Study on Effect of Carbonation Curing for Cement Minerals and Clinker

摘要

As an advanced technology, carbonation reaction could dispose of industrial solid residues and sequestrate CO_2 gas, save resources and protect environment. In this study, Major minerals of cement were high-temperature burned using pure chemical reagents ( the burning temperature of C_3S, C_2S, C_3A, C_4AF were 1550℃,1400℃,1330℃, 1350℃). Forming and unforming main cement minerals and clinker were carbonated under the condition of CO_2 partial pressure P=0.2MPa, 7=25℃, CO_2 gas concentration c>99.9% and water/soild w/s=0.12kg/kg. The change of minerals and the effect of carbonation were tested. The experimental results showed that carbonation reaction could been occured in four cement minerals (C_3S, C_2S, C_3A and C_4AF), and CaCO_3 crystals appeared in these minerals. The sequence of carbonation degree of minerals were C_3S > C_2S > C_4AF > C_3A. 0.168g and 0.125g CO_2 gas could been sequestrated by 1 gramme of C_3S and C_2S in carbonated curing respectively, and 0.1301g and 0.1464 g CO_2 gas could been sequestrated by 1 gramme of formed and powdery clinker. After carbonated curing, clinker samples had high early strength and good soundness, 2h strength was 24.65 MPa and 3d strength was 41.65 MPa.