Cobre’s Ngami Project Achieves 86% Copper Extraction Efficiency in Bench Tests
Cobre Limited has demonstrated the technical viability of its integrated In-Situ Copper Recovery process at the Ngami Copper Project, producing high-quality copper cathode in bench-scale tests. This milestone paves the way for pilot studies and environmental permitting.
- Bench-scale SX-EW test achieved 85-86% copper extraction efficiency
- Electrowinning produced copper cathode at ~97% current efficiency
- Long-term leaching tests showed up to 82% copper extraction from drill core
- Technical viability of integrating SX-EW with ISCR confirmed
- Next steps include environmental permitting and pilot scale testing
Bench-Scale Success at Ngami Copper Project
Cobre Limited (ASX, CBE) has announced a significant technical milestone at its Ngami Copper Project (NCP) in Botswana, successfully producing copper cathode through bench-scale In-Situ Copper Recovery (ISCR) solvent extraction and electrowinning (SX-EW) test work. This achievement confirms the feasibility of the integrated SX-EW process as a downstream recovery method for copper extracted from the insitu wellfield.
The continuous solvent extraction circuit operated stably for approximately 44 hours, achieving peak copper extraction efficiencies of 85-86%. The electrowinning circuit then produced a high-quality copper cathode with a current efficiency of around 97%, characterized by smooth and adherent electrodeposition. These results demonstrate strong circuit performance and validate the technical approach underpinning Cobre’s ISCR strategy.
Long-Term Leaching Insights and Mineralisation Context
Complementing the SX-EW tests, long-term vessel leaching experiments on representative drill core samples yielded copper extraction rates as high as 82%, notably from sample NCP20A. These tests, designed to simulate the insitu environment without crushing the core, provide confidence in the leaching behaviour and support the operating parameters for future ISCR development.
The mineralisation at NCP is sedimentary-hosted and structurally controlled, dominated by fine-grained chalcocite associated with fracture zones, conditions favorable for ISCR. The project’s geological setting near the northern margin of the Kalahari Copper Belt shares similarities with large-scale deposits such as Taseko Mines’ Florence Copper and Copper Fox’s Van Dyke, underscoring the potential scale of the resource.
Path Forward, Environmental Permitting and Pilot Testing
With bench-scale technical viability established, Cobre is now focused on securing environmental permits, a critical step before commencing pilot-scale ISCR testing at the Comet Target within NCP. The company has engaged Loci Environmental to lead the Environmental Impact Assessment (EIA) process and plans additional hydrogeological studies to assess fracture zone continuity, essential for scaling up the ISCR operation.
Economic assessments will be updated to incorporate the SX-EW operating parameters, providing a clearer picture of the commercial viability of full-scale ISCR application. The positive metallurgical outcomes and ongoing exploration results position Cobre well as it advances towards pilot operations and eventual production.
CEO Adam Wooldridge emphasized the importance of this phase, stating that the bench testing supports the viability of a large-scale SX-EW process at NCP, with environmental permitting as the next key milestone. Principal Consulting Engineer Damian Connelly highlighted the absence of technical risks in producing LME-grade cathode copper, reinforcing confidence in the project’s progression.
Bottom Line?
Cobre’s successful bench-scale tests mark a pivotal step, but pilot scale validation and permitting remain critical hurdles ahead.
Questions in the middle?
- How will pilot-scale SX-EW testing compare to bench-scale performance in terms of efficiency and cost?
- What is the timeline and likelihood for securing environmental permits to advance the pilot study?
- How will updated economic assessments impact the project’s feasibility and funding requirements?
