The extensive testing program carried out during 2021 and 2022 validated the water treatment requirements for the Penco Module flowsheet, thereby satisfying the objective to minimize the freshwater requirements of the process plant through maximizing the recycling of the process liquids within the plant. During this program, an innovative process was conceived, which allows the recycling of water in a closed circuit to meet the goal of zero liquid discharge. As a result, the production flowsheet shows that 95% of the water used by the process plant is retained within the circuit, that 99% of the main reagent (ammonium sulphate) is recirculated, and that no liquid residues will be produced, thus negating the need for a tailings storage facility.

The process flowsheet has two patents in place that protect this innovation. The first has already been granted in all the countries that were requested: Chile, Brazil, US, and China, and the second patent has recently been filed and received in Chile, and it is pending to be granted in China, Brazil and Australia.