Clean Technology (청정기술)

The Korean Society of Clean Technology (한국청정기술학회)
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Characteristics of Coal Devolatilization and Spontaneous Combustion at Low Temperatures

저온영역에서 석탄의 탈휘발 및 자연발화 특성 연구

  • Sung Min Yoon (Clean Fuel Laboratory, Korea Institute of Energy Research) ;
  • Seok Hyeong Lee (Clean Fuel Laboratory, Korea Institute of Energy Research) ;
  • Tae Hwi An (Department of Environmental Engineering, University of Seoul (UOS)) ;
  • Myung Won Seo (Department of Environmental Engineering, University of Seoul (UOS)) ;
  • Sang Won Lee (IGCC Power Plant Department, Korea Western Power) ;
  • Dae Sung Kim (IGCC Power Plant Department, Korea Western Power) ;
  • Tae-Young Mun (Clean Fuel Laboratory, Korea Institute of Energy Research) ;
  • Sung Jin Park (Clean Fuel Laboratory, Korea Institute of Energy Research) ;
  • Sang Jun Yoon (Clean Fuel Laboratory, Korea Institute of Energy Research) ;
  • Ji Hong Moon (Clean Fuel Laboratory, Korea Institute of Energy Research) ;
  • Jae Goo Lee (Clean Fuel Laboratory, Korea Institute of Energy Research) ;
  • Jong Hoon Joo (School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology) ;
  • Ho Won Ra (Clean Fuel Laboratory, Korea Institute of Energy Research)
  • 윤성민 (한국에너지기술연구원 청정연료연구실) ;
  • 이석형 (한국에너지기술연구원 청정연료연구실) ;
  • 안태휘 (서울시립대학교 환경공학부) ;
  • 서명원 (서울시립대학교 환경공학부) ;
  • 이상원 (한국서부발전 IGCC발전처) ;
  • 김대성 (한국서부발전 IGCC발전처) ;
  • 문태영 (한국에너지기술연구원 청정연료연구실) ;
  • 박성진 (한국에너지기술연구원 청정연료연구실) ;
  • 윤상준 (한국에너지기술연구원 청정연료연구실) ;
  • 문지홍 (한국에너지기술연구원 청정연료연구실) ;
  • 이재구 (한국에너지기술연구원 청정연료연구실) ;
  • 주종훈 (광주과학기술원 지구환경공학부) ;
  • 라호원 (한국에너지기술연구원 청정연료연구실)
  • Received : 2023.08.17
  • Accepted : 2023.09.12
  • Published : 2023.12.31
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Abstract

Coal is abundantly available compared to other energy sources and is used as a versatile energy resource worldwide. To address the environmental issues stemming from conventional coal utilization, efforts are underway to develop clean coal utilization technologies, with IGCC technology being a notable example. In IGCC plants, coal is subjected to a CMD process where both drying and pulverization are achieved by supplying hot air. However, if the temperature of the supplied hot air is excessively high, it can lead to devolatilization and spontaneous combustion, thereby compromising the stable operation of the CMD process. This study aimed to measure the devolatilization and spontaneous combustion temperatures of different types of bituminous coal, and to explore their correlations with the characteristics of the coals. Six coal types exhibited devolatilization between 350 and 400 ℃, while three coal types showed devolatilization at temperatures exceeding 400 ℃. Spontaneous combustion ℃curred in one coal type below 100 ℃, six coal types between 100 and 150 ℃, and two coal types above 150 ℃. The measured initiation temperatures were compared with the coal characteristics including the oxygen, moisture, Fe2O3, and CaO content, the H/C ratio, and the O/C ratio to establish correlations. Regression analysis was used to calculate the regression coefficients and determination coefficients for each ignition temperature. It was found that 52.44% of the FC/VM data significantly influenced the volatile matter ignition temperature, and 59.10% of the Fe2O3 data significantly affected the spontaneous combustionignition temperature.

세계적으로 석탄은 다른 에너지원에 비해 매장량이 풍부하여 다양한 에너지원으로 사용되고 있다. 기존 석탄 이용 방식에서 발생하는 환경적인 문제를 해결하기 위해 청정 석탄 활용 기술 개발이 이루어지고 있으며 대표적인 기술로 IGCC발전 기술이 있다. IGCC 발전에서 사용되는 석탄은 CMD 공정에서 열풍을 동시에 공급하여 건조, 분쇄가 이루어지고 있으나, 공급되는 열풍의 온도가 너무 높을 경우, 탈휘발, 자연발화 현상이 발생하게 되고 이로 인한 CMD 공정의 안정적인 운전을 저하시킨다. 본 연구에서는 유연탄 9종을 이용하여 탈휘발, 자연발화 개시온도를 측정하고 석탄 특성분석결과와 함께 상관관계를 알아보고자 하였다. 탈휘발 현상의 경우 350 ~ 400 ℃ 사이에서 6종 석탄의 탈휘발이 확인되었고 400 ℃ 이상의 온도에서 3종의 석탄 탈휘발을 확인하였다. 자연발화의 경우 100 ℃ 이하에서 1종의 석탄, 100 ~ 150 ℃ 사이에서 6종의 석탄, 150 ℃ 이상에서 2종 석탄의 자연발화를 확인하였다. 측정한 개시온도를 석탄 분석 결과 중 Oxygen, Moisture, Fe2O3, CaO, H/C Ratio, O/C Ratio와 비교하여 상관관계를 확인하였다. 회귀분석으로 각 개시온도의 회귀계수와 결정계수를 계산하였으며, FC/VM 데이터의 52.44%가 탈휘발 개시온도에 대해, Fe2O3 데이터의 59.10%가 자연발화 개시온도에 대해 영향을 주는 것에 대한 유의한 결과를 확인 하였다.

Keywords

Acknowledgement

본 연구는 국토교통부/국토교통과학기술진흥원의 지원으로 수행되었음(과제번호 21PCHG-C163217-01).

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