Resources Recycling (자원리싸이클링)

The Korean Institute of Resources Recycling (한국자원리싸이클링학회)
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Physical Property Changes of Wasted Printed Circuit Board by Heat Treatment

열처리에 의한 폐 인쇄회로기판의 물성변화

  • Kim, Boram (Department of Earth Resources and Environmental Engineering, Hanyang University) ;
  • Park, Seungsoo (Department of Earth Resources and Environmental Engineering, Hanyang University) ;
  • Kim, Byeongwoo (Department of Earth Resources and Environmental Engineering, Hanyang University) ;
  • Park, Jaikoo (Department of Earth Resources and Environmental Engineering, Hanyang University)
  • 김보람 (한양대학교 자원환경공학과) ;
  • 박승수 (한양대학교 자원환경공학과) ;
  • 김병우 (한양대학교 자원환경공학과) ;
  • 박재구 (한양대학교 자원환경공학과)
  • Received : 2017.12.27
  • Accepted : 2018.01.19
  • Published : 2018.02.28
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Abstract

Physical property changes of printed circuit board (PCB) according to heat treatment conditions were investigated. The heat treatment was carried out in air and nitrogen atmosphere at temperature range from $200^{\circ}C$ to $325^{\circ}C$. Thermogravimetric analysis showed that the PCB was pyrolyzed in two steps. The thickness of PCB expanded by 11~28% at about $300^{\circ}C$ in both air and nitrogen atmosphere as layer disintegration occurred. Mechanical strength of PCB decreased from 338.4 MPa to 20.3~40.2 MPa due to the delamination caused by the heat treatment. The heated printed circuit boards were crushed and sieved for analysis of density distribution and liberation degree of copper according to particle size. As a result of the density distribution measurement, non metallic particles and copper particles were concentrated into different size range, respectively. The liberation degree of copper was improved from 9.3% to 100% at size range of $1,400{\sim}2,000{\mu}m$ by heat treatment.

열처리 조건에 따른 폐 인쇄회로기판의 물성 변화에 대해 조사하였다. 열처리는 $200^{\circ}C$부터 $325^{\circ}C$까지 공기 및 질소분위기에서 시행하였다. 열중량 분석 결과 인쇄회로기판은 두 단계로 열분해되었으며, 공기 분위기와 질소 분위기 공히 $300^{\circ}C$ 전후에서 층분리로 인해 인쇄회로기판의 두께가 11~28% 팽창되었다. 기계적 강도는 열처리 유 무에 따라 338.4 MPa에서 20.3~40.2 MPa까지 감소하였다. 열처리한 인쇄회로기판을 파쇄 후 체분리하여 입도에 따른 밀도 분포 및 단체분리도를 측정하였다. 밀도측정 결과, 비금속 입자와 구리 입자가 각각 다른 입도구간에 집중되었다. 구리의 단체분리도는 열처리를 함으로써 $1,400{\sim}2,000{\mu}m$ 구간에서 9.3%에서 100%로 향상되었다.

Keywords

References

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