Investigation of factors affecting oil-water separation efficiency in micro-bubble micro-cyclonic flow air flotation

In this paper, we investigate the impact of various factors of micro-bubble micro-cyclonic flow air flotation technology on the wastewater purification efficiency by combining the effect of swirl separation and flotation. The study was conducted utilizing high-speed imaging and image processing technology to analyze the impact of oil concentration, floc size, and swirl field on the settling time and separation efficiency of oil-water separation in the presence of microbubbles. The results indicate that microbubbles significantly reduce the time required for oil-water separation. Compared to static pure water conditions, the settling time for static separation was reduced by 50 %. The oil concentration was decreased by 38.7 %, 71.4 %, and 76.5 % in microbubble flotation, cyclonic flotation, and flocculant + cyclonic flotation processes, respectively. Interaction experiments involving the three factors revealed that, in terms of oil-water separation efficiency, three-factor coupling is most efficient, followed by dissolved air water and swirl field, and then by dissolved air flotation alone.