Aluminum-rich belite sulfoaluminate cements: Clinkering and early age hydration
Aluminum-rich belite sulfoaluminate cements: Clinkering and early age hydration
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DOI：
10.1016/j.cemconres.2009.11.003
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发表时间：
2010-03-01
影响因子：
11.4
通讯作者：
Aranda, Miguel A. G.
中科院分区：
文献类型：
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作者：
Carmen Martin-Sedeno, M.;Cuberos, Antonio J. M.;Aranda, Miguel A. G.
贝利特硫铝酸盐(BSA)水泥已被推荐为环保型建筑材料，因为与普通波特兰水泥相比，其生产过程向大气中排放的二氧化碳最多可减少35%。在这里，我们讨论了三种富铝牛血清白蛋白熟料的实验室生产，其标称矿物组成范围为C2S(50-60%)、C(4)A(3)$(20-30%)、CA(10%)和C(12)A(7)(10%)。利用热重分析、差热分析、高温显微镜、X射线粉末衍射和Rietveld定量物相分析，我们发现在这些实验条件下，在1350℃下燃烧15min是获得最高C(4)A(3)$的最佳程序，即尽可能接近标称组成的值。在本实验条件下，经Rietveld分析，三种不同质量分数的BSA熟料的C(4)A(3)$的质量分数分别为19.6%、27.1%和27.7%。我们还研究了由BSA熟料和石膏混合制备的BSA水泥的复合水化过程。我们提出了一种方法来建立BSA水泥浆体的相组合随时间的演变，包括无定形相和自由水。该方法基于同步加速器的Rietveld定量物相分析和实验室X射线粉末衍射数据，并结合化学约束。还报道了一项平行的量热研究。结果表明，与标准贝利特水泥相比，富铝BSA水泥中的β-C2S相更具活性。另一方面，C(4)A(3)$的反应速度比贝利特相快。石膏在水泥中的比例也是影响水泥相演变的重要因素。(C)2009爱思唯尔有限公司。保留所有权利。
Belite sulfoaluminate (BSA) cements have been proposed as environmentally friendly building materials, as their production may release up to 35% less CO2 into the atmosphere when compared to ordinary Portland cements. Here, we discuss the laboratory production of three aluminum-rich BSA clinkers with nominal mineralogical compositions in the range C2S (50-60%), C(4)A(3)$ (20-30%), CA (10%) and C(12)A(7) (10%). Using thermogravimetry, differential thermal analysis, high temperature microscopy, and X-ray powder diffraction with Rietveld quantitative phase analysis, we found that burning for 15 min at 1350 degrees C was the optimal procedure, in these experimental conditions, for obtaining the highest amount of C(4)A(3)$, i.e. a value as close as possible to the nominal composition. Under these experimental conditions, three different BSA clinkers, nominally with 20,30 and 30 wt.% of C(4)A(3)$, had 19.6, 27.1 and 27.7 wt.%, C(4)A(3)$ respectively, as determined by Rietveld analysis. We also studied the complex hydration process of BSA cements prepared by mixing BSA clinkers and gypsum. We present a methodology to establish the phase assemblage evolution of BSA cement pastes with time, including amorphous phases and free water. The methodology is based on Rietveld quantitative phase analysis of synchrotron and laboratory X-ray powder diffraction data coupled with chemical constraints. A parallel calorimetric study is also reported. It is shown that the beta-C2S phase is more reactive in aluminum-rich BSA cements than in standard belite cements. On the other hand, C(4)A(3)$ reacts faster than the belite phases. The gypsum ratio in the cement is also shown to be an important factor in the phase evolution. (C) 2009 Elsevier Ltd. All rights reserved.