Abstract:

A pilot-scale experiment of O₃-biological activated carbon (O₃-BAC) advanced treatment process was carried out for the surface water at levels Ⅱ～Ⅲ in the Dongjiang River, Guangzhou. The removal rules of the con-tamination in the water were then investigated. In the experiment, two processes, namely Process I-pre-ozone +conventional treatment p rocess +O₃ +BAC and Process Ⅱ-p re-ozone + conventional treatment p rocess +BAC were adop ted to perform a contrast test. The experimental results were finally compared with the practical data of the Nanzhou Drinking-Water Treatment Plant. Some suggestions for the optimization of O₃-BAC process were made in accordance with the quality of the raw water. The results of the p ilot2scale experiment show that, in order to ensure the drinking-water quality, Process Ⅱ should be adop ted when the raw water is of a COD_Mn of no more than 3. 0mg/L and a NH₃-N content of no more than 1. 0mg/L, and that ProcessⅠshould be adopted when the raw wa-ter is of a COD_Mn ofmore than 3. 5mg/L or a NH₃-N content ofmore than 1. 5mg/L. The p ractical operation results of the Nanzhou Drinking2Water Treatment Plant also reveal that Processes Ⅰand Ⅱ can be alternately adop ted in accordance with the quality of the raw water.

Key words: raw water, water quality, ozone, biological activated carbon, advanced treatment, operation optimiza