Journal of the Korean Recycled Construction Resources Institute (한국건설순환자원학회논문집)

Korean Recycled Construction Resources Institute (한국건설순환자원학회)
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The Effect of Electrochemical Treatment in Lowering Alkali Leaching from Cement Paste to an Aquatic Environment: Part 1- Leachability of Alkali Ions

전기화학적 기법을 통한 시멘트페이스트의 수중노출에 따른 알칼리이온 침출저감 효과: Part 1- 알칼리이온의 침출능

  • Bum-Hee Youn (Department of Civil & Environment Engineering, Hanyang University) ;
  • Ki-Yong Ann (Department of Civil & Environment Engineering, Hanyang University)
  • 윤범희 (한양대학교 건설환경공학과) ;
  • 안기용 (한양대학교 건설환경공학과)
  • Received : 2023.04.25
  • Accepted : 2023.05.15
  • Published : 2023.06.30
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Abstract

In this study, the effect of electrochemical treatment in mitigating alkali leaching into an aquatic environment was investigated. To modify the surface of cement paste, 1000 mA/m2 of the direct current was passed through anodic graphite to the external mesh for 4 weeks. Then, the cement paste specimen was exposed to still water in air-tight condition to prevent natural healing of alkali leaching in the water. For 100 days of monitoring in water, the pH value was marginally increased at the electrochemical treatment, while control specimen ranked to the even higher pH accounting for 13.2 in the pH. Moreover, after the pH monitoring, the pH profile for the paste specimen indicated that the electrochemical treatment was effective in securing the higher alkalinity of cement matrix. The water obtained from alkali leaching process, was used to ecological test for Daphnia magna. It was evident that the electrochemical treatment had minimal adverse effect on ecological impact, while control specimen mostly immobilized the standard Daphnia magna.

본 연구에서는 알칼리 침출수의 수서환경 완화를 위한 전기화학적 처리에 대한 효과를 평가하였다. 시멘트 페이스트의 표면을 개질하기 위해 1,000 mA/m2 의 직류를 양극 graphite를 통해 외부 메쉬로 4주 동안 통전한 후, 물 속의 알칼리 침출이 자연적으로 치유되는 것을 방지하기 위해 시멘트 페이스트 시편을 밀폐된 상태의 정지된 물에 침지시켰다. 물 속에서 100일간의 모니터링 한 결과, 전기화학적 처리를 한 시편의 pH 값은 약간 증가한 반면, control 시편의 pH의 경우 13.2를 나타내어 훨씬 더 높은 pH값을 나타내었다. 또한, pH 모니터링 이후 시멘트 페이스트 시료에 대한 pH 프로파일은 전기화학적 처리가 시멘트 매트릭스의 높은 알칼리도 확보에 효과적임을 알 수 있었다. 알칼리 침출 공정에서 얻은 알칼리침출수는 다프니아 마그나의 생태학적 테스트에 사용되었다. Control 시편은 표준 Daphnia Magna를 대부분 고정시킨 반면, 전기화학적 처리기법의 경우 생태학적으로 매우 우수하다는 것을 확인하였다.

Keywords

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