AWWA WQTC50487

Untreated colored groundwater from a regional well in Orange County was pumped to an ozone treatment plant for color removal by a booster pump at a rate of 3,000 gallons-per-minute (GPM). Ambient air was used as the feed gas to four ozone generators, and each generator produced 250 pounds of ozone on site per day. The applied ozone dose was 10 mg/L. At the operational flow rate of 3,000 gpm, the hydraulic residence time was 15 minutes. In an effort to remove assimilable organic carbon (AOC) formed during ozone oxidation, biologically-active filtration (BAF) was evaluated. A side stream (50 to 150 gpm) of ozone-treated colored groundwater fed a pilot-scale gravity BAF filter containing mainly granular activated carbon (GAC) as filter medium. GAC medium sits on top of a thin layer of coarse sand which serves the purpose of supporting medium to the GAC. The backwash cycle of gravity BAF filter consists of water and air scour, and can be done manually or automatically (in terms of time interval or head loss readings). The frequency of filter backwashing for this project was based primarily on head loss readings. Includes 12 references.

Product Details

Edition:

Vol. - No.

Published:

01/01/1999

File Size:

1 file , 200 KB