Engineering Design and Development: Mini Project
Defining the Problem
Objective: Reduce the turbidity of a sample of water by designing an inexpensive, easy to use, and durable water purification system using low cost, readily available materials to quickly remove contaminants from water.
- Turbidity measures the lack of clarity of water, and is a test that is often used to determine the quality of a water sample.
- Turbidity is measured in Nephelometric Turbidity Units (NTU).
- Be constructed from easily acquired inexpensive/free materials
- Significantly reduce the turbidity of the contaminated water
- Purify 100 ml of water in the least amount of time
- Be durable and require the least amount of maintenance
- Be easily assembled
- Be designed to attach to a bucket or other device as designated by your instructor as the clean collection container
Research
We researched existing water purification systems and popular portable water filters. We used examples like these to learn more about the materials commonly used in water filtration systems.
The LIFESAVER® bottle
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Bobble filter water bottles
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Team Organization and Planning
Gantt Chart
Brainstorming and Generating Ideas
We knew that we were limited to using the inexpensive or free materials found in our engineering lab, so we tried to focus on designing a filter that is simple to use, and inexpensive to make. We decided to work with materials including rocks, sand, gravel, cheesecloth/ a tee-shirt, and plenty of duct tape
Narrowing Down Ideas:
We took several things into consideration when weighing the pros and cons of each idea that we generated.
How long it would take for the water to filter
How long it would take to build the filter
Cost of supplies
Difficulty of design
How easy it is to clean/ replace the filter
How much space the filter took up
How long it would take for the water to filter
How long it would take to build the filter
Cost of supplies
Difficulty of design
How easy it is to clean/ replace the filter
How much space the filter took up
Final design
We chose this design because it was the best use of the materials that were available to us in the engineering lab and around the school.
We used layers of rocks of varying sizes, sand, and pebbles to filter the clay out of the water we used. We kept all of the different filtering components in place by duct taping an old tee shirt to the bottom of a tube that we found in the lab. All of the materials we used were either completely free, easy to find, or very inexpensive. |
Testing and Results
Our design was a success because it filtered the water well , however it took several hours to make the muddy water completely clear. This may have been due to the fact that we used clay water for our test. We observed that the clay settled below the water but on top of the filtering materials. We think that this prevented the movement of most of the water through the filter.