Research papersBacterial inactivation in artificially and naturally contaminated water using a cavitating jet apparatus

•The use of chemicals in water is under scrutiny, due to the formation of byproducts.•Alternative bacterial inactivation techniques are necessary, such as the cavitating jet apparatus.•Chemical reactions in water can occur during the cavitation phenomenon.•Different testing configurations produce different inactivation efficiencies.•The cavitating jet apparatus inactivate more than 90% of E. coli in artificially and naturally contaminated water.

The quality of water for human consumption can be improved by pollution control and by increasing the efficacy of disinfection techniques. The use of chemicals in water treatment is under scrutiny, primarily because of the byproducts generated in this process. Therefore, an alternative procedure to reduce the use of chemicals in this process is necessary. In this study, we demonstrate an alternative procedure for the inactivation of Escherichia coli in water using a cavitating jet apparatus at various pressures and with cooling systems made with various materials. The tests were performed at the Laboratory of Hydraulics and Fluid Mechanics, University of Campinas (Unicamp), Brazil. In tests with various E. coli concentrations, we achieved more than 90.00% inactivation after 900 s of testing time at a pressure of 10.00 MPa. Depending on the available budget and time requirements, diverse setup configurations can be applied. The installation and operation of this system are simple and economical, and the system requires little maintenance, making it useful for the inactivation of E. coli.