Filtration of deformable emulsion droplets.

Abstract Oil-in-water (o/w) emulsions of different droplet size were filtered on membranes of various pore sizes to investigate the growth and behaviour of o/w filter cakes. The cake desorptivity S and the filter membrane resistance R were measured at various filtration pressures P . The variation of S with P shows that filter cake oil droplets of radius a are effectively rigid for P ≪ γ / a and fully deformable for P ≫ γ / a , where γ is the oil–water interfacial tension. For the largest P , when S became P -independent, the filter cake remained water-permeable as expected from theory.