본 연구에서는 탄소 포집 물질인 γ-C2S를 함유하고 있는 Stainless Steel Slag AOD를 포함한 시멘트 페이스트의 역학적 및 미세구조 변화를 연구하였다. γ-C2S는 비수경성이며 그러므로 물과 반응하지 않는다. 그러나 γ-C2S는 물에 의한 탄산화 양생조건에서 반응성을 가지고 있다. 그 반응은 페이스트 안의 공극을 치밀하게 형성하기 때문에 STS-A를 사용한 시멘트 페이스트의 공극구조는 탄산화 (CO2 농도는 약 5%)후에 수은압입시험에 의해 측정될 수 있다. 또한 Fractal 특성은 시멘트 페이스트의 미세구조변화는 탄산화 영향에 대하여 연구하였다. 그 결과로부터 STS-A를 포함하는 탄산화 시멘트 페이스트는 강도가 증가하였고 공극구조는 더 치밀해졌다.

Steel slag has been used as the alternative binder to replace Portland cement that furthermore used as in construction and/or for stabilization/solidification of heavy metals in mine soil. One of the treatments to modify the leaching behavior of the mine soil is by carbonation. The purpose of this study was to assess the potential of carbonation in various steel slags. Based on chemical and mineralogical characterization of four kinds of slag that were used in this study, it showed that all slags had high potential for reacting with CO2 that was in accordance with the high CaO and MgO content. CO2 sequestration by aqueous carbonation of several kinds of stainless steel slags with different liquid to solid ratio was investigated in this study. The effect of chemical properties and reaction time on the performance of the carbonation process was also investigated. Converter slag, blast furnace slag (BFS) and ladle furnace slag (LFS) were used. Carbonation experiment was conducted in a closed reactor under the conditions; 1bar, 400rpm and 25℃, with solid to liquid ratios of 0.4, 0.6 and 1.0. Carbonation kinetic test was relatively fast and completed within 5 hours. The CO2 consumption increased when the liquid to solid ratio increased because of the dilution effect. Our results showed that the higher CaO and MgO contents in the slag, the higher CO2 consumption was observed. Pohang converter slag and Dangjin LFS showed slightly different tendency. At L/S ratio 0.4, Pohang slag with higher CaO and MgO content had higher CO2 consumption than Dangjin LFS. As the water content increased, Dangjin LFS had higher CO2 consumption than Pohang converter slag that was caused by the texture of Dangjin LFS with smaller particle size than Pohang converter slag. However, both Pohang BFS and Dangjin BFS have poor capacity in CO2 sequestration.