The experimental investigations have been provided for the explanation of the influence on the grinding process of granular material of ferromagnetic particles moved by means of the rotating magnetic field (the application of magnetically driven fluidization). A new approach of the mathematical description of the grinding process has been presented by means of the maximal entropy principle (MEP) approach based on the maximization of the informational entropy. The experimentally identified results of the proposed model have presented the possibility of the adequate prediction of the particle size distribution (PSD). (C) 2010 Elsevier B.V. All rights reserved.