Ultra-flocculation of diluted fine disperse suspensions

This article studies the impact of the hydrodynamic treatment of varying intensity on the process of flocculation and the subsequent sedimentation separation of diluted (< 1 g/l solids) fine-disperse (< 1 micron) suspensions. Using the reference water suspensions of alumina hydroxide, Na- montmorillonite, and nickel ferrocyanide, we have demonstrated that the application of the vigorous hydrodynamic treatment, characterized by the medium gradient velocity G = 2000 - 4000 s(-1), followed by a later mild hydrodynamic treatment of stepwise decreasing intensity ( G of 1000 to 30 s(-1)) can significantly improve the results in terms of flocculation and subsequent sedimentation separation of suspensions, specifically by: increasing the rate of the sedimentation of flocculated suspensions by more than two times; decreasing the residual concentration of solids in water by 4 - 10 times; decreasing the consumption of flocculants by 2 - 3 times; and enhancing the densification of the solid phase residue by 1.5 - 2 times.