Mr David Death looking at the focusing lenses of a laser-induced breakdown spectroscopy (LIBS) system.
Laser-induced breakdown spectroscopy for mining
Analysing light emissions from the plasma generated by laser pulses can provide insight into the elemental make up of a range of different materials.
11 March 2010 | Updated 14 October 2011
When a high peak energy laser pulse is tightly focused on the surface of a target, the concentrated light energy can be great enough to heat the surface to very high temperatures and break the material at the surface down into its constituent atoms.
The small bright flash created by the laser pulse is called a laser-induced plasma.
When the light emission from such a plasma is analysed the measurement is called laser-induced breakdown spectroscopy or LIBS.
The plasma light contains a great deal of information about the basic elemental make up of the material measured.
LIBS for elemental analysis
CSIRO's Process Science and Engineering division has developed the LIBS technique to provide detailed elemental analysis of a wide range of different materials including, wood, metal and rocks.
The LIBS technique provides detailed elemental analysis of a wide range of different materials including, wood, metal and rocks.
The data produced by the measurement comes in the form of a spectrum that shows the different light intensities emitted by the laser-induced plasma at different wavelengths, or colours. Each particular element has its own set of characteristic wavelengths that can be used to identify it inside a plasma or a flame.
By analysing LIBS spectra it’s possible to identify the elements on the measured surface.
By applying specialised mathematical treatment to LIBS data it’s also possible to determine how much of each element is present in the sample measured.
Current research focus
Our present focus is on making accurate measurements of the elemental make-up of rocks mined for metal production. So far we have measured samples including lateritic nickel ore and iron ore from Australia and overseas.
These measurements have demonstrated LIBS capacity for measuring elemental concentration down to around 100ppm of trace elements as well as those of major (>10 per cent) and minor (0.1-10 per cent) constituents. The ultimate goal of this work is to be able to make these measurements directly in the mine or mineral processing plant.
Read more about research leader Mr David Death: specialising in laser and imaging applications.