1. School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China; 2. Design Institute of Beijing Sound Environmental Engineering Co. Ltd, Beijing 101102, China; 3. Engineering consulting and supervision of China Railway First Survey & Design Institute Group Co. Ltd, Xi'an 710000, China; 4. Solid Waste and Chemicals Management Center. MEP, Beijing 100029, China
Abstract：In this paper,the long-term effect of C/N ratio on extracellular polymeric substance (EPS) in the sequencing batch reactor (SBR) treating synthetic wastewater was investigated under four C/N ratio conditions (0,5,10,15).The results showed that the C/N ratio had a significant impact on EPS and its composition.With the increase of C/N ratio (0→5→10→15),EPS and tightly bound EPS (TB-EPS) content increased,while,loosely bound EPS (LB-EPS) decreased slowly.TB-EPS was dominant in EPS (the percentage of TB-EPS/EPS was 77.4~93.6%).Moreover,protein (PN),Carbohydrate (PS) and DNA in EPS and TB-EPS increased with the C/N ratio increasing.PN,PS and DNA in LB-EPS decreased as the C/N ratio increased.Moreover,capillary suction times (CST) and specific resistance to filtration (SRF) increased when the C/N ratio increased,and caused deterioration in sludge dewaterability.
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