AMES, Iowa -- Iowa State University's College of Engineering will demonstrate a new x-ray imaging device used to study part of the paper recycling process during an open house from 1 to 3 p.m. Friday, Nov. 5, in the Transport Processes Laboratory, 1121 Black Engineering Building. The event is free and open to the public.
The imaging system is used to study the interaction of multiphase flows (gas, liquids and solids) in a contained area.
Ted Heindel, who holds the William and Virginia Binger Associate Professorship in Mechanical Engineering, required the specialized industrial imaging device to study the complex processes used to remove ink particles and contaminants from recycled paper.
"The process involves ink particles and air bubbles floating in a fiber slurry, and a lot goes on that we don't understand," Heindel said. "If we're able to learn more about what influences contaminant removal, we can determine how to do it more efficiently and produce higher-quality recycled products."
Heindel said his research goes beyond paper recycling. Multiphase flows also are fundamental to the production of everything from food to fuel to pharmaceuticals.
In order to research multiphase flows, many of which are opaque, Heindel needed a noninvasive device that wouldn't disrupt the flow but still could capture images of what was happening inside the flow. The device also had to be large enough to simulate industrial applications.
Heindel teamed up with Joe Gray, leader of the X-ray group at Iowa State's Center for Nondestructive Evaluation, and Terry Jensen, a center physicist. They designed and built a one-of-a-kind 3-D imaging system. The new mega-instrument was funded through $640,000 in grants from the National Science Foundation's major instrumentation program and Iowa State.
"The device has a complex collection of X-ray hardware, software and housing," Heindel said.
The instrument is a vertical computed tomography (CT) scanner, similar to what doctors use to examine tissues or organs in humans.
"We record X-ray images spanning various locations around the imaging region," Heindel said.
Projections from each orientation are collected and reconstructed by computer, generating images of the cross-section. In addition, the instrument can complete X-ray stereographic imaging, which, when reconstructed, will produce 3-D movies of the multiphase flow conditions.
"Until now, companies have developed computational models, based on crude measurements and assumptions about what is happening inside, to predict the output," Heindel said. "This instrument will help take away that guesswork."
After two years of designing and building the instrument, Heindel said he is eager to see how the knowledge can be applied.
"The field is wide open," he said. "I can see it increasing the efficiency of many processes -- paper recycling, food processing and wastewater treatment, just to name a few."