The Project:
This project was fairly open-ended. Each group had to come up with their own driving question and design or propose a project involving water for the North Bay Science Discovery Day. Our group focused on chemically treating dirty water to get clean water. Our driving question was "How can we create a cheap, effective, and small water filtration system?" We decided to make a simple water filter out of a soda bottle using only cotton balls, sand, and activated charcoal. The cotton balls removed the larger particles, the sand filters the water without the use of chemical aids and reduces number of bacteria, and the activated charcoal removes toxins from the water. After it goes through the filter we will put the water through ultraviolet filtration to kill any surviving bacteria making our water more clean.
Presentation:
Content:
ph
In chemistry, pH is a scale used to specify how acidic or basic a water-based solution is. Acidic solutions have a lower pH, while basic solutions have a higher pH.
ph scale
A pH value is a number from 1 to 14, with 7 as the middle (neutral) point. Values below 7 indicate acidity which increases as the number decreases, 1 being the most acidic.
drinkability range
The ideal pH level of drinking water should be between 6 - 8.5.
filtration
Filtration is a method for separating an insoluble solid from a liquid. When a mixture of sand and water is filtered: the sand stays behind in the filter paper (it becomes the residue ) and the water passes through the filter paper (it becomes the filtrate).
activated charcoal
Carbon filtering is a method of filtering that uses a bed of activated carbon to remove contaminants and impurities, using chemical adsorption. It has the ability to improve water by removing disagreeable tastes and odors, including chlorine.
adsorption
Activated carbon works via a process called adsorption, whereby pollutant molecules in the fluid to be treated are trapped inside the pore structure of the carbon substrate. Carbon filtering is commonly used for water purification, air filtering, and industrial gas processing.
ultraviolet filtration
In a UV water filter system, UV (Ultraviolet) rays are used to kill the harmful bacteria from the water. Hence the water is completely disinfected from pathogens.
Reflection:
Overall, I'm pretty impressed by and proud of how our water filter turned out. Our group collaborated really well, and we were able to get enough work done every day that when it came down to presentation day, we weren't at all stressed about our slideshow. I enjoyed that this project had a building/engineering aspect to it, because it felt hands-on, which is reminiscent of our freshman year of STEM. Our group communicated effectively with each other, and we each took on leadership roles throughout the project. One of my favorite, most satisfying parts of this project was seeing how incredibly dirty our water was (we added sticks, dirt, mud, etc. to already dirty pond water) and watching our filter prove not only able to handle it all but produce super clear water! It's always exciting and rewarding to produce and witness such a positive change.
One downfall of our filter was that our design had a leaking point. In the bottom tub, where the filtered water lands, is a spigot. When attaching the spigot, we had to create a hole in the tub that was the exact size of the spigot. Unfortunately, as we didn't have access to the Makerspace, we couldn't access the circle cutter, which would have produced a more precise cut. Instead, we had to use an x-acto knife, which wasn't very efficient or neat, and we ended up with a leaky seal. This not only made a mess on the counter but also threw off our tests, as we wanted to record the ratio of dirty water going into the filter to clean water coming out of the filter (we knew the cotton balls would absorb some of the water and wanted to calculate how much). Another pitfall of this project was that we could have used more critical thinking skills. Although we were very satisfied with our outcome, we didn't think of many other creative solutions or further ways to improve our filter. For future projects, once we figure out something that works well, I intend to dig deeper and make our design even better. We did have limited time with this project due to CAASP and AP testing, so I'm plenty pleased with our results.
One downfall of our filter was that our design had a leaking point. In the bottom tub, where the filtered water lands, is a spigot. When attaching the spigot, we had to create a hole in the tub that was the exact size of the spigot. Unfortunately, as we didn't have access to the Makerspace, we couldn't access the circle cutter, which would have produced a more precise cut. Instead, we had to use an x-acto knife, which wasn't very efficient or neat, and we ended up with a leaky seal. This not only made a mess on the counter but also threw off our tests, as we wanted to record the ratio of dirty water going into the filter to clean water coming out of the filter (we knew the cotton balls would absorb some of the water and wanted to calculate how much). Another pitfall of this project was that we could have used more critical thinking skills. Although we were very satisfied with our outcome, we didn't think of many other creative solutions or further ways to improve our filter. For future projects, once we figure out something that works well, I intend to dig deeper and make our design even better. We did have limited time with this project due to CAASP and AP testing, so I'm plenty pleased with our results.