The Black Steel slag (Ss) and phosphogypsum (PG) are industrial wastes produced in Morocco. In order to reduce these two wastes and to evaluate their pozzolanic reactivity in the presence of water, they were incorporated into bentonite (B) mixed with lime (L). The studied mixtures (BLW, BL–PG–W and BL–PG–Ss–W) were analyzed by X-ray diffraction, Infrared spectroscopy, Raman spectroscopy and SEM/EDX analysis. Compressive strength tests were performed on hardened specimens. The results obtained show that the hydration kinetics of the B–L–W and B–L–PG–W mixtures are slow. The addition of PG to a bentonite––lime mixture induces the formation of new microstructures such as hydrated calcium silicate (C–S–H) and ettringite, which increases the compressive strength of the cementitious specimens. The addition of the Ss to a mixture composed of 8%PG and 8%L–B accelerates the kinetics of hydration and activates the pozzolanic reaction. The presence of C₂S in the slag helps to increase the mechanical strength of the mixture B–L–PG–Ss. The compressive strength of the mixtures BL–W, BL–PG–W and BL–PG–Ss–W increases from 15 to 28 days of setting. After 28 days of setting, 8% of Sc added to the mixture 8% PG–8%L–B is responsible for an increase of the compressive strength to 0.6 MPa.

中文翻译：

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磷石膏和黑钢渣作为生态膨润土基材料的添加剂：微观结构和表征

黑钢渣（Ss）和磷石膏（PG）是摩洛哥生产的工业废料。为了减少这两种废物并评估它们在水的存在下的火山灰反应性，将它们掺入与石灰（L）混合的膨润土（B）中。通过X射线衍射，红外光谱，拉曼光谱和SEM / EDX分析对所研究的混合物（BLW，BL–PG–W和BL–PG–Ss–W）进行分析。在硬化样品上进行抗压强度测试。获得的结果表明，B–L–W和B–L–PG–W混合物的水合动力学很慢。在膨润土-石灰混合物中添加PG会诱导新的微观结构的形成，例如水合硅酸钙（CS-H）和钙矾石，从而增加了水泥样品的抗压强度。在由8％PG和8％L–B组成的混合物中添加Ss可以加速水合动力学并激活火山灰反应。C的存在炉渣中的₂ S有助于提高B–L–PG–Ss混合物的机械强度。BL–W，BL–PG–W和BL–PG–Ss–W混合物的抗压强度从凝固的15天增加到28天。凝固28天后，向8％PG–8％L–B混合物中添加8％的Sc可使抗压强度提高到0.6 MPa。