Modelling Hydraulics of Ozone Contactors

The U.S. EPA published the surface water treatment rule which imposed stringent requirements for disinfection. The rule is based on the C × T concept. The detention time T10 must be determined for each type of contactor by performing tracer tests. Those tests have been performed for various ozone contactors. The results were evaluated using two types of models. For a classical diffuser-bubble contactor the ratio T10/τ is about 0.5. For an industrial deep U-tube this ratio is equal to 0.55, but it reaches 0.9 for a pilot system. These results are indicating that a deep U–tube can provide a greater T10/τ ratio than a diffuser–bubble contactor.