AWWA ACE68980

The objectives of this poster session were to use bench-scale jar tests to develop treatment strategies that produce finished water capable of meeting existing and anticipated water quality regulations. Preliminary jar tests were performed to determine the target coagulant/polymer dose and type when used alone and when combined with oxidative pretreatment by chlorine dioxide, sodium permanganate, a combination of chlorine dioxide and sodium permanganate, and ozone. Pretreatment with powdered activated carbon (PAC) was also evaluated for removal of organics. The jar tests and bench scale tests yielded the following conclusions: ferric chloride coagulant was more effective than alum or ACH for organics removal; chemical pretreatment (e.g.chlorine dioxide and sodium permanganate) did not influence the removal of organics or target coagulant dose, but pretreatment is likely necessary for the control of taste and odor and/or iron and manganese; conventional treatment that consists of chemical pretreatment with chlorine dioxide or sodium permanganate, clarification using optimum enhanced coagulation, and use of free chlorine for primary and secondary disinfection resulted in disinfection byproduct (DBP) formation above regulatory levels for some raw water conditions; and, use of chloramines instead of free chlorine for secondary disinfection resulted in much lower DBP formation that complied with regulatory levels.

Product Details

Edition:

Vol. - No.

Published:

11/01/2008

Number of Pages:

1

File Size:

1 file , 26 MB