For their senior capstone project, which was sponsored by The Dow Chemical Company, a team of mechanical engineering students from Northwestern University in Chicago, Illinois, researched something that has major economic consideration for the industrial cleaning industry - the upper cleaning limits for industrial hydroblasting. In other words, when, or if, does high-pressure water start to cause harm to the integrity of the tubes in industrial processing equipment?
These are important questions for companies like Dow, who rely on the efficiency of their heat exchanger bundles to deliver optimal productivity at their chemical plants across the world. It's also vital information to Veolia, who is contracted by Dow and other major industrial companies to perform industrial cleaning on these exchangers using high pressure water.
The Northwestern students designed and built a test rig to objectively apply high pressure water to an array of metal coupons - flat, square pieces of different types of metal. The rig delivered various combinations of pressure, flow rate and linear velocity with respect to the nozzle, and was tested at a Veolia operating location in Hammond, Indiana. Thanks to Veolia's long-standing relationship with Dow, we were able to mentor the Northwest students for nearly a year through their capstone project, providing them with insights, information, equipment and field support to test their hypothesis.
The results of the students' tests unearthed some interesting findings and provided a meaningful foundation for additional testing and analysis. In essence, what they found was that with significant dwell time – one continuous stream of high-pressure water applied to the same exact location, over an extended period of time – even "clean" (potable and demineralized) water may in fact have the potential to negatively impact heat exchanger tube metallurgy. And while additional testing and analysis is required to support this finding, Veolia is a proud partner to Dow and these students who are working to improve our business through science and engineering.