PURGES Pilot Plant: Successfully commissioned and advancing towards full operation

In the last months, CETAQUA proceeded successfully with the  PURGES process, a promising solution for recovering valuable resources from polymetallurgical refinery (PMR) waste from Cobre Las Cruces. This process is central to METALLICO's goal of achieving circularity and sustainable resource management within the European raw materials sector.

The PURGES pilot plant, built by Cetaqua, is configured to operate at a continuous flow rate of 150 litres per hour and is structured around a four-stage treatment stages designed to maximise efficiency and enable the selective recovery of valuable metals, specifically cobalt.

The complete treatment process includes the following connected and sequential stages:

●       Initial pre-treatment based on sulphide precipitation and oxidation: The process begins with a crucial pre-treatment step using sulphide precipitation followed by an oxidation step. This stage is intended to remove interfering metals such as Cu, Zn and Fe.

●       Selective metal recovery via ion exchange (IEX): The core of the separation process is the use of advanced ion exchange resin technology. This stage is highly selective, designed to efficiently capture cobalt from the treated solution.

●       Diffusion dialysis: The IEX stage is followed by a diffusion dialysis phase for the recovery of sulphuric acid, which contributes to the overall circularity of the process and reduces the need for reagents.

●       Final cobalt recovery: The final stage of the pilot treatment focuses on a selective precipitation and crystallization aimed at recovering battery grade cobalt from the remaining solution.

Following the completion of the pilot plant construction, the system has been commissioned over the past few months. This period has included the full integration and initial functional testing of all individual components and sub-systems, as well as the start of the optimisation period. Optimisation is now being carried out in close collaboration with UPC, which performed the lab-scale optimisation of the process.