Steel slag, an industrial by-product from the steelmaking process, has limited utilities primarily due to its low reactivity and grindability. This study proposed a new method to actively utilize steel slag as a cementless binder by adding glycine to enhance the reactivity of steel slag under CO curing condition. Employing glycine as an activator under 1 day of hydration followed by 7 days of carbonation curing resulted in noticeable densification of the microstructure and significant improvement in compressive strength. The compressive strength of seven-day carbonated steel slag with 3 wt% glycine reached 77.8 MPa. This improvement was due to the accelerated hydration of brownmillerite (CF) and gradual carbonation during the carbonation period. While CF was merely reactive without glycine, the hydration of CF was significantly stimulated by glycine addition, producing hydrogarnet, CO-bearing AFm phases, and amorphous phases. During the carbonation curing, AFm phases and hydrogarnet were carbonated and formed various polymorphs of CaCO and amorphous Al(OH). Adding 3 wt% and 5 wt% of glycine decreased the degree of carbonation, preserving the quantity of AFm phases and hydrogarnet. The use of glycine also made the pores finer and induced the reaction of RO phase to form pyroaurite.

中文翻译：

---

甘氨酸辅助水化和碳化固化提高钢渣的力学性能

钢渣是炼钢过程中的工业副产品，其用途有限，主要是因为其反应性和可磨性较低。本研究提出了一种积极利用钢渣作为无水泥粘结剂的新方法，通过添加甘氨酸来增强钢渣在CO固化条件下的反应活性。使用甘氨酸作为活化剂，经过 1 天的水合，然后进行 7 天的碳化固化，导致显微结构显着致密化，并显着提高了抗压强度。添加3 wt%甘氨酸的7天碳化钢渣的抗压强度达到77.8 MPa。这种改善是由于褐针石（CF）的加速水化和碳酸化期间的逐渐碳酸化所致。虽然 CF 在没有甘氨酸的情况下仅具有反应性，但甘氨酸的添加显着刺激了 CF 的水合，产生氢石榴石、含 CO 的 AFm 相和无定形相。在碳化固化过程中，AFm 相和氢石榴石被碳化并形成 CaCO 和无定形 Al(OH)2 的各种多晶型物。添加 3 wt% 和 5 wt% 的甘氨酸降低了碳酸化程度，保留了 AFm 相和氢石榴石的数量。甘氨酸的使用还使孔隙变得更细，并诱导RO相反应形成焦金矿。