Combined tool cuts costs and complexity
CSIRO has developed a prototype slurry analyser capable of measuring both mineralogy and ultra-low elemental composition directly on a process stream, thereby avoiding labour-intensive, time-consuming and potentially error-prone sampling.
The minerals industry has traditionally relied on two different x-ray-based technologies to determine a material’s characteristics; x-ray diffraction (XRD) for mineralogy and x-ray fluorescence (XRF) for sensitive chemical composition analysis.CSIRO researchers were developing separate XRD and XRF slurry analysers when they began to realise the designs had similarities and there could be value in combining them into the one tool. “We’ve taken the best aspects of XRD and XRF analysis technologies to create the new prototype,’ says CSIRO’s Dr James Ticker, who heads the team developing the analysers.
The result is a single tool capable of providing simultaneous mineralogical and elemental analysis. An added benefit is a near halving in the tool’s cost and complexity, meaning the new tool is a more compact and cost-effective product.
The technology, dubbed XRDF for its dual origins, has been designed to operate directly on-stream for plant control and monitoring applications. It measures a material’s characteristics as it passes through the analyser in the form of a slurry. By using a launder tank geometry, a wide range of flow rates, up to 100 litres per minute, can be accommodated. The analyser reports updated composition parameters every minute, allowing rapid responses for plant control.
The XRDF prototype can be readily adapted to measure different elements and minerals, making it well-suited for a wide range of applications and industries.
Dr Tickner says that for elemental analysis, the prototype is 10 times more sensitive than other commercial slurry analysers. “XRDF can detect down to a level of about 100 parts per billion, allowing us to measure valuable metals such as gold, silver, uranium and the platinum group elements which may only be present at levels of a few grams per tonne or less.”“We are not aware of any other system capable of doing accurate, on-stream mineralogy, and we have already received considerable interest from industry representatives about our prototype,” Dr Tickner says. “And the ability to detect elements at parts-per-billion levels in an on-stream system is unique.”
The first industrial prototype, being developed now, will undergo an industrial trial in early 2010.
Image caption: Online analysers recently installed at an Australian concentrator. Credit CSIRO