[Effects of Mn2+, Mo6+ and Zn2+ on the components change of extracellular polymeric substances in activated sludge].

By specific oxygen uptake rate, (SOUR) measurements of activated sludge with different metal ion concentration, the optimal stimulation concentrations of Mn2+, Mo6+ and Zn2+ were determined. Then within each metal ion stimulation concentration range, extracellular polymeric substances (EPS) were extracted from activated sludge and its components (protein, polysaccharide and nucleic acid) contents changes were investigated. The results showed that the optimal stimulation concentration of each metal ion is 1mg x L(-1). EPS components of activated sludge vary obviously with Mn2+ and Zn2+ concentration change but not with Mo6+. After storage at low temperature, EPS quantities in activated sludge are reduced with polysaccharide reduction is the most.