Screening and Characteristics of Microbial Flocculant

This paper focusesd on a flocculants-producing bacteria isolated from active sludge samples taken from Municipal wastewater treatment plant.The flocculation was significantly improved by the optimization of culture conditions.Three extraction methods were compared to reduce the cost of the production of microbial flocculants.The highest level of flocculating substance accumulation(1.33 g/L) was attained after 66 hours of cultivation at 30 ℃ and 160 r/min with the initial medium of pH 7.5 and CTAB extraction process.The 71.8% flocculating activity was obtained without the presence of CaCl2.