Posted by Daniel Gleeson on 13th October 2021
Tharisa, the platinum group metals (PGMs) and chrome co-producer, has announced that cold commissioning of its Vulcan ultra-fine chrome recovery and beneficiation plant has commenced.
The timetable to completion of the new $55 million plant remains firmly on track with initial saleable production due before year end, it says.
Once fully commissioned, the plant is expected to see Tharisa Mine, in South Africa, materially increase its chrome recoveries from circa-62% to circa-82% resulting in increased chrome production of some 20% at low incremental unit operating costs.
The plant, which will process live tailings produced by the independent Voyager and Genesis plants, will ensure further beneficiation of the company’s chrome production at the Tharisa Mine, while reducing unit output of carbon emissions, aligned with Tharisa’s recently announced decarbonisation plan, the company says.
The Vulcan plant has a nameplate capacity of 340,000 t/mth of tailings and involves “proprietary ground-breaking use of existing technologies in fine chrome recovery”, the company says. The board initially signed off its construction in 2019, appointing Wood as the engineering, procurement and construction management contractor in the process, with hot commissioning targeted for the December quarter of 2020. This timeline was impacted by COVID-19.
Some final elements of the construction process remain to be completed, yet Tharisa’s engineering team has commenced cold commissioning, with comprehensive testing of the entire circuit, to be completed prior to chrome tailings material entering the plant. Of the total capital expenditure, over 90% was procured locally in South Africa, with up to 1,000 contractors locally sourced and over 100 new permanent jobs created.
Vulcan is, Tharisa says, the first large-scale plant to produce chrome concentrates from chrome ultra-fines. The concept of Vulcan was developed by Arxo Metals Proprietary Limited, a wholly owned subsidiary of the company and housing Tharisa’s in-house R&D team, to extract the ultra-fine chrome from tailings.
With Tharisa Mine near Rustenburg having a 14-year open-pit life remaining, and a further 40 years underground, Vulcan will ensure maximum value extraction and beneficiation of the chrome ore, Tharisa says. The Tharisa Mine has 860 Mt in mineral resource containing 172 Mt in contained Cr2O3 and 42.8 Moz platinum group metals.
Internally funded by Tharisa, Vulcan recommenced construction in October 2020 after the lifting of restrictions by the South African government during the height of the first wave of the COVID-19 pandemic.
Phoevos Pouroulis, CEO of Tharisa, says: “Commissioning of the Vulcan plant perfectly exemplifies two Tharisa philosophies: challenging convention through innovation and delivering on our promise of maximising value through beneficiation of every cube mined.
“Vulcan provides the company with the ability to further beneficiate our product whilst staying on track to meet our decarbonisation targets, thanks to the dedicated work from Arxo Metals, that has not only delivered the Vulcan process but has also delivered further beneficiation opportunities, including metal alloys and PGM products using non-conventional methodologies.
“Vulcan is an important part of our sustainable growth strategy and ensures that Tharisa continues to drive sustainable returns for all of our stakeholders, while simultaneously pushing us even lower on the cost curve.”