| Abstract:A real-time methodology has been developed to study the flocculation behavior of kaolin suspensions induced by cationic polymer, by using the focused beam reflectance measurement (FBRM) system. The turbidity, laser diffraction particle size analyzer and light microscopy were used to characterize the properties and morphology of the flocs. The fractal dimension was investigated during the flocculation process based on the fractal theory. Furthermore, the results were analyzed using a model of the flocculation kinetics, based on the Smoluchowski model. Detailed investigations showed that the morphology (size and structure) of the flocs, the turbidity of the supernatant, and the flocculation rates of particle numbers were highly dependent on the CPAM dosage. Records and analysis of FBRM indicated that the mean chord length of the particles increased with CPAM dosage, which was corroborated by laser diffraction particle size analyzer and turbidity decreased. As the extension of time, the floc structure changed during the flocculation process whilst fractal dimension increased, forming relatively tighter and compact structures. The different floc morphology under different CPAM dosages was shown more obviously by the photomicrography. During flocculation, the higher the flocculation rate of particle numbers, the better the flocculation efficiency will be, but it still need more time to reach the equilibrium state. |
