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⁻.

这项研究集中于不同CaSO ₄含量的NaOH活化炉渣的反应和初始设定。首先研究宏观性质，然后使用微反应器方法并结合放热速率，元素浓度和沉淀物的半定量来监测反应过程。结果证明存在适当的剂量的CaSO ₄作为缓凝剂（具体而言，本研究中为4 wt％）。低于该值，CaSO ₄不会阻碍反应；高于该值，将显着延迟，但抗压强度也会大大损失。阻滞作用主要归因于高Ca ²⁺浓度的抑制（从CaSO ₄溶解）而不是降低pH值或SO ₄ ^2-的影响。