水泥助磨剂助磨性能的表征方法研究

比表面积是水泥细度常用的表征方法之一,但其是否适合评价助磨剂的助磨性能有待商榷。选用了四种助磨剂进行了粉磨实验,分别测量了被粉磨水泥的负压筛余量、颗粒分布和比表面积。对比发现:各助磨剂都对水泥的负压筛余量和颗粒分布有规律性的影响,表现为负压筛余量变小,颗粒分布变窄,但比表面积没有表现出规律性的变化。根据透气法比表面积测量原理,分析了助磨剂对比表面积没有规律性影响的原因是:添加助磨剂后,空气流过速度增大和颗粒分布变窄。不建议采用比表面积作为助磨剂性能的表征方法。

Specific surface area is one of the commonly used methods to characterize the fineness of cement,but whether it is suitable for evaluating the performance of grinding AIDS remains to be discussed.Four kinds of grinding aids were selected to carry out grinding experiments.The negative pressure screen allowance,particle distribution and specific surface area of the grinding cement were measured respectively.It was found that all grinding aids had regular effects on the negative pressure screen allowance and particle distribution of cement,which showed that the negative pressure screen allowance decreased and the particle distribution narrowed,but the specific surface area did not show regular changes.According to the measurement principle of specific surface area of air permeability method,the reasons for the irregular effect of grinding aids on the relative surface area are analyzed.After adding grinding aids,the air flow velocity increases and the particle distribution narrates.It is not recommended to use specific surface area as a characterization method for the properties of grinding aids.