Effect of residual metal salt on reverse osmosis membrane by coagulation-UF pretreatment process

응집-UF 전처리 공정에 의한 잔류 금속염이 역삼투막에 미치는 영향

  • Go, Gilhyun (Department of Environmental Engineering, Pukyong National University) ;
  • Kim, Suhyun (Department of Environmental Engineering, Pukyong National University) ;
  • Kang, Limseok (Department of Environmental Engineering, Pukyong National University)
  • 고길현 (부경대학교 환경공학과) ;
  • 김수현 (부경대학교 환경공학과) ;
  • 강임석 (부경대학교 환경공학과)
  • Received : 2019.06.21
  • Accepted : 2019.08.30
  • Published : 2019.12.17


Pretreatment system of desalination process using seawater reverse osmosis(SWRO) membrane is the most critical step in order to prevent membrane fouling. One of the methods is coagulation-UF membrane process. Coagulation-UF membrane systems have been shown to be very efficient in removing turbidity and non-soluble and colloidal organics contained in the source water for SWRO pretreatment. Ferric salt coagulants are commonly applied in coagulation-UF process for pretreatment of SWRO process. But aluminum salts have not been applied in coagulation-UF pretreatment of SWRO process due to the SWRO membrane fouling by residual aluminum. This study was carried out to see the effect of residual matal salt on SWRO membrane followed by coagulation-UF pretreatment process. Experimental results showed that increased residual aluminum salts by coagulation-UF pretreatment process by using alum lead to the decreased SWRO membrane salt rejection and flux. As the salt rejection and flux of SWRO membrane decreased, the concentration of silica and residual aluminum decreased. However, when adjusting coagulation pH for coagulation-UF pretreatment process, the residual aluminum salt concentration was decreased and SWRO membrane flux was increased.



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