CO2体积分数对碱激发镍渣水泥砂浆抗碳化性能的影响

Effect of CO2 Volume Fraction on Carbonation Resistance of Alkali-Activated Nickel Slag Cement Mortar

关键词:  碱激发水泥  镍渣  碳化  CO₂体积分数  碱激发剂种类

Key words:  alkali-activated cement  nickel slag  carbonation  CO₂ volume fraction  alkali activator type

摘要:

利用机械化学方法制备了单组分碱激发镍渣水泥，分析了CO₂体积分数对不同碱激发剂制备的单组分碱激发镍渣水泥砂浆抗碳化性能的影响规律，结合孔结构分析、X射线衍射（XRD）分析等研究了其作用机理.结果表明：水泥砂浆的碳化产物与碱激发剂种类无关，与CO₂体积分数有关.在CO₂体积分数为3%条件下进行试验，水泥砂浆的碳化产物为碳酸盐产物，且碳化速率远低于CO₂体积分数为10%与20%的试验组；而在CO₂体积分数为10%与20%条件下进行试验，水泥砂浆的碳化产物为碳酸盐与碳酸氢盐.碳酸盐对孔隙填充效果优于碳酸氢盐，因此CO₂体积分数为3%时砂浆碳化后的孔结构、抗压强度均优于其体积分数为10%与20%时.

Abstract:

One-part alkali-activated nickel slag cement was prepared by mechanochemical method. The carbonation resistance of one-part alkali-activated nickel slag cement mortar prepared with different alkali activators were tested， to study the effect of CO₂ volume fraction on the carbonation resistance of one-part alkali-activated nickel slag cement mortar. The mechanism was analyzed by pore structure analysis and X-ray diffraction（XRD） analysis. The results show that the carbonation products of the cement mortar are not related to the type of alkali activator， but to the CO₂ volume fraction. The carbonation products of the cement mortar tested at 3% CO₂ volume fraction are carbonation products， and the carbonation rate is much lower than that at 10% and 20% CO₂ volume fractions. The carbonation products of the cement mortar tested at 10% and 20% CO₂ volume fractions are carbonate and bicarbonate products. The carbonate is better than bicarbonate in pore filling， so the pore structure and compressive strength of the mortar after carbonation at 3% CO₂ volume fraction is better than those at 10% and 20% CO₂ volume fractions.