Week Six (May 8th, 2018 - May 14th, 2018)

         During this week's lab, we primarily focused on performing a series of tests in order to see how successful our design was in filtering out the different solutions in the lab. First, we performed organic solution testing, which essentially is a solution that is mixed with pink dye. And then we performed the metal solution testing which had calcium ions and was a bluish color. We continued with the design that we created and tested last week. The design was sand and the activated charcoal mixed together with a filter paper attached to the bottom of the bottle. We used this specific design for two trial runs.

Trial one is being tested

	Sand Mass	Charcoal Mass	Time	Tested
Trial 1	60.2 g	1.0 g	16:54	40 mL Organic Solution -> 30 mL clear water
Trial 2	60.2 g	1.0 g	15:28	50 mL Metal Solution -> 23 mL light blue water

         The first trial run that we tested the organic solution was filtered right out of the water. 75% of the water was filtered out by our design, while the remaining was soaked up by the sand and charcoal mixer. In the second trial run, we lightly patted down the mixture, so any remaining mixture was removed. We tested the metal solution in the same design and only 46% of the water was filtered and the remaining was trapped in the sand and activated charcoal mixture. However, with these two trials, we realized that our flow rate was extremely low. So, we were adamant about trying to improve not only the flow rate, but our design overall due to the metal solution that still appeared in the "filtered" water. 

Olivia is working on our updated design

The third trial is underway

       We came up with a solution to help increase the flow rate in our design. The main reason that our flow rate was so low was due to our usage of 2L soda bottles that we were using had such a concentrated opening that the water was being forced out at such a slow rate. We opted to change the bottle that we had been using for the past five weeks and we were able to secure a Simply Lemonade bottle. A bottle that has a larger neck and larger surface area. We also added a new component, charcoal chunks, in our sand and activated charcoal mixture. The filtered paper at the nozzle of the bottle was kept the same way. 

	Sand Mass	Act. Charcoal Mass	Reg. Charcoal Mass	Time	Tested
Trial 3	60.2 g	1.10 g	1.5 g	0.45	50 mL Org. Sol. -> 37mL clear water
Trial 4	90.9 g	0.9 g	15.7	2:23	50 mL Metal Sol. -> 62 mL faint pink and blue

       Now that we used a completely different bottle, in the third trial we used the same amount of material that we had been using previously using. The results were extremely great. The flow rate had increased significantly and also the organic solution was filtered right out. In the fourth trial, we increased the sand mass, in order to, filter out larger volumes of water at one time. The activated charcoal was decreased slightly because we realized that a lot of it causes it to clump together and that is because it heavily absorbs the water. We increased the chunky charcoal, in order to mitigate the metal solution and reduce the bluish color. 

       We did not realize, but the previously absorbed solution was still trapped in the mixture, so more of the solution was present that we had initially thought. In the video above, it shows the filtration of our design. 

       In the table below, is the calculated flow rates from the trial tests. 

	Velocity of Liquid (mL / min)	Area of Channel (in^2)	Flow rate
Trial 1	2.42	44.96784147	108.8221764
Trial 2	3.27	44.96784147	147.0448416
Trial 3	1111.1	67.42772672	74918.94716
Trial 4	22.42	67.42772672	1511.729633

       Next week, we will continue testing the metal solution and we will move onto the bacteria solution testing.