AWWA QTC97022

This paper presents the results of a one-year water treatment pilot testing program conducted in Winnipeg, Manitoba, Canada. A dissolved air flotation (DAF) treatment train was compared to direct filtration, for the treatment of a low turbidity, high total organic carbon (TOC) water. The treatment processes were evaluated on the basis of particle and turbidity removal, water production, filter loading rates, disinfection byproduct (DBP) precursor and preformed DBP removal, ozone byproduct formation and reduction, and taste and odor control. DAF loading rates were varied from 10 to 20 m/h (4 to 8 gpm/ft2) with 2 to 3 stage flocculation, and recycle air injection between 6 and 10 mg/L. Deep bed filters and granular activated carbon (GAC) filter/adsorbers were tested at filter loading rates between 15 and 35 m/h (6 to 14 gpm/ft2). Biological filtration was investigated for assimilable organics and ozone byproducts removal. GAC bedlife evaluations were conducted using rapid small scale column tests. Ozonation was assessed for particle removal, taste and odor control, algae control and disinfection. Seasonal raw water temperature ranged from 0.3 to 23 degrees C. The evaluation determined that the DAF design parameters were dictated by the cold water temperatures. The paper focuses on cold water test results used to establish the DAF process design parameters.

Product Details

Published:

01/01/1997

ISBN(s):

0898679583

Number of Pages:

17

File Size:

1 file , 160 KB