호기성 그래뉼 슬러지를 이용한 연속 회분식 하수고도처리 공정의 Pilot Plant 운전특성

본 연구에서는 호기성 그래뉼 슬러지가 적용된 연속 회분식 하수고도처리 공정(AGS-SBR)의 운전 특성을 평가하고자 처리용량 225 m 3 /day의 Pilot plant를 경기도 S시 하수처리장에 설치하여 운영하였다. Pilot plant 운전기간 동안 F/M비(CODMn Kg/MLVSS Kg)는 0.02~0.24 범위였으며, BOD5, CODMn, SS, T-N, T-P의 제거효율은 각각 98.2%, 89.5%, 93.6%, 64.6%, 93.5%로 나타났다. 하수 수온이 11℃ 이하로 유입된 동절기에 질소제거효율이 저하되지 않았으나, MLVSS 농도 2,000 mg/L 이하, C/N비 2 이하에서 처리효율이 저하되는 경향을 보였다. 운전기간이 경과하면서 호기성 그래뉼 슬러지가 조밀해지고 커지는 것이 관측되었으며 폭기조내 MLSS중 AGS 비율이 증가하고 SVI가 향상되었다. AGS의 미생물군집 분석 결과, 유기물 산화 미생물을 비롯하여 질산화 및 탈질에 관여하는 미생물이 다량 존재하는 것으로 확인되었다. 또한, 처리용량1,000 m 3 /day 이하의 국내 SBR 계열 하수처리장과 비교시, 연간 슬러지 처리비용은 54.9%, 전력소비량은 34.7% 절감된 것으로 나타났다. In this study, a pilot plant with a capacity of 225 m 3 /d was installed and operated at the S sewage treatment plant in Gyeonggi-do to assess the operational characteristics of the Aerobic Granualr Sludge - Sequencing Batch Reactor (AGS-SBR) Process. During the pilot plant operation, F/M ratio was in the range of 0.02 to 0.24 (CODMn Kg/MLVSS Kg) and the average removal efficiency of BOD5, CODMn, SS, T-N and T-P was 98.2%, 89.5%, 93.6%, 64.6%, and 93.5%, respectively. In winter, nitrogen was reliably removed at influent sewage temperatures below 11°C, but treatment efficiency tended to decrease at MLVSS concentrations below 2,000 mg/L and below C/N ratio 2. As operating period elapsed, it was observed that AGS was getting bigger and SVI was improved. As a result of microbial community analysis, it was confirmed that nitrification and denitrification microorganisms exist as well as heterotrophic microorganisms. The AGS-SBR operation results showed that the annual sludge disposal cost was reduced by 54.9% and the power consumption was reduced by 34.7% compared to the domestic SBR type sewage treatment plant with a processing capacity of 1,000 m 3 /day or less. KCI Citation Count: 3