Treatment Effect of Microbubble Aeration Technology on Black-odor River Water 

A microbubble generator produced domestically was used to treat the black-odor river water. A comparison study on treatment efficiency between the microbubble aeration and conventional aeration was carried out. Some important water quality indicators, including odorous chemicals (Geosmin and 2-MIB), COD_Cr, NH₃-N, TP, color and turbidity were monitored during the experimental period. The results showed that microbubble generator produced higher DO concentration than conventional aeration under the same gas flow, and DO level produced by the former one was 9.87 mg/L in 60 min but only 6.54 mg/L in 100 min by the latter. During the experimental period, microbubble aeration obtained or was greatly closed to its highest removal rates of different pollutants at 60-80 min, while conventional aeration did not obtained or was greatly close to its highest removal rates until 80min or even later. Additionally, the removal rates of COD_Cr, NH₃-N, Geosmin and 2-MIB coming from microbubble technology were 12%, 10%, 16% and 12% higher than those from the conventional aeration technology, respectively. The color and turbidity values increased at the beginning period because of the strong stirring from bubbles, and did not recover to their initial level until 60-80 min.