Evaluating a high‐efficiency ozone injection contactor

With sidestream venturi injection and a specially designed downflow tube, this recently developed ozone contactor is an attractive alternative to the fine‐bubble diffusion contactor for high ozone concentrations. A new type of ozone contactor, called the SVI‐DT (sidestream venturi injection with downflow tube) contactor, was evaluated at pilot scale and compared with the performance of a traditional countercurrent flow, fine‐bubble diffusion contactor. The specially designed downflow tube, equipped with one or more pressurized sidestream venturi injectors and installed inside an ozone reactor, facilitated the dissolution of ozone into water. The results showed that the SVI‐DT contactor achieved high mass transfer rates and outperformed the fine‐bubble diffusion contactor in removing color and yielding higher and longer‐lasting dissolved ozone residuals. The hydraulic behavior of the new contactor was also evaluated, and operating limits were established for maintaining stable two‐phase flow conditions in the downflow tube.