Permeable Reactive Barrier For Arsenic Removal From Arsenic Groundwater
Investigations were undertaken to study arsenic (As) removal from arsenic groundwater using fly ash (FA), bottom ash (BA), and bentonite clay (BC). Toxicity characteristic leaching procedure (TCLP) reveals that fly ash, bottom ash, and bentonite claycontained heavy metals such as Manganese (Mn), Copper (Cu), Zinc (Zn), Arsenic (As), and lead (Pb). Continuous column test with fly ash, bottom ash, and bentonite clay showed negligible heavy metal leach-out at neutral pH, except for Zn leached from bentonite clay.Column arsenic removal studies reveals order of arsenic removal using three ratios of reactive material mixturesas ratio of 60% BA, 20% FA, 20% BC mixtures> ratio of 80% BA, 10% FA, 10% BC mixtures> ratio of 100% BA. Removal of arsenic is attributed mainly to sorption due to negatively charged surface of fly ash, bottom ash, and bentonite clay.
Keywords- Arsenic Removal, Permeable Reactive Barrier, Coal Fly Ash, Coal Bottom Ash, Bentonite Clay.