Journal of Korean Society on Water Environment (한국물환경학회지)

Korean Society on Water Environment (한국물환경학회)
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Evaluation of Pressurized Water Mixing of Big Pipe with CFD at Water Treatment Process

CFD를 활용한 수처리공정 대형관에서 압력수 혼합공정 평가

  • 조영만 (부산상수도사업본부 수질연구소) ;
  • 유현철 (부산상수도사업본부 수질연구소) ;
  • 장경혁 (부산상수도사업본부 수질연구소) ;
  • 정용준 (부산가톨릭대학교 환경공학과)
  • Received : 2021.01.04
  • Accepted : 2021.04.15
  • Published : 2021.05.30
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Abstract

Mixing is a very important unit in water treatment process. A mechanical stirring method is generally used for mixing, but recently, the use of pressurized water mixing method (pump diffusion flash mixer) has gained interest because it is more advantageous in terms of mixing time, noise, energy consumption, and maintenance. The following conclusions were obtained from the study of pressurized water mixing method by Computational Fluid Dynamics. Firstly, the mixing degree in the pipe increased as the density of water increased. Secondly, even if the relative velocity between flow rate in the pipe and the pressurized water was constant, the mixing degree decreased as the flow velocity in the pipe increased. Thirdly, the stronger the injection energy the higher the mixing degree. It was also found that the mixing degree was greatly affected by the injection velocity as compared to the injection flow amount. Finally, the required energy to achieve 95% mixing degree at the distance of 10 times diameter in big pipes of 500 mm to 3000 mm was 0.3 to 4.5 kJ. The result of this study could be used in the process design of injection with water purification chemicals, such as, ozone, chlorine, and coagulant.

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References

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