When chemical engineering major Jocelyn Gonzalez ’16 got the opportunity to work on the cutting edge of desalination research through MIT’s Undergraduate Research Opportunities Program (UROP), she found herself making real progress toward solving an all-too-real problem. Water scarcity is severe, and is worsening, with more than 1.5 billion people living in regions with insufficient fresh water. Since salt water makes up 97.5% of all water globally, desalination—the process of removing salt—holds great promise for water-starved areas from Africa to the Southeastern United States.
This past year, under the supervision of Professor John H. Lienhard V, director of the Abdul Latif Jameel World Water and Food Security Lab, Gonzalez investigated ways to improve the performance of membrane distillation, a thermal desalination method based on the principle of evaporation.
“The way it works is you have the hot saline water that runs through on one side, and the membrane only lets water vapor go through. It rejects liquid water and the salts. Vapor condenses on the cool surface on the other side. That’s how you get clean water,” Gonzalez explains.
Membrane distillation can be more cost-effective overall than other desalination techniques because it can operate at very low temperatures and therefore requires less energy input. However, the membranes themselves are expensive and subject to fouling by biological matter such as algae, which can hinder adoption of the technology.
For her UROP project, Gonzalez helped design an experiment to test a way of combatting the fouling of membranes. The new technique exposes the membrane to air periodically, which discourages alginate deposition. The results, she says, were “stellar.”
Gonzalez’s contribution earned her co-authorship on a research paper as well as the opportunity to present the work at the American Water Works Association’s annual conference and exposition, held this past June in Anaheim, CA. This research, co-authored with Lienhard, postdoc David Warsinger, PhD student Jaichander Swaminathan, and fellow UROP Sarah Van Belleghem ’15, received a best poster award at the conference.
“Working in this lab has been an eye-opener for me,” says the Texas native. “In the near future I think membrane distillation will play a big part in water sustainability.”
This research was conducted in the Rohsenow Kendall Heat Transfer Lab in the Department of Mechanical Engineering, and was supported by a grant from the MIT and Masdar Institute Cooperative Program.
For another profile of a UROP student, the School of Architecture + Planning’s Frankie Perone, look for the forthcoming Fall 2015 issue of MIT Spectrum.