Effects of Recycled Washwater on Pollutant Removal and Particle Characteristics during Coagulation

회수수가 응집공정의 오염물질 제거 및 입자특성에 미치는 영향

  • 문병현 (창원대학교 환경공학과) ;
  • 김승현 (경남대학교 공간환경시스템공학부) ;
  • 박미선 (창원대학교 환경공학과) ;
  • 이향인 (창원대학교 환경공학과) ;
  • 이강춘 (동의대학교 환경공학과)
  • Published : 2002.09.01


The recycled washwater, which has different water quality and is produced about 5 to 20% of the total water volume treated, affects the unit operation of water treatment, especially coagulation process. However, the effects of recycled washwater on unit operation of water treatment have not been fully investigated. In this study, effects of recycled washwater on coagulation process were investigated to find the optimum coagulation condition by analyzing turbidity, $UV_{254}$, TOC removal efficiencies. In addition, effects of recycled washwater on residual Al after coagulation were studied by analyzing soluble and particulate Al. The size distribution and fractal dimension of coagulated also analyzed. The recycled washwater was lower pH than the raw water. And the recycled washwater had higher $UV_{254}$, TOC and residual Al concentration than the raw water. Residual Al concentration of recycled washwater was about 50 times higher than that of raw water. Optimum coagulant dosages on the blending recycled washwater and the raw water for turbidity, $UV_{254}$ and Al removal were lower than that on the raw water. However, TOC removal increased by increasing coagulant dosage. The size and fractal dimension of coagulated particle produced in the blending recycled washwater were larger, which imply faster settling velocity, than those produced in the raw water only.


Recycling Water;Coagulation;Turbidity;TOC;Al;Particle Size;Fractal dimension


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