Research on the cavitation characteristics and disinfection performance optimization of a rotor-radial groove hydrodynamic cavitation reactor

Abstract

Rotary hydrodynamic cavitation reactor is widely used in the field of water treatment because of its excellent cavitation performance. A new type of arc rotor is presented in this paper. The effects of different rotation speeds and width of stator cavitation generating units (CGUs) on cavitation characteristics of a rotor-radial groove hydrodynamic cavitation reactors are discussed. Cavitation bubble volume, cavitation phenomenon of the stator and rotor domains in the reactor were used to characterize the cavitation characteristics. A hydrodynamic cavitation disinfection experimental system was set up to disinfect the Escherichia coli solution. Take samples every 9 minutes for a total of three times. The disinfection rate of E. coli was used to characterize the disinfection performance of the reactor. The results show that more intense cavitation is caused on the surface of the arc rotor and in the CGUs of the stator. At 3600 rpm, 3900 rpm and 4200 rpm, the cavitation bubble volume in the reactor was increased by 196 %, 301 % and 240 % respectively. The stator CGU width is 1.8 mm, the cavitation intensity is maximum. The reactor with the arc rotor was operated at a speed of 3900 rpm for 27 minutes. The sterilization rate has increased by 17.7 % compared with the original rotor under the same working conditions. The arc rotor greatly optimizes the cavitation characteristics and disinfection performance of the reactor. It promotes the further development of hydrodynamic cavitation in the field of water treatment.

Keywords

• Arc rotor
• Hydrodynamic cavitation reactor
• Cavitation characteristics
• Disinfection performance
• Optimization