Ju Jiantao, Cao Haibo, Guo Wenke, Luo Ning, Zhang Qiming, Wang Yonggang
School of Metallurgical Engineering, Xi'an University of Architecture and Technology, Xi'an 710200, China.
Gansu Jiugang Group Hongxing Iron and Steel Co., Ltd., Jiayuguan 735100, China.
Materials (Basel). 2024 May 13;17(10):2305. doi: 10.3390/ma17102305.
In order to increase the utilization rate of stainless steel slag, reduce storage needs, and mitigate environmental impacts, this study replaces a portion of limestone with varying amounts of stainless steel slag in the calcination of Portland cement clinker. The study primarily examines the influence of stainless steel slag on the phase composition, microstructure, compressive strength, and free calcium oxide (ƒ-CaO) content of Portland cement clinker. The results show the following: (1) Using stainless steel slag to calcine Portland cement clinker can lower the calcination temperature, reducing industrial production costs and energy consumption. (2) With an increase in the amount of stainless steel slag, the dicalcium silicate (CS) and tricalcium silicate (CS) phases in Portland cement clinker initially increase and then decrease; the CS crystals gradually transform into continuous hexagonal plate-shaped distributions, while the tricalcium aluminate (CA) and tetracalcium aluminoferrite (CAF) crystal structures become denser. When the stainless steel slag content is 15%, the dicalcium silicate and tricalcium silicate phases are at their peak; the CS crystals are continuously distributed with a relatively dense structure, and CA and CAF crystals melt and sinter together, becoming distributed around CS. (3) As stainless steel slag content increases, the compressive strength of Portland cement clinker at 3 days, 7 days, and 28 days increases and then decreases, while ƒ-CaO content decreases and then increases. When the stainless steel slag content is 15%, the compressive strength at 28 days is at its highest, 64.4 MPa, with the lowest ƒ-CaO content, 0.78%. The test results provide a basis for the utilization of stainless steel slag in the calcination of Portland cement clinker.
为提高不锈钢渣的利用率，减少储存需求，并减轻环境影响，本研究在硅酸盐水泥熟料煅烧过程中用不同量的不锈钢渣替代部分石灰石。该研究主要考察不锈钢渣对硅酸盐水泥熟料的相组成、微观结构、抗压强度和游离氧化钙（ƒ-CaO）含量的影响。结果表明：（1）使用不锈钢渣煅烧硅酸盐水泥熟料可降低煅烧温度，降低工业生产成本和能源消耗。（2）随着不锈钢渣用量的增加，硅酸盐水泥熟料中的硅酸二钙（CS）和硅酸三钙（CS）相先增加后减少；CS晶体逐渐转变为连续的六边形板状分布，而铝酸三钙（CA）和铁铝酸四钙（CAF）晶体结构变得更致密。当不锈钢渣含量为15%时，硅酸二钙和硅酸三钙相达到峰值；CS晶体连续分布且结构相对致密，CA和CAF晶体熔融烧结在一起，分布在CS周围。（3）随着不锈钢渣含量增加，硅酸盐水泥熟料3天、7天和28天的抗压强度先增加后降低，而ƒ-CaO含量先降低后增加。当不锈钢渣含量为15%时，28天抗压强度最高，为64.4MPa，ƒ-CaO含量最低，为0.78%。试验结果为不锈钢渣在硅酸盐水泥熟料煅烧中的利用提供了依据。
