Arsenic/Iron Removal from Groundwater with Elevated Ammonia and Natural Organic Matter
Citation:
Chen, A., L. Wang, D. Lytle, AND T. Sorg. Arsenic/Iron Removal from Groundwater with Elevated Ammonia and Natural Organic Matter. JOURNAL OF THE AMERICAN WATER WORKS ASSOCIATION. American Water Works Association, Denver, CO, 110(3):E2-E17, (2018). https://doi.org/10.5942/jawwa.2018.110.0020
Impact/Purpose:
Under the U.S. Environmental Protection Agency Arsenic Demonstration Program, an iron removal (IR) process consisting of permanganate oxidation followed by GreensandPlus™ filtration was shown to be effective in removing soluble As(III) (24.1 μg/L on average) from Waynesville, IL ground water, which also contained elevated ammonia (3.8 mg N/L on average) and natural organic matter (NOM) (7.9 mg/L of total organic carbon on average). Chlorine was not the choice of oxidant because it reacts with ammonia to form chloramines, which are not as effective in oxidizing As(III). Using permanganate, a treatment strategy was developed to overcome NOM effects, which exerted additional demand on permanganate. The IR system was kept as a closed system to ensure simultaneous oxidation of soluble As(III) and soluble Fe(II) and prevent nitrification. Compliance monitoring to date shows consistent removal of arsenic to below 4 µg/L in finished water since the commencement of system operation in 2009.
Description:
Under the U.S. Environmental Protection Agency Arsenic Demonstration Program, an iron removal (IR) process consisting of permanganate oxidation followed by GreensandPlus™ filtration was shown to be effective in removing soluble As(III) (24.1 μg/L on average) from Waynesville, IL ground water, which also contained elevated ammonia (3.8 mg N/L on average) and natural organic matter (NOM) (7.9 mg/L of total organic carbon on average). Chlorine was not the choice of oxidant because it reacts with ammonia to form chloramines, which are not as effective in oxidizing As(III). Using permanganate, a treatment strategy was developed to overcome NOM effects, which exerted additional demand on permanganate. The IR system was kept as a closed system to ensure simultaneous oxidation of soluble As(III) and soluble Fe(II) and prevent nitrification. Compliance monitoring to date shows consistent removal of arsenic to below 4 µg/L in finished water since the commencement of system operation in 2009.
URLs/Downloads:
DOI: Arsenic/Iron Removal from Groundwater with Elevated Ammonia and Natural Organic MatterFree access through PubMed Central