In Korea, many drinking water treatment plants (DWTPs) have introduced and are going to introduce biological activated carbon (BAC) process to treated dissolved organic matter (DOM) in water which are difficult to control by conventional water treatment processes. Even though more decade have passed since introduced BAC in Korea, most of BAC operating method was followed to the modified sand filter operating manuals. In case of BAC backwashing, many DWTPs set the periods of backwashing about 3∼5 days.
In this study, we have collected data to set the proper BAC backwashing periods from both pilot-plant and real DWTPs. We had measured heterotrophic plate count (HPC), turbidity, water temperature, dissolved organic carbon (DOC) and headloss from just after backwashing to the next backwashing time for two years. Considering water quality factors, the BAC run time from backwashing to the next backwashing could extend more 30 days without water quality deterioration if the head loss do not reach the limited level which depends on each BAC facilities’ condition. It means the BAC treated water could be saved in the proportion of extended the backwashing period to the existing backwashing period.

Abstract
 1. 서론
 2. 실험재료 및 방법
  2.1. Pilot-plant BAC 여과지 운전 조건
  2.2. 실 plant BAC 여과지 운전 조건
  2.3. 분석항목 및 방법
 3. 실험결과 및 고찰
  3.1. Pilot-plant에서의 BAC 여과지 역세척 평가
  3.2. 실 plant에서의 BAC 여과지 역세척 평가
  3.3. 경제성 평가
 4. 결 론
 REFERENCES

• 김상구(부산광역시 상수도사업본부 수질연구소) | Sang-Goo Kim (Water Quality Institute, Busan Water Authority)
• 박홍기(부산광역시 상수도사업본부 수질연구소) | Hong-Gi Park (Water Quality Institute, Busan Water Authority)
• 손희종(부산광역시 상수도사업본부 수질연구소) | Hee-Jong Son (Water Quality Institute, Busan Water Authority) Corresponding author
• 염훈식(부산광역시 상수도사업본부 수질연구소) | Hoon-Sik Yoom (Water Quality Institute, Busan Water Authority)
• 류동춘(부산광역시 상수도사업본부 수질연구소) | Dong-Choon Ryu (Water Quality Institute, Busan Water Authority)