Nitrogen removal performance and rapid start-up of anammox process in an electrolytic sequencing batch reactor (ESBR)

• Published in: Chemosphere (Oxford) Vol. 308; p. 136293
• Main Authors: Lu, Yuyu, Wang, Juanting, Feng, Yan, Li, Honglan, Wang, Zhongwei, Chen, Hao, Suo, Ning, Yu, Yanzhen, Shoubin Zhang
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2022
• Subjects: Anaerobic ammonia oxidation; Current density; Electrolytic sequencing batch reactor; Nitrogen removal performance; Rapid start-up; Nitrogen removal performance; Rapid start-up; Electrolytic sequencing batch reactor; Anaerobic ammonia oxidation; Current density
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2022.136293

In this study, the electrolytic sequencing batch reactor (ESBR) with different current densities was constructed to investigate the nitrogen removal performance and rapid start-up of anaerobic ammonia oxidation (anammox) process. The changes of total nitrogen removal rate (TNRR), specific anammox activity (SAA) and nitrogen concentration under different current densities were analyzed, and then the effect of the optimal current density on the start-up of anammox in ESBR was explored. The results showed that ammonium nitrogen removal efficiency (92.7%), nitrite nitrogen removal efficiency (15.5%) and total nitrogen removal efficiency (28.1%) were obtained with the TNRR and SAA were 0.0118 g N L−1 d−1 and 0.0050 g N (g Vss d)−1, respectively under the optimal conditions (i.e., current density = 0.10 mA cm−2, temperature = 36 °C and pH = 7.6). In addition, the stoichiometric ratio indicated that anammox was initiated successfully for 91 days in ESBR with the current density of 0.10 mA cm−2, which was shortened by 10 days compared with the conventional SBR without current density. These results suggest that an array of rapid start-up processes of anammox can be developed through applying current density to stimulate the activity of anammox bacteria (AnAOB). [Display omitted] •ESBR with appropriate current density enhanced the nitrogen removal performance.•The start-up time of anammox process was shortened by applying ESBR with appropriate current density.•Positive effect of iron anode as electrode on AnAOB.•A hypothetical mechanism of synergistic nitrogen removal by electrochemical oxidation and anammox.