Applied Sorting Technologies (AST) has developed a new ore sorting technology that upgrades nickel sulphide ores. The unit uses a combination of conductivity and magnetic property sensors to enable the grade of each piece of ore to be compared against a predetermined cut-off as it passes through the Applied Sorting Machine. High-speed deflectors then separate out rocks that are below this cut-off.

The technology was originally developed for WMC Resources Ltd's Kambalda and Lenister nickel mines. The unit can handle run-of-mine ore ranging from 25mm to 150mm in diameter. Typically the crushed ore would be screened into two size fractions 65-150mm and 25-65mm with each fraction processed through a separate machine. Then depending on the grade unsorted fines may be combined with the accepted fraction or disposed of.

The unit can process the larger fraction at a rate of 50 t/h and the smaller at 25 t/h. AST notes that the ability to vary the sorters cut-off enables operators to choose between high upgrades of the ore, with the possibility that recoveries might be relatively lower, or high recoveries with a possibly lower upgrade.