DE-XRT sorting of Coal

The minimum particle size is 5 mm. The machine is, relative to a conventional wash plant, compact and can also be constructed as mobile device. This allows on-site refill of reject and easy displacement following the worked seams or sections. Relative to other automatic sorting techniques it has the advantage that the sorting is independent on moisture fluctuations, surface dirt, and shape or size effects. Relative to dry physical separation techniques it shows a much higher efficiency and is suitable for a wider size range (5 to 150 mm). The present work presents results on the efficiency of DE-XRT sorting for a variety of coal and coal reject types. These include the lowering of ash in washed coal, the sorting of run-of-mine coal and the recovery of residual coal from mine reject and historic waste dumps. The possibilities of DE-XRT sorting are very much determined by the washability (liberation) of the various types of coal. For this reason, whenever a DE-XRT application for coal is considered, a tailor made experimental procedure is required to indicate the results that can be expected.