In this study, we investigated the use of ultrasound for the disinfection of process water as an alternative for more traditional techniques, like chlorination and UV-irradiation. A pilot plant was constructed to mimic circulating process water in industrial environments. The disinfection efficiency of ultrasound was assessed and compared to UV-treatment and chlorination. In addition, the operational costs for the different technologies were evaluated. Based on disinfection efficiency and operational costs, the pilot plant experiments indicate that chlorination is the method of preference to treat bacteria in suspension. In the prevention of biofilm formation, the results of UV irradiation and ultrasound are comparable, with a slightly higher energy consumption for the ultrasonic treatment. Finally, the use of ultrasound to prevent biofilms was also evaluated in an industrial environment (case study). The results obtained from the case study are in agreement with the results obtained from the pilot plant study. To our knowledge, this is the first study that evaluates the use of ultrasound technology for prevention of biofilm formation in realistic circumstances as encountered in an industrial environment.
Keywords: biofilm, chlorination, disinfection, process water, ultrasound, UV-irradiation