Pilot Plant Sedimentation Tank Meeting Minutes
Fall 2008 Minutes
November 21, 2008
Accomplishments
* Began a beginner's guide to the Pilot Plant on the wiki. Have made pages for a glossary and an FAQ page. Also linked to the Maintenance and Troubleshooting page.
* Attempted experiment 1, testing turbidity with lamella at different heights of a sludge blanket. (See issues for why attempt was not entirely successful and solutions.)
* Temporary Fixes (placed under Maintenance and Troubleshooting):
- Determining the height of the floc blanket
- Draining the sed tank with lamella
Outcomes
* Tom fixed the pump whose motor hasn't been turning. Apparently there was also a problem with the fuse.
Metrics
* Tried to lower sludge in lamella tank to collect data at different heights. Drained tank every 5-10 minutes for 3 hours, for as long as very dirty water came out as time. Sludge blanket did not budge. Took data for both tanks anyway. Measured average turbidity about between 4.8 and 5.5 for all sets of measurements. For lamella tank, took data before trying to lower tanks, and after skimming flocs and dirt off top and trying to lower.
* Noticed that turbidity in non-lamella tank lowered after being left undisturbed. Average after some settling was just under 5.0.
* Skimmed flocs and dirt off the top of the free surface in the lamella tank, after which the turbidity in the tank began to decrease. Since the turbidity was dropping when Shaina left the plant, she set up the data log to record the turbidity every 10 minutes until someone else visits the plant.
Issues
* As of Friday: Still no sludge blanket in the non-lamella tank. Will have to construct a down-turned opening to attach to the inflow opening so that flocs can be sucked up.
* Sed tank with lamella is difficult and unnecessarily messy to clean. Have temporary fix, but worked with Tom to design a permanent fixture.
* Sludge blanket in tank with lamella could not be lowered in spite of a substantial effort to do so.