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Interceram - International Ceramic Review

, Volume 67, Supplement 1, pp 32–37 | Cite as

Effect of SiO2 Micropowder on Properties of Calcium Hexaluminate Castables for Coal Catalytic Gasifiers

  • Luo Qiong
  • Gu Huazhi
  • Yu Yalan
  • Huang Ao
  • Zhang Meijie
  • Luo Zhian
Applications and Engineering Furnace Linings
  • 2 Downloads

Abstract

Furnace lining materials for coal catalytic gasifiers should have good high-temperature strength and alkali slag corrosion resistance. Calcium hexaluminate castable is a promising application direction. In this paper, the effect of the addition of SiO2 micropowder on the performance of a calcium hexaluminate castable was evaluated through sintered properties, high-temperature strength, anti-alkali slag performance, and microstructural analysis. The results show a significant increase of grain and matrix bonding strength and a decrease of porosity with SiO2 micropowder addition. The castables with 3 mass-% SiO2 micropowder possessed 14.3 MPa CMOR (Cold Modulus of Rupture) and 107.6 MPa CCS (Cold Crush Strength) after heat treatment at 800 °C for 3 h. The hot flexural strength is 11.8 MPa and the retained residual flexural strength of the castables reached 37.13 % after five thermal shock cycles (water cooling) at 1100 °C. The potassium element in the slag has a very small amount of penetration and aggregation at the interface between the sample and the slag.

Keywords

calcium hexaluminate castable SiO2 micropowder high-temperature strength alkali slag resistance 

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Copyright information

© Springer Fachmedien Wiesbaden GmbH, part of Springer Nature 2018

Authors and Affiliations

  • Luo Qiong
    • 1
  • Gu Huazhi
    • 1
  • Yu Yalan
    • 1
  • Huang Ao
    • 1
  • Zhang Meijie
    • 1
  • Luo Zhian
    • 1
  1. 1.The State Key Laboratory of Refractories and MetallurgyWuhan University of Science and TechnologyWuhanChina

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