Effect on composition and quantity of extracellular polymeric substances in an innovative hybrid membrane bioreactor under different sludge retention times

ABSTRACT

This study investigated the influence of sludge retention time (SRT) in three hybrid membrane bioreactors to treat domestic wastewater at different SRTs (10, 20, and 40 d) simultaneously, based on extracellular polymeric substances (EPS) analysis. The results showed that significant positive correlation existed between SRT and humic acids quantity in TB-EPS, humic acids quantity in S-EPS, DNA quantity in S-EPS, and total quantity in TB-EPS, with the correlation coefficient 0.9992, 0.9980, 0.9973, 0.9821, respectively. Significant negative correlation existed in SRT and proteins in TB-EPS, proteins quantity in S-EPS, and polysaccharose in S-EPS, with the correlation coefficient 0.9993, 0.9107, 0.8552, respectively. A high logarithmic relationship existed between supernatant turbidity and SVI. The optimal SRT was 20 d and the corresponding operational cycle of the membrane module was 109 d.

KEYWORDS:

• Sludge retention time
• hybrid membrane bioreactors
• real wastewater
• extracellular polymeric substances

Acknowledgments

This work was supported by the Jiangsu Ministry of Housing and Urban and Rural Construction Project (No. 00730091), the Jiangsu Natural Science Foundation (No. BK20151161), major projects of Natural Science Research in Jiangsu higher education institutions (No. 17KJA610004), Qinglan Project in Jiangsu Province, A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), Scientific Research Projects of Xuzhou Institute of Engineering (No.XKY2013106, XKY2018245) and Xuzhou Science and Technology Project (No. KC16SQ192).

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Jiangsu Ministry of Housing and Urban and Rural Construction Project [No. 00730091];Xuzhou Science and Technology Project [No. KC16SQ192];Natural Science Foundation of Jiangsu Province [No. BK20151161];A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions [PAPD];Natural Science Research in Jiangsu higher education institutions [No. 17KJA610004];Qinglan Project in Jiangsu Province [QL20161373];Scientific Research Projects of Xuzhou Institute of Engineering [XKY2013106, XKY2018245].