Pilot Plant Sedimentation Tank Meeting Minutes

Fall 2008 Minutes

November 14, 2008

Accomplishments

* Kellie updated the goals page on the wiki to reflect our new goals as well as correct the format to meet the given standards.
* Met with Monroe to discuss the plan for the rest of the semester and to clear up some confusion.
* Finally operating and able to test the water in the sed tanks!
* Cleared leaves from the pump that brings water into the Pilot Plant, so now flows should be stable!
* When the flow started up again, the water started gushing out of one of the pipes that leads to the flocculator. Problem solved by adding some extra height to the pipe.
* Determined that many more flocs flow to the left sed tank than the right (the control) by stirring up the sludge at the bottom of the flocculator tank and observing the flow.
* A trivial labeling system has been made for the four tubes in the flocculator pump so that nothing is misplaced when the pump is moved to the sed tanks.

Outcomes

* Once the floc blanket develops, we will start running a siphon to control the level of the floc blanket with respect to the lamella.
* Now running the plant at 100L/day!

Metrics

* On Thursday 11/13/08 there was no floc blanket whatsoever in the control sed tank. This had a turbidity of 10.26 NTU. The tank with lamella did not have a clear floc blanket either, however its turbidity was lower, with an average of 7.72 NTU

Issues

* Kellie forgot to email Mark to tell him that she wanted to go to the plant on Saturday, so no one was at the plant to let her in. Will make sure to contact the operators if going on a weekend in the future.
* On Thursday, we had good looking flocs, and yet no floc blanket. I believe that one will form soon though, since the flocs looked as if they were suspended nicely in the water.
* Although we cleared the leaves this time, the same problem will likely occur next fall, when leaves start to fall again. The screen is also not completely covering the inlet to to pump.
* Pump B (Sed tanks to turbidimeter) is not working. Probably a problem with the motor, as the power is turning on, but nothing is moving.
* A floc blanket is not forming in the control tank, perhaps because most of the flocs are being directed to the left tank. This could be because the flow from the second channel of the flocculator is approximately parallel to the mouth of the pipe leading to the control tank, whereas flocs can flow easily into the pipe leading to the left tank.
* We have had problems with floc blanket formation all semester, perhaps partly because not enough flocs are flowing into the sed tanks. Shaina's opinion is that efficiency could be greatly improved if a removable extension were created to suck sludge from the depths of the flocculator into the pipes.