Patent ID: 7993052
Filing Date: 2011-08-09
Classification: B01F

Abstract:
1. An agitation mixer for agitating a solution and a solvent that precipitates a solid substance dissolved in the solution, the agitation mixer comprising: an agitation vessel; an impeller including radially extending rotor blades rotatably arranged in the agitation vessel for shearing the solution and the solvent when rotated; a feed unit having a feed pipe structure formed of a plurality of feed pipes including an inner pipe and an outer pipe arranged outside the inner pipe; a discharge port for discharging agitated fluid from the agitation vessel; and a screen having through holes and arranged around the impeller so as to form a clearance between distal ends of the rotor blades and an inner surface of the screen in the agitation vessel; wherein a shearing clearance is formed between the feed unit and the radially extending rotor blades of the impeller, the outer pipe feeds one of the solution and the solvent to the shearing clearance, the inner pipe feeds the other one of the solution and the solvent to the shearing clearance, and the solution and the solvent initially come in contact with each other in the shearing clearance.