Implementing a completely autotrophic nitrogen removal over nitrite process using a novel umbrella basalt fiber carrier

• Published in: Water science and technology 2024-07, Vol.90 (1), p.270-286
• Main Authors: Li, Shan-Wei, Xu, Wei, Xie, Yu-Jie, Fu, Liang, Gao, Qi, Wang, Xiao-Chun, Li, Yan, Wu, Zhi-Ren
• Format: Article
• Language: English
• Subjects: anammox; Autotrophic Processes; Bacteria - metabolism; Bioreactors; canon; Nitrites - chemistry; Nitrogen - chemistry; nitrogen removal; partial nitrification; umbrella basalt fiber carrier; Waste Disposal, Fluid - methods
• ISSN: 0273-1223; 1996-9732
• DOI: 10.2166/wst.2024.188

The completely autotrophic nitrogen removal over nitrite (CANON) process is significantly hindered by prolonged start-up periods and unstable nitrogen removal efficiency. In this study, a novel umbrella basalt fiber (BF) carrier with good biological affinity and adsorption performance was used to initiate the CANON process. The CANON process was initiated on day 64 in a sequencing batch reactor equipped with umbrella BF carriers. During this period, the influent NH -N concentration gradually increased from 100 to 200 mg·L , and the dissolved oxygen was controlled below 0.8 mg L . Consequently, an average ammonia nitrogen removal efficiency (ARE) and total nitrogen removal efficiency (TNRE) of ∼90 and 80% were achieved, respectively. After 130 days, ARE and TNRE remained stable at 92 and 81.1%, respectively. This indicates a reliable method for achieving rapid start-up and stable operation of the CANON process. Moreover, and were identified as dominant anammox genera on the carrier. was the predominant genus among ammonia-oxidizing bacteria. Spatial differences were observed in the microbial population of umbrella BF carriers. This arrangement facilitated autotrophic nitrogen removal in a single reactor. This study indicates that the novel umbrella BF carrier is a highly suitable biocarrier for the CANON process.