Simultaneous recovery of phosphorus and alginate-like exopolysaccharides from two types of aerobic granular sludge

• Published in: Bioresource technology 2022-02, Vol.346, p.126411-126411, Article 126411
• Main Authors: Chen, Xingyu, Wang, Jixiang, Wang, Qian, Yuan, Tian, Lei, Zhongfang, Zhang, Zhenya, Shimizu, Kazuya, Lee, Duu-Jong
• Format: Article
• Language: English
• Subjects: Aerobiosis; Algal-bacterial aerobic granular sludge; Alginate-like exopolysaccharides; Alginates; Bioreactors; Extracellular polymeric substances; Phosphorus; Phosphorus accumulation; Resource recovery; Sewage; Waste Disposal, Fluid; Waste Water
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2021.126411

[Display omitted] •Simultaneous recovery of P and ALE from two types of granular sludge was attempted.•315.5 mg/g-VSS of EPS was extracted from bacterial AGS.•ALE content in algal-bacterial AGS was more than twice that of bacterial AGS.•Algal-bacterial AGS showed better P recovery potential with 97% of P bioavailability.•70.9% TP in EPS and 0.33 mg/g-SS P in ALE were derived from algal-bacterial AGS. Wastewater treatment plants are expected to realize not only pollutants removal from wastewater but also resources recovery such as phosphorus (P) and alginate-like exopolysaccharides (ALE) from the produced sludge. In this study, ALE extraction and fractionation from the same activated sludge-derived bacterial aerobic granular sludge (AGS) and algal-bacterial AGS were performed in addition to P fate examination during ALE recovery. Results showed that the ALE content recovered from algal-bacterial AGS was 8.81 ± 0.02 mg/g-volatile suspended solids (VSS), about 2.8 times higher than that from bacterial AGS when fed with the same synthetic wastewater. Moreover, the mannuronic acid to guluronic acid (MG) blocks accounted for the largest proportion of ALE from the two granular sludges. In particular, the extracellular polymeric substances (EPS) extracted from bacterial and algal-bacterial AGS contained about 25.10 ± 1.85 and 19.53 ± 0.04 mg-P/g-SS, respectively, and both granular sludges possessed high P bioavailability of 97–99%.