Australian Vanadium Limited (ASX: AVL) has announced an encouraging update on the metallurgical testwork currently underway for The Australian Vanadium Project in Western Australia.
The company reported that High Purity 99.4% Vanadium Pentoxide (V2O5) was produced from pre-pilot testwork, with product quality comparable to standard products from existing global producers.
AVL said that the positive benchscale testwork achieved target V2O5 flake product quality and exceptional roast leach vanadium extraction.
The company noted that the bench scale optimisation tests indicated a significant improvement in vanadium roast leach extraction compared to the basis applied in the PFS.
AVL reported that pilot scale testwork is advancing.
Australian Vanadium Project
The Australian Vanadium Project consists of a high-grade V-Ti-Fe deposit located in the Murchison Province approximately 43kms south of the mining town of Meekatharra in Western Australia and 740km north-east of Perth.
The Project consists of 11 tenements covering approximately 260 sq km and is held 100% by Australian Vanadium Limited and has a total Mineral Resource of 183.6Mt at 0.76% vanadium pentoxide (V2O5).
Benchscale testwork program
AVL had recently undertaken a benchscale metallurgical testwork program to optimise the refinery flowsheet for the Australian Vanadium Project.
The company reported that the bench scale optimisation tests indicated a significant improvement in vanadium roast leach extraction compared to the basis applied in the PFS.
Improved vanadium recovery
AVL said that in addition to the standard AVL process, an alternative vanadium production route known as APV (ammonium polyvanadate) was also tested on the leachate produced by roasting and generated a final product quality of 99.4% V2O5, which was independently verified by an accredited laboratory.
The company said that roasting tests were performed on magnetic concentrate that had been pelletised using a binder.
AVL reported that roasting at optimised temperature and reagent conditions resulted in a vanadium roast leach extraction of 94%, a substantial increase from 88% without pelletising. This compares with the roast vanadium extraction of 87.9% applied in the PFS.
It may be noted that the PFS adopted an 80.4% LOM average vanadium recovery for the refinery circuit.
The company noted that the latest roast-leach process testing demonstrates the dual benefits of pelletising and increased roasting temperatures.
AVL said that the optimisation bench scale testing indicates higher vanadium roast leach extraction than adopted for the PFS.
Modifications planned
AVL said that the results have identified improvements to the Pre-Feasibility Study (PFS) design and show that higher vanadium recoveries and lower reagent usage can be anticipated in the planned pilot scale testing which will be used to support the finalised DFS design.
AVL said that it is currently modifying the refinery pilot testwork scope of work to incorporate the learnings from the benchscale.
The company said that the AVL mine standard product is expected to be of outstanding quality by selection of the APV precipitation process.
AVL expressed confidence that this change to the PFS flowsheet has potential to simplify the refinery circuit and lower both capital and operating costs.
What’s next?
AVL reported that the pilot testwork program is advancing as planned. The Crushing Milling and Beneficiation (CMB) circuit continuous testing on 1 x 4 tonne and 2 x 10 tonne typical mine life material blends is due for completion in early July 2019.
The company said that a full refinery circuit vanadium balance and therefore vanadium recovery, will be developed from the pilot testwork program in Q3 and Q4, 2019.
Management comments
AVL’s Managing Director Vincent Algar said, “With the first production of a producer-peer comparable high-purity product and the significant process improvements identified, our confidence increases further as we continue to improve and derisk the project with each step forward.
AVL’s aim is to become the world’s lowest cost vanadium producer and our team is achieving regular breakthoughs to bring the costs down and further improve the project economics. We have a strong focus on seeking to understand our unique mineralisation in detail through the analysis of historical and current drilling programs, test work and studies.
Only by having a thorough understanding of the deposit and process we’re working with, will we have the greatest chance of success throughout the mine’s life. Having a project design which achieves such a high quality standard product using proven technology, further demonstrates the strength of the Company’s processing design and reflects on the quality of our technical team at AVL.”