RESEARCH ON THE GENERATION REGULARITY AND CONTROL MEASURE OF BROMATE IN WATER OZONIZATION BY-PRODUCTS

Objective To study the generation regularity and control measure of bromate which was a kind of by-product in ozone disinfection of drinking water.Methods Iodimetry and ion chromatography were used to determine the concentration of ozone and bromate in water respectively.Results The bromate concentration increased as the bromine ion concentration rose when the venting concentration of ozone approached to 17.67 mg/L.In this reaction system when bromine ion was 0.5 mg/L,bromate concentration achieved 0.014 mg/L.Less bromate was produced by reducing concentration of ozone in water,decreasing both water temperature and water colority,and acid water.With 0.025 mg/L ammonium ion in water,bromate generation was suppressed,and the bromate concentration reduced below the detection limit of this method.Conclusion When disinfecting drinking water with ozone the concentration of bromine ion is the main factor which can affect bromate concentration.Bromate production can be reduced by adding ammonium salt.