Journal of Korea Society of Waste Management (한국폐기물자원순환학회지)

Korea Society of Waste Management (한국폐기물자원순환학회)
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Recovery Potential of Rare Earth Elements in Coal Ashes

석탄재 내 희토류 회수 가능성 검토

  • Lee, Jong Keun (Department of Civil and Environmental Engineering, Seoul National University) ;
  • Kim, Jae Young (Department of Civil and Environmental Engineering, Seoul National University)
  • 이종근 (서울대학교 공과대학 건설환경공학부) ;
  • 김재영 (서울대학교 공과대학 건설환경공학부)
  • Published : 2013.01.31
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Abstract

The recovery potential of rare earth elements (REE) in coal ash was evaluated in this study. The previous researches were reviewed, and the physicochemical analysis of coal ash collected from a thermal power plant in Korea was conducted. According to the results of particle-size distribution, fly ash could be classificed as a fine-grained soil by unified soil classification system, and showed a uniform particle size distribution. The particle size of bottom ash was a coarse grained soil and the particle-size distribution was well graded compared to that of fly ash. However, there was no significant difference in the physicochemical composition between both the ashs and particle-size. Although REE was not found in the coal ash specimens used in this study, various valuable metallic compounds were observed. The silicate compounds showed the highest contents being 50% (by wt.), followed by 20 and 10% in aluminum oxide and iron hydroxide. There were also the trace elements in oxide forms (e. g., Ca, Mg, K). Unlike previous researches there are no REE detected in the coal ash specimens used in this study. The composition of ash depends on the coal used in the power plant and the detection limits of analytic instruments may be critical.

Keywords

References

  1. Ichihashi, H, Morita, H. and Tatsukawa, R. : Rare earth elements (REEs) in naturally grown plants in relation to their variation in soils : Environmental Pollution, Vol. 76, pp. 157-162 (1992) https://doi.org/10.1016/0269-7491(92)90103-H
  2. Goldschmidt, V. M. : Rare Elements in Coal Ashes, Industrial and Engineering Chemistry, Vol. 27, No. 9, pp. 1100-1102 (1935) https://doi.org/10.1021/ie50309a032
  3. KEPCO, The Monthly Report on Major Electric Power Statistics, http://cyber.kepco.co.kr/kepco_new/elec_info/info/statistical_data.jsp (2011)
  4. Roy, D. M., Luke, K. and Diamond, S. : Characterization of fly ash and its reactions in concrete, Materials Research Society Symposium Proceedings, Vol. 43, pp. 3-11 (1984)
  5. 장석주, 강승구 : 석탄바닥재로 제작 된 결정화 유리의 특성에 미치는 $TiO_2$의 영향 : 경기대학교 산업기술종합연구소 논문집, Vol. 36 (2009)
  6. 이상혁, 김수생 : 고형화를 이용한 소각재 재활용 : 한국폐기물학회지, Vol. 18, No. 6, pp. 13-21 (2001)
  7. Gutierrez, B., Pazos, C. and Coca, J. : Recovery of Gallium from Coal Fly Ash by A Dual Reactive Extraction Process : Waste Management and Research, Vol. 15, pp. 371-382 (1997) https://doi.org/10.1177/0734242X9701500405
  8. Hernandez-Exposito, A., Chimenos, J. M., Fernandez, A. I., Font, O., Querol, X., Coca, P. and Garcia Pena, F. : Ion flotation of germanium from fly ash aqueous leachates : Chemical Engineering Journal, Vol. 118, pp. 69-75 (2006) https://doi.org/10.1016/j.cej.2006.01.012
  9. Arroyo, F. and Fernandez-Pereira, C. : Hydrometallurgical Recovery of Germanium from Coal Gasification Fly Ash. Solvent Extraction Method : Industrial and Engineering Chemistry Research, Vol. 47, No. 9, pp. 3186-3191 (2008) https://doi.org/10.1021/ie7016948
  10. Volkh, A. A., Gorbunov, A. V., Gundrina, S. F., Revich, B. A., Frontasyeva, M. V. and Pal, C. S. : Phosphorus fertilizer production as a source of rareearth elements pollution of environment : Science of the Total Environment, Vol. 95, pp. 141-148 (1990) https://doi.org/10.1016/0048-9697(90)90059-4
  11. Tsuboi, I., Kunugita, E. and Komasawa, I. : Recovery and Purification of Boron from Coal Fly Ash : Journal of Chemical Engineering of Japan, Vol. 23, No. 4, pp. 480-485 (1990) https://doi.org/10.1252/jcej.23.480
  12. Van Der Flier-Keller, E. : Earth Elements in Wester Canadian Coals : Energy Sources, Vol. 15, No. 4, pp. 623-638 (1993) https://doi.org/10.1080/00908319308909053
  13. Zhang, F. S., Yamasaki, S. and Kimura, K. : Rare earth element in various waste ashes and the potential risk to Japanese soils : Environment International, Vol. 27, pp. 393-398 (2001) https://doi.org/10.1016/S0160-4120(01)00097-6
  14. Zhang, F. S., Yamasaki, S. and Nanzyo, M. : Waste ashes for use in agricultural production: I. Liming effect, contents of plant nutrients and chemical characteristics of some metals : The Science of the Total Environment, Vol. 284, pp. 215-225 (2002) https://doi.org/10.1016/S0048-9697(01)00887-7
  15. Zhang, F. S., Yamasaki, S. and Kimura, K. : Waste ashes for use in agricultural production: II. Contents of minor and trace metals : The Science of the Total Environment, Vol. 286, pp. 111-118 (2002) https://doi.org/10.1016/S0048-9697(01)00968-8
  16. Gutierrez, B., Pazos, C. and Coca, J. : Characterization and Leaching of Coal Fly Ash : Waste Management and Research, Vol. 11, pp. 279-286 (1993) https://doi.org/10.1177/0734242X9301100402
  17. ASTM D 2487, American Society for Testing and Materials
  18. ASTM D 2488, American Society for Testing and Materials
  19. 김명모 : 토질역학, 문운당, pp. 4-9 (2004)