锂渣细度对掺减水剂的水泥浆体流变性能的影响

Effect of Lithium Slag Fineness on Rheological Properties of Cement Paste Mixed with Superplasticizers

随着锂盐工业的迅猛发展,锂渣堆存量逐年增加,将其磨细后作为矿物掺合料进行资源化利用可有效解决这一问题。本工作采用流动度及经时损失、流变参数、Zeta电位等测试手段表征了锂渣细度对掺减水剂的水泥浆体流变性能的影响。结果表明:锂渣掺量为15%时,体系初始屈服应力和塑性黏度均随锂渣比表面积的增大而增大,宏观表现为体系的初始流动度随锂渣比表面积的增大而减小;掺锂渣体系的流动度60 min后开始下降,且下降程度随锂渣比表面积的增大而增大,相比于纯水泥体系,掺入锂渣后浆体流动度经时损失有大幅改善。掺入锂渣后体系初始Zeta电位下降明显,5~60 min降幅逐渐变小,60 min后趋于稳定。对于不同细度锂渣,体系Zeta电位随着比表面积的增大而降低。

With the rapid development of lithium salt industry,the storage of lithium slag has been increasing year by year.Using the ground lithium slag as a mineral admixture in concrete can effectively solve the stock problem.In this study,fluidity and fluidity loss over time,rheological parameters,Zeta potential were measured to investigate the effect of lithium slag fineness on the rheological properties of cement paste with superplasticizers.The results showed that when the content of lithium slag was constant(i.e.,15%),the initial yield stress and plastic viscosity of the system increased with the increase of specific surface area of lithium slag,and the initial fluidity of the system decreased with the increase of specific surface area of lithium slag.The fluidities of all the systems with and without lithium slag began to decrease after 60 minutes,and the fluidity loss grew with the increase of the specific surface area of lithium slag.Compared to the pure cement system,fluidity losses of three systems with lithium slag were much smaller.The initial Zeta potential of systems with lithium slag decreased obviously,and the decline diminished gradually within 60 minutes and tended to be stable after 60 minutes.The Zeta potential of systems incorporating lithium slags with different finenesses decreased with the increase of specific surface area of lithium slag.