Recovery of sugar from clarifier scum by countercurrent extraction

Claim 1

A CONTINUOUS PROCESS FOR RECOVERING SUGAR FROM THE CLARIFIER SCUM PRODCED BY PHOSPHATION-FLOATION IN SURGAR REFINING, WHICH PROCESS COMPRISES: SUBJECTING THE SCUM TO AT LEAST TWO CONSEUTIVE STAGES OF COUNTER-CURRENT AQUEOUS EXTRACTION, WHEREIN EACH EXTRACTION STAGE COMPRISES THE SUCCESSIVE STEPS OF A. DISPERSING THE SCUM IN DESWEETENING WATER, TO GIVE A HOMOGENEOUS MIXTURE, AND AERATING THE MIXTURE, B. DISTRIBUTING AN ANIONIC ORGANIC POLYMERIC FLOCCULANT UNIFORMLY THROUGHOUT THE AERATED MIXTURE, TO FLOCULATE THE SCUM THEREIN, C. PASSING THE MIXTURE, WITHOUT FURTHER AGITATION, TO A CLARIFIER, D. ALLOWING THE FLOCULATED SCUM TO SEGREATE FROM THE MIXTURE BY FLOATATION IN THE CLARIFIER, AND E. SEPARATELY REMOVING A CLARIFIED DILUTE SURGAR SOLUTION AND FLOCCULATED SCUM FROM THE CLARIFIER, PASSING THE FLOCULATED SCUM FROM THE STEP (E) OF EACH EXCEPT THE LAST EXTRACTION STAGE (A) OF THE NEXT EXRACTION STAGE, PASSING THE DILUTE SUGAR SOLUTION FROM STEP (E) OF EACH EXCEPT THE FIRST EXTRACTION STAGE (A) OF THE I MEDIATELAY PRECEDING EXTRACTION STAGE, FOR USE AS DESWEETENING WATER THEREIN, DISCHARGIING THE FLOCCULATED SCUM FROM STEP (E) OF THE LAST EXTRACTION STAGE, AS DESWEETENED SCUM, AND RECOVERING THE DILUTE SUGAR SOLUTION FROM STEP (E) OF THE FIRST EXRACTION STAGE.