The Investigation On Flocculation By Laser Light Scattering

Coagulation is one of the most crucial step in treating industrial waste water and providing high quality water for industry & drinking. Although lots studies on flocculation have been reported, based on our knowledge, the structure, size & size distribution, the weight average molecular weight of the particle of flocculation in pure water haven't been investigated yet. Accordingly, the purpose of the present paper is to perform research on these parameters using laser light scattering.Laser light scattering is a seasitive, accurate and nonivasive technique, which is surtable for the measurement of polydishersed system. In our study, the weight average molecular weight, the hydrodynamic radius & gyration radius, the size distribution and the shape of the particles of some flocculation (PACU PAC-V and PAM) in pure water were investigated using laser light scattering as functions of temperature and the concentration of the flocculation. Some removal efficiency measurements were also performed to check the relation between the physical parameters and the effect of the flocculation in coagulation. The investigations prove that, the molecular weight, the size & shape of flocculation strongly affect the removal efficacy, and do not change with the concentration of flocculation, but decrease with rising temperature.The results also show that the flocculation with high molecular weight and greater particle size have better performance and high efficacy in removing dust in water. Our research on the mechanism of flocculation shows that, the molecular weight and particle size of flocculation strongly affect cohesion and conjunction at the same time, the structure and shape affect coagulation, and molecular weight strongly affect the attraction and falling of the flocculation.The research indicates that molecular weight and particle size of flocculation are two of the most important factors in influencing the removal efficacy. Therefore,, several ways of increasing the values of molecular weight and the particle size have been suggested for improving the flocculation in the paper. We believe that, our investigating on these parameters will provide experimental evidence & theoretical bases for the research on flocculating mechanism.