甲酸干法化学改性钢渣粉及其浆体性能研究

探明化学改性钢渣粉的活性和力学性能对提升钢渣利用具有重要意义。研究选取4种钢渣粉采用4 % 的甲酸溶液进行干法化学改性，采用背散射电子显微镜、水化量热仪、X射线衍射仪、傅里叶变换红外光谱仪表征了改性前后钢渣粉及其浆体性能的变化。结果发现，不同钢渣粉矿物组成差异较大，制备的浆体3 d和7 d抗压强度均较低，72 h的水化热在10~40 J/g间波动；但经过甲酸改性后，其3 d抗压强度提升率都超过200 %，72 h水化热均提升至50 J/g以上，提升率均超过80 %，钢渣粉中的Ca(OH)₂均能参与反应并生成甲酸钙，而其中的活性硅酸盐未受到显著影响。

Investigating the performance of dry chemically modified steel slag powder and pastes by formic acid

Understanding the composition and reactivity of formic acid modified steel slag powder (SS) from micro scale is critical to extending the utilization of steel slag. In this study, four representative sources of SS were selected, which were dry chemically modified by formic acid (FA) with a mass fraction of 4 % on the basis of SS. The backscatter electron microscope, hydration calorimeter, X-ray diffractometer and fourier transform infrared spectrometer were applied to characterize the SS and SS pastes before and after modification. Results show that the 3 d and 7 d compressive strength of the different sources of SS pastes are low, and the 72 h cumulative hydration heat varies between 10~40 J/g due to their different mineral compositions. However, after FC modification, the 3 d compressive strength increases by more than 200 %, and the 72 h cumulative hydration heat rises to above 50 J/g with an increase above 80 %.it is found that the Ca(OH)₂ in SS can react with FA to produce calcium formate, while the calcium silicates in SS are not significantly affected.