Screening of Bioflocculant-Producing Strains and Study on the Production and Oily Wastewater Flocculation Characteristics

A flocculant-producing bacterial strain, named KL3-5 was screened by means of the pyridine screening from 10 soil samples. The flocculating rate of bioflocculant produced by KL3-5 strain was 94.6%. The strain KL3-5 was identified as proteusbacillus vulgaris of Enterobacter family according to its morphological, physiological, biochemical, and 16S rDNA sequence characteristics. It was indicated that all of the content of bioflocculant was polysaccharides by the qualitative analysis of sugar and protein. When flocculant addition was 0.05mL, the removal rate of COD and oil could get to 32% and 67%, and the removal efficiencies were better than the PAC which was 61% and 30%, respectively. The flocculation sediment from KL3-5 was only 0.6g·L^-1.