AWWA ACE59825

This paper describes the results of a pilot-scale Actiflo® waste treatment investigation conductedat the City of Calgary's Glenmore Water Treatment Plant (WTP) from April to June 2003. Inaddition to Actiflo pilot testing, a pilot-scale clarifier-thickener was used to evaluate sludgethickening. The clarifier-thickener consisted of a flocculation tank followed by an integrated tubesettler unit located above a gravity sludge thickener. Performance of the clarifier-thickener wasexcellent. At a surface loading rate of 5.6 m/h, solids content in the thickened sludge ranged from1% with no polymer addition to 9% with the addition of 0.5 mg/L of anionic polymer. Thickenersupernatant ranged from 1-4 NTU, depending on polymer dose.The dewaterability of the thickened sludge was also examined as part of this study. Sludge fromthe clarifier-thickener was sent offsite for bench-scale centrifuge and plate filter press tests.Dewatered cake solids ranged from 20-40% from the centrifuge tests, using an anionic polymerwith the centrifuge. It was found that the ease of dewatering was affected by the polymer doseadded in the thickener-clarifier. In some instances, excessive polymer doses in the thickener-clarifierresulted in poor sludge dewaterability, and low final solids content. Bench-scale plate filterpress tests resulted in dewatered cake solids in the range of 20-40%. Best results with the filterpress were seen with the addition of lime and polymer to the thickened sludge. Includes tables, figures.

Product Details

Edition:

Vol. - No.

Published:

06/17/2004

Number of Pages:

11

File Size:

1 file , 380 KB