Performance and microbial community analysis of Combined Denitrification and Biofloc Technology (CDBFT) system treating nitrogen-rich aquaculture wastewater. (September 2019)

• Record Type: Journal Article
• Authors: Li, Changwei; Li, Jiawei; Liu, Gang; Deng, Yale; Zhu, Songming; Ye, Zhangying; Shao, Yufang; Liu, Dezhao
• Is Part Of: Bioresource technology. Volume 288(2019)
• Publication Date: 2019-09
• Subjects: Denitrification -- Biofloc technology -- Aquaculture wastewater -- LED light -- Microbial community; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2019.121582
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Newly Combined Denitrification and Biofloc Technology (CDBFT) system was established. SND was achieved with TN mainly removed via denitrification rector. High DOC from denitrification effluent was used to feed the biofloc. Blue light helped to remove nitrate due to algae-denitrifying bacterial symbiosis. Rotifera and Nematoda only presented in biofloc reactor when under light. Abstract: This study proposed two novel Combined Denitrification and Biofloc Technology (CDBFT) systems (one under blue LED light (L1) and the other without light (C1), each containing a denitrification (DE) reactor and a biofloc-based reactor) for the enhanced total nitrogen (TN) removal. Long-term operation (110 days) suggested that simultaneous nitrification and denitrification was achieved in both C1 and L1. Significantly higher total nitrogen removal efficiency (TNRE) was observed in L1-CDBFT (92.2%) than C1-CDBFT (87.5%, P < 0.05; after day 14). Further 24-hour nitrogen transformation test showed the boosted nitrate removal of L1-BFT than C1-BFT. High-throughput sequencing analysis revealed that phyla Rotifera and Nematoda which were indispensable for aquatic animal larviculture, were only found in L1-BFT. Nevertheless, CDBFT effluent from both systems was suitable for tilapia culture based on water quality, biofloc characteristics and tilapia survival rates. Overall, this study highlights the significance of developing CDBFT for TN removal especially under lights.