Experimental study of treating bottle washing waste alkali liquid of beer industry by coagulation

摘要

The bottle washing waste alkali liquid was treated by coagulation. The effect of coagulant type, the dosage of coagulant, the dosage of coagulant-aid, the temperature of coagulation, and the settling time on the waste alkali liquid were researched by the comparative experiment. The results indicated that when the polymeric aluminum chloride (PAC) dosage was 120 mg/l, the polyacrylamide (PAM) dosage was 2.5 mg/l, the temperature was 55°C and the settling time was 30 min, the waste alkali liquid's turbidity, COD and alkali concentration was 16.9 NTU, 553 mg/l and 0.73%, the removal rate of turbidity and COD, and the retention of alkali concentration was 91.4%, 67.9%, and 88.7%. The turbidity and COD of waste alkali liquid can be removed effectively and the alkali can be maintained at a high concentration. The alkali liquid after treating had recycling value and met the requirement of clean production.