Efficient partial nitrification with hybrid nitrifying granular sludge based on a simultaneous fill/draw SBR mode. (February 2023)

• Record Type: Journal Article
• Authors: Zhao, Kaige; Zhang, Tianyi; Tian, Yixing; Li, Haisong; Wan, Junfeng; Wang, Yan
• Is Part Of: Chemosphere. Volume 313(2023)
• Publication Date: 2023-02
• Subjects: Simultaneous fill/draw SBR -- Partial nitrification -- Ammonia-oxidizing bacteria -- Hybrid granular sludge system; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2022.137579
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: In this study, a simultaneous fill/draw SBR was applied to investigate the feasibility of partial nitrification process with inoculation of matured aerobic granular sludge. The system operated stably over 120 days with the relatively high ammonium removal efficiency (≥ 98.83%) and nitrite accumulation rate (≥ 89.60%). Moreover, a hybrid flocs/granules system was formed stably after long-term operation. The nitrite-oxidizing bacteria (NOB) was suppressed effectively because of the combined effect of simultaneous fill/draw mode and intermittent aeration conditions. Furthermore, batch tests were separately tested with isolated granules (> 200 μm) and flocs (< 200 μm), showing that the specific ammonia oxidation rate of granules and flocs were 15.94 ± 2.85 and 66.77 ± 0.83 mg N/(g MLSS·h), respectively. Correspondingly, the abundance of Nitrosomonas as a typical AOB in granules (6.24%) and flocs (11.94%) was obtained via the microbial diversity analysis, while NOB was almost hardly detected in granules and flocs. Graphical abstract: Image 1 Highlights: SFD-SBR system was applied for the first time to achieve partial nitrification. NAR above 80% maintained stably with hybrid sludges over 90 days in SFD-SBR. The various abundance of AOB existed in flocs (11.94%) and granules (6.24%). NOB was inhibited by combined effect of intermittent aeration and fill/draw mode.