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According to the predictive flocculation model proposed by Swetland et. al., 2012, large flocs do not significantly contribute to turbidity removal -- only small colloids can collide effectively and aggregate to a size that will be removed by sedimentation. Based on the hypothesis that "large flocs are useless", a floc breakup procedure was devised. Results obtained using a coiled tube flocculator and flocculation residual turbidity analyzer (FReTA) shows that higher turbidity removal was achieved after breaking the flocs, comparing to results using the same method but without floc breakup. Therefore breaking flocs at regular intervals to maintain continuous growth will promote better performance of flocculation. This research finding provided a good reference for future hydraulic flocculator design.

Hypotheses

Wiki Markup1. Only laminar flow occurs in tube flocculators.  2. Colloids cannot attach to large flocs at maximum size thus we need to break those flocs to maintain continuous growth. 3. At low coagulant doses, the residual turbidity is relatively high because the attachment efficiency is not big enough to allow flocs to form. With the increase of coagulant dose, attachment efficiency rises so the residual turbidity is lowered.  4. Discrete settling is assumed in analysis of data since the distance Z is much less than the 0.5m interval between sampling ports used in conventional flocculant settling tests. \[citation-5\] 5. Flocs will collide and grow when they travel from one breakup position to another. 1. Only laminar flow occurs in tube flocculators. flocculators. 
2. Colloids cannot attach to large flocs at maximum size thus we need to break those flocs to maintain continuous growth.
3. At low coagulant doses, the residual turbidity is relatively high because the attachment efficiency is not big enough to allow flocs to form. With the increase of coagulant dose, attachment efficiency rises so the residual turbidity is lowered. 
4. Discrete settling is assumed in analysis of data since the distance Z is much less than the 0.5m interval between sampling ports used in conventional flocculant settling tests.
5. Flocs will collide and grow when they travel from one breakup position to another.

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