RSE Sign Contract to Deliver Innovative Pilot Lithium Extraction Plant

All News

RSE are proud to announce today that we have been selected to provide engineering, procurement, construction and commissioning (EPCC) support for GeoCubed’s innovative lithium extraction pilot plant. The project will be delivered in collaboration with RSE Group companies Sheers, Saftronics and TCS.

GeoCubed is a collaboration between Cornish Lithium, the innovative minerals extraction company and GEL (Geothermal Engineering Limited), the developer of the United Downs Geothermal Power Project, established to design, procure and build a pilot plant to trial Direct Lithium Extraction (DLE) technology to extract lithium from the geothermal waters, which circulate naturally at depth in the granite rock that underlies Cornwall. The £4.0 million Pilot Plant is being supported by the Cornwall and Isles of Scilly Local Enterprise Partnership (“LEP”) with £2.9 million from the UK Government’s Getting Building Fund.

DLE Technology Module

RSE can also announce that the DLE technology module, provided by GeoLith, has now arrived at our site in Darlington, UK and we are now integrating the DLE module into the pilot plant ahead of its delivery to the United Downs Geothermal Testing Facility, where the pilot plant will be commissioned by the end of March 2022.

Deep Geothermal Assay Results Confirm Expected Lithium Concentrations

In August 2021 Cornish Lithium and GeoCubed worked together to collect a bulk sample of geothermal water during the Electrical Submersible Pump test conducted by Geothermal Engineering Limited (“GEL”) at its United Downs Deep Geothermal Project (“UDDGP”). The fluid collected will primarily be used to feed the Pilot Plant for the purposes of evaluating DLE technologies.

Lithium concentrations averaged 263 mg/l over 63-hours of pumping, with a maximum grade of 296 mg/l recorded. These concentrations were in line with those obtained from an airlift test in August 2020.

In addition to the encouraging lithium concentrations, other key by-products such as caesium, rubidium and potassium were shown to be at elevated levels. Importantly deleterious elements, which can negatively impact the processing of waters through DLE technologies and the quality of the final lithium product, were exceptionally low. Magnesium levels were below 5 mg/l, transition metals such as iron were shown to be negligible, and silicon concentrations were low.

RSE are really excited by the opportunity to continue our collaborative working relationship with the GeoCubed team in the next development stage of this new innovative Lithium production process. We pride ourselves in being a business at the forefront of embracing new technologies which support the sustainable and secure growth of the UK economy.

We are pleased to announce the appointment of RSE as EPCC contractor. The GeoCubed team has established a strong relationship with the team at RSE and we look forward to working with them to successfully deliver this Pilot Plant, which will provide vital operational data to inform and enable the construction of a commercial scale plant. This will place Cornwall at the forefront of lithium production, as the UK strives to secure a domestic supply of this critical battery metal.

It was also reassuring to see that the assay results from the Deep Geothermal Water samples confirmed the lithium concentrations observed in earlier test work. The continued low levels of deleterious elements is also good news and will be beneficial as we utilise the Pilot Plant to establish the most appropriate processing technologies for Cornish geothermal waters.

This is another step forward towards the establishment of geothermal lithium extraction in Cornwall. We look forward to seeing the results of this next stage of the project as we move forward towards full scale, commercial Direct Lithium Extraction.

We share the ambition for Cornwall to lead the domestic production of lithium as part of the UK’s energy transition. The LEP has committed £2.9 million of Getting Building Fund investment towards the pilot plant and we look forward to seeing it commissioned in the next few months.