In the case of treating a source water containing higher concentrations of Fe2+, Mn2+ and organic pollutants, the Fe2+ was partially removed by pretreatment steps of aeration-sand filtration, while Mn2+ and organics were removed mainly by an ozonation-BAC process. The performance of the advanced treatment plant and removal mechanisms are studied in this paper. The optimal O3 dosage and residual O3 were found to be 4 mg l−1 and 0.4 mg l−1, respectively, for which the Fe2+, Mn2+ and CODMn removals reached 98%, 95% and 85.5% respectively.
GC/MS analytical results showed that the advanced water treatment plant was very efficient in micro-organic pollutant removal. The total species decreased from 59 in the raw water to 50, 40 and 26 in the effluents of the sand filter, ozonation column and BAC filter, respectively. The priority and potentially hazardous pollutant species decreased from 16 in the raw water to 10, 8 and 5 in the corresponding effluents, respectively.
- advanced treatment
- biological activated carbon
- organic pollutants
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