Environmental and Interfacial Transport Laboratories

Research in these labs address problems associated with water quality, wastewater treatment, paper recycling, and materials processing for the environment. Visualization of air-water gas exchange studies seek to discover, characterize, and evaluate physical mechanisms that govern rates of gas absorption across waves, flat interfaces, and bubbles in gas-liquid systems.

Laser-induced fluorescence (LIF) techniques are developed and applied to image oxygen concentration boundary layers occurring in tank and column flow facilities. The LIF systems include nitrogen lasers, high-resolution back-illuminated CCD cameras, UV-enhanced optics, high magnification and long working distance lenses, and image processing capabilities. These facilities allow measurement of oxygen concentration gradients and boundary layer visualization at air-water interfaces. Visualization techniques have been developed for imaging and quantitatively measuring adsorption rates for particle removal at bubble surfaces.

Research involves novel bubble-suspending flow facilities and optical techniques to directly image and quantify particle attachment and removal rates for air bubbles. The suspending bubble facility suspends bubbles in a carefully controlled downflow of water and the stationary bubble facility holds bubbles at the tip of needles in a quiescent fluid. The optical techniques use a high-speed (1000 frames per second) camera, long distance microscope lenses, and image and video processing. The fundamental research characterizes the rates and behavior of the removal of particles (inks and stickies) from water using dissolved air flotation (DAF) and flotation deinking processes. Visualization of particle formation studies seek to discover, characterize, and evaluate physical mechanisms that govern particle formation processes in fluid and supercritical fluid application.

The visualization system includes laser and high intensity light sources, a high spatial and intensity resolution CCD camera, high magnification and long working distance lenses, and image processing capabilities.

Last Updated: Feb 09, 2011