MEDRIX UV Water Treatment System
ME Undergraduates Make a Difference
What do Bill Gates and his foundation have in common with a group of UW Mechanical Engineering undergraduate students? A goal of “improving world health by bringing innovations to the global community.” In the ME students’ case, it meant improving water treatment systems in rural Vietnam.
It all began in 2006 as an undergraduate capstone design project for seniors, in which their fundamental knowledge culminates in a real-world design experience. A perfect opportunity arose when ME Professor Ann Mescher teamed up with Bob Catherman of MEDRIX on a potential project.
MEDRIX is a Redmond, Washington-based non-profit organization that works primarily in Vietnam to provide health care, education, and safe drinking water in rural communities. The company saw first-hand throughout Southeast Asia that the lack of safe water severely impacted the quality of health, and that access to safe water would help solve many of these problems. MEDRIX discovered that more water was not needed to improve health; it was better quality water.
MEDRIX has been working on an Ultraviolet (UV) Water Treatment System, a treatment method that has been in use for nearly 100 years, but unavailable at an affordable price for the poor. The company was interested in improving the design of its water treatment system as well as achieving the following goals: 1) simple but effective, 2) affordable, and 3) buildable in-country by micro-enterprises.
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Megan Lew, Bryan Speare and Megan Karalus |
Three ME students, then seniors—Megan Lew, Bryan Speare and Megan Karalus—answered the challenge, and collaborated with MEDRIX for several quarters in 2006–07 to refine the design of the existing UV water treatment system. What attracted them to this particular undertaking? “I was looking for a real-life project with a non-profit, service-oriented company,” said Megan Karalus. “I wanted to help people,” explained colleague Megan Lew, “and this was a project that interested me.” Bryan Speare stated, “The project sounded like a good opportunity to really make a difference.”
Professor Mescher guided the interactions between the students and Bob Catherman to determine the project’s scope, develop an engineering analysis and plan, and create a functioning prototype of an improved UV water treatment system. Through flow visualization experiments and computer modeling, the students conducted mixing studies and stress analyses that enabled significant design changes. They participated in blogs from trips to Vietnam, which illustrated the constraints in a third world country, but more importantly, allowed them to see the project’s progression.
Specific goals of the design team included improving UV dosage by developing flow turbulence during water treatment, studying the current system’s optics to simplify construction of the reactor chamber, and improving the load-bearing characteristics of the stand that supports the treatment chamber and the treated water reservoir.
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Girl with UV system in Phu Ho |
Outcomes of their design included reducing the number of system parts by 25 percent with no sacrifice in stability or strength. The flow study resulted in structural modifications that improve mixing while also decreasing construction complexity. Testing of the final prototype confirmed that the system met the design functional requirements, successfully providing safe water at flow rates ranging from 0.4 to 3.6 liters per minute.
As a result of the work completed by the team, MEDRIX made changes to the templates describing how to construct the flow-directing baffles in the system and then went to the effort of retrofitting systems already installed to take advantage of the benefits from the design changes.
Working on a real-world project presented some challenges. “We had to deal with budget and design constraints, and the directive of ‘simple and cheaper’,” said Megan Lew. “It was difficult that our users in Vietnam were so distant, but we learned how to apply the different engineering analysis tools studied in class for a real client,” said teammate Megan Karalus.
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Bob Catherman of MEDRIX with students |
From all fronts, the collaboration was successful. “My expectations were met 110 percent,” said Bob Catherman. “I was impressed with the quality and knowledge of the students. They listened carefully and were not afraid to ask questions.” “It was a great team,” exclaimed Lew, “Bob was always available and was happy with the project.”
The best part? “Working with Megan and Bryan,” claimed Lew. “This experience helped me decide to pursue graduate study in global health and medical devices.” According to Karalus, “Meeting the client’s needs. It was a wonderful experience.” Speare agreed, “It was great to see our efforts pay off. We made improvements that can help the client reach more people.”
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Teacher and child in Phu Ho |
The success of this project spurred a new group of undergraduates—Darin Allen, Gina Hicks, Jordan Lee, Brandon Smith, and Nicholas Stanislowski—to pursue a follow-on project with MEDRIX in spring quarter 2008 to study a portable power source for the UV water treatment system.
Learn more about MEDRIX and their safe water development at http://medrix.org/water.html.