Table of Contents
Physical Separation in Science and Engineering
Volume 13 (2004), Issue 1, Pages 1-13

Master Curve of Separation Processes

1Negev Academic College of Engineering, Beer-Sheva, Israel
2The Institutes for Applied Research, Ben-Gurion University of the Negev, P.O.B. 653, Beer-Sheva 84105, Israel

Received 6 January 2004; Revised 24 February 2004

Copyright © 2004 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Processes of gravity classification involve complex two-phase flows with a multiple-fraction solid phase. Analytic solutions are still lacking for mass processes that comprise solid particles moving in different directions. Consequently, research on gravity classification has been restricted to the study of empirical regularities. This article presents the latest results in this area. Basic to these results is a new physical phenomenon that has been found to apply to the entire class of gravity separation processes – equivalency of the recoveries of the different particulate fractions. In the turbulent zone this regularity is invariant under the main technological factors of the process: flow velocity of the medium, size and density of the particles, density of the medium, concentration of the solid phase. A method has been found for transforming the main process parameters in the laminar and transitional zones to yield identical correlations. This points to the existence of an underlying law governing the process.