Experiment 1: Average Effluent Turbidity vs

Velocity - Low Floc Blanket Formation

During Experiment 1, the following velocities were used: 5 m/day, 10 m/day, 15 m/day and 20 m/day. This experiment was set on low floc blanket formation.

Figure 1: Log(Effluent Turbidity) vs. Time

Conclusions

As expected, the effluent turbidity is much higher than that of the control experiment. The presence of saturated water in the influent has a very clear negative effect on the effluent turbidity. The bubbles released as a result of a pressure drop in the system disturbed floc formation, allowing less floc particles to settle and more, smaller, lighter particles to leave with the effluent. The occasional spikes in the data represent an air bubble floating up through the settler which creates a temporary spike in the turbidity.

Experiment 2: Effluent Turbidity v Time - High Floc Blanket Formation

During Experiment 2, the following velocities were used: 5 m/day, 10 m/day, 15 m/day and 20 m/day. This experiment was set on high floc blanket formation.

Figure 1: Log(Effluent Turbidity) vs. Time

Conclusion

Like the data collected for the floc blanket on low, the effluent turbidity for the floc blanket on high is higher than the effluent turbidity of the control experiment. The difference isn't as great as that found in the experiment with the low floc blanket formation due to the intitially low effluent turbidity for this particular experiment. High floc blanket formation already results in an increase in effluent turbidity. The spikes in the turbidity represent an air bubble floating through the plate settler creating a temporary elevated turbidity