Screening Of Efficient Flocculant Producing Bacteria And Their Flocs’ Characteristics

Bioflocculants (abbreviated as BF) is a new, efficient, inexpensive water treatment chemicals which produced by biotechnology, including microbial fermentation, extraction, refining. Compared with inorganic flocculants and synthesis of organic polymeric flocculants, has a more unique, superior performance, its scope of application covered the livestock industry, construction, printing and dyeing, tanning industry, municipal wastewater, food and hospital waste water treatment, wastewater from fermentation industries and the food industry and other fields, with broad commercial prospects. But domestic bioflocculant research started relatively late, flocculation mechanism of rare. This subject is mainly screened high efficient flocculant producing strain and study on characteristics of different strains producing flocculants and flocculant of Floc during flocculation.From environmental samples were screened8high efficiency flocculant-producing microbial communities, through the microbial community study found that high microbial flocculation rate with good carbon source utilization of capacity, and had rich biological diversity. Then9different high flocculation efficiency bacteria were screened from the8microbial communities, through identification of surface morphology, Physiology and Biochemistry and molecular biology identification identify9types of strains of bacteria.Bioflocculants produced by9flocculating bacteria are mainly extracellular secretion of the substance, the bioflocculants by FTIR analysis, the result showed that the structure was contains many sugar and protein absorption peaks of the typical groups, including O-H, N-H, C-H, C=O in the-NHCOR-, C=O in-COO-,etc. Physiological and biochemical analysis also indicates that the main flocculant for glycoprotein, good thermal stability. Through the SEM analysis the9kinds of flocculant has different shapes. Flocculation mechanism research shows that at flocculation process, Zeta potential value upwards, flocculation mainly for electrical and and compression electric double layer effect, because flocculant contains multiple adsorption site, through the adsorption effect so as to form the large bridge flocculant body. The laser particle size analysis form a body of flocculant for most particles between10um to50um, flocculation droplets than to loose, but settlement has a better performance; SE3flocculant of droplets can achieve maximum616.68um, droplets flocculent tight settlement good performance. Flocculent body fractal research shows that2D fractal dimension, the greater the effect the smaller the porosity of the body, the body was tight.