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Manufacturing of Artificial Lightweight Aggregates using a Coal Fly Ash Discharged from Fluidized Bed Combustor

유동층(流動層) 연소기(撚燒器)로 부터 발생(發生)된 석탄(石炭) 비산(飛散)재를 이용(利用)한 인공경량골재(人工輕量骨材) 제조(製造)

  • Kang, Min-A (Department of Materials Engineering, Kyonggi University) ;
  • Kang, Seung-Gu (Department of Materials Engineering, Kyonggi University)
  • 강민아 (경기대학교 신소재공학과) ;
  • 강승구 (경기대학교 신소재공학과)
  • Received : 2010.12.29
  • Accepted : 2011.02.01
  • Published : 2011.02.26

Abstract

The spherical artificial aggregates (AAs) with a diameter of 8 mm, which contains fly ashes discharged from the fluidized bed combustion in a thermal power plant and clay were manufactured by direct sintering method at $1050{\sim}1250^{\circ}C$ for 10 minutes. The effect of fly ash contents on the bloating phenomenon in the AAs was analyzed. The AAs containing fly ash of the amount under 50 wt% showed the black-coring and bloating phenomena. The AAs containing fly ash of the amount over 5Owt%, however, the specific gravity was increased and the color of specimens fully changed to black. These color change phenomena were caused from the formation of FeO by the reduction reaction of almost $Fe_2O_3$ component by the excessive reducing atmosphere formed simultaneously with the rapid emission of the gases generated from the high contents of unburned carbon of with increasing the added fly ash amount. Specific gravity was decreased as fly ash contents increased in the case of sintering at the same temperature condition. Water absorption of all specimens except of the specimens containing 10 wt% fly ashes decreased with increasing sintering temperature. These were because a liquid phase was formed as the increasing the sintering temperature. In the case of the specimens manufactured in this study containing fly ashes discharged from the fluidized bed combustor in a the thermal power plant and 10~90 wt% of clay, the specific gravity was 0.9~1.8 and the water absorptivity was 8~60%, therefore it is considered that those results can be applied to the light or heavy aggregates.

References

  1. K. D. Kim and S. G. Kang, 2007: Manufacturing artificial lightweight aggregates using coal bottom ash and clay, J. of the Korean Crystal Growth and Crystal Technology, 17(6), pp277-282.
  2. K. D. Kim, J. H. Kim, Y. T. Kim and S. G. Kang, K. G. Lee, 2010: Production of Lightweight Aggregates Using Power plant Reclaimed Ash, Journal of the Korean Ceramic Society, 47(6), pp583-589. https://doi.org/10.4191/KCERS.2010.47.6.583
  3. K. D. Kim, 2010: A Study on application and fabrication of functional ceramics for constructing materials using ecofriendly waste recycling process, Kyonggi University graduate school a doctoral dissertation.
  4. D. H. Shin, J. H. Hwang, J. M. Lee and D. W. Kim, J. S. Kim, 2004: A Study on Design Optimization of Circulating Fluidized Bed Boiler for Domestic Anthracite, J. of the Korea society for energy engineering, pp287-292.
  5. S. M. Kim, J. M. Lee, J. S. Kim, K. G. Song, 2000: Evaluation of Performance for The Tonghae CFBC with Operation Parameters, J. of Korea society for energy engineering, 9(3), pp250-260.
  6. Riley, C. M., 1951: Relation of chemical properties to the bloating of clay, J. of Amec. Ceram. Soc., 34(4), pp121-128. https://doi.org/10.1111/j.1151-2916.1951.tb11619.x
  7. Y. J. Kwon, J. H. Kim, Y. T. Kim and S. G. Kang, K. G. Lee, 2001: Lightweight Aggregate Bloating Mechanism of Clay/Incinerated Ash/Additive System, Journal of the Korean Ceramic Society 38(9), pp811-816.
  8. H. J. Lee, D. W. Kim, Y. T. Kim and S. C. Hong, K. G. Lee, 1993: Analysis of Coal Fly Ash, Journal of the Korean crystal growth and crystal technology, 3(2), pp185-201.
  9. J. Y. Park, Y. T. Kim, K. G. Lee, S. G. Kang, and J. H. Kim, 2005: The Mechanism of Black Core Formation, J. of the Korean Crystal Growth and Crystal Technology, 15(5), pp208-215.
  10. J. Y. Park, Y. T. Kim, K. G. Lee, S. G. Kang, and J. H. Kim 2005 : Microstructural observation of artificial aggregates at various sintering atmospheres, J. of the Korean Crystal Growth and Crystal Technology, 16(2) pp71-75.

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