King River Resources is exploring the potential to add another revenue stream to its massive Speewah specialty metals project in WA’s Kimberley region with the successful production of high purity alumina, or “HPA”, during metallurgical test work.
Whilst metallurgical refining test work was initially focused on recovering iron, aluminium and titanium, testing confirms that 99.99% alumina can be extracted from the sulphate leach solutions before the solution had any other metals removed or had been pre-concentrated.
Further tests will be carried out to improve precipitation efficiency, reduce the amount of hydrochloric gas required and increase recycling of hydrochloric gas.
King River will also trial three different precipitation methods to develop the best technique for producing HPA.
HPA is used to produce sapphire glass used as substrates in the light‐emitting diode, semi-conductor and laser markets.
It is also used to coat separators for lithium batteries, a use that is becoming increasingly common due to its ability to improve both efficiency and safety.
King River is currently taking steps to try and include aluminium and magnesium into its JORC resource estimates for the Speewah project.
Speewah is a remarkable deposit, with a huge global resource of 4.7 billion tonnes at 0.3% vanadium pentoxide, 3.3% titanium dioxide and 14.7% iron.
The company switched its focus to sulphuric acid-based processing late last year in a bid to dramatically reduce the previously estimated CAPEX costs of between $2 billion and $2.5 billion to develop Speewah.
This appears to have been the right tack to take with Como Engineers concluding in March that the CAPEX for the processing plant and the acid plant was likely to be closer to USD$676 million.
Several other ASX miners are also looking to develop HPA projects in Australia such as Alchemy Resources and Altech Chemicals. The latter has already started initial construction at its processing plant in Johor, Malaysia.
