Tomra Mining has installed a first X-Ray transmission (XRT) ore sorter at Saloro’s tungsten mine in Barruecopardo, Spain. The sorter, implemented in the beneficiation stage, is consistently delivering a much higher head grade to the processing plant, significantly reducing costs.
The Saloro mine is one of the most important in Europe, and one of the few outside China that produces concentrate with high tungsten grade with limited impurities, making it a high-value product in the industry.
Saloro approached Tomra to explore ways to further improve the head grade to the processing plant. “We were looking for equipment capable of sorting ore with scheelite content in order to remove the non-mineralized product from the feed line,” explains Pedro Jiménez, plant manager at the mine.
Tomra proposed its XRT ore sorter, which has the capability to identify fine dense tungsten inclusions with a detection technology developed in-house. “Our ‘inclusions technology’ is a perfect combination of a high-resolution XRT sensor with tailored sorting algorithms,” explains Carolina Vargas, area sales engineer at Tomra. “At the Barruecopardo mine, this technology enables the detection of 1-mm or even smaller tungsten inclusions. This is unique in the market.”
Tomra conducted tests with its XRT technology on 10- to 30–mm and 30- to 60-mm particle sizes at its German test centre in 2019 with positive results. “We chose Tomra because of the reliability of the equipment in the tests and the time required to supply it,” adds Jiménez.
In July 2023, Tomra installed a COM tertiary XRT ore sorter at the mine. It is fed with raw material in the 8- to 25-mm size range at a rate of around 30 t/h. The sorter achieves +90% recovery of scheelite and removes 85% to 90% of host rock prior to downstream processing through gravity concentration, magnetic separation, and flotation. By only processing the material with scheelite content, the plant achieves significant cost savings.
Jiménez says the results have convinced Saloro to purchase more ore sorters to further increase the feed grade to the mill.
Source: Canadian Mining