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Establishment of Tailing Disposal Scenario in Open-Pit and Surface Pillar Stability Analysis

노천채굴적 내 광미 적치 시나리오 구축 및 천반 수평필러 안정성 분석

  • Il-Seok Kang (Department of Energy Systems Engineering, Seoul National University) ;
  • Jae-Joon Song (Department of Energy Systems Engineering, Seoul National University) ;
  • Thomas Pabst (Department of Civil, Geological and Mining Engineering, Polytechnique Montreal)
  • 강일석 (서울대학교 에너지시스템공학부) ;
  • 송재준 (서울대학교 에너지시스템공학부) ;
  • Received : 2023.12.08
  • Accepted : 2023.12.27
  • Published : 2024.02.29

Abstract

Utilization of completed open-pit for mining waste disposal is an alternative method of tailing storage facility (TSF), which can minimize the area and cost required for the installation of TSF. However, long-term tailing disposal into open-pit has a potential risk of reducing mechanical stability of surrounding rock mass by acting as an additional load. In this research, a realistic open-pit tailing disposal scenario of 60,400 hours was established based on the case of Marymia gold mine, Australia. Mechanical stability of surface pillar between open-pit and underground stope was analyzed numerically by using Sigma/W, under different stope geometry and rock mass conditions. Simulation results showed that long-term tailing disposal into open-pit can significantly increase the failure probability of surface piller. This result suggests that mechanical stability of mine geometry should be conducted beforehand of open-pit tailing disposal.

생산이 완료된 노천광산 채굴적을 광미(광물찌꺼기) 적치 장소로 활용하는 방안은 기존 광미 적치 시설(TSF, Tailing storage facility)의 설치 공간 및 운영비용 문제 해결을 위한 대안으로 제시된다. 하지만 장기간에 걸쳐 적치된 광미는 주변 암반에 추가적인 하중으로 작용하여 광산의 역학적 안정성을 저해할 위험성이 존재한다. 본 연구에서는 호주 Marymia 광산의 사례를 참고하여 약 60,400 시간에 걸친 광미 적치 시나리오를 구축하였으며, 다양한 지하 채광장 형태 및 암반 조건에 따른 천반 수평필러의 역학적 안정성을 Sigma/W 해석 소프트웨어를 활용하여 분석하였다. 분석 결과, 광미 적치가 장기간 지속됨에 따라 천반 수평필러의 파괴 가능성이 유의미하게 증가함을 확인하였다. 해당 결과는 노천채굴적 내 광미 적치 시 광산 구조에 대한 역학적 안정성 고려가 필수적임을 시사한다.

Keywords

Acknowledgement

본 연구는 2023년도 정부(산업통상자원부)의 재원으로 해외자원개발협회의 지원(2021060003, 스마트 마이닝 전문 인력 양성)과 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원(No. 2022R1F1A1076409)을 받아 수행된 연구입니다. 또한 본 연구는 폴리테크니크 몬트리올- 캐나다 광업환경연구소(RIME)의 국제 인턴쉽 프로그램(International Internship Program)의 지원을 받아 수행되었습니다.

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