REDUCING WASTE STREAM POLLUTANTS BY CONTROL amp; SEPARATION OF WASTE CONTAMINANTS FROM MULTI-STATE CELLULOSIC BLEACHING SEQUENCE

摘要

Case 3317/WJC:lm CONTROL AND SEPARATION OF WASTE CONTAMINANTS FROM A MULTI-STAGE CELLULOSIC BLEACHING SEQUENCE A method is provided for reducing waste stream pollutants by the control and separation of color bodies, COD, BOD and other organics from inorganic chloride pollutants in the aqueous waste effluent of a cellulosic pulp bleaching process containing a sequential chlorination stage (Dc) or mixture (D/C) stage followed by an extraction (E) or oxygen (O) stage, comprising, maintaining the conditions of the Dc or D/C stage such that the pulp product therefrom is low in inorganic chloride and organically bound chlorides and the waste effluent therefrom is low in organic distribution as compared to the subsequent E or O stage waste effluent, passing said waste effluent through an activated bed, under conditions wherein color bodies, COD, BOD and other organics are selectively removed therefrom without significant. effect upon the inorganic chloride content; maintaining conditions in the E or O stage such that the waste effluent therefrom is high in organics distribution but low in inorganic chloride distribution as compared to the Dc or D/C stage waste effluent; and passing at least some of the E or O stage waste effluent, intermittently from the Dc or D/C stage waste effluent, through the activated bed under conditions sufficient to elute the color bodies, COD, BOD and other organics therefrom.