Imaging inside reactors

Ohio State University researchers have invented a technique to record three-dimensional scans of the gases and solids that mix inside boilers and other industrial processing reactors.

Scientists can use the patented technique, called electrical capacitance volume tomography (ECVT), to observe how the density of materials varies inside a reactor. The end result could be better monitoring of reactor systems, including power plants.

L.S. Fan, a Distinguished University Professor and the John C. Easton Professor of Engineering in the Department of Chemical and Biomolecular Engineering at Ohio State, said, “Hospitals use tomography to view areas of the body that aren’t easily or safely accessible, and the interiors of boilers and other high temperature reactors in industry are similarly inaccessible.”

Fan studies the processes for converting coal to liquid fuels and chemicals, in order to optimise the energy conversion efficiency while reducing power plant emissions.

“Right now, the way to convert coal or natural gas to liquid fuels is in high-temperature, high-pressure reactors,” Fan said. “But if we’re going to develop processes to achieve high energy conversion efficiency, we need to be able to see inside those reactors to know how they work. That’s why we developed ECVT.”

The invention includes a sensor system that measures the capacitance, or the ability to store an electrical charge, of the materials inside the reactor. Software then converts those measurements to information about the materials’ composition.

Materials flow inside these hot reactors in complex ways. So the key to making ECVT work is a visualisation system that presents the rapidly changing data accurately in three dimensions.

Other techniques produce two-dimensional images, or less accurate images. But ECVT gives scientists the accurate three-dimensional images they need to manage the industrial chemical reactors in real time.