[Streaming current of waterworks sludge]

The applicability of streaming current in waterworks sludge treatment as indicator of coagulant dosage and pH control was investigated in this study. Experiments were conducted on sludge settling behaviors and dewatering processes. At the aspect of sludge settleability research showed the theoretical optimal dosage, pH was 8.9mg/L, 7.25, and the practical optimal dosage, pH was 9.0mg/L, 6.90. On the side of sludge dewaterability, the theoretical optimal dosage, pH was 25.0mg/L, 9.25, and the practical optimal dosage, pH was 26.0mg/L, 9.0. Results indicated that slightly positive streaming current coincided with the optimal dosage and pH. Thus streaming current can be used for continuous dosage feedback control as the single indicator.