AWWA ACE54495

This work was designed to determine if sand ballasted coagulation is a viable means of removing arsenic from drinking water in response to the forthcoming regulation. A jar test protocol was developed and tested on a wide range of waters to compare the relative effectiveness of microsand ballasted coagulation and other coagulation based treatment processes in arsenic removal. Secondary impacts of the microsand process such as residual turbidity, iron, membrane filter run length and total organic carbon (TOC) removal were also considered as part of this evaluation. In terms of arsenic removal, microsand ballasted coagulation provided promising results for many of the simulated groundwater test conditions, in which more than 80% of the arsenic regulation costs will be incurred. No synergistic benefits were typically observed when using microsand ballasted coagulation as a pretreatment to microfiltration. The addition of polymer was also examined and found to be critically important to the performance of the microsand ballasted coagulation process. Furthermore, it was discovered that rapid mixing of new microsand released fines that added to the turbidity of the water. However, after the initial release, very few additional fines were detached and this is not expected to be a problem in practice. Includes 7 references, table, figures.

Product Details

Edition:

Vol. - No.

Published:

06/01/2001

Number of Pages:

19

File Size:

1 file , 350 KB