Browse > Article

Characteristics of artificial lightweight fine aggregates manufactured by using a vertical fluidizing furnace  

Kang, Seung-Gu (Department of Materials Engineering, Kyonggi University)
Publication Information
Journal of the Korean Crystal Growth and Crystal Technology / v.19, no.1, 2009 , pp. 54-59 More about this Journal
Abstract
It was difficult for the existing rotary kiln to fabricate the fine aggregates under 3 mm due to the sticking phenomenon between specimens. In this study, the vertical type fluidizing furnace was designed and manufactured by which the lightweight fine aggregates of specific gravity $1.1{\sim}1.7$, water absorption $11{\sim}19%$ could be fabricated from the green body of clay: stone sludge: spent bleaching clay = 60 : 30 : 10 (wt%) without sticking-together happening. The minimum sintering temperature for bloating of aggregates was $1130^{\circ}C$. The specimens sintered over $1140^{\circ}C$ showed the typical bloating characteristics of lightweight aggregates and an inner layer was discovered due to widened cracks on a surface. But the crack on a surface did not propagate into a black core area so had no effect on a water absorption of aggregates. The sintering temperature made the thickness of shell and the black core area thin and expanded respectively but the sintering time did not affect the microsturcture of aggregates. The water absorption of aggregates decreased with increasing temperature owing to increased amount of liquid formed on a surface. Also sintering time affected a lot on a water absorption because it takes a time to form a liquid, which change the open pores to closed pores by blocking.
Keywords
Fluidizing furnace; Bloating; Fine aggregates; Specific gravity; Water absorption; Black core;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
1 T.Y. Lo, H.Z. Cui and Z.G. Li, "Influence of aggregate pre-wetting and fly ash on mechanical properties of lightweight concrete", Waste Management 24 (2004) 333   DOI   ScienceOn
2 C.R. Austin, J.L. Nunes and J.D. Sulivan, "Basic factors involved in bloating of clays", American Institute of Mining and Metallurgical Engineers Technical Publication 1486 (1942) 1
3 F. Negre, A. Barba, J.L. Amoros and A. Escardino, "Oxidation of black core during the firing of ceramic ware-2. process kinetics", Br. Ceram. Trans. 91 (1992) 5
4 C.P. Choi and S.G. Kang, "Design and fabrication of vertical type fluidized furnace for manufacturing lightweight fine aggregates", J. Ceram. Poc. Res. (2009) to be published
5 Daizo Kunii and Octave Levenspiel, "Fluidization engineering", 2nd ed (Butterworths, London, 1991) p.68
6 J.Y. Jeong, S.M. Choi, E.G. Kwag, S.J. Choi, S.Y. Lee and J.M. Kim, "The strength properties of concrete used stone powder sludge as siliceous material", Journal of the Korean Institute of Construction 5 (2005) 85   과학기술학회마을
7 C.M. Riley, "Relation of chemical properties to the bloating of clay", J. Am. Ceram. Soc. 34 (1951) 121   DOI
8 T.Y. Lo and H.Z. Cui, "Effect of porous lightweight aggregate of strength of concrete", Materials Letters 58 (2004) 916   DOI   ScienceOn
9 S. Kimura, K. Kimura, H. Kamiya and M. Horio, "A novel fluidized bed process to produce fine-grade artificial lightweight aggregates", Powder Technology 146 (2004) 111   DOI   ScienceOn
10 S.J. Choi, S.Y. Lee, B.C. Yeo and M.H. Kim, "An experimental study on the properties of crushed sand in capital region and concrete according to the replacement ratio of crushed sand", Journal of the Korean Institute of Construction 5 (2005) 63   과학기술학회마을   DOI   ScienceOn