Development of airlift bubble column dispersed with micro-bubbles
Micro-bubbles were dispersed in the bubble column with draft tube, and the length and diameter of draft tube were changed. The flow characteristics in air-water system were measured. Ozone gas and methylene-blue aqueous solution were used, and the decomposition performance was examined. With increasing draft tube length, both the gas holdup and liquid velocity in the annular section increased. When the diameter ratio of draft tube to column was about 0.5, both the gas holdup and liquid circulation flow rate had maxima. For the decomposition by using ozone, the installation of draft tube enhanced the mass transfer and decomposition performance.