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This design featured a flocculator with a horizontal length of 48cm48 cm. It was determined that this length was too long. It unnecessarily increased the residence time , theta, of the plant. This resulted in an increased degree of mixing, so that the shear at the end of the flocculator was too high, and caused large flocs to break up prior to entering the sedimentation tank. This length was originally chosen to ensure enough shear to form flocs, but was overestimated, since the maximum floc size was observed at approximately 28cm 28 cm into the flocculator. Thus, the length after reaching the maximum floc size became detrimental to maintaining these flocs.
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