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The flow rate (Q) through the tube settlers is calculated based on a desired upflow velocity (Vup) of 100 m/day through the tube settlers. We note here that the tube settlers are angled at the standard sixty-degrees from the horizon in order to reduce plate length. We also note that flow through the tubes is assumed to be laminar, resulting in a parabolic velocity profile with the maximum velocity (Va) occurring at the center of the tubes. The desired upflow velocity is dependent primarily on the critical velocity (Vc) necessary to allow flocs to settle out of the water:
Below is the calculation of are the equations used to calculate the flow rate, regulated by a pump, through the tube settlers.:
Where Ased is the cross-sectional area of one tube and Qsed is the flow rate through one tube settler.
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