STEINERT has brought its magnetic and sensor-basedsorting systems from the disposal and recycling sector into the miningindustry.
STEINERT offers other sensors that can be combined withXRT to determine and sort individual chemical elements very precisely. Opticalsorting and lasers, for example, are well suited to the detection of ores withdifferent colours, such as copper oxide, or crystalline structures in quartz, andcan be used alongside XRT.
One of the company’s multisensory sorting systems (KSS)recently made an impact at Braveheart Resources’ Alpine gold project nearNelson, British Columbia, Canada.
The purpose of the testing was to determine whether theSTEINERT ore sorting system and methodology could be used to upgrademineralised material originating from Alpine prior to trucking and processing.
The KSS machine in question incorporated a combination ofXRT and laser sensor technology, with the XRT targeting the atomic density ofthe material and measuring the X-ray attenuation of each particle with a directcorrelation on the mineral composition of the rock, and the laser sensortargeting the shape and brightness of a particle.
In preparation for testing of the ROM and compositesamples, the -10 mm fines were removed by screening. During testing, the ROMmaterial was upgraded from a feed grade of 14.7 g/t Au to 20.3 g/t Au with92.8% gold recovery and 32.7% waste rejection. The composite material wasupgraded from a feed grade of 25.4 g/t Au to 43.2 g/t Au with 81.3% recoveryand 52.1% waste rejection.
The test results were encouraging and indicated thesorting of mineralised material at the Alpine mine could be an “importantcomponent of Braveheart’s overall beneficiation process”.
By using ore sorting equipment, ore concentrates can becreated at very low cost in small or remote mining installations. The entireprocessing line can be planned in semi-mobile form and consists only ofcrushers, screens, belts and sorting machines.
