Resources Recycling (자원리싸이클링)

The Korean Institute of Resources Recycling (한국자원리싸이클링학회)
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Classification of Metal Scraps Using Laser Induced Breakdown Spectroscopy

레이저유도붕괴분광법을 이용한 폐금속 분류

  • Shin, Sungho (School of Mechanical Engineering, Gwangju Institute of Science and Technology) ;
  • Lee, Jaepil (School of Mechanical Engineering, Gwangju Institute of Science and Technology) ;
  • Moon, Youngmin (School of Mechanical Engineering, Gwangju Institute of Science and Technology) ;
  • Choi, Jang-Hee (School of Mechanical Engineering, Gwangju Institute of Science and Technology) ;
  • Jeong, Sungho (School of Mechanical Engineering, Gwangju Institute of Science and Technology)
  • 신성호 (광주과학기술원 기계공학부) ;
  • 이재필 (광주과학기술원 기계공학부) ;
  • 문영민 (광주과학기술원 기계공학부) ;
  • 최장희 (광주과학기술원 기계공학부) ;
  • 정성호 (광주과학기술원 기계공학부)
  • Received : 2017.11.14
  • Accepted : 2017.12.18
  • Published : 2018.02.28
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Abstract

To enhance the recycling rate of used metal resources, it is strongly desired to develop a metal sorting system that can automatically identify metal type from mixed metal scraps and sort them separately. Laser-induced breakdown spectroscopy(LIBS) is a technique that enables real time classification of different metals based on multi-elemental and in-air analysis. In this work, we report the results of LIBS elemental analysis of field scrap samples acquired from a recycling company. By applying multivariate analysis, it was found that the LIBS signals of five different metals could be perfectly classified if surface contamination was removed. The classification accuracy degraded for LIBS signals including contaminant emission, which however could be overcome by performing the multivariate analysis using properly selected emission lines of higher correlation only. The significant improvement in classification accuracy and process speed by the selection of proper emission lines demonstrated the feasibility of LIBS technique as an industrial tool for metal scrap sorting.

폐금속자원의 재활용률을 높이기 위해서는 섞여 있는 다양한 종류의 금속 스크랩을 자동으로 선별할 수 있는 금속 선별 시스템 개발이 요구된다. 레이저유도붕괴분광법(Laser induced breakdown spectroscpoy, LIBS)은 빠른 속도로 공기 중에서도 다원소 분석이 가능하여 실시간 선별이 가능한 측면에서 매우 우수한 기술로 여겨지고 있으며, 측정된 LIBS 데이터의 다변량 통계분석을 통해 분류 정확도를 크게 향상시킬 수 있다. 본 연구에서는 재활용 업체로부터 획득한 5종류의 현장 폐금속 시료의 LIBS 성분 분석을 진행하였다. 금속 종류별로 좀 더 정확한 선별을 위해 적합한 분광선의 선정을 토대로 다변량 통계분석법이 적용되었으며, 선정된 분광선들을 이용하여 높은 정확도와 속도로 분류가 가능한 것을 확인할 수 있었다. 본 연구를 토대로 LIBS 기술의 산업현장에서의 실시간 폐금속 선별 적용 가능성을 제시한다.

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References

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