ENERGETIC APPROACH TO KINETICS OF BATCH BALL-MILLING

Kinetics of batch milling is proposed to express with respect to energ y instead of time. A model is applicable to various processes taking p lace in a mill (size reduction, mechanochemical transformation, etc.). A model is similar to classical chemical kinetics with the time subst ituted by the energy, and the temperature substituted by the intensity of treatment. Definition of the intensity is proposed for drum mills with loose ball media (tumbling, vibratory, planetary, and stirred mil ls). The general rate constant is introduced as a product of the tempe rature-dependent conventional rate constant and the intensity-dependen t factor of energetic efficiency, A technique for determination of the energetic efficiency is proposed and illustrated with experiments. Th e energy-scaled model of milling kinetics makes possible the comparabi lity of experimental data obtained in various mills under different in tensities of treatment and, therefore, the mills scaling-up. (C) 1998 Elsevier Science B.V. All rights reserved.