AWWA ACE99545

The objective of this study was to evaluate the steady-state adsorption process when powdered activated carbon (PAC) was applied to a floc blanket reactor (FBR) for the removal of the pesticide atrazine in the presence of natural organic matter (NOM). A laboratory-scale upflow FBR was used to investigate the operating conditions affecting adsorption of atrazine by various PAC doses. The effects of carbon dose and hydraulic loading rate on carbon retention times were also investigated. Continuous-flow experiments were conducted using a laboratory-scale FBR. The influent water, which contained a dissolved organic carbon concentration of 2.1 mg/L, was spiked with atrazine to maintain a steady-state concentration of 2.0 ug/L. Atrazine removals were evaluated for three carbon doses (2, 4 and 8 mg/L). PAC accumulation in the blanket and the resulting carbon retention times were evaluated for various operating conditions, including various hydraulic loading rates, blanket depths and PAC doses. Adsorption isotherms and kinetic tests were performed in raw and coagulated groundwater to evaluate the effect of coagualtion on atrazine adsorption. Model predictions were compared with experimental data and the applicability of this approach in continuous-flow adsorption systems was discussed.

Product Details

Published:

01/01/1999

ISBN(s):

1583210016

Number of Pages:

4

File Size:

1 file , 140 KB