Regenerating an Arsenic Removal Iron-Bed Adsorptive Media System, Part 2: Performance and Cost.

Replacement of exhausted, adsorptive media used to remove arsenic from drinking water accounts for approximately 80% of total operational and maintenance costs of this commonly used small system technology. Results of three full-scale system studies of an onsite media regeneration process (discussed in the first article of this two-part series) showed it to be effective in stripping arsenic and other contaminants from a granular ferric oxide (GFO) exhausted adsorptive media. This second article details the performance of the regenerated media to remove arsenic through multiple regeneration cycles and the approximate cost savings of regeneration over media replacement. Results indicated that media regeneration did not appear to have a major detrimental effect on the performance of the GFO media, and the regeneration cost was potentially less than the media replacement cost. Therefore, onsite regeneration offers small systems a possible alternative to media replacement when removing arsenic from drinking water using iron-based adsorptive media technology.