Evaluation of alkali-activated blast furnace ferronickel slag as a cementitious material: Reaction mechanism, engineering properties and leaching behaviors
Evaluation of alkali-activated blast furnace ferronickel slag as a cementitious material: Reaction mechanism, engineering properties and leaching behaviors
复制标题
碱激发高炉镍铁渣作为胶凝材料的评价：反应机理、工程性能和浸出行为
DOI：
10.1016/j.conbuildmat.2018.08.182
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发表时间：
2018-11-10
影响因子：
7.4
通讯作者：
Yang, Jun
中科院分区：
文献类型：
--
作者：
Wang, Dengquan;Wang, Qiang;Yang, Jun
高炉镍铁渣是在高炉冶炼镍铁过程中产生的一种含钙量适中的重金属渣。研究了碱激发BFFS材料的反应机理、工程性能和浸出行为。结果表明，反应产物的主晶相为钠闪石，凝胶相为C-A-S-H，Ca/Si比为0.64-1.65，Al/Si比为0.57-1.44。BFFS的反应在很大程度上取决于碱度和硅模数，高碱度和低硅模数导致碱激活的BFFS材料的快速初始放热速率、高反应程度和更致密的孔结构。此外，碱激发BFFS砂浆的抗压强度与碱激发高炉矿渣（BE）的抗压强度相当;此外，碱激发BFFS从7天到90天显示出更多的连续强度增益和更低的7天自收缩。更重要的是，碱活化处理可以显着降低Mn，Cr（VI）和Cr（III）的浸出量，并将有害的BFFS转化为无毒的建筑材料。(C)2018爱思唯尔有限公司版权所有
Blast furnace ferronickel slag (BFFS) is a kind of heavy metal-bearing slag with moderate calcium content that is obtained from the production of ferronickel in a blast furnace. The reaction mechanism, engineering properties, and leaching behaviors of alkali-activated BFFS materials were investigated. The results show that the main crystalline phase of the reaction products is stratlingite, and the gel phase is a kind of C-A-S-H with Ca/Si and Al/Si ratios of 0.64-1.65 and 0.57-1.44, respectively. The reaction of BFFS greatly depends on the alkalinity and silicon modulus, with a high alkalinity and low silicon modulus resulting in a rapid initial exothermic rate, a high reaction degree, and a denser pore structure in the alkali-activated BFFS materials. In addition, the compressive strength of the alkali-activated BFFS mortar is comparable to that of the alkali-activated blast furnace slag (BE); furthermore, the alkali-activated BFFS shows more continuous strength gains from 7 days to 90 days and much lower 7-day autogenous shrinkage. More importantly, the alkali-activation treatment can significantly decrease the leaching amount of Mn, Cr(VI) and Cr(III), and it converts the hazardous BFFS to non-toxic construction materials. (C) 2018 Elsevier Ltd. All rights reserved.