Multiple draft tubes airlift loop membrane bioreactor as an efficient system for acidic 7-amino cephalosporanic acid (7-ACA) wastewater treatment. (May 2020)

• Record Type: Journal Article
• Authors: Hu, Dongxue; Zhao, Yuanyi; Wang, Hongcheng; Min, Hongchao; Cui, Yubo; Luo, Kongyan; Zhang, Lufeng; Liu, Wenyu; Zhang, Ying
• Is Part Of: Bioresource technology. Volume 304(2020)
• Publication Date: 2020-05
• Subjects: Multiple draft tubes airlift loop membrane bioreactor (Mt-ALMBR) -- Acidic 7-amino cephalosporanic acid (7-ACA) wastewater -- Adsorption -- Enzymatic activity; 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.2020.123014
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Acidic 7-ACA wastewater was direct treated by Mt-ALMBR without pH adjustment. Mt-ALMBR showed good removals on COD, BOD5 and 7-ACA at low pH (3.54–6.20). pH affected enzymatic activity and capacity of sludge to adsorb 7-ACA significantly. The mathematical models for 7-ACA removal rate and pH were calculated. Abstract: In this study, a lab-scale multiple draft tubes airlift loop membrane bioreactor (Mt-ALMBR) was used for treating acidic 7-amino cephalosporanic acid (7-ACA) wastewater under different pHs (3.54–6.20) and hydraulic retention time (HRT) (48 h, 36 h, 24 h and 16 h). During about 200 days operation, under HRT of 48 h and pH condition about 6.0, the optimum average COD and BOD5 removal rates were reach to 84.4 ± 2.1% and 94.9 ± 0.8%, and the highest 7-ACA removal rate also observed as 77.6%. Biodegradation, membrane rejection, hydrolysis and sludge adsorption were the four main pathways of 7-ACA removal. With the increase of pH, biodegradation, membrane rejection and hydrolysis had significant positive impacts on 7-ACA removal, while adsorption had a negative impact. Moreover, mathematical models for 7-ACA removal rate and pH were calculated to guide the operation of Mt-ALMBR. Biodegradation was the main pathway to remove 7-ACA when pH was >4.17.