Fluctuation in the Flow of Poly Aromatic Hydrocarbons (PAHs) into the Aquatic Environment through the City Sewage Treatment Process

Abstract

The following three conclusions were reached, as a result of this study on the fluctuation in the amount of poly aromatic hydrocarbons (PAHs) flowing into the aquatic environment through the sewage treatment center in urban area. 1) More than 98 % of the PAHs found in influent water were eliminated from the water during the treatment process on fair weather days. 2) Due to primary treatment of influent water on rainy weather days, 20∼30 % of the incoming PAHs were discharged to nearby public water environment. This situation seems to require administrative improvement by the local government in the near future. 3) After centrifugal separation, most of the PAHs transferred to sludge were eliminated by incineration at high temperature over 850 degree C. Only a small amount of the PAHs, remaining in the ash, was buried in a dump yard.