GB644910A - Continuous extraction apparatus and process - Google Patents

Abstract

<PICT:0644910/III/1> An oil - containing substance is continuously extracted with a solvent by placing it in a receptacle movable in a continuous horizontal circular path, extracting the contents of the receptacle a number of times with solvent of gradually decreasing solute content, the solvent after each extraction being applied to a succeeding receptacle and fresh solvent being added to each receptacle whilst in its last position but one. The process is effected in an apparatus comprising a plurality of receptacles R1-R8 attached to a rotatable vertical spindle 3, each receptacle being provided with a combined filter bottom 12 and collecting tray 14, Fig. 3, pivotally attached along one edge to the receptacle and the other edge being supported via rollers 15 by means of a discontinuous trackway comprising two rails 17. A charging hopper above receptacle R1 charges the receptacles <PICT:0644910/III/2> successively. Solvent is introduced from a reservoir to a sprayer S1 into receptacle R6 and collects in the collecting tank T1 beneath whence it proceeds through an outlet O1 and pump P1 to a p sprayer S2 and similarly in succession through the tanks T2-T6, pumps P2-P5 and sprayers S2-S6 and outlets O2-O5, the strong solution having passed through the newly charged receptacle R1 being collected from an outlet O6. A gap in the rails 17 under compartment R8 permits the hinged filter bottom and collecting tray to drop, discharging the contents of this compartment via a shoot 20. A cranked bar 22 and counterweight 23 controls the descent of the filter bottom. The receptacles are preferably maintained in continuous movement but with solids of high oil content, it may be preferable to make the movement discontinuous, the solids being treated with solvent which all drains into the collecting tank beneath before the receptacles are moved forward to the next position.