Small Bubbles Offer Big Benefits

摘要

RESEARCHERS AT the University of Sheffield, Sheffield, U.K., have devised a way to generate far smaller bubbles than previously possible — 20-u dia. in contrast to the 1-3-mm. dia. of conventional fine bubbles (Figure 1). The microbubbles, because of their much higher surface area per unit volume, can achieve 50-fold-greater mass transfer rates and yet take up-to-18% less energy to produce, says Will Zimmerman, a professor in the department of chemical and process engineering and co-inventor of the device for generating them. They may enhance many gas/liquid systems where bubbles are used for mass and heat transfer, keeping materials in suspension or separating them by flotation.