Patent ID: 8119004
Filing Date: 2012-02-21
Classification: B01D

Abstract:
1. A method of effecting liquid-liquid separation using at least two counter-flowing liquids each of which flows through a vertically aligned treatment zone, the treatment zone having a longitudinal axis and a bottom end that is spaced apart from and disposed below a top end, which method comprises: a. establishing a flow of a feed fluid composition in a first direction through the treatment zone, the first direction being from the bottom end to the top end, the feed fluid composition (1) comprising a first liquid and a removable solute, (2) being at least partially saturated with a dispersible gas, and (3) having a first density, the feed fluid composition being present under a pressure sufficient to maintain at least a portion of the dispersible gas in solution as the feed fluid composition enters the treatment zone, yet insufficient to maintain the dispersible gas in solution as the feed fluid composition traverses the treatment zone from the bottom end to the top end, such that at least a portion of the dispersible gas comes out of solution as the feed fluid composition traverses the treatment zone, moving from the bottom end to the top end, and having a first mass flow rate; b. establishing a flow of a wash fluid composition in a second direction through the treatment zone, the second direction being from the top end to the bottom end, the wash fluid composition comprising a second liquid, the second liquid (1) being either immiscible or, at most, partially miscible with the first liquid such that their intimate contact does not yield a single liquid phase, and (2) having a density that is greater than the first density; c. effecting operative contact between the flows of feed fluid composition and wash fluid composition while imparting sufficient mechanical energy to the flows to effect distribution of one fluid composition as a dispersed phase suspended within a continuous phase comprising the other fluid composition, the mechanical energy having a greater intensity at the bottom end of the treatment zone than at the top end of the treatment zone, the operative contact being sufficient to effect transfer of at least a portion of the removable solute from the feed fluid composition to the wash fluid composition, thereby converting the feed fluid composition to a raffinate liquid and the wash fluid composition to an extract liquid; and d. removing the raffinate liquid from the top end of the treatment zone and the extract liquid from the bottom end of the treatment zone.