A new technology for removing arsenic from copper, lead and nickel concentrates has been selected as a top 5 finalist in the Australian Innovation Challenge awards, Minerals and Energy category. Called the “Toowong Process” – after the Brisbane suburb – it is a new hydrometallurgical technology that enables operations to remove arsenic, antimony, tin and mercury at the mine site prior to shipping a cleaned concentrate product.
The technology has been developed by Core Resources, a Brisbane based mineral processing laboratory and engineering group.
Arsenic is a globally significant issue for the copper industry. Average arsenic grades are increasing, as are restrictions on the amount of arsenic smelters are willing to accept – putting pressure on many existing copper operations, and making several major global copper mineralisations unviable for mining.
About the Technology
The Toowong process selectively leaches arsenic, antimony, tin and mercury from specific minerals using a patented Alkaline Leach technology. Critically, it removes the unwanted elements without substantially affecting the copper minerals – the cleaned concentrate is suitable for shipping directly to smelters. This eliminates the need for downstream copper metal recovery processes.
Using process chemistry developed at Core, the alkaline leach process is also largely self-sustaining. Most of the reagent requirements are either generated from the concentrate in situ in the leach, or recovered downstream and recycled.
The leached arsenic is fixed using standard technologies into a stable, non-toxic form that can be managed in its original native location at the mine site – instead of being shipped to smelters across the world.
Development
The development of the process has spanned several years. This culminated in 2012, with Core designing, constructing and operating a $2.5m hydrometallurgical pilot scale demonstration of the process. Over 34 days, 1.2 tonnes of Tampakan concentrate was treated. Arsenic removal of 90%+ was demonstrated at steady state conditions, lowering the As grade from 1.1% to 0.1%. The product from the pilot plant was a cleaned copper concentrate suitable for sale. The technology is now the subject of a worldwide patent.
Commercialisation
The Towong Process is a potentially game-changing technology. Professor David Way of JKTech writes, “The Toowong Process has the potential to unlock sites throughout the world that are currently considered unviable mineralisations for sustainable mining”
Peter Munro, Senior Principal Consulting Engineer at Mineralurgy Pty Ltd, writes, “This really looks like a “win-win” situation as by using this Toowong Process the miners will be able to treat ore from existing operations that are high in arsenic and develop new deposits containing arsenic. Smelters will receive “clean” copper concentrate minimizing the problem of disposing of toxic wastes and residues which is becoming a major issue for operations even in China.”
Core is currently seeking commercialisation and development partners to enable the roll-out of the Toowong Process to industry. “We have seen strong interest from a number of groups from across the industry,” says Peter Rohner, Core’s CEO.
The Australian Innovation Challenge winners will be announced on November 25 at the awards ceremony at the Questacon in Canberra. The Toowong Process is the only mining related technology in the Minerals and Energy category.
About Core
Core Resources (www.coreresources.com.au) provides testwork and process engineering services to the global mining industry, and includes the former Hydrometallurgy Research Laboratories. The group specialises in the development and piloting of complex mineral processing flowsheets. Core has extensive experience in the development, testing and commercialisation of mineral technologies through its work on the Albion Process.
Further information:
http://www.coreresources.com.au/process-innovation/the-toowong-process/
http://www.theaustralian.com.au/innovationchallenge
David Walker (Business Development Manager)
[email protected], +61 7 3637 8115, +61 4 08 686 395