It is found that the defects of single-impeller configurations are alleviated and the dual-impeller configuration consisting of upper Rushton impeller for surface aeration and lower upward-pumpi.

• 针对单层桨表面曝气反应器吸入气体主要集中在反应器上部的缺陷,构建了5种双层桨表面曝气反应器构型。