Effects of flocculation conditions on agglomerate structure

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Abstract

Direct experimental measurements of individual floc size and settling velocity allow the agglomerate density or porosity to be determined. Results indicate that density generally decreases with increasing floc size. The experimental data were fitted to an empirical model which was used in statistical testing for significant differences between measured floc density-size relationships in different systems. The effects of flocculation system variables such as agitation intensity, polymer concentration, mixing time, solids concentration, and primary particle size on resultant floc structures are presented and discussed. Based on these results, a simple multistage model is postulated.

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