Abstract
The shapes, sizes and settling velocities of flocs of kaolinite particles coagulated in 0.1 M NaCl solution at pH 10 were measured and the porosity of the flocs was calculated using the obtained data and Stokes' law. The results were as follows:
(1) Although the diameters of the flocs ranged from 30 μm to 180 μm, their shapes were almost all spherical.
(2) The porosity of the flocs was in the range of 97% to 99%.
(3) The face to face coagulation model can not explain the results of (1) and (2). Only the point to point coagulation model proposed by the authors can reasonably account for the results.
