Experiments of electric furnace simulator for property prediction of the artificial lightweight aggregate sintered by rotary kiln

로타리킬른 소성 골재 물성예측을 위한 전기로 실험

  • Ryu, Yug-Wang (Department of Materials Engineering, Kyonggi University) ;
  • Kim, Yoo-Taek (Department of Materials Engineering, Kyonggi University)
  • Published : 2008.06.30

Abstract

If the properties of artificial lightweight aggregates produced by rotary kiln can be predicted by using a simulator equipped with a small electric furnace and a specially designed device for specimen movement, large amount of raw materials and plenty of test time can be saved to produce test products of lightweight aggregates. In this study a simulator for the accurate prediction of the artificial lightweight aggregates produced by rotary kiln was assembled by our own design and the properties of lightweight aggregates produced by both the simulator and rotary kiln were compared to speculate its usefulness. The average diameter of aggregates was 8 mm and atmosphere in the furnace was controlled by the amount of carbon powders. Specific gravity, absorption rate (%), black-core area in the cross-sectional view of both aggregates were measured and compared. Unlike oxydizing atmosphere, both specific gravity and absorption rate of the aggregates sintered at reducing atmosphere were increased with increasing carbon addition. It is concluded that the sintering atmosphere was the closest to that of the rotary kiln when the carbon addition was 0.7 g to make a reducing atmosphere in the furnace and the properties of both agreggates was also similar to each other.

소형 전기로 및 이동장치가 있는 시뮬레이터를 사용하여 로타리킬른에서 생산되는 인공경량골재의 물성을 예측 할 수 있다면 대규모 로타리 킬른을 사용하여 인공경량골재 시제품 생산할 때 필요한 물자와 시간을 대폭 절감할 수 있다. 본 실험에서는 생산될 인공경량 골재의 물성을 정확히 예측할 수 있는 시뮬레이터를 제작하여 실제 로타리 킬른에서 생산된 골재의 물성과 비교함으로써 그 유용성을 검토하고자 하였다. 골재의 물성을 예측하기 위해서 8 mm 크기의 에코 인공경량 골재를 사용하였고 시뮬레이터의 분위기를 탄소를 이용해 조절하였다. 시뮬레이터와 로타리킬른에서 소성된 골재의 비중, 흡수율, 골재의 단면의 면적을 측정하고 비교하였다. 산화 분위기와 달리 환원분위기에서 소성된 시편은 탄소량이 증가할수록 비중이 증가하였으며 흡수율은 탄소 첨가량이 증가할수록 증가하는 경향을 보였다. 소성분위기는 환원 분위기 조성을 위해 탄소분말 0.7g을 첨가하였을 때 로라리 킬른과 가장 흡사한 분위기가 형성되는 것으로 판단되며, 두 골재의 물성 역시 비슷하였다.

Keywords

References

  1. C.S. Yi and B.S. Kim, "A computer simulation of transport phenomena in a roller kiln", Journal of RIEET 5 (1999) 133
  2. Y.M. Wie and K.G. Lee, "Correlation to the physical prorerties of green and sintered body of artificial lightweight aggregate with the pelletizing variables", Jounal of the Korean Ceramic Society 44 (2007) 568 https://doi.org/10.4191/KCERS.2007.44.1.568
  3. J.U. Park and Y.T. Kilm, "Microstructural observation of article aggregaters at various sintrring atmospheres", J. Kor. Crystal Growth and Crystal Technology 16 (2006) 71
  4. J. Pacini, "Bloating and black coring", Laguna Clay Co, January (1999)
  5. Y.J. Joo and M.S. Oh, "Unbunt carbon combustion in the production of light weight sintered fly ash", Proceeding of KSEE Conference (2002) 91
  6. F. Negre, A. Barba, J.L. Amoros and A. Escarkino, "Oxidation of black core during the firing of ceramic ware-2. process kinetics", Br. Ceram. Trans. J. 91 (1992) 5
  7. KS F 2503 Absorption Rate and Density Test Method for Fine Aggregates