Apparatus for liquid-liquid extraction

Claim 1

A multi-stage liquid-liquid extraction apparatus of the mixer-settler type for carrying out extractions involving light and heavy phases accompanied by a solid phase settling comprising (a) a vessel, the essentially vertical side-walls of which define a cylinder or a regular polygonal body and the bottom of which is inclined downwardly from the side wall towards the central axis of the vessel so that the bottom resembles a reversed cone or pyramid; (b) a pluarality of partitions dividing the vessel into a plurality of sectors, said partitions extending radially outwardly from the central axis of the vessel to said sidewall; (c) a liquid mixing compartment located in each sector near the side-wall of the vessel, said compartment containing liquid inlet means for said light and heavy phases, (d) an agitator in each mixing compartment in the form of a pumping turbine for mixing the phases, (e) an outlet for each mixing compartment in the form of a weir that is located a spaced distance away from the side-wall of the vessel, (f) a liquid outlet compartment in each sector located near the side-wall of the vessel, said compartment containing two separate outlet means for discharging two separate liquid phases from said compartment, (g) guide means including a baffle wall in each sector extending from the outlet of the mixing chamber toward the central axis of the vessel for guiding the mixed phases from the weir of said mixing compartment towards a zone located near the central axis of the vessel and then in a nearly reverse direction outwardly towards said liquid outlet compartment, and (h) an outlet for solids adjacent to the apex of said reversed cone or pyramid.