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.

February 4, 2008

Entire Group met to drain and clean out the tank. All sand and dirt was removed.

February 5, 2008

Sara- in San Francisco for ESW conference.
The rest of the group met to cut the larger port holes. The holes were extended upwards because we wanted to maintain the width to prevent short-circuiting. The final design was 85 cm high by 5.5 cm wide. This was a conservative design because the holes are not cut perfectly straight due to the difficulty of cutting in the tank.  The sides of the inner tank were re-caulked after the cuts were made.

February 11, 2008

Plant up and running. Up welling noticed coming around the bottom panel. This was causing the first and third sections to fill at the same rate.
Plan to correct upwelling problem - caulk the bottom of the tank. Tank was left running to have comparative data do evaluate the affect of the bypass on the floc formation and plant performance. Turbidimeters cleaned and dessicants returned to lab to be dried out. Edited goals and added details and created milestone dates.

February 12, 2008

Rebecca takes new tube settlers to the plant. (2 broken last time) measures the flow rate coming out of the new tube settler pump and sets the flow rate to 40 ml/min. Takes dessicants back to the plant. (monitor broken)

February 14, 2008

Sara, Kevin, David meet with Raul to discuss the sedimentation tank plan, and what help he needs. Raul is working on the design over the weekend and design review will shortly follow in the next week.
The tank was drained again to prepare and dry the tank for caulking. Given the amount of time needed for the tank to dry for caulking (about a week) it was decided to add additional sand to the cracks around the bottom panel in the third section and in the first section but just in the very first section by the inlet. It was hoped that enough headloss could be created to decrease the severity of the by pass. Upon observation it seemed to at least help the issue a little bit. On Monday if the by pass still seems to be an issue the tank will be drained and caulked before further tests are run.

February 15, 16, 17, 2008

Sara - updating old papers up to the wiki. Work done on Teach-in Presentation. David- Finished draft of gannt chart

February 18, 2008

Entire group met at plant along with Leah to review plant data from the weekend and discuss options for the Automated flow device. Also reviewed options for insulation and lighting on McMaster, and came up with potential options. Sara also described testing procedure to the rest of the group and Rebecca cleaned the turbiditymeters. Plant results were inconsistent, and the turbidity in the flocculator continues to be larger then the inflow water. Heavy condensation was noticed on the tubes connecting the tube settlers to the turbiditymeters, indicating a significant temperature difference between the water and the air. Pictures were taken of various components of the plant, and have been put on the Wiki.
Kevin brought a clear pipe and placed it down the side of the tank where upwelling is suspected to be a problem. Adjusting the pipe, the water in the pipe would rise up to two centimeters above the tank water level. Based on Bernoulli equations this shows that there is a significant velocity, and thus quantity of water bypassing flocculation. We concluded that this does not effect the turbiditimeters because they are placed upstream of the upwelling (the non-flocculated water is not going into the turbiditimeters), however upwelling does effect the flow rate. We must determine if this is significant.

February 21, 2008

Sara, Dave, Leah and Rebecca met at the plant today. The upwelling that Kevin measured previously was remeasured to confirm the significance of the bypass around the bottom panel. Today the height difference in the tube versus in the tank was 3/4". This was still considered significant enough that it was decided that the bottom of the tank would have to be caulked. The tank was was shut off drained and cleaned out to prepare for the caulking. A clear glass 400mL beaker and a large plastic 1000mL beaker were brought to the plant to test the sampling methods that will be used for the alternative method. The glass beaker was determined to be better. Rebecca calculated the time that the beaker sample would have to settle to be equivalent to the settling tubes. It was determined that instead of insulating the tube settlers to prevent the temperature change from affecting settling the tubes were submerged. The apparatus to keep the tubes submerged and at 60 degrees was also determined. They will be suspended off of a tube resting across the dividers. Strings will run down from the resting cross bar to the glass settling tube to hold it in place. To keep air in solution and keep it from bubbling out in the turbiditmeters and skewing data, the outlet from the turbidity meters is going to be raised to increase the pressure in the system and keep the air in solution. Dave is figuring out the necessary height to create enough pressure to keep the air in solution. Leah will also be implementing her entrance tank this upcoming week while the tank is off for caulking. Tom will be adding in the digital flow meter on Friday.

February 25, 2008

Sara, Dave and Kevin met at the plant to check on the status of the flow meter and make sure that the tank was dry prior to calking on Friday. The pressure head and entrance tank setup was discussed. The turbidity tube set up was adjusted to allow for the pressure head device and we set up the schedule for the week and decided on a format for posting the individual gannt charts on the wiki.

 February 28,2008

Sara, Dave, Leah and Rebecca met at them plant today. We installed the pressure head device and reconfigured the turbiditymeter tube set up. We made the pressure head device as tall as the room would allow, with the idea that we will re-fit it to the correct height once we have records of the temperature difference between the inflow water and the turbiditymeter vial. We discussed possible methods for suspending the tube settlers. We also reffited the inflow pump to allow for Leah's auto alum control device, which we will install once we get the parts on Monday. We also reviewed possible actions to take once the plant is running and made a rough outline for next week.  

February 29,2008

Sara and Kevin met at the plant today. Kevin calked the bottom panel of the tank to prevent upwelling during operation. Caulking the bottom adequately is very important because if it does not seal properly, then more time will be necessary to fix the problem. The walls were wiped down to make sure dirt or particles wouldn't effect the cohesion to the wall. Also, the edges were vacuumed to get dirt and water left over under the crack. This could also effect cohesion. Kevin also helped Tom cut the in-flow pipe in order to put in the flow meter. The flow meter was not fully installed because Tom had other stuff to do.  Sara refitted the baffle connections in section 2 since we noticed that many of the connections were loose or broken.

February 30,2008

Dave went to the plant today to refit the baffle connections in section 1.

March 3, 2008

Kevin and Dave went to the plant to try to get the plant running. However, the in-flow pipe had not been put back together (the flow-meter was supposed to be installed), as Tom had promised. Instead we figured out a way to support the in-flow bucket using metal braces. We decided on a design with Tom, and are going back tomorrow to work on it. 

March 4, 2008

Sara, Kevin and Dave went down to the plant to work on the tank modifications. Kevin and Tom worked on installing the flow-meter, while Sara and Dave prepared the support set up for the flow control device. The bracing system is almost done, but we now need to make some modifications to the flow control bucket to make sure spilling does not occur. The flow-meter will require more work, but significant progress was made on it today.   

March 6, 2008

Rebecca developed a data analysis method, working with mathCAD programs used in previous semesters by Carol Serna.

March 8, 2008
Sara, Dave and Kevin meet to work on the Sedimentation tank design. Ran existing programs and also created new program to back calculate design for the existing tank size. Emailed Chris to learn more about optimum sludge blanket thickness, relationship of the sludge blanket and the lamella.

March 9, 2008
Kevin went the plant to add sand, replace baffles and finish stand for flow meter bucket.

March 8, 2008
Sara, Dave, and Kevin began work on the sed tank design. We used existing files and tried to think up how the sed tank would function schematically. We concluded that the tank will require a plant leveling tank to set the water level in the sed tank and to divert the desired amount of water to the sed tank.

March 10, 2008
Sara glued rapid mix tube in place. Ordered ratchet straps to secure the flow meter bucket and the thin riser pipe that is increasing the pressure on the turbidity meter set-up. Found ring stand see clamps in the lab to use for securing the in tank light.

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 

Sara, 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.

April 7, 2008

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 construct all connections and manifolds in the sludge blanket design.
 

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 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.

April 15, 2008

Gemma and Ian come to the plant to give some pointers to Rebecca and Nara about process controller. 

 April 17, 2008

Nara and Rebecca go to the plant to work with the process controller.  They install the new version of the process controller and LabView, but find that the method files don't open in the new program.  They request remote access to the computer so that the programs can be worked on more easily from campus.  They try an old PCM that seemed to be collecting data well in July.

 April 20, 2008

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 21, 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 meeting