Abstract
A systematic observation of the sedimentation behavior of montmorillonite suspension coagulated in 1.00 M NaCl solution was made using glass cylinders of different heights in the semi-dilute regime which starts from a very slow rate followed by gel collapse ending slow consolidation. Intensive analysis was done for the maximum interface settling rate (Q) as a function of the volume fraction of montmorillonite (φ ) using cylinders of different heights. The velocities were plotted against the reciprocal height of the cylinder to obtain the velocity of infinite height as a function of the volume fraction of montmorillonite. On the basis of Richardson-Zaki’s equation; Q=Qf(1−αφ )4.65, the swelling ratio of α, and the velocity of zero limit dilution (Qf) were obtained from the slope of the plot and the intercept of the abscissa, respectively. Using the obtained values of αand Qf, the representative diameter of the floc, df, is determined by the application of Stokes’ Law. The obtained values of Qf and df were confirmed to be consistent with the result of the measurement of the settling velocity of a single floc against diameter independently determined by the method of Two-way camera.
https://ror.org/02956yf07 
