Assessing Coagulant Dosage in Full-Scale Drinking Water Treatment Plants Using Nephelometry

摘要

A nephelometric turbidimeter monitoring system (NTMS) was utilized to measure the standard deviationn(SD) of turbidity of suspension solutions. Experimental results demonstrated that turbidity SD was consistentnwith the theory that underlay the ‘‘turbidity fluctuation technique.’’ The NTMS was also used at anfull-scale drinking water treatment plant to continuously monitor turbidity in all flocculation tanks. Experimentalnresults revealed that under coagulant dosages of 0.33, 0.92, 1.67, and 2.67mg/L, turbiditynSD was strongly correlated with floc diameter in the flocculation tank. Turbidity SD and floc diameternincreased to their maximum values at a coagulant dosage of 0.92mg/L. This result suggested that turbiditynSD obtained by using an NTMS could be used to determine the operational important parameters ofnwater treatment plants.