Pareto profile benchmark for kinetics of filtration and extent of dewatering of fine and colloidal suspensions

Abstract

The time scale of the process and the extent of dewatering are principal performance measures of high pressure filtration of fine and colloidal suspensions which give rise to compressible filter cakes. Analysis of numerous filtration tests conducted under a wide range of suspension chemistry and process conditions suggests that it is not possible to improve the two performance measures simultaneously. As stipulated by the Pareto optimum, any improvement in the filtration kinetics can occur only at cost of reducing the extent of moisture removed from the filter cake and vice versa. The unique Pareto profile the curve of filtration kinetics versus extent of dewatering is the fingerprint of the filtration behavior of a particulate solid in suspension. Accordingly, any physical-chemical scheme, which purports to improve the overall filtration process, should be benchmarked against the Pareto curve.