In the study, we investigated the behavior and removal efficiency of organics, nitrogen, phosphorus with operating conditions in SBRs. Substrate used was synthetic wastewater in which the ratio of COD_cr : N : P was 100 : 12 : 2. The cycling time in SBRs was adjusted at 6 hours and 8 hours, and then certainly included anaerobic and aerobic conditions. Also, for each cycling time, we performed 2 series of experiment simultaneously which was set up 10 days and 20 days as SRT. The removal efficiency of COD_cr, was over 97% in all operating conditions. In the 6 hours cycling time, the removal efficiency of PO_4^3- -P reached almost 100% in steady state. And then we could observe a typical phenomena of phosphorus release and uptake, and the removal efficiency of N was 67%. Residual N source was almost TKN and most of the rest remained as NO_2^- -N. Also the difference in both SRTs was not observed practically. In the 8 hours cycling time, dissolution of sludge appeared. and, PO_4^3- -P was not nearly removed but nitrogen was removed up to 75%. And the residual nitrogen was accumulated as NO_2^- -N.

• 한기백(경주전문대학 환경공업과) | Gee-Baek Han (Dept. of Environ, Eng., Kyongju Junior College)
• 박동근(동서공과대학 환경공학과) | Dong-Keun Park (Dept. of Environ. Eng., Dongseo University)
• 이해군(부산대학교 환경공학과) | Hae-Goon Lee (Dept. of Environ. Eng., Pusan National University)
• 김창원(부산대학교 환경공학과) | Chang-Won Kim (Dept. of Environ. Eng., Pusan National University)