As an advanced technology, carbonation reaction could dispose of industrial solid residues and sequestrate CO2 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 C3S, C2S, C3A, C4AF were 1550°C,1400°C,1330°C, 1350°C). Forming and unforming main cement minerals and clinker were carbonated under the condition of CO2 partial pressure P=0.2MPa, T =25°C, CO2 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 (C3S, C2S, C3A and C4AF), and CaCO3 crystals appeared in these minerals. The sequence of carbonation degree of minerals were C3S﹥C2S﹥C4AF﹥C3A. 0.168g and 0.125g CO2 gas could been sequestrated by 1 gramme of C3S and C2S in carbonated curing respectively, and 0.1301g and 0.1464 g CO2 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.
Study of the pitting corrosion at welding joints of Inconel 625 alloy under high temperature and high H2S/CO2 partial pressure
