pH control in flotation process based on prediction model

The pulp pH value is an important controlled variable for process operation in mineral flotation process,which is controlled through regularly adjusting reagent dosage by experienced workers according to the pH measurement results of the current pulp samples.However,due to the influence of the subjectivity and casualness of workers and the long time-lag between the pH measurement of the pulp sample and the reagent adjustment,the pH value of the pulp fluctuates frequently,causing unstable and undesirable production states for mineral flotation.A novel pH control method is proposed to maintain the pulp pH value at an expected production state based on the froth visual information.Firstly,a pH prediction model and a pH control model are built by froth visual information based on the adaptive genetic hybrid neural network(AG–HNN) and adaptive genetic PID(AG–PID) control method,respectively;and then the dosage is adjusted according to the pH value prediction model and the pH control model.Several industrial-scale experiments demonstrate that this method can maintain the pH value of the pulp in an expected range and consequently improve the flotation performance effectively.