DOI QR코드

DOI QR Code

Effect of modifiers on the properties of glass-ceramics containing coal bottom ash

석탄 바닥재가 포함된 결정화 유리의 특성에 미치는 수식제의 영향

  • Kang, Seung-Gu (Department of Advanced Materials Engineering, Kyonggi University)
  • Published : 2010.02.28

Abstract

The influence of CaO addition on the crystallization temperature, crystal types, and microstructure of L-A-S ($Li_2O-Al_2O_3-SiO_2$) glass-ceramics system fabricated from a coal bottom ash, produced at thermal power plant, was studied. The glass transition and crystallization temperatures were shifted to the higher temperature position with increasing CaO content in a non-isothermal analysis using a DTA. The major crystalline phases of L-A-S glass-ceramics system produced were identified as ${\beta}$-spodumene ($LiAlSi_2O_6$) and eucryptite ($LiAlSiO_4$). The glass-ceramics showed a bulk and surface crystallization behavior at a time. With increasing CaO content, the ${\beta}$-spodumene peak in XRD increased and some CaO-related phases were formed. The surface crystal grown from the exterior to the center in glass-ceramics showed various shapes by amount of CaO added. Some cracks were generated at the glass-ceramics containing CaO above 9 wt% due to the mismatch of thermal expansion coefficients between a ${\beta}$-spodumene and CaO-related crystal phases.

화력 발전소에서 배출된 석탄 바닥재로 L-A-S($Li_2O-Al_2O_3-SiO_2$)계 결정화 유리를 제조함에 있어 수식제인 CaO 첨가가 결정화 온도, 결정상 종류, 미세구조 등의 특성에 미치는 영향을 분석하였다. L-A-S계 유리에 CaO를 첨가하면 DTA 그래프 상의 유리 전이 온도 및 결정화 온도가 함께 높아지고 주 결정상으로 ${\beta}$-spodumene($LiAlSi_2O_6$) 및 eucryptite ($LiAlSiO_4$)가 생성되었으며, 동시에 CaO와 관련된 미지의 상도 약간 생성되었다. 결정화 유리 시편은 표면 및 내부 결정화 거동을 함께 나타냈으며, CaO 첨가량이 증가하면 시편 내부의 결정 크기 및 분율이 높아졌다. 또한 시편의 겉에서 내부 방향으로 성장한 표면 결정은, CaO 첨가에 따라 다양한 형태를 보였으며 CaO 첨가량이 9 wt% 이상이 되면 일부 균열이 관찰되었는데 이는 ${\beta}$-spodumene과 CaO 관련 결정 간에 열팽창계수 차이에 의한 것으로 생각된다.

Keywords

References

  1. S.U. Shin, S. Kumar, T.U. lung and B.W. Shin, "The strength and characteristic of PCC bottom ash", J. Kor. Geo-Environ. Soc. 8(2) (2007) 57.
  2. D.U. Lee and Y.S. Kim, "A study on the strength properties of concrete containing bottom ash as a part of fine aggregate", J. Architectural Institute of Korea 22(6) (2006) 79.
  3. Carlos P. Bergmann, "Sinterability study of ceramic bodies made from a mixture of mineral coal bottom ash and soda-lime glass cullet", Waste Manage Res. 25 (2007) 77. https://doi.org/10.1177/0734242X07069764
  4. C.T. Kniess, C.D.G. de Borba, E. Neves, N.C. Kuhnen and H.G. Riella, "Obtaining and characterizing $Li_2O-Al_2O_3-SiO_2$ glass-ceramics using bottom ash as raw material", Interceram 51 (2002) 140.
  5. S.J. Jang and S.G. Kang, "Microstructural analysis for hybrid materials composing of nepheline crystal and glass matrix fabricated from coal bottom ash", J. Ceram. Proc. Res. 10(1) (2009) s59.
  6. S.G. Kang, "Microstructure of glass-ceramics made from bottom ash produced at a thermal power plant", Kor. J. Mater. Res. 19(2) (2009) 95. https://doi.org/10.3740/MRSK.2009.19.2.095
  7. Y. Masauki, "Glasses", Translated to Korean by W.H. Kang, et al., Chungmoongak, Korea (2202) 34.
  8. M.F. Berard and D.R. Wider, Fundamentals of Phase Equilibria in Ceramic Systems, p.25, R.A.N., USA (1990).

Cited by

  1. Effects of forming and cooling temperature on the opaque properties of translucent opal glass for the glass diffuser of LED lighting vol.23, pp.5, 2013, https://doi.org/10.6111/JKCGCT.2013.23.5.246
  2. Characteristics of green colored opal glass with contents of iron oxide for LED light diffuser vol.24, pp.3, 2014, https://doi.org/10.6111/JKCGCT.2014.24.3.120