Patent ID: 7635435
Filing Date: 2009-12-22
Classification: B01D,B01J,Y10S

Abstract:
1. A method of separating immiscible liquids in a dispersion comprising solids, an aqueous liquid and at least one non-aqueous liquid immiscible in the aqueous liquid and wherein the solids and the non-aqueous liquid are dispersed in the aqueous liquid, comprising: a) feeding the dispersion from a feed supply to a primary vessel having a plurality of coalescing compartments, in a first direction through the compartments from an initial upstream compartment to a final downstream compartment; b) partially coalescing the dispersed non-aqueous liquid through all the coalescing compartments; c) recovering a partially coalesced emulsion of said solids and said non-aqueous liquid, after passage through all the coalescing compartments downstream of said final downstream compartment, and d) periodically discontinuing the feeding in said first direction and feeding said dispersion in a second direction, counter to said first direction, such that said final downstream compartment of a) becomes a second direction initial upstream compartment and said initial upstream compartment of a) becomes a second direction final downstream compartment, wherein the coalescing compartment contains a coalescing media with a substantially homogeneous porous mass, the porous mass including a network of fine filaments and substantially uniform sized open cells in the filaments, wherein the uniform sized open cells have a cell diameter of 160 to 220 μm, and the coalescing media separating the partially coalesced emulsions from the aqueous phase by retaining said solids and said non-aqueous liquid, the emulsion having a droplet diameter of 0.5 μm or more, and, wherein said solids and said non-aqueous liquids are washed out of the coalescing media when the direction of feeding is changed in step d).