By Melissa Weisser
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Step 1: Investigate!
After my professor sent me charcoal, alum, gravel, sand, and a cheesecloth to make a stackable water filtration system I wanted to do some research on why she chose these materials. These materials actually were earth-like materials that closely can resemble how water is naturally filtered through the ground.
Step 2: Plan Out You Design!
Before making a drawing, I laid the materials out in the order that I was going to use them in my design. The order of the materials basically went from physical materials that would trap big particles first, to chemical materials to filter out the bacteria. I started with the cheese cloth so I could pick off the big particles before they even went through the system -- I was able to stop the grass at that point. Then I chose the gravel to stop any big particles that still filtered through the cheese cloth. The next layers had coffee filters in between to trap small particles, along with the next layer of sand for the same purpose. When it finally got to the charcoal that was a biological filter, it helped pull out the toxins in the water, and then the Alum which helped to chemically filter the water.
Step 3: Put My Design Into Action!
I used a push pin to push holes through the bottom of each cup. I wrote the name of the material on the outside of the cup since they weren't clear, and then I covered them all with a coffee filter except for the very top cup which got a cheese cloth instead to just trap the bigger particles in my water.
Step 4: Testing My Design
When I went to test my design, I first primed it with just some clean water. It was messy, but water filtered through so I then proceeded with the dirty muddy water. I had to adjust my design after finding out that the coffee filter slowed down the water too much and I only left it on the clean water cup and the alum cup to catch any charcoal. At the end my water was basically clean! It didn't have the muddy color to it anymore. It did have a black tint to it from the charcoal, which I'm thinking I should have primed the charcoal more before adding it to the cup in my design.
Step 5: Reflecting on Making the Design Better for Next Time
I definitely wanted to use a bigger cup or bottle to design my system! I was thinking that I could use a water bottle instead of cups. With the water bottle I would have turned it upside down and cut off the bottom of the water bottle. I would have then laid a coffee filter in the bottom of the bottle (the mouth part that is normally the top) to cover the opening and then I would have just put my layers of earth material on top of each other in the bottle. The only bad part about this is that the earth materials would not be able to be separated again if I wanted to change my design, but the realistic part is that is how they are on the earth.
Step 6: Inquiry Rubric
This activity involved a lot of inquiry because we had to plan, design, and create our filtration system. We also had to investigate background information about what the materials do and how it relates to the natural water filtration system that the earth does. At the end we also had to determine if the problem was resolved, just like engineers would have to figure out in the real world.