AWWA WQTC65874

This powerpoint presentation outlines a pilot scale filter study at the Greene County, Ohio, South Plant. A brief overview of background information is provided, including: more than half (28 µg/L) of the arsenic enteringfilter is soluble;more than half (23 µg/L) of the arsenic enteringthe filter is in As(III) form;unexpected and unexplained removal of arsenicthrough filter, no strong oxidant;As(V) dominates filter effluent; and,complete nitrification takes place in filter. Objectives of the study included: determine what was happening to the arsenic in the filter; determine theimpact of replacing existing filter media onarsenic removal and ammonia oxidation; and, determine the best way to bring new filters on-line toachieve previous biological activity. Key pilot study conclusions:microbiological accumulation and complete nitrification(NH3 - NO3) was achieved in all pilot filters by 71 days;no significant difference between methods of seedingcolumns;significant oxidation of As (III) to As (V) occurs duringfiltration (greater than 80% of soluble As (III) ) shortlyafter start-up;filtration removes greater than 75% of total arsenic(presumably by iron adsorption of As [V]);residual arsenic is predominantly in the form ofsoluble As (V); and,iron was effectively removed by pilot system at start-up. Includes tables, figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2007

Number of Pages:

23

File Size:

1 file , 1000 KB