LAUSR

Abstract As minerals frequently appear in complex associations in nature, liberation is one of the most relevant aspects in ore processing, and is achieved through comminution, which certainly is one of the most important but also expensive operations in industry. The global efficiency of the plant often depends on the performance of the grinding circuit, so there is a compromise between particle size, energy consumption and liberation. An adequate prediction of the liberation of grinding products can be helpful in reducing overgrinding, and therefore, reducing energy consumption without disturbing downstream operations. This paper addresses the development and validation of a mineral liberation model which is intended to be integrated in a simulation framework for comminution processes. Mineral species contained in the ore are distributed into size and liberation classes. Firstly, the size-by-size mineralogical distribution is related to the size distribution of the ore by means of a polynomial model. The next stage is to sort the mass of every species in every size class into liberation classes by means of a beta distribution function, whose characteristic constants are parameterised according to the ore properties. Results show great potential of the model to represent commonly observed industrial data, which provides opportunities for process simulation, optimisation and, to a lesser extent at this point, process control.