This paper presents a numerical study on the flocculation and sedimentation process of fine cohe-sive sediment particles based on the Smoluchowski equation and its extended model. The simulated mini-mum size of sediment particles is 5.0μm,the floc fractal dimension is 1.78,and the height and diameterof the simulated sedimentation measuring cylinder are 1.75 m and 0.14 m,respectively. The simulated sedi-mentation time is 300 min. Initial conditions for this simulation include a uniform distribution of sedime...