Mixotrophic denitrification processes in basalt fiber bio-carriers drive effective treatment of low carbon/nitrogen lithium slurry wastewater. (November 2022)

• Record Type: Journal Article
• Authors: Ni, Huicheng; Arslan, Muhammad; Liang, Zhishui; Wang, Chencheng; Luo, Zhijun; Qian, Junchao; Wu, Zhiren; Gamal El-Din, Mohamed
• Is Part Of: Bioresource technology. Volume 364(2022)
• Publication Date: 2022-11
• Subjects: Basalt fiber -- Bio-carrier -- Carbon to nitrogen ratio (C/N) -- Nitrogen removal -- Simultaneous nitrification and denitrification (SND); 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.2022.128036
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Efficacy of R-BF was studied for the biological treatment of lithium slurry wastewater. TN removal rate was 4.462 kg/m 3 /d in R-BF while qmax in Monod was 0.32284 mg-N/mgVSS/d. R-BF could regulate diverse nitrogen metabolic pathways to adapt to low C/N ratios. HN-ADs, AOB, NOB and DGAOs were the main functional groups in R-BF. (Aerobic)chemoheterotrophy, nitrogen respiration, and nitrate reduction were dominant processes. Abstract: Lithium battery slurry wastewater was successfully treated by using basalt fiber (BF) bio-carriers in a biological contact oxidation reactor. This resulted in a significant reduction of COD (93.3 ± 0.5 %) and total nitrogen (77.4 ± 1.0 %) at 12 h of HRT and dissolved oxygen (DO) of 0–1 mg/L. The modified Stover-Kincannon model indicated that the total nitrogen removal rate was 4.462 kg/m 3 /d in R-BF while the substrate maximum specific reaction rate ( q max ) in the Monod model was 0.323 mg-N/mgVSS/d. A stable internal environment was established within the bio-nest. Metataxonomic analysis revealed the presence of denitrification and decarbonization bacteria, combined heterotrophic nitrification-aerobic denitrification bacteria, nitrite-oxidizing bacteria, and ammonia-oxidizing bacteria. Functional analysis displayed changes related to (aerobic)chemoheterotrophy, nitrogen respiration, nitrate reduction, respiration/denitrification of nitrite, and nitrate in R-BF. The study proposes a novel approach to achieve denitrification for the treatment of lithium slurry wastewater at low C/N conditions.