Preliminary pilot plant study of ozonation and biological activated carbon (BAC) with recycling for advanced drinking water treatment

Abstract

The residual dissolved organic carbon (DOC) from the conventional drinking water treatment is responsible for the production of undesirable disinfection by-products (DBPs) during chlorine disinfection process. The combination of ozonation and biological treatment is promising unit process for residual DOC removal in conventional drinking water treatment. Multi-stage ozonation-biological treatment, which is a repeated process of ozonation-biological treatment, could decrease more DOC than the single-stage ozonation-biological treatment with the same total ozonation time. However, the multi-stage ozonation-biological treatment is not practically feasible to be implemented in full-scale drinking water treatment. A continuous ozonation-biological treatment with recycling, which is an analogous treatment with the multi-stage ozonation-biological treatment, seems to be more applicable in actual drinking water treatment. The objectives of this study are to evaluate the performance of ozonation – BAC treatment with recycling for DOC and DBPs removal, to identify the characteristic changes in ozonation – BAC treatment with recycling and to determine effect of various physical parameters such as temperature, conductivity and pH on ozonation – BAC treatment with recycling.