Combined effect of pre-chlorination and coagulant addition on turbidity removal of the clarification water in water treatment plant by sludge blanket clarifier
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Abstract
This paper aims to study performance of turbidity removal of the clarification water in water treatment plant by sludge blanket clarifier. By controlling coagulant dosing rate, the results between pre-chlorination and no pre-chlorination addition on turbidity removal efficiency of the clarifier were compared. Experimental results found that the pre-chlorination addition was significantly affected on turbidity removal efficiency for the clarification water. The pre-chlorination addition provided higher turbidity removal efficiency than the no pre-chlorination addition. For, the pre-chlorination addition, turbidity removal efficiency was 86.3% ±1.7%. For the no pre-chlorination addition turbidity removal efficiency was 81.5% ±2.8%. Because of the pre-chlorination addition showed higher a decreased pH than the no pre-chlorination addition. The increasing in residual chlorine from the clarified water enhanced increasing of turbidity removal efficiency in polynomial relation. At a 18-mg/l alum dosage, the optimum residual chlorine from the clarified water was in range 0.12-0.16 mg/l which provided highest turbidity removal efficiency. The optimum residual chlorine enhanced turbidity removal efficiency about 2.7% ±1%.
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References
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