SOLVENT EXCHANGER AND METHOD FOR IMPROVING OF SOLVENT EXCHANGE EFFICIENCY Russian patent published in 2018 - IPC C07C63/26 C07C51/42 B01D33/06 

FIELD: chemistry.

SUBSTANCE: present invention relates to a solvent exchanger and a method for improving the exchange efficiency of a STK solvent. Method comprises the following steps: (1) feeding STK suspension under pressure into the solvent exchanger to separate and produce a mother liquor, a mother liquor with a displaced stream and a suspended substance A, respectively; (2) washing suspended substance A to produce a first filtrate, a first filtrate with a displaced stream, and a suspended substance B, respectively; (3) washing suspended substance B to produce a second filtrate, a second filtrate with a displaced stream and a suspended substance C, respectively; (4) washing suspended substance C to obtain a third filtrate, a third filtrate with a displaced stream, and a suspended substance D, respectively; (5) washing suspended substance D to obtain a fourth filtrate, a fourth filtrate with a displaced stream, and a suspended substance E, respectively; (6) washing suspended substance E to produce a fifth filtrate, a fifth filtrate with a shifted stream and a filter cake, respectively, wherein the fifth filtrate with the displaced stream is sent to the filtrate tank with the displaced flow by a suction machine; and (7) after completion of washing, washing filter residue, preparing the slurry mass, and withdrawing the slurry. Positions of the separation units in the control unit can be adjusted so that the residual filtrate in the filtrate line can be taken to the respective chambers during the solvent exchange without entering the low-concentration washing liquid into the following stages.

EFFECT: due to improvement of the technological process and design of the equipment the present invention significantly reduces energy consumption, improves exchange efficiency of the solvent, reduces the amount of the required washing liquid in the system, helps to prevent contamination of the filtered precipitate.

4 cl, 3 dwg