Probability Density Function of Bubble Size Based Reagent Dosage Control for Flotation Process

Abstract As an effective measurement of bubble stability, bubble size structure is believed to be closely related to flotation performance. Reagent dosage has a very important influence on bubble size. A novel probability density function (PDF) of bubble size based reagent dosage control method is proposed in the paper. First, froth images acquired by camera with big and tiny blobs are segmented by use of an improved two‐pass watershed algorithm. With non‐Gaussian features, the PDF of the bubble size is hence approximated by the estimator based on B‐spline such that the PDF of the bubble size is characterized by a weight vector of the B‐spline. Finally, a PDF‐based reagent dosage control algorithm is proposed to make the output PDF track the given PDF according to the linear matrix inequality technique, which is established to solve its stability condition by Lyapunov stability analysis. Experimental results show the effectiveness of the proposed method.