POST MORTEM STUDY OF REFRACTORIES LINING
OF BLAST FURNACE HEARTH.
Vidal, B. A.1, Vernilli, F. J.1, 2.
1
Universidade de São Paulo - Campus Lorena, SP – Brazil
2
Companhia Siderúrgica Nacional – CSN, RJ – Brazil
This study had like objective determined the main mechanisms of corrosion and wear, after
“post mortem” analysis of the refractory lining of CSN #2 Blast Furnace. The samples for this
study were collected during the Blast Furnace refitment accomplished in may of 2009.
Materials collected at different depths were characterized by means of the techniques of
chemical analyses, X-ray diffraction, mercury porosimetry, optical microscopy and scanning
electron microscopy coupled to an electronic microprobe.
As a result of this study, the corrosion mechanisms of the refractory’s lining was modeled.
The mechanism is fundamentally governed by the attack of CaO and Na2O (originated from
the aluminum dross), both present in the slag, to the matrix of the refractory, rich in carbon
containing phases. Laboratorial slagging simulations were carried out in a high frequency
induction furnace aiming at reproducing the operational conditions of usage of the refractory
linings.
The results will be used to predict the campaign of new refractory’s of the CSN Blast
Furnace, guarantying therefore the supply of high quality pig iron to its Steel Plant.
Keywords: Refractory, Blast Furnace, Post mortem analysis.
Work supported by: FACTE and Companhia Siderúrgica Nacional – CSN.
1. SILVA, S. N. Deposição química de titânio em refratários de carbono de cadinho de alto
forno para prevenção contra corrosão. 1998. 425 f. Tese (Doutorado em Engenharia de
Materiais) Universidade Federal de São Carlos, São Carlos, 1998.
2. VERNILLI, F. Deposição Química de Cério e Zircônio em Refratários de Carbono para
Prevenção Contra Corrosão em Cadinhos de Alto Forno. 2003. 98 f. Tese (Doutorado em
Qumica) Universidade Estadual Paulista, Araraquara, 2003.
3. HIRAGUSHI, K. et al “A New Approach to Blast Furnace Stack Linings”. Iron and Steel
Engineer. p. 47-53, 1978.
[email protected],
Escola de Engenharia de Lorena, Universidade São Paulo
Departamento de Engenharia de Materiais, Lorena - SP