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Experiment 2- Ramp State with 15.3 mm tube
Experiment 2: Ramp State Function with 15.3mm Tube Settler Diameter
This experiment starts with a flow rate of 6 mL/min and gradually increases to a flow rate of 140 mL/min over the course of 24 hours. This flow rate range corresponds to a capture velocity range of approximately 11 m/day to 256 m/day.
Figure 1: Effluent Turbidity vs. Flow Rate
Conclusions
Unlike the results for the 9.5mm tube, there isn't a sharp increase in the turbidity which would clearly indicate the critical velocity. Rather, there is a gradual increase in the turbidity, showing that floc roll up is happening, however it is not possible to identify the exact critical velocity from this range of capture velocities tested. Like the 9.5mm tube, the turbidity eventually reaches a plateau, indicating the point at which the maximum amount of flocs are rolling up the tube. The discrepency between the results of the 15.3 mm tube and the 9.5 mm tube is currently being investigated.