Minerals Processing 1993

In his keynote address at the 18th International Minerals Processing Conference (IMPC), R.P. King, director of the University of Utah Comminution Center, said "it will be the application of very fundamental physical principles that is likely to bring major advances in comminution technology (IMPC, pp. 39-45)." It is evident from the literature published in 1993 that many of these fundamental studies, particularly as they relate to single-particle fracture mechanics and mineral liberation, are starting to bear fruit. The beginnings of fundamental mathematical models for design, scale-up and control of comminution systems are now taking shape. Modeling/fundamentals Population balance models (PBM) have been used to describe grinding systems for 20 to 30 years. However, Williams and Meloy (IMPC, pp. 73-79) pointed out some of the inherent problems with this modeling approach and that there is no unique solution for the unconstrained PBM for grinding. Many of the current constraints used to back-fit selection and breakage functions were also shown to have problems. The need for a more fundamental means of determining these parameters was indicated.