Windimurra Vanadium
Western Australia
Status: Commissioned 1999/2013
Role: Discoverer, CEO
Employees: 250 Direct, 250 indirect
Production: High Purity Vanadium Pentoxide 8,700 tpa and FeV
First Stage Development Capital: AUD$128m
Second Stage Development Capital: AUD$500m
World’s largest primary vanadium mine producing 10% of World Production.
Very complex metallurgy and process
ROM: 0.46% Vanadium 2 mtpa
Initial Project Development $128 m, Redeveloped 2013 $500 m
Overview
In 1988, Roderick Smith discovered the extent of vanadium mineralisation in the Windimurra Intrusive in Western Australia. He floated Precious Metals Australia Limited (later renamed Windimurra Vanadium Limited) and led the company through discovery, evaluation, process development, feasibility studies and construction.
Precious Metals Australia, in partnership with global mining company Xstrata, constructed the world’s most advanced vanadium plant at Windimurra. The Windimurra vanadium plant is one of the most metallurgically complex process plants of any kind in Australia, involving crushing, grinding, desliming, magnetic separation, roasting, leaching, precipitation, clarification, reduction and fusing of a pure product.
The Windimurra vanadium circuit has some similarities with proposed lithium extraction circuits where a mica concentrate is produced by gravity and magnetic concentration, then roasted and leached.
Mineralogy
The mineralogy of Windimurra is similar to the vanadium found in South Africa, hosted in a Vanadiferous Titanomagnetite.
Beneficiation process
The beneficiation process featured primary jaw crushing, followed by SAG (semi-autogenous grinding) milling. The milled product was sent to rare earth high intensity magnetic separation circuit to produce a concentrate with double the vanadium grade and reduced silica and calcium. The magnetite concentrate is roasted with a sodium flux at 1200oC in a 126 m rotary kiln to convert to water soluble sodium vanadate. This is leached in hot water and a complex hydrometallurgical circuit removes impurities and precipitates an insoluble Ammonium Meta Vanadate (AMV). The AMV is dried in a flash dryer and reduced in a rotary reduction furnace to V2O3 or V2O5. V2O3 is further reduced aluminothermically in an electric arc furnace.
Prior to Windimurra’s development, the only primary vanadium producers in the world were in South Africa, Siberia and China who used large unskilled workforces and comparatively low-tech processes. Windimurra was unique in the high level of technical development, automation, process monitoring and control that was developed in Australia by Roderick Smith’s team.