Research
Title: | Nitrate removal from low carbon-to-nitrogen ratio wastewater by combining iron-based chemical reduction and autotrophic denitrification |
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First author: | Liu, Xiawei; Huang, Manqi; Bao, Shaopan; Tang, Wei; Fang, Tao |
Journal: | BIORESOURCE TECHNOLOGY |
Years: | 2020 |
DOI: | 10.1016/j.biortech.2019.122731 |
Abstract: | Nitrate removal from low carbon-to-nitrogen ratio (C/N) wastewater has always been a knotty problem due to the deficiency of organics. Here, a novel iron-based chemical reduction and autotrophic denitrification (ICAD) system was developed. ICAD system could maintain average nitrate removal efficiency of 97.2% for 131 days with feeding 20.3 mg NO3--N/L at hydraulic retention time (HRT) of 24 h. The optimal operational conditions was further explored, and results demonstrated that average nitrate removal efficiency of 85.5% and 98.4% could be achieved at HRT of 12 h and 24 h (influent 20.3 mg NO3--N/L), while average nitrate removal efficiency could reach 96.3% at optimal HRT of 12 h (influent 10.3 mg NO3--N/L). Hydrogenophaga, which can carry out hydrogenotrophic denitrification, showed a positive correlation with nitrate removal efficiency of the ICAD system. Low cost and simple operation make the ICAD system suitable for large-scale application. |