Mainstream deammonification at ambient temperature treating real sewage by a plug-flow fixed-bed reactor based on zeolite/tourmaline-modified polyurethane carriers

• Published in: Bioresource technology 2023-09, Vol.384, p.129184-129184, Article 129184
• Main Authors: Li, Yuqi, Liang, Hong, Cheng, Lang, Yang, Wenbo, Wang, Peng, Gao, Dawen
• Format: Article
• Language: English
• Subjects: ambient temperature; Ammonium Compounds; anaerobic ammonium oxidation; Biofilm; Bioreactors - microbiology; cryoprotectants; Denitrification; Mainstream deammonification; nitrites; Nitrogen; Novel carriers; Oxidation-Reduction; Plug flow reactor; polysaccharides; Polyurethanes; Real domestic sewage; secretion; sewage; Sewage - microbiology; sewage treatment; technology; Temperature; Thauera; water quality; Zeolites
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2023.129184

[Display omitted] •Efficient mainstream deammonification at 16.8–19.7 °C was achieved in PFBRZTP.•Anammox dominated nitrogen removal in PFBRZTP with a higher contribution of 64.0 %.•PFBRZTP was affected less by pretreatment performance and operational parameters.•lower PN/PS indicated a better biofilm structure in PFBRZTP treating real sewage.•Partial denitrification was an important nitrite supply for Anammox in PFBRZTP. A plug-flow fixed-bed reactor (PFBR) with zeolite/tourmaline-modified polyurethane (ZTP) carriers (PFBRZTP) was constructed to realize mainstream deammonification for real domestic sewage treatment. The PFBRZTP and PFBR were operated for 111 days treating aerobically pretreated sewage in parallel. A higher nitrogen removal rate of 0.12 kg N·(m3·d)−1 was achieved in PFBRZTP despite lowering the temperature (16.8–19.7 °C) and fluctuating water quality. Meanwhile, it was indicated that anaerobic ammonium oxidation dominated (64.0 ± 13.2%) in PFBRZTP, by nitrogen removal pathway analysis and high anaerobic ammonium-oxidizing bacteria (AnAOB) activity (2.89 mg N·(g VSS·h)−1). And, the lower protein/polysaccharides (PS) ratio further indicated a better biofilm structure in PFBRZTP owing to a higher abundance of microorganisms relevant to PS and cryoprotective EPS secretion. Furthermore, partial denitrification was an important nitrite supply process in PFBRZTP based on low AOB activity/AnAOB activity ratio, higher Thauera abundance and a remarkably positive correlation between Thauera abundance and AnAOB activity.