Ocean.

Seawater will be pumped to the mine, where 5% of seawater will be processed to obtain pure water.

The plant will be equipped with two Severn Trent Services UAT 705,000-gpd UF trains using DOW UF membranes and two Severn Trent Services UAT 634,000-gpd RO trains using DOW FILMTEC 16-in membranes.

The UF pre-treatment system will operate at 90% recovery, while the single-pass RO system will operate at 45% recovery, to produce water quality below 400ppm total dissolved solids, the company said.

Commissioned by Santiago-based Proequipos, the plant is owned jointly by Antofagasta of London, with a 70% stake, and Marubeni Corporation of Tokyo, with a stake of 30%.

Construction of the plant is expected to be completed in the fourth quarter of 2010.