Mill Speed as a Manipulated Variable for Ball Mill Grinding Control

Abstract The effectiveness of grinding control strategies is limited, at least in part, by a lack of fast acting, non-interactive variables which may be manipulated in response to disturbances. Currently used manipulated variables include feed rate, water additions and pumping rates. Because of the highly interactive nature of control loops based on these variables the effectiveness of current strategies is suboptimal In the current study the feasibility of using mill speed as a manipulated variable is evaluated computationally and experimentally. A control system simulator, DYNAMILL, was used to screen alternative strategies involving the manipulation of mill speed using parameter values obtained in a 0.5 tph computer controlled pilot circuit. The practical implications of the findings are discussed.