Investigation on the Hydrodynamic Behaviors of the Clarifier with an Interior Baffle in WWTP by using of Radiotracer $^{99m}Tc$

$^{99m}Tc$ 추적자를 이용한 하수처리 시설 내 침전조의 정류벽 설치 유무에 따른 유체거동 변화측정

  • Kim, Jin-Seop (Korea Atomic Energy Research Institute, Radioisotope Research & Development Center) ;
  • Kim, Jong-Bum (Korea Atomic Energy Research Institute, Radioisotope Research & Development Center) ;
  • Kim, Jae-Ho (Korea Atomic Energy Research Institute, Radioisotope Research & Development Center) ;
  • Jung, Sung-Hee (Korea Atomic Energy Research Institute, Radioisotope Research & Development Center)
  • 김진섭 (한국원자력연구원, 동위원소이용연구센타) ;
  • 김종범 (한국원자력연구원, 동위원소이용연구센타) ;
  • 김재호 (한국원자력연구원, 동위원소이용연구센타) ;
  • 정성희 (한국원자력연구원, 동위원소이용연구센타)
  • Published : 2007.09.30


The hydrodynamic behaviors of the clarifier with an interior baffle in a wastewater treatment plant was investigated by using a radiotracer $^{99m}Tc$(30 40 mCi) to verify the results of CFD(computational fluid dynamics) modelling in the previous study. The clarifier model was manufactured with consideration to the hydraulic similarity(1/21) of a real plant($L{\times}W{\times}H:2.6{\times}0.4{\times}0.2m$). By installation of an interior baffle to the clarifier, the strong density current at the bottom of the clarifier decreased substantially and increased the area of sludge settling zone, which were visualized successfully from the radiotracer experiment. Also the portion of short circuit stream changed from 48 % to 32 % and the mean residence time of sludge decreased from 940 sec to 810 sec, which corresponds to the results of CFD modelling. As a result, it is anticipated that radiotracer technology can be used as an important tool for designing new wastewater treatment plants and verifying their performances after structural modifications.


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