New insights into the early reaction of NaOH-activated slag in the presence of CaSO4
New insights into the early reaction of NaOH-activated slag in the presence of CaSO4
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对 NaOH 活化渣在 CaSO4 存在下的早期反应的新见解
DOI：
10.1016/j.compositesb.2020.108207
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发表时间：
2020-10-01
影响因子：
13.1
通讯作者：
Huang, Zongxian
中科院分区：
文献类型：
--
作者：
Wang, Dengquan;Wang, Qiang;Huang, Zongxian
研究了不同CaSO 4含量的NaOH激发渣的反应和初凝情况。首先研究了宏观性质，然后采用微反应器法，结合放热速率、元素浓度和半定量相结合的方法对反应过程进行了监测。结果表明，CaSO 4作为缓凝剂存在一个合适的掺量（本研究中具体为4wt%）。低于该值时，CaSO 4不会阻碍反应;高于该值时，会有显著的阻碍，但抗压强度也会有很大的损失。这种延迟主要是由于高浓度的Ca 2+（从CaSO 4中溶解出来）对炉渣溶解的抑制作用，而不是由于pH值的降低或SO 42-的影响。
This study focused on the reaction and initial setting of NaOH-activated slag with different CaSO4 contents. The macroscopic properties were firstly investigated, and then the reaction process was monitored using a micro-reactor method and a combination of exothermic rate, element concentration and semi-quantification of precipitates. The results prove that there is a proper dosage for CaSO4 as a retarder (specifically, 4 wt% in this study). Below this value, CaSO4 does not retard the reaction; above this value, there is a significant retardation, but also a great loss in compressive strength. The retardation is mainly attributed to the inhibition of high Ca2+ concentration (dissolved from CaSO4) on the slag dissolution, rather than the decreased pH or the effect of SO42-.