• Evaluation of Field Applicability of Calcium Polysulfide for Cadmium and Zinc Immobilization in Groundwater and Its Impact on Microbial Ecology

  • Sang Hun An1,2ㆍDong-Hun Kim1ㆍSung Pil Hyun1ㆍSoo Min Song1,2ㆍHee Sun Moon1,2*ㆍByung Yong Yoon3ㆍYong Hoon Cha3ㆍKyoungphile Nam4

  • 1Groundwater Environment Research Center, Climate Change Response Division, Korea Institute of Geoscienceand Mineral Resources (KIGAM)
    2Geological Science, University of Science and Technology (UST)
    3Geogreen21 Co., Ltd.
    4Department of Civil and Environmental Engineering, Seoul National University

  • 환원제를 이용한 지하수 내 고농도 카드뮴 및 아연 고정화 기술 현장 적용성 평가 및 미생물 생태 변화 모니터링

  • 안상훈1,2ㆍ김동훈1ㆍ현성필1ㆍ송수민1,2ㆍ문희선1,2*ㆍ윤병용3ㆍ차용훈3ㆍ남경필4

  • 1한국지질자원연구원 기후변화대응연구본부 지하수환경연구센터
    2과학기술연합대학원대학교 지질과학전공
    3(주)지오그린21
    4서울대학교 건설환경공학부

  • This article is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This study investigated the effectiveness of calcium polysulfide (CPS; CaSx) injection for the in-situ immobilization of cadmium and zinc-contaminated groundwater. The research focused on the impact of CPS injection on groundwater quality parameters, such as dissolved oxygen (DO), oxidation-reduction potential (ORP), and pH, as well as heavy metal precipitate formation and aquifer's microbial community dynamics on a field scale. The results demonstrated that the injected CPS formed a reactive zone, effectively reducing cadmium and zinc concentrations for a limited period. However, contaminant rebound occurred over time, necessitating repeated CPS injections. A single injection of CPS achieved a removal efficiency of 70~99%, lasting approximately 20 days. In contrast, repeated injections sustained the removal effects up to 37 days. Chemical analyses confirmed the precipitation of cadmium and zinc sulfide (CdS and ZnS), which remained stable in the aquifer even 86 days post-injection. Elemental sulfur (S) was detected in a significant quantity, contributing to the observed low DO levels. Microbial community exhibited a shift from an initial prevalence of sulfur-oxidizing and iron-oxidizing bacteria to a later dominance of sulfate-reducing bacteria following the cessation of high DO recycled water inflow, potentially enhancing the formation of CdS and ZnS.


Keywords: CPS (calcium polysulfide), Heavy metals, Microbial community, In-situ immobilizationon

This Article

  • 2024; 29(5): 14-26

    Published on Oct 31, 2024

  • 10.7857/JSGE.2024.29.5.014
  • Received on Sep 21, 2024
  • Revised on Sep 25, 2024
  • Accepted on Oct 10, 2024

Correspondence to

  • Hee Sun Moon

  • 1Groundwater Environment Research Center, Climate Change Response Division, Korea Institute of Geoscienceand Mineral Resources (KIGAM)
    2Geological Science, University of Science and Technology (UST)

  • E-mail: hmoon@kigam.re.kr