Define/discover

At the end of last week and beginning of this week, we worked together in a team to brainstorm, plan and come up with a prototype of a water filter that makes the water okay to pour into the Pitt river using a 2L plastic bottle and a couple other materials in class. Our goal was to release this water into the ecosystem in Pitt river without harming the wildlife. (Even though we didn’t actually do it) This is what my group came up with…

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Dream

We did a little bit of research and though of cutting off the bottom of the bottle to use and a cup to collect our water at the end of the filtration process. We decided that we need some way of collecting big particles first, and then add different materials in the middle to filter and excess small particles and at the end have a way of making sure the materials we used in the middle do not make it to the clean filtered water. Our goal was to make almost if not completely clear water and also get rid of the smell. (the original water smelled like vinegar.)

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Design/deliver

(observations)

We created three filters, all with different designs. For our first one we used a couple of websites and a video to gather a general idea of what the filter would look like although we mostly learned from our own experiences and prototypes. After we thought and brainstormed we wrote our design down on a whiteboard. Here’s how it looked like:

We figured we would want some sort of cloth or net on the top to gather all the big particles and dirt, then we just placed the beads, carbon and sand to catch any more particles. We thought that the filter paper would make sure that the other materials didn’t clog the sponge or go out on the other side of the filter. The sponge seemed like a good idea because it would be really hard to get sand or something else through it plus we all seemed to like the way it absorbed the water that was coming out and made it slow down.

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Once we finished planning, it was time to build it. We followed our diagram and we realized the we planned to use too many materials so we used less than we planned. (which still turned out to be a lot) This is how our prototype looked like:

Our cheese cloth successfully gather excess particles but what we realized was that our other materials mixed together. We thought of dividing the materials from the final water, but we should’ve probably thought of dividing the layers we made. Our water was slightly yellow and the ph levels didn’t really change I made a chart of our observations and materials:

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For our second prototype, we decided to divide the layers with filter paper to avoid what happened the first time and it worked. we used quite a bit less materials because we didn’t want to waste more and we actually used some of the carbon we were able to get from the first prototype. We didn’t use the cheese cloth and instead used filter paper which we thought would be even better and would clean out more particles. we didn’t use a sponge and only filter paper because we wanted to see what would happen if we didn’t have it since it didn’t seem to be doing much. We also removed crystals beads and we agreed to this because the sand is finer and we thought it would gather more particles anyways. We use a rubber band the add a second filter paper- just in case. We also added cotton balls to keep the sand away from the final filter paper and I had also read something about cotton and it was good for filtering water so I wanted to see if it was true. This was our diagram:

In the diagram I didn’t label each filter paper but there was one on the top, and then one in between each layer.

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We built the prototype and again we used a smaller amount of materials than shown, but it was enough to cover a layer. This is what it looked like:

The materials weren’t really visible since we used filter paper between the layers. Anyways, after testing the second filter we found out our idea was a success! The filter paper seemed to work really well. It was so fine and the water was pretty much clear! Here is a picture of the water we filtered and clean tap water (the Erlenmeyer flask contains the tap water and the section of the water bottle contains our filtered water):

The two look almost clear! the smell this time was also more bearable and in general this prototype was the most successful! Here are some observations:

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For our third and final prototype we wanted to do something more simple. Since the second one was so great, we decided that we could experiment with different aspects of both filters. We decided to add the cheese cloth again since it did the job last time and we didn’t use as many filter papers. We used the sponge again in order to experiment with new things but there were no cotton balls. Our diagram for the third prototype looked like this:

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After we were done planning, it was time to build it.  We didn’t use much sand because there wasn’t enough left but we also reused some of our old sand. We decided to not divide layers this time because the sand was so little. This is what our prototype looked like:

We used a hair tie to secure the cheese cloth but it honestly could have also been a rubber band it’s just that we couldn’t find one at the moment. The water that filtered through was not the best quality. Pretty much the only thing that changed was that there were less obvious particles and all the big pieces and dirt were in the cheese cloth. The smell didn’t change and same with the ph level. Here are some observations:

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Debrief

I think that maybe the reason that the third prototype didn’t work was that we didn’t really use fine materials only the big pieces of carbon and the sand was so little that I don’t think it had an effect on the water. I don’t think the sponge does anything and I think that using only one filter paper was a mistake. The second one was a big success and I think that this is because of all the filter paper we used. Filter paper collects even the smallest particles and the fact that the water went through filter paper between the layers might’ve also made the layers more effective because every time the water entered a new layer more particles had been cleaned out. I also think that the sand was a really good material because it is really fine and it collects more particles from water than the big pieces of carbon would ever. Maybe if we used the smaller carbon pieces it would’ve been better…I still have a lot to learn, but I think this was okay. It was definitely not a success. The second one maybe, but this mostly just helped me learn from my experiments and helped me predict with more accuracy what would be most effective. 

 

Sources:

Instructables. “Simple Water Filter Out of a Waterbottle.” Instructables, Instructables, 27 Oct. 2017, www.instructables.com/id/Simple-Water-Filter-out-of-a-Waterbottle/.

Person, and wikiHow. “How to Make a Water Filter.” WikiHow, WikiHow, 22 Nov. 2019, www.wikihow.com/Make-a-Water-Filter.