title: Nitrate-contaminated groundwater remediation by combined autotrophic and heterotrophic denitrification for sulfate and pH control: batch tests.
abstract: Groundwater remediation was evaluated for combined autotrophic and heterotrophic denitrification under high (154 mg/L as CaCO3) and low (95 mg/L as CaCO3) alkaline conditions. Two levels of acetate (47 and 94 mg/L) and ethanol (24 and 48 mg/L) were added to the reactors. Obtained denitrification rates were 2.89, 2.58, 3.55, 1.96, and 2.0 mg-N/L · h for high alkaline conditions, whereas under low alkaline conditions has given 2.36, 1.94, 2.47, 2.74, and 2.29 mg-N/L · h for control, 47 and 94 mg/L acetate, and 24 and 48 mg/L ethanol, respectively. Nitrite was accumulated for controls but reactors with acetate and ethanol did not accumulate nitrite. Acetate and ethanol addition decreased sulfate to nitrate ratios in the range of 4.5-7.58 for high alkaline conditions (12.77 for control) and 4.43-6.78 for low alkaline conditions (7.90 for control). Acetate was more efficient compared with ethanol in controlling sulfate production and pH maintenance.
authors.affiliation: Department of Biological Environment, Kangwon National University, Chuncheon, Kangwon-do, Republic of Korea.
authors.forename: Naveed Ahmed
authors.initials: NA
authors.lastname: Qambrani
authors.forename: Sokhee
authors.initials: S
authors.lastname: Jung
authors.forename: Suk Hee
authors.initials: SH
authors.lastname: Jung
authors.forename: Yong Sik
authors.initials: YS
authors.lastname: Ok
authors.forename: Yong Seong
authors.initials: YS
authors.lastname: Kim
authors.forename: Sang-Eun
authors.initials: SE
authors.lastname: Oh
mesh_terms: D052818:Autotrophic Processes; D001673:Biodegradation, Environmental; D058440:Denitrification; D052918:Environmental Restoration and Remediation / Q000379:methods*; D060587:Groundwater / Q000737:chemistry*; D052836:Heterotrophic Processes; D006863:Hydrogen-Ion Concentration; D009566:Nitrates / Q000032:analysis / Q000378:metabolism; D009573:Nitrites / Q000032:analysis / Q000378:metabolism; D013431:Sulfates / Q000032:analysis* / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*
chemical_list: D009566:Nitrates; D009573:Nitrites; D013431:Sulfates; D014874:Water Pollutants, Chemical