Nitrogen removal performance and bacterial community in a full-scale modified Orbal oxidation ditch with internal nitrate recycle and biocarriers. (April 2021)

• Record Type: Journal Article
• Authors: Wang, Xianbao; Gao, Chuyue; Jin, Pengkang; Zhang, Yudi; Xie, Yili; Chen, Tiantian; Zhang, Anlong
• Is Part Of: Journal of water process engineering. Volume 40(2021)
• Publication Date: 2021-04
• Subjects: Orbal oxidation ditch -- Nitrogen removal -- Biocarrier -- Microbial community composition -- Internal recycle; Water-supply engineering -- Periodicals; Saline water conversion -- Periodicals; Seawater -- Distillation -- Periodicals; Sanitary engineering -- Periodicals; Sewage -- Purification -- Periodicals; 627
• DOI: 10.1016/j.jwpe.2020.101791
• Languages: English
• ISSNs: 2214-7144

Abstract

Graphical abstract: Highlights: NH4 + -N removal in Orbal oxidation ditch was improved by adding biocarriers. TN removal efficiency increased from 68.7%–76.5% by implementing internal recycle. Microbial community in different channels of Orbal oxidation ditch was similar. Nitrifying bacteria were enriched in biocarriers. Abstract: A modified Orbal oxidation ditch with biocarriers and internal nitrate recycle was used in a full-scale municipal wastewater treatment plant, and nitrogen removal performance and microbial community were investigated. The results indicated that ammonia nitrogen removal efficiency increased from 80.5% to 95.4% after increasing oxygen supply and adding biocarriers in inner channel, and biocarriers played an important role in ammonia nitrogen removal. Internal recycle could enhance total nitrogen (TN) removal in outer channel, with TN removal efficiency of modified Orbal oxidation ditch reaching 76.5 %, which was higher than that of the traditional Orbal oxidation ditch (68.7 %). The pyrosequencing results revealed that bacterial community of the activated sludge in inner, middle and outer channels were very similar, but differed to that of the biofilm. The relative abundance of Nitrospira was 15.3 % in biofilm and less than 1.5 % in activated sludge. Nitrospira was enriched in the biofilm, thereby ammonia nitrogen removal was enhanced.