Abstract:[Objective] Understanding the characteristics of simultaneous carbon and nitrogen removal under different conditions. [Methods] We took strain Y5, which was isolated in the medium with sodium acetate as the sole carbon source and capable of removing carbon and nitrogen simultaneously, as the model microorganism in this study. The 16S rRNA gene sequence of strain Y5 was analyzed. The carbon and nitrogen removal dynamics of strain Y5, as well as the influencing factors such as carbon source, ratio of carbon to nitrogen (C/N), dissolved oxygen concentration (DO), temperature, and pH were investigated. [Results] Strain Y5 belonged to Alcaligenes faecalis. Compared with glucose and other organic acids, strain Y5 showed higher total organic carbon (TOC) and NH4+-N removal rates in the medium with sodium acetate as the sole carbon source. When the initial TOC and NH4+-N were 1 000 mg/L and 110 mg/L, the NH4+-N, TOC and TN removal rates were 99.54%, 92.95% and 86.55% after 48 hours aerobic incubation, respectively. [Conclusion] Alcaligenes faecalis Y5 had efficient carbon and nitrogen simultaneous removal ability when taking sodium acetate as the sole carbon source and its optimal conditions were C/N=10, pH 7?8, DO>6.20 mg/L, 30 °C.
