• Optimal Injection Dosage Determination of Calcium polysulfide (CPS) for Remediation of Groundwater Contaminated with Complex Heavy Metals with Various Concentration Ranges

  • Jiwon Choi1 ㆍJin Chul Joo2*ㆍKyoungphile Nam3 ㆍHyeon Woo Go4 ㆍ Won Seok Park4 ㆍInwon Lee4 ㆍDong Jun Kim1

  • 1Department of Environmental Engineering, Hanbat National University, Daejeon 34158, Korea
    2Department of Civil and Environmental Engineering, Hanbat National University, Daejeon 34158, Korea
    3Department of Civil and Environmental Engineering, Seoul National University, Seoul 08826, Korea
    4Beautiful Environmental Construction Inc., Gyeonggi-do 13207, Korea

  • 다양한 농도의 복합 중금속으로 오염된 지하수 정화를 위한 Calcium polysulfide (CPS)의 최적 주입량 도출

  • 최지원1 ㆍ주진철2*ㆍ남경필3 ㆍ고현우4 ㆍ박원석4 ㆍ이인원4 ㆍ김동준1

  • 1국립한밭대학교 환경공학과
    2국립한밭대학교 건설환경공학과
    3서울대학교 건설환경공학부
    4아름다운환경건설(주)

  • 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 assessed the optimal injection dosage of calcium polysulfide (CPS) for the remediation of groundwater contaminated with cadmium (Cd) and zinc (Zn) at varying concentrations. CPS, a powerful reducing agent, was applied to groundwater samples from two contaminated sites with high and low heavy metal levels. Increasing CPS dosage resulted in higher pH and lower oxidation-reduction potential (ORP). In the high-concentration sample, a CPS dosage of 0.3% achieved over 99% removal of Cd and Zn, with CPS/heavy metal mass ratios of 2.29 for Cd and 3.13 for Zn. In the low-concentration sample, CPS dosages between 0.03% and 0.06% also achieved 99% removal but required higher mass ratios (15.88 for Cd and 5.33 for Zn). Surface analysis using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) confirmed the formation of metal sulfides such as CdS and ZnS. The findings suggest that lower metal concentrations necessitate higher CPS-to-metal ratios for effective remediation, underscoring the importance of site-specific optimization of CPS injection for stabilizing heavy metals in groundwater.


Keywords: Calcium polysulfide (CPS, CaSx), Complex heavy metals, Groundwater, Precipitation, Metal suilfides

This Article

  • 2024; 29(6): 49-59

    Published on Dec 31, 2024

  • 10.7857/JSGE.2024.29.6.049
  • Received on Oct 19, 2024
  • Revised on Nov 18, 2024
  • Accepted on Nov 22, 2024

Correspondence to

  • Jin Chul Joo

  • Department of Civil and Environmental Engineering, Hanbat National University, Daejeon 34158, Korea

  • E-mail: jincjoo@hanbat.ac.kr