Intensification of Ozone Mass Transfer by Microbubbles and Its Effect on Hydroxyl Radical Production
1. College of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China;
2. Chongqing Municipal Solid Waste Resource Utilization & Treatment Collaborative Innovation Center, Chongqing 401331, China
Abstract：In order to improve the mass transfer efficiency of ozone in water, a microbubble reactor was designed to enhance the mass transfer of ozone. The effects of different reactor pressure, temperature, ozone inlet concentration and flow rates on the ozone concentration in the liquid phase and the generation of hydroxyl radicals were investigated. The results indicated that ozone concentration in liquid phase was less affected by the pressure, but the concentration of hydroxyl radicals in liquid phase increased with the increase of reactor pressure. With the increase of inlet ozone concentration and the flow rate, the ozone concentration in the liquid phase increased and more hydroxyl radicals were generated. Increasing the liquid temperature resulted in a reduction of the ozone concentration in the liquid phase, but it increased the amount of hydroxyl radicals produced in the liquid phase. The microbubble reaction system was also compared with the traditional bubbling reactor. The results showed that the microbubble reactor could effectively improve the mass transfer efficiency. When the ozone concentration in the liquid phase reached a steady state, it was about 14 mg/L, which was about 10% higher than that of a bubbling system. The hydroxyl radicals in the bubble reactor were more effectively generated than that in the traditional bubbling reactor. After 5 minutes of ozonation, the hydroxyl radical concentration in the microbubble reactor was as high as 121.45×10-6 mol/L, which was about 11 times higher than that of the bubbling reactor, and both the decolorization and mineralization efficiency of wastewater in the microbubble reactor were higher than that of the traditional bubbling reactor.
Cheng Wen1,Quan Xuejun1,Luo Dan1 et al. Intensification of Ozone Mass Transfer by Microbubbles and Its Effect on Hydroxyl Radical Production[J]. 化学反应工程与工艺, 2017, 33(5): 458-465.
