An Application of Orifice Hydrodynamic Cavitation Reactor for Tertiary Treatment of Wastewater Treatment Plant Effluents

In this paper, a multi-orifice hydrodynamic cavitator (HC) has been applied as an effective device for water reclamation. Municipal wastewater after mechanical and biological treatment has been applied as a medium. The effectiveness of using this device has been evaluated on the basis on the microbiological indicators. Moreover, optimization of operating parameters was evaluated. Two experiments with different inlet pressure of 0.4 and 0.6 MPa were performed. The samples for analyses were taken at the following time intervals: 0, 15, 30, 60 and 90 min. The application of HC reactor provided the effective destruction of microorganisms, thus allowing for subsequent use of reclaimed water. With regard to Escherichia coli and Coliform bacteria destruction, the longest time of 90 min and higher pressure of 0.6 MPa might be considered as the most advantageous conditions to perform cavitation. In both cases, the microbes were deactivated in over 50%. In the case of Enterococci, Pseudomonas aeruginosa and colony count, more beneficial results were found at lower pressure of 0.4 MPa and 90 min. Therein, the high level of microorganisms destruction was achieved varied between 81 and 92%. The applied HC allowed for selecting optimal operating parameters and process control through the application of gauge system