Define a Problem
A Gantt chart allows the project to be completed in a timely manor. It's a schedule of everything that needs to be done and when it is to be done. Dividing up responsibilities allows each person to focus on certain things to make sure everything gets done.
Alex- building, materials, sketches, sabotage others
Marley- testing turbidity, pictures, research, sabotage others
Water purification is needed around the world to make water drinkable. Water filters can be very expensive and not accessible to people in very rural areas. This project's goal is to make an inexpensive water filter that can make drinkable water from water with a very high turbidity. Turbidity is the measure of clarity of water. Turbidity is visible at more than 5 NTU. Drinkable water has a turbidity of .5-1.0 NTU. Our water filters had to be constructed from inexpensive materials, reduce the turbidity of dirty water, purify 100 mL of water quickly, be durable and not require extensive maintenance, be easily assembled, and attach to a water catching device.
Marley- testing turbidity, pictures, research, sabotage others
Water purification is needed around the world to make water drinkable. Water filters can be very expensive and not accessible to people in very rural areas. This project's goal is to make an inexpensive water filter that can make drinkable water from water with a very high turbidity. Turbidity is the measure of clarity of water. Turbidity is visible at more than 5 NTU. Drinkable water has a turbidity of .5-1.0 NTU. Our water filters had to be constructed from inexpensive materials, reduce the turbidity of dirty water, purify 100 mL of water quickly, be durable and not require extensive maintenance, be easily assembled, and attach to a water catching device.
Brainstorm
- Cotton and charcoal
- Coffee Filters
- Cloth
- Surgical felt
- Shoe insert
- Coffee Filters
- Cloth
- Surgical felt
- Shoe insert
Research and Generate Ideas
Existing Solutions
Brita water filter Pros: Filters out Zinc, Cadmium, Chlorine, Copper, Mercury; used adsorption (particles adhering to surface) to get out unwanted materials; Cons: Only faucet filter removes majority of particles; used mainly for tap water not in rural areas; not extremely expensive, but may be out of reach for poorer countries https://www.brita.com/ Lifestraw Pros: no chemicals; forces out particles by forcing water through a fiber membrane; acts like a straw- put in unclean water and drink from the other end; given to third world countries; immediate clean water Cons: expensive for those that have to buy it; doesn’t make any spare water http://www.buylifestraw.com/en/products/lifestraw-personal Solarball Pros: inexpensive; easy to transport; makes three quarts at once Cons: takes time to purify http://inhabitat.com/hamster-ball-shaped-solarball-uses-the-sun-to-purify-water/ |
Explore Possibilities
Select an Approach
Detailed Sketch
Make a Model
Test and Evaluate the Design
We used a water bottle as the base for our design. The bottom of the water bottle was cut off and situated inside the rest of the bottle as a holder for the filtering materials. Our first design had three pieces of cloth and a coffee filter. The turbidity was 88.2 NTU. We took out the coffee filter and added surgical cloth and the turbidity went up to 106.8 NTU. Many of our tests resulted in a visibly higher turbidity, so we didn't bother to test it. With cloth, cotton, and a coffee filter we got the turbidity to 41.1 NTU. After cleaning the cotton and adding surgical fabric, it went to 36.3 NTU. Adding another coffee filter at the bottom dropped the turbidity to 21.0 NTU.
Refine the Design
Shoe insert, coffee filter
Shoe insert, coffee filter, cloth
Coffee filter, cloth
Cloth, surgical cloth
Cloth, surgical cloth, cotton
Cloth, surgical cloth, cotton, charcoal
Cloth, cotton, charcoal
Cloth, cotton, coffee filter
Cloth, cotton, surgical cloth
Cloth, cotton, surgical cloth, multiple coffee filters
Cloth was one of our best filters, so we use continued to use it. We tested with and without cotton and found it beneficial. Using the same piece of material multiple times lessened it's effectiveness. Charcoal had limited advantages, so we opted to eliminate it. Coffee filters were also very helpful and we utilized as many as possible.
Shoe insert, coffee filter, cloth
Coffee filter, cloth
Cloth, surgical cloth
Cloth, surgical cloth, cotton
Cloth, surgical cloth, cotton, charcoal
Cloth, cotton, charcoal
Cloth, cotton, coffee filter
Cloth, cotton, surgical cloth
Cloth, cotton, surgical cloth, multiple coffee filters
Cloth was one of our best filters, so we use continued to use it. We tested with and without cotton and found it beneficial. Using the same piece of material multiple times lessened it's effectiveness. Charcoal had limited advantages, so we opted to eliminate it. Coffee filters were also very helpful and we utilized as many as possible.
Conclusion
This project reintroduced us to the design process and tested our ability to build a water filter out of common items. Over the course of the week, we tested materials and combined them in order to reduce the turbidity the most we could. We got our water filter to the point where it filtered water to have a 21.0 NTU turbidity, While this is by no means drinkable, it's a far cry from the turbidity of contaminated water we started with. In this project we learned how to test materials, record results, and make revisions to best improve our design. We also learned what kinds of materials work the best for water filtration. Next time, we could be more systematic about how we made changes. Sometimes, we made multiple changes to our design between tests so it was sometimes difficult to determine which material we altered made the turbidity higher or lower. We also could have recorded our turbidity results better. It was sometimes difficult to discern one result from the next when the prototypes are named by number rather than materials. That made it difficult to go back and see what worked the best.