A Study on Acid Recovering Process by Neutralization and Water-Splitting Electrodialysis (WSED)

중화법과 전기투석에 의한 산회수 공정연구

  • Lee, Hong Joo (Department of Environmental Science and Engineering Kwangju Institute of Science and Technology(K-JIST)) ;
  • Moon, Seung-Hyeon (Department of Environmental Science and Engineering Kwangju Institute of Science and Technology(K-JIST)) ;
  • Park, Sung-Kook (Environmental and Energy Research Division Research Institute of Industrial Science and Technology(RIST)) ;
  • Chun, Hee-Dong (Environmental and Energy Research Division Research Institute of Industrial Science and Technology(RIST))
  • 이홍주 (광주과학기술원 환경공학과) ;
  • 문승현 (광주과학기술원 환경공학과) ;
  • 박성국 (포항산업과학연구원 수질환경연구팀) ;
  • 전희동 (포항산업과학연구원 수질환경연구팀)
  • Published : 1997.12.01

Abstract

Recently the treatment of industrial wastes by membrane processes has drawn much attention due to increasing demands for clean technology. In the process investigated in this study, metal species in the acidic wastes are precipitated as metal hydroxide forms in a neutralization tank, and acid and base solutions are regenerated by water-splitting electrodialysis(WSED) to be reused in the process. Material balances of the processes for treating pickle liquor and mixed wastewater were calculated to explain conceptual design of the process. Experiments for neutralization precipitation with KOH and NaOH for mixed wastewater were carried out to precipitate metal hydroxide and to recover salt solution as supernatant. Also WSED of the salt solutions producing acid and base was tested in 2 or 3 compartment stacks using KCl and NaCl to investigate the effects of stack configurations on the WSED performance.

최근 청정기술의 필요성이 증가하면서 막분리 공정에 의한 산업폐수 처리기술에 대한 관심이 높아가고 있다. 이 연구는 중화법과 water-splitting electrodialysis (WSED)를 이용하여 금속을 포함하고 있는 폐수에서 유용한 물질을 회수하고 무방류계를 실현하기 위한 것이다. 본 연구에서는 산폐수와 혼합폐수 처리의 공정 설계를 위한 공정의 흐름를 확립하였고, 이 공정에 따른 물질수지를 계산하였다. 또한 주요 단위공정인 침전조와 산회수공정의 운전인자에 대한 실험을 수행하였다. 침전공정에서는 KOH와 NaOH를 중화제로 이용하여 pH에 따른 침전효율과 슬러지양을 비교하였으며 산회수 공정에서는 KCl과 NaCl을 합성원료로 이용하여 WSED의 막구조에 따른 회수효율을 조사하였다.

Keywords