精炼渣基矿山充填胶凝材料制备及水化机理

Preparation and Hydration Mechanism of Refining Slag-based Mine Filling Cementitious Material

精炼钢渣(精炼渣)大量堆存污染环境,利用其开发矿山充填胶凝材料,不仅可以解决精炼渣大量堆存造成的环境污染问题,而且可以降低矿山充填成本。以精炼渣、矿渣、脱硫石膏为原材料制备三元无水泥矿山充填用胶凝材料,研究了精炼渣掺量对充填试块力学性能的影响,通过XRD、TG-DTG、IR、SEM等表征手段研究了胶凝材料的水化过程和水化机理。结果表明:胶凝材料配比为精炼渣占30%、矿渣占46%和脱硫石膏占24%时,充填试块28 d龄期抗压强度为7.35 MPa,是同条件下水泥充填试块的1.52倍;精炼渣-矿渣-脱硫石膏胶凝材料的水化产物主要为针棒状钙矾石和C—S—H凝胶,随着养护龄期的延长,水化产物不断生成,使得充填体形成具有致密结构的浆体,为硬化浆体提供强度。利用精炼渣协同矿渣和脱硫石膏制备矿山充填胶凝材料符合低碳无废发展、保护和改善环境、提高固废利用率的要求,具有广阔的市场应用前景。

Refined steel slag(RS)is stacked in large quantities and pollutes the environment.The use of RS to develop mine filling cementitious materials can not only solve the problem of large quantities of RS and pollute the environment,but also reduce the cost of mine filling.RS,blast furnace slag,and desulfurization gypsum were used as raw materials to prepare ternary cement-free mine filling cementing materials.The effect of the content of RS on the mechanical properties of the filling test block was studied.Hydration process and hydration mechanism of the cementitious material were studied through XRD,TGDTG,IR,and SEM.Results show that by mixing 30%refining slag,46%blast furnace slag,and 24%desulfurization gypsum,the 28-day compressive strength of the filled test block was 7.35 MPa,which is 1.52 times that of the cement filled test block under the same conditions.The main hydration products of the cementitious material are needle-shaped ettringite and C—S—H gel.With the extension of the curing period,hydration products are continuously generated,so that the filling body forms a slurry with a dense structure and provides strength for hardened slurry.The preparation of mine filling cementitious materials with RS,blast furnace slag and desulfurization gypsum meets the requirements of low-carbon and waste-free development,protecting and improving the environment and improving the utilization rate of solid waste,and has a broad market application prospect.