AWWA ACE70650

This powerpoint presentation begins by providing a brief overview of arsenic contamination, and alternative processes for removing arsenic. The advantages of iron preloaded granular activated carbon (GAC) are presented, along with experimental set-up that consisted of iron tailored GAC tested in rapid small-scale column tests (RSSCTs) and pilot-scale trials at Penn State. Pilot columns, electrolytic cell, branched iron rods, and laboratory columns are presented, along with conclusions that indicate the following: in RSSCT testing, the temperature of iron precuring (60-100ºC) made little difference; RSSCT and pilot column results agreed closely (RSSCT designed via proportional diffusivity); the branched rod configuration with higher surface area worked more effectively than straight rods that had less surface area; combining rods with iron tailored GAC provided effective As removal at start-up; the most effective system combined branched iron rods with Fe-GAC, extending BV of 10 ppb As to 43,000 BV; electrolytic cells were effective for As removal but columns experienced pressure and voltage buildup; and, effluent iron < 0.2 mg/L for all runs, except when rods extend to media bottom. Includes tables, figures.