Pilot Plant Vertical Flow Hydraulic Flocculation Team Spring 2008 Meeting Minutes
Jan 31, 2008
Entire group met at plant for training session and to create goals for the semester. Removed baffles for new port holes to be cut Monday.
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March 13, 2008
Sara, Dave, and Kevin continued work on the design of the sed tank. We wrote most of the programs necessary to solve for unknowns, and drew up a 2-D sketch of the plant. We also wrote and posted our midterm report of what we have accomplished on the pilot plant and the sed tank design.
Week of March 24, 2008
Preliminary design of the plate settler sedimentaiton tank was comepleted. Sludge Blanket design was edited, annotated and cleaned up to be more self explanatory. Designs were edited to accomodate the new tank sizes.
March 26, 2008
Sara, Dave, and Kevin made corrections and touch-ups to the sed tank design. Sara and Kevin met with Monroe, and decided to look into buying a new tank with more appropriate dimensions. From US Plastics we found these tanks with the appropriate cross-sectional area (.5m):
Rectangular Tank with Cover: 30"x30"x30", 115 gallons, $604, item # 8356
Heavy Duty Graduated Polyethylene Tank: 30"x36", 100 gallons, $235, Item #4210
Heavy Duty Polyethylene Tank: 36"x24"x24",90 gallons $230, item #6330
Nara, Leah, and Rebecca went to the plant. Leah investigated why the water height was high in the flow measuring bucket. She discovered that small fish and crustacea were getting into the system and getting plugging the holes. A metal grate was added to the inlet side of the pump from the stream water to filter out large particles and remedy this problem. Nara and Rebecca collected data from runs before and after the improvements to the tank set-up. They also developed a preliminary procedure for "profile runs" in which the tube settlers are moved to various locations within a relatively short period of time in order to develop a floc profile at that time. Rebecca secured the use of the CUWTP laboratory turbidimeter for grab sample testing.
Week of March 31,2008
SaraSara, Dave and Kevin completed the Plate settler tank design and refined the Sludge blanket design to make the two designs compatible. The sedimentation tanks were ordered.
April 2, 2008
Rebecca found that turbidimeter pump is in handling the added head that it has to reach without a problem. She changed the alum constants in order to get flocs to form. A = 10, B = 15. She performed some grab samples and found that the turbidity using the grab sample method was about 52% higher than the turbidity readings of the turbidimeters.
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Sara, Kevin and Dave went to the plant with the sludge blanket tank to design the layout of the two tanks as well as the location of both inlet pipes and the tank leveling tank. Tank was brought back to the lab to drill the hole for the 4in inlet bulk head fitting.
April 10, 2008
Sara, Kevin and Dave met in the lab to finalize the plate settler design and order the parts needed to build construct all connections and manifolds in the sludge blanket tankdesign.
Nara and Rebecca did a jar test on incoming plant water. The turbidity of the incoming water was found to be much lower than turbidities within the flocculator. To investigate this, they first switched the incoming turbidimeter with the second turbidimeter to see if readings were comparable. Readings were the same, so the turbidimeters appeared to be working. They also cleaned out the tube settlers to see if floc accumulation in the tube settlers caused flocs to enter the turbidimeters. This also showed no effect- turbidites were still very high within the flocculation tank. They are now considering other ways (besides the turbidimeters) to measure floc performance.
April 14, 2008
Sara Dave and Kevin begin construction of sediemtation tank. Drilling the bulkhead fitting holes drilling manifold holes. The water inlet elbow was constructed and installed.
Rebecca goes to the plant to investigate a Rebecca goes to the plant to investigate a report that the plant is not running (process controller was off). She drains and cleans the tank with the help of Mark, a plant operator. Then she restarts process controller with its previous settings.
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Rebecca goes to the plant. She collects the data from the July PCM, but finds that the increment alum function wasn't running correctly: it incremented "alum increment" but not the actual alum dose.
April 22April 21, 2008
Rebecca and Nara work with the PCs to try to improve the algorithms.
April 23, 2008
Monroe comes to the plant in the morning and helps Rebecca set up the process controller to increment alum dose.
April 24, 2008
Nara and Rebecca set up the plant to increment alum.
April 27, 2008
Sed tank design group (Sara, Kevin and Dave) meet with Monroe to work out the final kinks in the design of the plant leveling tank. Then the group reviewed the final design and made all necessary changes to adjust the head levels into the plant leveling tank. There was concern about air getting into the pipe connecting the plant leveling tank and effluent manifold. This included redesigning then secondary outlet in the floc tank.
April 22, 2008
Rebecca and Nara work with the PCs to try to improve the algorithms.
April 23, 2008
Monroe comes to the plant in the morning and helps Rebecca set up the process controller to increment alum dose.
Sed tank desing team completes tank construction, including adjustments necessitated from the design change, and outlet connections. This includes contruction of the plant leveling tank and sludge hopper construction. Sludge drain outlet, hopper outlet and the main outlet from the plant leveling tank were constructed to deposit water into the same outlet hole as is used by the flocculator. Plant leveling tank was leaking and had to be caulked this prevented us from turning the tank on today.
April 24, 2008
Nara and Rebecca set up the plant to increment alum.
Sara and Kevin go to the plant and finish set-up for plant leveling tank. The hole wad drilled in the side of the floc tank and the bulk head fitting installed. The connection from the floc tank to the sed tank was installed. A cut out was drilled in the side of the plastic sed tank to serve as an emergency outlet. If the tank over flows water will flow into the outlet channel. Water is turned on and hydraulics seem to be acting as expected.
Dave begins updating the wiki report.
April 25, 2008
Sara goes to the plant to check on the tank make sure everthing is still working correctly. Some leaks had to be fixed. The inlet pipe into the plant leveling tank had to be glued in place to avoid leaks. The 4in inlet into sed. tank was caulked to stop leaking. This was done over gluing to allow for changes and re-use of parts if necessary.
April 27, 2008
Rebecca goes to the plant in the morning to find that there is an electrical problem between the computer and the water pump. The water pump is currently plugged directly into the outlet (not being controlled by the process controller). Rebecca and Nara go to the plant to run a floc profile test. From the increment turbidity test, the optimal alum dose at this time was determined to be 30mg/L.
April 28, 2008
Dave and Kevin go to the plant the observe the working of the tank. Some flocs are noticed flowing into the manifold. They brainstorm ways to secure the hopper funnel better. (Currently string suspends it at the correct height but a more sturdy attachement needs to be designed. Ring stand or some pvc attachement were suggested. Tom offers to build a support system for the plant leveling tank to ensure it doesn't tip over or detach.
Sara worked on the wiki report, and added pictures of the sed tank.
April 29, 2008
Sara goes to observe the tank and to drill a 1/4" hole in the inlet pipe so that any trapper air can escape from then inlet pipe.
April 30, 2008
Sara continues to update the wiki.
Dave checks on the tank.
May 1, 2008
Rebecca runs an alum dose test in the afternoon. Alum dose was determined to be 10mg/L. In the evening, Nara, Leah, Kevin, and Rebecca give an AguaClara presentation at the water treatment plant, demonstrating the pilot plant to the visitors. Rebecca and Nara began another floc profile test. Test was abandoned because incoming turbidities were very low (> 2 NTU) and floc formation was difficult (incoming turbidity approximately equal to outgoing turbidity).
May 6, 2008
Rebecca runs an alum dose test, and the optimal alum dose was determined to be 25 mg/L. Average incoming turbidity was 1.4 NTU. Nara and Rebecca run a floc profile test.
May 8, 2008
Rebecca runs an alum dose test, and the optimal alum dose was again determined to be 25 mg/L. Nara and Rebecca run a floc profile test.
May 9, 2008
Nara and Rebecca work on presentation. Rebecca runs Leslie's model for Gtheta along flocculator profile. Nara creates a graphic of the testing set-up. Nara and Rebecca analyze data and update the wiki.
June 9, 2008
Summer Session begins. Group meetingRebecca goes to the plant in the morning to find that there is an electrical problem between the computer and the water pump. The water pump is currently plugged directly into the outlet (not being controlled by the process controller).