This page is no longer being updated and remains online for informational and historical purposes only. The information is accurate as of the last page update.
For questions about page contents, contact the Communications Division.
This year’s Introduction to Engineering class will work with a technology that appears certain to grow in importance: desalination.
Specifically, the students will build small hand-operated pumps that will accomplish desalination through reverse osmosis. “It’s a very standard engineering procedure that can be used on a large or small scale,” say Ed Saliklis, assistant professor of civil and environmental engineering. “This project is going to be small scale, but it will highlight the principles to the students.”
Two tanks of water, one fresh and one salty, will be separated by a thin membrane able to withstand tremendous pressure. Normally, fresh water would flow to the saline side. Pressure will be applied to accomplish reverse osmosis, causing water to flow from the salty side to the fresh one.
The students will build pumps in teams of four or five that will stay together throughout the semester. “That’s one of the goals of the course: to show them that you have to work in teams,” says Saliklis. “We pick the teams, because that’s what happens in the workplace.”
The water will be brackish, or fairly low in salt content, because seawater desalination requires extremely high pressures on the order of 800 pounds per square inch. The students will use pressures of 150 pounds per square inch.
This does not mean that the project is not significant for practical, real-world applications, however. “The reverse osmosis membrane is being donated by a company that is interested in the project,” says Saliklis. “We’re also submitting a publication on the project to the American Chemical Engineering Society because they’re interested in what we’re doing with this membrane technology.”
Reverse osmosis is used by Saudi Arabia to meet about 40 percent of its drinking water needs. While the technology is not new, it has not been used on a large scale to provide drinking water in the U.S. because until recently, it was too expensive. The city of Clearwater, Fla. is bringing a large-scale plant on line in the next year or two. The approach also is under consideration by city officials in Tucson, Ariz.
“Until now, these communities have been taking a lot of drinking water from the aquifer – the underground water table — and depleting it,” says Saliklis. “If they can pull water out of the ocean in the case of Florida or the Colorado River in the case of Tucson, and make it commercially feasible, they have a real solution to a big problem. People are excited about students learning about these new technologies because the impact can be quite large down the road.”
The overall goal of the course is to familiarize students with the four BS engineering majors and AB engineering. Instructors representing each major rotate in the role of class instructor. The project involves all five engineering areas: chemical – the composition and working of the membrane; mechanical – the pumping required to achieve 150 pounds per square inch; civil and environmental – water quality and analysis of stress in the vessels; electrical and computer – setting up the circuit to test water salinity before and after filtration; and AB engineering – larger issues such as what it takes to get a reverse osmosis desalination plant up and running for a community.
“The project touches on all of these areas, but the class lectures are broader,” adds Saliklis. “The students get a sense of what each type of engineer does as they’re trying to decide what major they want to work in, or which they definitely do not want to pursue.”
Students also learn skills such as technical writing and Computer Aided Design, and will make presentations to professionals and outside evaluators who will examine their work. “It’s a real introduction to engineering at a college, and also an introduction to the profession,” says Saliklis.