Simulation Analysis of a Mineral Liberation Estimator for Control Purposes

摘要

In the past few decades, extensive and intensive work has been done in the field of optimisation and control for mineral processing plants. As the valuable minerals have to be separated from the gangue through grinding, one of the most crucial process variables to monitor is the particle size. Although great advances have been accomplished, the vast majority of the proposed strategies relies on the control of a given product size index. The ultimate goal of comminution is mineral liberation, and it is not exclusively dependent on particle dimensions. Approaches focusing on liberation control rather than particle size could thus provide significant advantages. However, online measurement or estimation of mineral liberation is challenging to say the least. In this regard, there is still no work reported in the literature on the use of mineral liberation for online optimisation and control. This article explores the use of a mineral liberation distribution estimator for process control by investigating the effect of changing material properties and plant operating conditions. First, ore characteristics such as size distribution, mineral grades and grain sizes are varied to assess their impact. Then, the estimator is implemented as a liberation sensor in a simulated grinding circuit to observe the effect of modifying operating conditions. The results give a preliminary insight on the possibilities of using mineral liberation information for process control and optimisation purposes.