Preparation of high belite silicate cement clinker with low grade limeston and its activation enhancement research
GAO Zeyu
TIAN Dongxiao
LIU Yao
YANG Caijie
MA Ying
Abstract：Belite silicate cement was prepared by partially replacing high-quality limestone with low-grade limestone.The high-temperature,high-activity crystalline form of the belite mineral phase in cement clinker was stabilized by ionic doping modi-fication.The composition of the cement mineral phase was analyzed using the X-ray diffraction(XRD)-Rietveld refinement method,and studying the hydration products and compressive strength of the cement.The results showed that the decomposition temperature of low-grade limestone is lower than that of high-quality limestone.Belite silicate cement prepared with a ratio of 1∶2 between low-grade and high-quality limestone,with clinker mineral phases of C3S,C2S,C3A,and C4AF,and f-CaO content ranging from 0.8％to 1.2％;Doping BaCO3,B2O3,MnO,and P2O5 all have a certain activating effect on C2S,which can promote the formation of α-C2S and improve hydration activity.When 0.6％B2O3 is added,the activation effect is better.The compressive strength of cement doped with 2.5％BaCO3 at 3 and 28 days increased by 12.3 and 8.7 MPa,respectively,compared to the control group without ion dop-ing;The development of mechanical strength is promoted by the ettringite(AFt)and hydrated calcium silicate(C-S-H)gel gener-ated from the hydration of Belite Portland cement.
Keywords：high belite silicate cementlow grade limestoneactivation of beliteion doping
Publication Date：2024-10-25
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 22-26 )