Anax Metals has confirmed the success of its scaled-up bioleaching technology, achieving copper recoveries of up to 80% and zinc recoveries exceeding 90%, reinforcing its strategic position in Pilbara's base metals sector.
- Scaled-up bacterial column tests yield 77-80% copper extraction
- Zinc recovery surpasses 90%, opening zinc sulphate production opportunities
- Bioleaching technology developed over four years with CSIRO collaboration
- Existing Whim Creek heap leach infrastructure ready for immediate bioleaching restart
- Technology applicable to broader Pilbara ores under regional processing hub plan
Bioleaching Breakthrough at Whim Creek
Anax Metals Limited (ASX: ANX) has announced a significant milestone in its bioleaching technology development, confirming copper extraction rates between 77% and 80% and zinc extraction rates exceeding 90% in scaled-up bacterial column tests. These results, achieved in collaboration with Australia's CSIRO Mineral Resources Research Unit, validate previous smaller-scale findings and underscore the potential for enhanced metal recovery from primary chalcopyrite ores at the Whim Creek project.
Heap leaching of primary copper sulphide ores has long been a challenging frontier due to passivation effects limiting copper recovery. Anax’s success in overcoming these hurdles positions it alongside global copper majors who are actively pursuing breakthrough heap leach technologies to unlock value from lower-grade and stockpiled ores.
Strategic Advantages and Infrastructure Readiness
One of the compelling aspects of Anax’s approach is its integration with existing heap leach infrastructure at Whim Creek, much of which has been refurbished and is permitted for immediate recommencement. The minimal additional capital expenditure required to adapt this infrastructure to bioleaching processes offers a cost-effective pathway to scale production.
In addition, the company’s proprietary flowsheet, combining ore sorting, flotation, and bioleaching, maximizes production capacity and provides operational flexibility. The ore sorting process generates multiple product streams, enabling high-grade concentrates for flotation and lower-grade 'middlings' for bioleaching, thereby optimizing metal recovery and resource utilization.
Zinc Recovery and New Business Opportunities
Beyond copper, the bioleaching tests have delivered zinc recoveries exceeding 90%, surpassing initial expectations. This opens the door for Anax to explore downstream production of zinc sulphate, a potentially lucrative new business avenue. The company is actively advancing studies to establish partnerships and offtake agreements in this area, signaling a strategic diversification of its revenue streams.
Broader Implications for the Pilbara Region
The bioleaching intellectual property developed by Anax is not limited to Whim Creek ores. It is a cornerstone of the company’s Pilbara Regional Processing Hub (PPH) concept, which aims to consolidate and process base metal assets across the region. Planned test work in 2025 will focus on confirming bioleach amenability of ores from other projects, including Develop Global Limited’s Sulphur Springs and Greentech Metals’ Whundo Project, potentially expanding the technology’s application and commercial impact.
Next Steps and Market Context
Anax plans to continue de-risking the bioleaching process through further test work with CSIRO, complete scoping engineering studies, and advance zinc sulphate business development. This progress comes amid a global race among copper producers to develop viable heap leach technologies for primary sulphide ores, driven by the need to exploit lower-grade resources efficiently and cost-effectively.
With its demonstrated technical success and strategic infrastructure advantages, Anax Metals is well positioned to capitalize on these industry trends, potentially reshaping base metals processing in the Pilbara.
Bottom Line?
Anax’s bioleaching success could redefine Pilbara’s base metals landscape, but scaling and commercialisation remain key hurdles ahead.
Questions in the middle?
- How will Anax’s bioleaching process perform at full commercial scale beyond column tests?
- What are the projected capital and operating costs for bioleaching implementation at Whim Creek?
- How quickly can Anax secure offtake agreements and partnerships for zinc sulphate production?