Dissolution of dolomite and doloma in silicate slag

Citation
Y. Satyoko et We. Lee, Dissolution of dolomite and doloma in silicate slag, BRIT CERAM, 98(6), 1999, pp. 261-265
Citations number
7
Categorie Soggetti
Material Science & Engineering
Journal title
BRITISH CERAMIC TRANSACTIONS
ISSN journal
09679782 → ACNP
Volume
98
Issue
6
Year of publication
1999
Pages
261 - 265
Database
ISI
SICI code
0967-9782(1999)98:6<261:DODADI>2.0.ZU;2-0
Abstract
Dissolution mechanisms of dolomite CaMg(CO3)(2), and doloma CaO.MgO, in a m odel basic oxygen furnace (BOF) slag based on the CaO-MgO-SiO2-FeO-MnO syst em have been characterised with regard to the reaction product phases at th e dolomite/slag and doloma/slag interfaces by post-mortem microstructural a nalysis. It was found that after 1 h immersion at 1350 degrees C in a stagn ant molten slag, the CaO and MgO in doloma react with SiO2 and FeO in the s lag forming dicalcium silicate (2CaO.SiO2 or C2S), MgO-rich magnesiowustite ((Fe,Mg)O), and dicalcium ferrite (2CaO.Fe2O3 or C2F). The formation of (F e,Mg)O and C2F breaks up the C2S layer, leaving it discontinuous. Similar r eactions take place in dolomite, but at a later stage of dissolution since they are retarded by the intermediate decomposition of dolomite in which ra pid CO2 gas evolution quenches the resulting C2S layer and forms a fap betw een the resulting doloma and slag. A more complete and continuous dicalcium silicate layer was observed in dolomite compared with doloma.