an alternative technique is presented for reducing the production of fines ( particles of less than 212 mm in size) during the crushing process applied to copper minerals. the proposed method included pneumatic separation of the fines from an ascending flow of air applied to artificially prepared samples of crushed mineral which were prepared containing various quantities of fines ranging from 10 to 25% by weight. laboratory tests verified separation of the fines from the samples using the proposed method. in static bed tests, separation of nearly 90% was obtained, starting with ratios of (u0/ut) = 2 (for a prepared sample containing 20% fines and surface air velocity of u0 = 100 cm/s). on the other hand, tests with a moving bed gave a separation near 75% for similar samples and working conditions. this behavior was repeated for all the test samples prepared. these results allowed validation of the alternative technique for the pneumatic separation of fines from currents of crushed minerals
