普通硅酸盐水泥广泛用于高硫尾砂的胶结充填,但因硫酸盐侵蚀会导致充填体早期强度低而后期膨胀、开裂以及强度倒缩。本研究以矿渣为主要材料辅以少量激发剂配制成KL固化剂取代水泥固化高硫尾砂,相同条件下,试样7d和60d强度是水泥试样的2.3倍和6.0倍,早期强度高,后期强度不倒缩。KL固化剂中的低碱环境使得适量钙矾石在早期形成,不破坏水化硅酸钙凝胶结构,还能充当骨架降低孔隙率使试样更密实。综上可知,与水泥相比,KL固化剂固化高硫尾砂具有更好的强度和耐久性。
Ordinary Portland cement(OPC) is extensively used for cemented paste backfill of high sulfur tailings, while the strength of specimen is low in early period and decline in later period. The appearance of specimen is expansion and crack mainly due to sulphate attack. In this study, ground granulated blast furnace slag with a few activator were prepared as alternative binder(KL stabilizer) to OPC for cemented paste backfill of high sulfur mill tailings. In the same conditions, the strengths of specimens were 2.3 and 6.0 times of OPC in 7d and 60d stage,which were higher in early period and more stable in later period. The low alkali of KL made appropriate ettringite form in initial stage, which did not damage the structure formed by calcium silicate hydrate, in the same time, the ettringite could make the specimens denser by forming skeleton and decreasing porosity. The findings have revealed that the stabilizer prepared by ground granulated blast furnace slag is superior strength and durability in cemented paste backfill of high sulfur tailings as compared with OPC.