Abstract：In biological wastewater treatment, the extracellular polymeric substances (EPS) composition affects the activated sludge stability, flocculation and biological metabolism. The EPS composition in different activated sludges (attached, suspended and hybrid) was measured at low temperatures (6℃ and 10℃) to analyze its influence on the biological adaptability and pollutant removal. A sequencing batch moving bed biofilm reactor (SBMBBR) and a sequencing batch reactor (SBR) were used in the lab scale tests. The results show that protein (PN) was the main ingredient in the sludge EPS with tightly-bound EPS (TB-EPS) having the highest proportion in the total EPS. The organic load and temperature change significantly affected the PN and PS (Polysaccharides) ratios as the mass per unit volume for different activated sludges, with the suspended sludge having lower PN/PS ratios than the biofilm sludge. At 10℃, the EPS production rate increased in the low organic load sludge, but at 6℃, the EPS contents in the attached, suspended and hybrid sludge increased with the organic load.
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2016, Vol. 56 
