Experience with the implementation of chlorine dioxide for water disinfection in Mosina Water Treatment Plant

The paper gives an account of the experience gained while implementing chlorine dioxide for water disinfection at the Mosina. Water Treatment Plant, which supplies tap water to the city of Poznan. It was found that when the proportion of the chlorine used so far to the chlorine dioxide being implemented was 50%/50%, this was paralleled by an uncontrolled bacterial growth in the water, which was inhibited by increasing the proportion of chlorine in the mixture of the two disinfectants. Another finding produced by the study was that when both the disinfectants were applied, it was possible to vary the chlorine dose while chlorine dioxide had to be dosed in the same amount. The addition of a new reagent brought about changes in the chemical composition of the water, thus disturbing the balance that had stabilized in the water-pipe network for many years. The process of restoring water stabilization in the pipeline was a long-term one. The large water supply system for the city of Poznan requires efficient actions to prevent water recontamination, as well as a reliable, continuous control of water quality primarily to ensure bacteriological safety. The application of chlorine dioxide alone to water disinfection at the Mosina. Water Treatment Plant without increasing the efficiency of organic matter removal was found to be a failed attempt.