A Choking Cavitation Method and Equipment for Degrading Pollutants in Wastewater

Abstract

A cavitator, with a structure of an annular conical aperture, a throat and a collapse cavity, was proposed to form a choking cavitation flow for pollutants degradation in wastewater treatment. Experiment was conducted in this new cavitator to investigate its flow characteristics and pollutant degradation ratio by employing Mythylene blue (MB) as a pollutant in pure water. It was found that choking cavitation flow appears in the throat by controlling the pump pressure and liquid flow rate in a rule. The pollutant degradation ratio in choking cavitation flow is much larger than that in normal cavitation flow, because plenty of cavitation vapours are born, grow up, and finally collapse in this cavitator in the choking cavitation condition. Gemetrical parameters also affect pollutant degradation ratio, and the optimal gemetrical parameters for this proposed cavitator are suggested.

Keywords

• cavitation
• choking flow
• degradation
• throat
• pollutants