Overview of Methods
Robustness of our plate design is defined as the ability of the plate settlers to produce 1 NTU water over a variety of non-ideal conditions. One set of non-ideal conditions was building a floc blanket with underdoses and overdoses of alum to measure performance through effluent turbidity from the tube settler. Other non-ideal conditions that should be investigated are organic matter in the influent, varying influent turbidities, and other changes, such as pH, in the chemistry of the water.
Plate settler spacing is an important factor in determining the height of the plant clarifiers. Theoretically, if we could find a way to maximize their performance at the lower-limit of spacing and height it would be possible to decrease height of the sedimentation tank and lower plant costs.
In these experiments the alum dosage supplied to the flocculation system was varied in order to study how properties of flocs and the floc blanket affect the effluent turbidity produced by the tube settler. The experimental set-up is identical to the one used in Spring 2009, and from our results we hoped to analyze velocity gradient thresholds and possibly investigate how changing influent water chemistry affects the setter's efficiency.
...