Industrial Minerals - Cyclone Classification of Artificial Abrasive Powders

Experimental results indicate that wet cyclones could be effectively used for the preliminary classification of the tested synthetic abrasive materials, thus supplementing the currently used sedimentation method. An empirical formula is also proposed on the basis of the test data to calculate the particle size of separation. One of the basic operations in the abrasive industry is the classification of the crushed and ground materials into different sized products. The relatively coarse grains, plus 325 mesh, are commonly sized by dry screening with satisfactory results. On the other hand, however, the currently used grading tank, for classifying grains finer than 325 mesh, is intermittent. Consequently, it is difficult to operate efficiently and keep pace with erratic market requirements. Little success was made in an attempt to substitute air settling and continuous hydraulic settling for the grading tank, because size specifications1 for abrasive powders are very stringent and difficult to meet. Finally, a wet cyclone was chosen for experimentation. Even though wet cyclones have not been extensively used in the classification of abrasives; however, their performance as a classifier has been verified by Driessen2,4 on coal, McCarrel5 with manganese, and Herkenhoff6,7 on iron ore. Experimental work on silicon carbide, boron carbide, and fused alumina has shown that the cyclone