Rome-Ming Wu This email address is being protected from spambots. You need JavaScript enabled to view it.1, Kuo-Jen Li1 and Shang-Suan Sung2

1Department of Chemical and Materials Engineering, Tamkang University, Tamsui, Taiwan 251, R.O.C.
2Chemical Engineering Department, National Taiwan University, Taipei, Taiwan 106, R.O.C.


 

Received: September 29, 2006
Accepted: November 6, 2006
Publication Date: December 1, 2007

Download Citation: ||https://doi.org/10.6180/jase.2007.10.4.05  


ABSTRACT


The most commonly used experimental techniques to monitor the aggregation kinetics and to characterize structures of aggregates are scattering of light, X-rays and neutrons. We investigated in this study the coagulation dynamics for the humic acid-kaolin-polyaluminium chloride (PACl) aggregates using small-angle light scattering techniques. The mean aggregates sizes without addition of humic acids were only mildly affected by the kaolin concentration. With the addition of humic acids, the floc sizes are slightly reduced. At 600 rpm, the average aggregates size was larger with lower fractal dimension, i.e., the aggregates were large and loose; at 800 rpm, the average size was smaller with higher fractal dimension, i.e., under high shear rates, the aggregates were small and compact.


Keywords: Dynamics, Flocculation, Fractal Dimension, Small-Angle Light Scattering, Size


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