Journal of Korean Society of Water and Wastewater (상하수도학회지)

The Korean Society of Water and Wastewater (대한상하수도학회)
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Characteristic Features and Effect of Neo-Hydrofoil Impeller Applied in Sewage Treatment Plants

하수처리 공법별 네오하이드로포일 교반기의 적용 특성 및 효과

  • Joo, Yoon-Sik (Technology R&D Center, Woojin Co., Ltd.) ;
  • Son, Guntae (Department of Environmental Engineering, Kumoh National Institute of Technology) ;
  • Bae, Youngjun (Technology R&D Center, Woojin Co., Ltd.) ;
  • Lee, Seunghwan (Department of Environmental Engineering, Kumoh National Institute of Technology)
  • 주윤식 (주식회사 우진 기술연구소) ;
  • 손건태 (금오공과대학교 환경공학과) ;
  • 배영준 (주식회사 우진 기술연구소) ;
  • 이승환 (금오공과대학교 환경공학과)
  • Received : 2016.02.01
  • Accepted : 2016.03.31
  • Published : 2016.04.15
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Abstract

In this study, a newly developed agitator with hydrofoil impeller applied to actual biological process in advanced wastewater treatment plant was evaluated. Several series of experiments were conducted in two different wastewater treatment plants where actual problems have been occurred such as the production of scums and sludge settling. For more effective evaluation, computational fluid dynamics (CFD) and measurements of MLSS (Mixed Liquor Suspended Solids) and DO (Dissolved Oxygen) were used with other measuring equipments. After the installation of one unit of vertical hydrofoil agitator in plant A, scum and sludge settling problems were solved and more than seventy percent of operational energy was saved. In case of plant B, there were three cells of each anoxic and anaerobic tanks, and each cell had one unit of submersible horizontal agitator. After the integration of three cells to one cell in each tank, and installation of one vertical hydrofoil agitator per tank, all the problems caused by improper mixing were solved and more than eighty percent of operational energy was found to be saved. Simple change of agitator applied to biological process in wastewater treatment plant was proved to be essential to eliminate scum and sludge settling problems and to save input energy.

Keywords

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