Improvement of Gaseous Corrosion Resistance of Refractories by Pore Structure Design According to the Seepage Flow Model

Xu Yibiao, Li Yawei, Sang Shaobai, Ren Bo

The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081/China

Revision 27.01.2016, 15.02.2016

Volume 8, Issue 3, Pages 111 - 117

Abstract

Pore structure is one of the most critical parameters for refractories when they are attacked by the corrosive vapour. The infiltration process of corrosive gaseous phases into the refractories can be regarded as gas seepage flow in the porous media. In this paper, the seepage flow model was put forward and experimental verifications have been carried out. The developed capillary model shows the main factors that affect the seepage flow rates are pore size distribution and effective porosity. The alkaline vapour attack test of Al2O3–C and bauxite-SiC refractories confirmed that the resistance to alkali corrosion of these materials was strongly influenced by the pore size distribution. The vapour attack of the refractories can be restricted by the pore structure design. The decrease of mean pore size and effective porosity, especially the reduction of the proportion of large pores are beneficial to decrease the alkali vapour from infiltrating into the refractories, which can improve the vapour attack resistance of the refractory at high temperature.

Keywords

gaseous corrosion, pore structure, seepage flow model

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