Abstract
A demonstration plant was carried out to investigate the removal efficiency of $NH_3-N$ and $KMnO_4$ consumption depending on the existence of pre-chlorination for the ozonation and activated carbon process in the S water treatment plant which is located at the middle of Keum River. The averge removal efficiency of $KMnO_4$ consumption for $O_3/GAC$ processes with pre-chlorination and $O_3/BAC$ processes without pre-chlorination were 48.6% and 50% respectively. It is similar to removal effect of $KMnO_4$ consumption for GAC and BAC process depending on the existence of pre-chlorination. Otherwise, the removal of THMFP for GAC and BAC process was 58% and 68% respectively. $NH_3-N$ was not almost removed by sand filter and ozonation, but the average removal efficiency in the BAC process was about 31%. Especially, $NH_3-N$ was not almost removed by $O_3/BAC$ processes at the low temperature (below $$10^{\circ}C$$) in the winter season, $O_3/BAC$ processes have the advantage of removal of organic substance when it is compared to pre -chlorination followed by $O_3/GAC$ processes. Pre-chlorination followed by $O_3/GAC$ processes were required to remove $NH_3-N$ in the winter season because the removal of $NH_3-N$ was almost ineffective by $O_3/BAC$ process.