Pilot Plant Sedimentation Tank Meeting Minutes

Fall 2008 Minutes

November 28, 2008

Accomplishments

• Discussed with Monroe expectations for the PPST team for the rest of the semester.
• Kellie fabricated a cage for the pump so that leaves and other debris are not a problem in the future. We left the existing screen on, just as a secondary protection, and put the pump back.
• Solved the problem of no alum dosing on Wednesday, with Tom's help.
• Took some data for both sed tanks.

Outcomes

• Flocs are again forming.
• Discovered that the drain on the tank that hadn't been forming a sludge blanket had been left open. When I noticed this, nothing was draining out; however, sludge might have been draining out earlier, perhaps in intervals. Closed the drain.

Metrics

• To get alum pumping again, had to increase alum dosing to 100 mg/L. Gradually decreased to 50, then to 25, then to 20. Tom suggested decreasing the dose to 10 mg/L because the water temperature was close to freezing. Tested different alum dosages until settling on 15 mg/L.

Issues

• Still no sludge blanket in non-lamella tank.
• No flocs were forming as of Tuesday. This problem was solved on Wednesday.