A model for static filtration of emulsions and foams

✍ Scribed by J.D. Sherwood

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 643 KB
• Volume: 48
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(93)80152-g

✦ Synopsis

A model for the filtration hehaviour of emulsions is presented. The droplets within the emulsion have undisturbed radius a, interfacial tension coefficient y and are incompressible: the viscosity of the continuous phase is q. Estimates are obtained for the permeability of, and stress within, the matrix of droplets forming the filter cake, and the standard theory for static filtration is then applied. The fluid loss per unit area is equal to St"', where the constant S scales as (y~/s)"~_ S is independent of the applied filtration pressure pm as long as pm is sufficiently large compared to Y/a: the variation of S with the volume fraction of the emulsion is examined. The pressure within the emulsion droplets varies across the cake by an amount O(y/a). If this change in pressure is sufficiently small for the compressibility effects to be neglected, then the analysis will also be valid for compressible droplets (e.g. for foams).