Improved C1 Ion Capture by Acoustically Enhanced Dry CaO Scrubbing, 1997 Environmental Conference Proceedings

An entrained flow reactor was constructed to conduct the CaO/HCl reaction in an acoustic field of 160 dB in an attempt to increase the extent of reaction by removing gas-film limitation. Several reaction parameters were examined. Three mass mean particle size fractions (4, 56 and 91µm) and three reaction temperatures ( 125, 200 and 350°C) were investigated.

Results show that reaction conversion increased 86% at 200°C and SO% at 350°C for the 56 µm mass mean diameter fraction at reaction times less than 1 s. Conversion for the 91 µm mass mean diameter fraction did not change at any temperature. The 4 µm mass mean diameter fraction did not show any statistically significant reaction conversion improvement in an acoustic field. Mercury porosimetry results for the smallest CaO fraction exhibited a decrease in particle porosity indicating the onset of product layer diffusion control. The reaction conversion improvement in a resonant acoustic field was found to be due to additional particle residence time in the reactor.