Resources Recycling (자원리싸이클링)

The Korean Institute of Resources Recycling (한국자원리싸이클링학회)
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Distribution and Evaluation of Rare Earth Elements contained in Coal Ashes from Korea Circulating Fluidized Bed Combustion (CFBC)

국내 순환유동층보일러 석탄재의 희토류 분포 특성 및 평가

  • Kim, Young-Jin (Department of Research and Development, Korea Institute of Limestone and Advanced Materials) ;
  • Baek, Chul-Seoung (Department of Research and Development, Korea Institute of Limestone and Advanced Materials) ;
  • Seo, Jun-Hyung (Department of Research and Development, Korea Institute of Limestone and Advanced Materials) ;
  • Choi, Moon-Kwan (Department of Research and Development, Korea Institute of Limestone and Advanced Materials) ;
  • Cho, Kye-Hong (Department of Research and Development, Korea Institute of Limestone and Advanced Materials) ;
  • Ahn, Ji-Whan (Center for Carbon Mineralization, Korea Institute of Geoscience and Mineral Resources)
  • 김영진 (한국석회석신소재연구소 연구개발실) ;
  • 백철승 (한국석회석신소재연구소 연구개발실) ;
  • 서준형 (한국석회석신소재연구소 연구개발실) ;
  • 최문관 (한국석회석신소재연구소 연구개발실) ;
  • 조계홍 (한국석회석신소재연구소 연구개발실) ;
  • 안지환 (한국지질자원연구원 탄소광물화적정기술사업단)
  • Received : 2018.07.06
  • Accepted : 2018.10.25
  • Published : 2018.12.28
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Abstract

The rare earth elements (REE) contents in coal ashes generated from domestic circulating fluidized bed combustion (CFBC) were identified for evaluating the exploitation possibilities for recovering rare earth elements. Total REE contents for all of the samples in this study ranged from 82.2 ~ 311.7 ppm, much lower than the 403.5 ppm given on the average value of world coal ash. As a result of analysis using REE concentration and Outlook coefficient, six types of coal ashes falls in the unpromising area (I). These results suggest that it is difficult to recover rare earth element from coal ashes at this stage. It has been confirmed that to recover rare earth elements in coal ashes, research on the pretreatment and concentration process for critical REE is requirement.

국내 순환유동층보일러(CFBC)발전소로부터 발생된 석탄재의 희토류 성분, 함량 및 분포특성을 평가하여 희토류 회수 개발 가능성을 검토하였다. 국내 CFBC발전소에서 확보한 6 종 석탄재의 희토류 함량은 82.2 ~ 311.7 ppm으로, 세계 석탄재 희토류 평균값으로 제시된 403.5 ppm에 비해 낮게 확인되었다. 희토류 농도와 Outlook coefficient값을 이용한 분석 결과, 6 종의 석탄재 모두 unpromising area (I)로 분류되었다. 현재 단계에서 석탄재의 희토류 회수를 위한 개발은 어려운 상태임을 확인하였고, 향후 석탄재 중 희토류 성분의 회수를 위해서는 critical 희토류를 주요 대상으로, 이를 농축하기 위한 전처리 및 선별 공정 개발이 필요한 것으로 확인되었다.

Keywords

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Fig. 1. REE distribution in coal ashes. ((a) domestic, (b)overseas)7-10,16).

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Fig. 2. XRD patterns of coal ashes from Korea CFBC plants.

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Fig. 3. REE distribution in coal ashes from Korea CFBC plants.

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Fig. 4. Classification of REE in coal ashes from Korea CFBC plants.

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Fig. 5. Evaluation of REE in coal ashes from Korea CFBC plants.

Table 1. Samples name of coal ashes used in this study

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Table 2. The result of the XRF analysis for coal ashes from Korea CFBC plants

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