Enhancing completely autotrophic nitrogen removal over nitrite by trace NO2 addition to an AUSB reactor

✍ Scribed by Daijun Zhang; Qing Cai; Liying Cong

• Book ID: 102315493
• Publisher: Wiley (John Wiley & Sons)
• Year: 2009
• Tongue: English
• Weight: 119 KB
• Volume: 85
• Category: Article
• ISSN: 0268-2575
• DOI: 10.1002/jctb.2288

✦ Synopsis

Abstract

BACKGROUND: Completely autotrophic nitrogen removal over nitrite (CANON) could decrease energy consumption and CO~2~ release compared with conventional nitration–denitrification. Trace NO~2~ addition could enhance the activities of aerobic and anaerobic ammonium oxidation.

RESULTS: An aerated upflow sludge bed (AUSB) reactor inoculated simultaneously with aerobic and anaerobic ammonium oxidizing sludge was operated to cultivate granular sludge capable of carrying out CANON. The results showed that the efficiency and rate of total nitrogen (TN) removal reached 61% and 0.114 kgN, respectively (m^−3^ day^−1^) for DO = 0.5–0.6 mg L^−1^. Batch tests indicated that trace NO~2~ addition could increase the CANON activity of sludge. The TN removal rate and efficiency of the reactor was increased to 0.234 kgN m^−3^ day^−1^ and 63%, respectively, when the reactor was aerated with air containing 2.7–3.3 mmol m^−3^ NO~2~ and DO was at 0.5–0.8 mg L^−1^.

CONCLUSIONS: Trace NO~2~ addition provides an alternative to increase the capacity of a CANON system at low DO concentration. Copyright © 2009 Society of Chemical Industry