Influences Of Composite Grinding Aids On Grinding Efficiency And Performances Of Cement

Cement grinding aids is a group of high surface activity chemical substances, and it isused for the grinding process of cement and its mixed material. It can reduce the grindingenergy consumption of the material, improve performances of cements and improve thestrength of cement and concrete cement. The grinding aids has become one of the mostimportant energy saving technology of the cement industy. This paper made up4kind ofgrinding aids,take grinding experiment of steel slag, slag and cements which mixed with thetwo kinds of mixing materials above, use the dispersion (specific surface area,0.08mm sieveresidue and size distribution), the fluidity (Angle of repose, spherical) and the performancesof the cement as the index. The purpose is to improve the grinding efficiency of cement andits mixing materials, improve performances of cement, and reduce the cost of cementproduction. The experimental results show that:All kinds of grinding aids all can improve the grinding efficiency of steel slag and slageffectively.Specific surface area and particle concentration less than30μm of steel slag and slag areimproved; compare with the blank specimen,0.08mm sieve residue and angle of repose arereduced; the spherical of specimens increases. The grinding aids can improve the dispersionand fluidity of the material. The C agent has best grinding effect to steel slag. When itsincorporation is0.4‰, grinding time is25min, the C agent has the best effect to the steel slag.The increment of specific surface area, spherical and particle concentration less than30μmare8.6%、7.9%and30.0%respectively; the reduction of0.08mm sieve residue and angle ofrepose are44.1%and13.3%respectively. When the incorporation of A agent is0.6‰,grinding time is25min, the A agent has the best effect to the slag. The increment of specificsurface area, spherical and particle concentration less than30μm are9.2%、15.7%and26.4%respectively; the reduction of0.08mm sieve residue and angle of repose are30.4%and26.8%respectively.All kinds of grinding aids all can improve the grinding efficiency and performances ofsteel slag cement and slag cement effectively. All the stabilities of the specimens are qualified.The water demand for normal consistency of the specimens are shortly reduced; the grindingaids have no adverse effect to the setting time of all specimens. The early strength ofspecimens ncreased greatly. Through the observations on the XRD and SEM photos ofselected specimens, the ones with the grinding aids have better mineral form and high hydration degree. The D agent has the best effect to the steel slag cement. When itsincorporation is0.2‰, and the incorporation of steel slag is20%, The increment of specificsurface area, spherical and3~30μm particle concentration are4.6%、5.1%and16.1%respectively; the reduction of0.08mm sieve residue and angle of repose are38.8%and9.1%respectively; the increment of3d flexural strength and compressive strength are73.3%and18.0%.The A agent has the best effect to the slag cement. The best incorporation of grindingaids and slag are0.2‰and30%. The increment of specific surface area, spherical and3~30μm particle concentration are10.6%、13.7%and19.1%respectively; the reduction of0.08mm sieve residue and angle of repose are47.1%and26.3%respectively; the incrementof3d flexural strength and compressive strength are20.6%and21.0%...