Treatment of Organics Contaminated Wastewater by Ozone Micro-Nano-Bubbles

Abstract

The efficiency of ozone for the treatment of organics contaminated wastewater is limited by its slow dissolution rate and rapid decomposition in the aqueous phase. Micro-nano-bubbles (MNBs) are a novel method to prolong the reactivity of the ozone in the aqueous phase, thereby accelerating the treatment of the contaminant. In this study, the effects of pH and salinity on the treatment efficiency of ozone MNBs were examined. The highest efficiency was observed in weak acidic conditions and an increase in salinity enhanced the treatment efficiency significantly. Furthermore, the treatment of highly saline industrial wastewater as well as multi-contaminant groundwater containing persistent organics were also investigated. Treatment using ozone MNBs had a considerable effect on wastewaters that are otherwise difficult to treat using other methods; hence, it is a promising technology for wastewater treatment.