Measurement of a proxy for froth phase bubble sizes as a function of froth depth in flotation machines Part 1. Theoretical development and testing of a new technique

An electro-resistivity technique for measuring a proxy for froth bubble sizes as a function of height above the pulp–froth interface has been developed. Froth phase bubble size measurements were performed in a laboratory mini-flotation column. Comparison of the proxy herein termed average intra-bubble impact distance (IID) from this new technique to the Sauter-mean diameter from the conventional photographic method established a linear correlation. The average IID from the new technique was higher than the Sauter-mean diameter at all froth segments. Both techniques were able to capture the general increase in bubble sizes as a function of froth height.