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Medium Preparation for the Cultivation of Microorganisms under Strictly Anaerobic/Anoxic Conditions
Published on: August 15, 2019
Advanced nitrogen removal without addition of external carbon source in an anaerobic/aerobic/anoxic sequencing batch
Liangliang Shi1, Bin Ma1, Xiyao Li1
1National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, No. 100 Ping Le Yuan, Chaoyang District, Beijing, 100124, People's Republic of China.
Abstract:
Advanced nitrogen removal without the addition of external carbon source is challenging in the conventional biological nitrogen removal processes. This study presented a novel anaerobic/aerobic/anoxic sequencing batch reactor (A/O/A SBR) based on endogenous nitrate (NO3--N) respiration to enhance nitrogen removal. The mean effluent total nitrogen (TN) in the A/O/A SBR could be reduced to as low as 3.5 mg/L, when the average influent TN and chemical oxygen demand (COD) were 52.7 and 235.4 mg/L, respectively. This advanced nitrogen removal was attributed to the post-denitrification, since 82.7% of TN removal was achieved in the post-anoxic stage. The post-denitrification rate with nitrite (NO2--N, 0.59 mg NO2--N/gMLVSS/h) was higher than that with NO3--N (0.35 mg NO3--N/gMLVSS/h). Therefore, the post-anoxic time could be further optimized by achieving denitrification via NO2--N. The A/O/A SBR has good potential in achieving advanced nitrogen removal, especially in nitrogen-sensitive rural areas.
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