Wang Kang, Zheng Hao, Li Shanhu, Sun Yu, Ba Haojing, Ma Juntao
Hubei Provincial Academy of Building Research and Design Co., Ltd, 430071, Wuhan, China.
International Joint Research Lab for Eco-building Materials and Engineering of Henan, North China University of Water Resources and Electric Power, Zhengzhou, 450045, China.
Sci Rep. 2025 Apr 30;15(1):15199. doi: 10.1038/s41598-025-99803-1.
The carbonation of steel slag (SS) can enhance its performance while capturing CO. The synergistic effect of combining multi-solid waste materials improves SS's carbon sequestration efficiency, thereby contributing to reduce carbon emissions. This study investigates the synergistic carbonation mechanism of SS when combined with calcium carbide slag (CCS) and desulfurization gypsum (DG) under various water-to-binder ratios (w/bs). The mineral evolution, carbon sequestration performance, and carbon footprint of the multi-solid waste composite system are comprehensively analyzed. The results indicate that, at different w/bs, most SS-CCS-DG composite pastes exhibit a significant strength increase after carbonation compared to carbonated SS paste. Specifically, the strength of the 89%SS-5%CCS-6%DG paste is 44% and 60% higher than that of carbonated SS pastes at 0.15 and 0.3 w/bs, respectively. Carbon sequestration and carbon footprint analysis show that after carbonation, the composite system effectively sequesters 12.2% CO, with an actual carbon sequestration rate surpassing 70% of its theoretical value. Compared to the SS system, the composite system achieves a higher negative carbon emission of -279.93 kg CO/t.
钢渣（SS）的碳酸化作用在捕获二氧化碳的同时可提升其性能。多种固体废料相结合的协同效应提高了钢渣的碳封存效率，从而有助于减少碳排放。本研究探究了在不同水胶比（w/bs）下，钢渣与电石渣（CCS）和脱硫石膏（DG）结合时的协同碳酸化机理。对多固体废料复合体系的矿物演化、碳封存性能及碳足迹进行了全面分析。结果表明，在不同水胶比下，与碳酸化后的钢渣浆体相比，大多数钢渣-电石渣-脱硫石膏复合浆体碳酸化后强度显著提高。具体而言，89%钢渣-5%电石渣-6%脱硫石膏浆体在水胶比为0.15和0.3时，强度分别比碳酸化后的钢渣浆体高44%和60%。碳封存和碳足迹分析表明，碳酸化后，复合体系有效封存了12.2%的二氧化碳，实际碳封存率超过其理论值的70%。与钢渣体系相比，复合体系实现了更高的负碳排放，为-279.93千克二氧化碳/吨。
