A Novel Surface Aeration Configuration for Improving Gas-Liquid Mass Transfer

Abstract

Abstract: A novel surface aeration configuration featured with a self-rotating and floating baffle
(SRFB) and a Rnshton disk turbine (DT) with a perforated disk has been developed. The SRFB,
consisted of 12 fan blades twisted by an angle of 30° to the horizontal plane, is
incorporated onto the impeller shaft to improve gas entrainment, bubble breakup, mixing in
a φ154 mm agitated vessel. This new configuration is compared to the conventional DT
surface aeration experimentally. The results suggest that the critical impeller speed for
onset of gas entrainment is lower for the new configuration and it demands greater power
consumption. Moreover, the SRFB system produces 30%-68% higher volumetric mass transfer
coefficient per unit power input than that obtained in the conventional DT surface aerator
under the same operation conditions.

Key words: surface aeration, self-rotating and floating baffle, gas-liquid mass transfer

摘要： A novel surface aeration configuration featured with a self-rotating and floating baffle
(SRFB) and a Rnshton disk turbine (DT) with a perforated disk has been developed. The SRFB,
consisted of 12 fan blades twisted by an angle of 30° to the horizontal plane, is
incorporated onto the impeller shaft to improve gas entrainment, bubble breakup, mixing in
a φ154 mm agitated vessel. This new configuration is compared to the conventional DT
surface aeration experimentally. The results suggest that the critical impeller speed for
onset of gas entrainment is lower for the new configuration and it demands greater power
consumption. Moreover, the SRFB system produces 30%-68% higher volumetric mass transfer
coefficient per unit power input than that obtained in the conventional DT surface aerator
under the same operation conditions.

关键词: surface aeration;self-rotating and floating baffle;gas-liquid mass transfer

YU Gengzhi, MAO Zaisha, WANG Rong. A Novel Surface Aeration Configuration for Improving Gas-Liquid Mass Transfer[J]. .

禹耕之, 毛在砂, 王蓉. 改善气液传质的新型表面曝气装置[J]. CIESC Journal.

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