AWWA JAW68771

Arsenic removal was characterized at 31 ironremoval plants in Illinois representative of manysimilar facilities in the upper Midwest. The plantsused different iron removal processes and had awide range of arsenic, iron, and total organic carbonconcentrations.Iron concentration in raw water is an importantfactor in arsenic removal. Removal of arsenic dependson oxidation of arsenite to arsenate, adsorption ofarsenic to hydrous ferric oxide (HFO), and filtration toremove HFO and any adsorbed arsenic. In the currentwork, soluble arsenic concentrations were lowered byat least 75% when the iron concentration of the rawwater was > 3 mg/L Fe.In both models of soluble arsenic removal developedin this research, adsorption to HFO was assumedto be the only reaction that removes arsenic from solution.A generalized double-layer model generallyunderpredicted arsenic removal, whereas a parametricmodel that was consistent with surface complexationand accounted for the effects of other adsorbing substances,fit the data fairly well. Includes 54 references, tables, figures.

Product Details

Edition:

Vol. 100 - No. 9

Published:

09/01/2008

Number of Pages:

12

File Size:

1 file , 560 KB