KEY POINTS
• High purity 99.4% vanadium pentoxide (V2O5) produced from representative leach
liquor.
• The vanadium flake product from the Australian Vanadium Project is expected to be
of outstanding quality, comparable to high purity products from existing global
producers.
• Testing has included APV and AMV production routes, allowing optionality in the BFS to simplify the refinery circuit and potentially lower both capital and operating costs.
• Testwork demonstrates ability to produce high purity V2O5 at scale.
Australian Vanadium Limited (ASX: AVL, “the Company” or “AVL”) is pleased to announce an update on the metallurgical testwork to support the vanadium purification flowsheet for the
Australian Vanadium Project (“the Project”). This includes the production of high purity vanadium pentoxide using hydrometallurgical methods, tested as part of the detailed flowsheet validation program undertaken by the Company and its consultants since the 2018 Pre-Feasibility Study (PFS)
1 and following up successfully on previous vanadium pentoxide results2 .
Managing Director Vincent Algar commented, “Test results have shown that the AVL process, using standard methods, has the capability to achieve high purity V2O5 throughout the life of mine. This high purity product is comparable with the high purity vanadium products made by our established producer peers. This outcome comes from concentrating on thorough technical study work and using the process method improvements AVL has identified in that study work. Without
doubt, this quality outcome further increases confidence in the Project.”
Metallurgical Testwork Summary
A metallurgical testwork program is underway to optimise the final stages of the vanadium refining process, which includes precipitation and V2O5 production.
All vanadium purification tests reported in this update have been performed on leach solution derived from roasted material produced in pilot scale testwork at Metso Outotec’s Dansville pyrometallurgical facility in the USA. The concentrates provided to Metso were in turn generated from pilot scale crushing, milling, and beneficiation testwork at ALS laboratories in Balcatta, WA.
Feed materials to the pilot program at ALS were made up from a blend of drill core designed to represent the average first five years and life of mine process feed. The standard refining technique used in the production of vanadium pentoxide produces an intermediary chemical product called AMV (ammonium metavanadate), which was the basis of the PFS refinery flowsheet. This process includes a desilication stage (aluminosilicate precipitation and solid liquid separation) prior to precipitation of AMV at slightly basic pH. In parallel with AMV testwork on representative leach liquor, AVL has tested an alternative mature vanadium production route known as APV (ammonium polyvanadate). The APV  rocessing path is a direct precipitation and operates at lower pH and higher temperature. The APV testing indicates an improved vanadium recovery, a reduced ammonium sulphate reagent consumption and has generated a final product quality of 99.4% V2O5, which was independently verified by an accredited laboratory.
These encouraging results and further APV optimisation testwork currently underway will be used to assess and determine the final purification flowsheet and support AVL’s vanadium product/s specification. Following the refinery pilot testwork program, larger leachate samples will become available to evaluate further V2O5 purification, targeting products to service the vanadium redox flow battery and specialty chemical markets. AVL is the recipient of a federal CRC-P Grant to investigate the production of high purity vanadium. Comparison to Existing Producer Product Specifications There are currently only three primary vanadium mines known to be operating outside China, producing V2O5 from titanomagnetites similar in nature and grade to AVL’s Project. The recent testwork summarised in this report indicates the ability for AVL to produce similar vanadium product specifications to existing producers.
BFS Progress
The metallurgical testwork programs that will be used to underpin the BFS processing flowsheets are nearing completion. Significant pilot scale testing has been completed to validate an optimised concentrator flowsheet and a pelletisation and grate kiln roasting circuit for the front part of the refinery flowsheet. Further leach and vanadium purification testwork is underway to optimise the downstream refinery flowsheet and this is forecast to be completed by the end of year. AVL’s engineering consultant (Wood Mining and Metals) is in the process of updating the process design for the parts of the flowsheet that have been validated by pilot testwork. This work will enable a progressive commencement of the BFS engineering activities which is targeted for completion in mid-2021.
www.ferroalloynet.com