Study of Bromate Formation and Control by Ozonation-Biological Activated Carbon Process

The formation of bromate by ozonation-biological activated carbon process is a problem of drinking water treatment. By pilot test, the influence of bromide ion concentration, contact time of ozone column, ozone dosage, Ct value, changes of water quality and adsorption time of activated carbon column on bromate formation and control were investigated. The results showed that when [Br^-]=100~500¿g/L, t=3~15 min, the process operating parameters could be adjusted to control the concentration of BrO₃ ^- which did not exceed the amount of 10¿g/L. The changes of TOC, UV₂₅₄, temperature, ammonia nitrogen, pH would affect the concentration of BrO₃ ^- formation. When the adsorption time of biological activated carbon column reached 20 min, the average removal efficiency of BrO₃ ^- could achieve 62.24%. When [Br^-]¿300¿g/L, the Water quality of ozonation-biological activated carbon process could meet the requirements of [BrO₃ ^-]<10¿g /L.