Experiment 1

[MikeZarecor]

We suspect that the cause of decreasing performance in our experiments is the accumulation of coagulant on the tubing. To test this we are going to increase our coagulant dose significantly from 1.4 mg/L.

Note: High G Floc is testing hydrophobic tubing, this may be a better solution

[MikeZarecor]

It looks like pro coda is not controlling our clay pump quite right, lets revert to the old method file from earlier last semester and see if that works properly. If not we can compare our method file with the high g floc team.

[MikeZarecor]

The data we got from a first run of this experiment did not turn out very well. Lets meet next Tuesday and try to troubleshoot that.

[MikeZarecor]

I suspect that there is a problem with our coagulant pump, math cad predicted our 5L should last for 16 hours, but after 24 hours only 2 or 3 L was used. Lets double check the flow rate from our coagulant pump Tuesday.

[SnehaSharma3257]

Today we completed an experiment to ensure that the coagulant pump is working correctly. We re-calculated the flow rate and dosed accordingly. We used 1.4 mg/mL of coagulant and 20 RPM speed for the pump. One interesting observation we made was that the influent turbidimeter NTU readings shoot up as soon as the coagulant begins running through the system. We consulted with Monroe and he suggested that this may be due to the change in pressure experienced by the system.

[MikeZarecor]

This is the data from Experiment 1A. This test was conducted on 2-27 at 3 mm/s upflow velocity and 1.4 mg/L coagulant dose.

Experiment 1A 2-27.xls.xlsx

[MikeZarecor]

This is the data from Experiment 1B. This test was conducted on 3-1 at 3 mm/s upflow velocity and 2.8 mg/L coagulant dose.

Experiment 1B 3-1.xls.xlsx

[MikeZarecor]

On 3-1 High Rate Sedimentation met with our RA, Tanvi. We discussed how the semester has been progressing. We decided that cleaning the turbidimeters mid way through experiments was not beneficial. We also discussed moving the MathCAD files over to atom/hydrogen. This will be done as part of our manual. She is experianced with both languages, so if we have questions we can contact her.

[JC-Conneely]

We conducted experiment 1c on 3/6/18. For this experiment, we used a coagulant dosage of 4.2 mg/L and an upflow velocity of 3mm/s.

[MikeZarecor]

We discovered that procoda was not properly logging our effluent turbidity. This invalidates experiment C. We will repeat this experiment on 3-8

[SnehaSharma3257]

We conducted Experiment 1D on 3/7/2018. The test was conducted at an upflow velocity of 3 mm/s and a 5.6 mg/L coagulant dose.

[MikeZarecor]

This is the data from Experiment 1D. This test was conducted on 3-7 at 3 mm/s upflow velocity and 5.6 mg/L coagul Experiment 1D.xlsx ant dose.

[JC-Conneely]

Here is the data from our repeat of Experiment 1C. This test was conducted on 3-8 at 3 mm/s upflow velocity with 4.2 mg/L coagulant dose.

Experiment 1C Repeat.xlsx

[SnehaSharma3257]

We conducted Experiment 1E on 3/13/2018. The test was conducted at an upflow velocity of 3 mm/s and 7.0 mg/L coagulant dose. Unfortunately, Windows updated while the experiment was running and the collected data was lost. Experiment 1E was conducted again on 3/15/2018 at an upflow velocity of 3 mm/s and 7.0 mg/L coagulant dose.

[SnehaSharma3257]

An interesting observation: a gel-like precipitate had formed at the bottom of the sedimentation tank after completing the first attempt of Experiment 1E.

[JC-Conneely]

It would be nice if we could do something about windows installing updates/shutting down during experiments. @monroews

[JC-Conneely]

We conducted experiment 1e on 3/16/18. For this experiment, we used a coagulant dosage of 7.0 mg/L and an upflow velocity of 3mm/s. Experiment 1E.xlsx

[SnehaSharma3257]

We realized that the dosing valve was left closed for experiment 1E conducted on 3/16/2018. Thus, we re-did the experiment on 3/20/2018, making sure to open the dosing valve and turn on the coagulant pump. Experiment 1E Repeat on 3-20.xlsx

[caching13]

@MikeZarecor @JustinConneely @SnehaSharma3257 To prevent Windows updating/shutting down during experiments, try restarting the computer after you finish/before you run an experiment. Usually that will keep Windows happy for just long enough. If that doesn't work, try playing with the settings (google has some suggestions).

[SnehaSharma3257]

Experiment 1F was conducted on 3/22/2018 at 8.4 mg/L coagulant dose and an upflow velocity of 3 mm/s.

[JC-Conneely]

Attached to this comment is the data for experiment 1F. The effluent turbidity data for the first few minutes is markedly higher than normal due to delayed coagulant addition. Once the floc blanket formed, however, the effluent stabilized.

Upon ending the experiment, it was observed that there was a dense layer of flocs/gel on the bottom eight inches of the recirculator, which did not occur at lower coagulant doses. Pictures of this phenomenon are attached to this comment as well.

Experiment 1F.xlsx