Effect of sludge redistribution strategy on stability of partial nitrification-anammox process: Further exploration of the potential value of sludge

• Published in: Chemosphere (Oxford) 2024-05, Vol.355, p.141707-141707, Article 141707
• Main Authors: Wang, Peng, Ou, Rui, Tan, Jun, Li, Ning, Zheng, Min, Jin, Qinghai, Yu, Jin, He, Di
• Format: Article
• Language: English
• Subjects: High-throughput sequencing analysis; Landfill leachate; Partial nitrification-anammox (PN/A); Quantitative PCR (qPCR); Sludge re-distribution
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2024.141707

The stability of the two-stage partial nitrification-anammox (PN/A) system was compromised by the inappropriate conversion of insoluble organic matter. In response, a sludge redistribution strategy was implemented. Through the redistribution of PN sludge and anammox sludge in the two-stage PN/A system, a transition was made to the Anammox-single stage PN/A (A-PN/A) system. This specific functional reorganization, facilitated by the rapid reorganization of microbial communities, has the potential to significantly decrease the current risk of suppression. The results of the study showed that implementing the sludge redistribution strategy led to a substantial enhancement in the total nitrogen removal rate (TNRR) by 87.51%, accompanied by a significant improvement of 34.78% in the chemical oxygen demand removal rate (CRR). Additionally, this approach resulted in a remarkable two-thirds reduction in the aeration requirements. High-throughput sequencing revealed that the strategy enriched anammox and ammonia-oxidizing bacteria while limiting denitrifying bacteria, as confirmed by quantitative polymerase chain reaction analysis. Furthermore, the principal component analysis revealed that the location and duration of aeration had direct and indirect effects on functional gene expression and the evolution of microbial communities. This study emphasizes the potential benefits of restructuring microbial communities through a sludge redistribution strategy, especially in integrated systems that encounter challenges with suppression. [Display omitted] •The subject of treatment is the landfill leachate after biochemical treatment.•Insoluble organic matter indirectly inhibits the two-stage PN/A system.•Compared to PN/A, A-PN/A improves TNRR by 87.51% and saves 2/3 of aeration volume.•Sludge redistribution strategy contributes to AOB and AnAOB enrichment.•A-PN/A is unfavorable for DB enrichment, but CRR was improved by 34.78%.