In conventional treatment of variable quality mountain water, an inability to immediately adjust the coagulant dose to variations in water quality causes overdose or underdose of coagulant in relation to its optimal value. The results of the research showed that the reuse of post-coagulation sludge was an effective method to maintain high and stable coagulation effectiveness under both polyaluminium chloride (PACl) overdose and underdose conditions. Recycled sludge contains a large portion of insoluble aluminium hydroxides that could be utilized in underdose PACl conditions. Post-coagulation sludge recycled to a flocculation tank enabled the reduction of a dose of low basicity PACl by 15% compared to a dose required in conventional coagulation. In periods of coagulant overdosing, sludge addition prevented an increase in the number of fine particles in an outflow from sedimentation tanks that could not be retained in a filter bed.
Research Article|May 17 2016
Application of recycled sludge to stabilize coagulation process
Jolanta Gumińska, Adam Gumiński; Application of recycled sludge to stabilize coagulation process. Water Science and Technology: Water Supply 1 December 2016; 16 (6): 1571–1579. doi: https://doi.org/10.2166/ws.2016.083
Download citation file:
Don't already have an account? Register
You could not be signed in. Please check your email address / username and password and try again.