Plate Settler Spacing

Fall 2008 Minutes

11/28/08

Accomplishments

• Formation of a stable floc blanket
• Control of floc blanket level
• Effluent turbidity has been as low as below 1 NTU with a stable floc blanket!
• We have a few days of good data for the 9mm spacing

Metrics

• Data

Outcomes

• We decided to use one flocculator instead of two to prevent the breaking of flocs
• The flocculator was extend to increase the number and size of flocs forming
• Floc blanket formation requires a completely drained system
• The floc blanket should be below the settling tubes for optimumm effluent turbidity (this may be because the water is being pulled off the top)

Issues

• The system has been flooding due to a build-up of air bubbles
• We are having process controller turn off the system when the water level in the raw water bucket is too high
• There is still a lot of difficulties with getting air out of the system when first starting up. This may be due to the draining method, which drains from the flocculator at the same rate that it drains from the settling tube.
• The draining/filling method makes the system a bit difficult to run by yourself, we need to work on eliminating these operational challenges.