Evaluation of refractory brick classes for the Cerro Matoso S.A. electric furnace

CIM Bulletin, Vol. 92, No. 1031, 1999

J.R. Donald, P.H. Lauzon, Hatch Associates, Mississauga, Ontario, J. Duran, R. Parra and L. Tejeda, Cerro Matoso S.A., Bogota, Colombia

Crucible slag tests were employed to evaluate different refractory brick classes for the Cerro Matoso electric furnace. Comprehensive analysis was conducted to evaluate the crucible erosion and characterize any slag/refractory reaction products. The classes of refractories investigated were: • tar-impregnated magnesia; • rebonded fused grain magnesia-chrome; • direct bonded magnesia-chrome; • alumina-chrome; • picrochromite; and • magnesia-alumina (spinel). It was concluded that tar-impregnated MgO bricks were the most suitable for the slag chemistry and furnace environment according to corrosion and infiltration resistance. A picrochromite (MgCr2O4) brick performed exceptionally well with regards to erosion resistance, however, the slag infiltrated extensively through the brick pores. Alumina-chrome, direct bonded magnesia-chromite, and spinel (magnesia-alumina) bricks were evaluated as not suitable for use in the furnace.
Keywords: Metallurgy, Refractory brick, Crucible slag tests.