Comparison of Flocculation Properties with Use of a New Flocculation Tester

Kazuhiro Fujisaki

KIT (Kyushu Institute of Technology) Senior Academy, Japan

Abstract: A new flocculation tester was developed, by attaching a photo-coupler and switch timer to the conventional jar tester. The flocculation process was investigated by intermittently toggling the mixer switch in the ON-OFF position. During the each stop mixing period the settling velocity of the flocculated particles was measured by the light transmission method, and the concentration of solid in the supernatant was determined. Using this tester, the flocculation process was investigated by changing the flocculation conditions with specific focus on flocculation by polyaluminum chloride. The optimal dosage of flocculant was determined over a wide initial turbidity range. The results confirmed that this new tester is a very useful tool for analyzing the flocculation process.

Key words: flocculation tester, photo-coupler, flocculation process