Study on Manufacture Steel Slag Cement by CO2 curing of Steel Slag

摘要

Carbonation technology was used to cure coarse steel slag powder for preparing steel slag cement. Under temperature T=70 °C, CO2 gas concentration c=99.5% and CO2 partial pressure P=0.16 MPa, steel slag powder was carbonated in an autoclave for 270 min. Then after drying, carbonated steel slag powder was mixed with clinker, slag and gypsum to manufacture steel slag cement. The experimental results showed that, the f-CaO content of steel slag powder fell from 5.67 w% to 0.34 w% after carbonation,, and most of the f-CaO was transformed into CaCO3 crystals. When the mixing amount of carbonated steel slag powder was 40 w%, the 3 d and 28 d strength of this steel slag cement were 20.6 MPa and 44.7 MPa respectively, and autoclave soundness were eligible.