In this study, carbon dioxide (CO2) was used as an inhibitor of scale production on the surface of RO membrane. In order to compare the effects of CO2 injection on scale production, four RO modules: 1) without CO2 injection and anti-scalant (RO module #1), 2) with only CO2 injection (RO module #2), 3) with only anti-scalant (RO module #3), 4) with both CO2 injection and anti-scalant (RO module #4), were operated for 60 days under constant flux mode. The trans-membrane pressure (TMP) was observed to decrease significantly in RO modules with CO2 injection as compared with the other RO modules. When the feed water pH was controlled at 5.0 by injecting CO2, the maximum TMP in RO modules #2 and #4 was founded to decrease by 42 aㅋnd 40%, respectively. Moreover, the Ca2+ concentration in the concentrate was 20mg/L lower in RO modules without CO2 injection which is attributed to the scale formation on the surface of the RO membranes. The SEM-EDS analysis further showed a serious fouled RO membrane surface in RO modules #1 and #3.

1. 서 론
 2. 실험재료 및 방법
  2.1 MBR-RO 시스템 구성 및 운전 조건
  2.2 LSI (Langelier Saturation Index)
  2.4 기타분석방법
 3. 결과 및 고찰
  3.1 CO2 주입이 막간차압 및 LSI에 미치는 영향
  3.2 pH 연동제어를 통한 CO2 주입이 RO 모듈 막간차압에 미치는 영향
  3.3 RO 막 표면 형상 및 성상
 4. 결 론
 References

• 표민수(대구대학교 환경공학과) | Pyo Minsu
• 최영균(대구대학교 환경공학과) | Choi Younggyun Corresponding author