Study on the efficiency and mechanism of ozone micro-nano bubble system degradation of Geosmin

A laboratory-scale study was conducted to investigate the degradation of Geosmin (GSM) utilizing an ozone micro-nano bubble system. The primary objectives of this research encompassed: (1) assessing the comprehensive characteristics of the ozone micro-nano bubble system, (2) evaluating the removal of GSM in water samples using the micro-nano bubble system, and (3) identifying the degradation pathways and primary intermediate products generated by GSM during the degradation process. The ozone micro-nano bubble system was compared with the conventional ozone bubble system in terms of initial particle size distribution, liquid phase ozone concentration, free radical generation efficiency, as well as ozone absorption and utilization rates. Furthermore, the elucidation of the degradation pathways for GSM was achieved through rigorous analysis of intermediate product formation. The comprehensive performance of the ozone micro-nano bubble system is better than that of the ozone traditional bubble system. The ozone absorption rate reached 95 % and the ozone utilization rate reached 91.25 % under the ozone micro-nano bubble system. It is worth noting that in pure water, the GSM removal rate of the micro-nano bubble system is 97.11 %. All in all, the ozone micro-nano bubble system can significantly enhance the utilization rate of ozone and improve the removal effect of pollutants. However, there are still some defects in the stability of the bubble particle size produced by the ozone micro-nano bubble system, which poses the next challenge we need to face.