The clogging phenomenon in the fixed film reactor is shown when biomass growth is excessive for long operating time. In addition, effluent water quality gets worse because of detachment of biomass. In this study, we conducted air - backwashing to sustain biomass in reactor to complement these defects. The results of experimental are showed in the following conclusion.
The detachment rate was 19.5 - 38.0 % when the organic loading rate was 0.40 - 1.32 ㎏ COD/㎥/day, the air - backwashing intensity was 2 L/min(6.7 ㎥/㎡/hr) and the backwashing time was 15 - 19 seconds.
And the detachment rate was 32.2 - 58.6 % when the organic loading rate was 1.37 - 2.27 ㎏ COD/㎥/day, the backwashing time was 1 - 12 minutes. As organic loading rate and backwashing time are increased, detachment of fixed biomass is increased. The detachment equation with detachment rate(DR, %), backwashing time(BWT, min), fixed biomass concentration(FB, ㎎/L), and organic loading rate(OLR, ㎏ COD/㎥/day) through multiple linear regression was given by the following equation:
DR = 17.964 BWT^0.41407 FB^0.0597 OLR^0.1945

• 이창근(창원정밑) | Chang-Geun Lee (Chang Won Precision Co. Ltd.)
• 김정숙(부경대학교 해양산업개발연구소) | Jeong-Sook Kim (Engineering Reserch Center, Pukyong National University)
• 강임석(부경대학교 환경공학과) | Im-Suk Kang (Department of Environmental Engineering, Pukyong National University)
• 이병헌(부경대학교 환경공학과) | Byung-Hun Lee (Department of Environmental Engineering, Pukyong National University)