新型低钙气硬性硅酸盐水泥的碳化机理研究

关键字：新型,低钙,气硬性,硅酸盐水泥,碳化机理

（中国建筑材料科学研究总院，绿色建筑材料国家重点实验室，北京  100024）

 
    摘要：通过高温煅烧石灰石及石英组成的混合配料制备了一种以3CaCO3·2SiO2（C3S2）为主要矿物组成的新型低钙气硬性硅酸盐水泥，研究其碳化硬化机理，着重研究该熟料矿物的形成温度、碳化硬化及强度。结果表明：C3S2 单矿的形成温度为1320~1460 ℃；新型低钙气硬性硅酸盐水泥最佳配比中应控制Al2O3含量4%、Fe2O3含量2%左右，其中Ca/Si比在1.2~1.3；最佳的煅烧形成参数为1300 ℃、保温6 h。碳化产物为CaCO3、SiO2。试样在室温条件，水固比为14%、CO2分压为0.2 MPa，碳化3 d的抗压强度达到38.5 MPa。该新型低钙气硬性硅酸盐水泥具有显著的碳吸附和低碳排放特点。
    关键词：低钙气硬性硅酸盐水泥；3CaCO3·2SiO2矿物；碳化；碳化时间；CO2分压
    中图分类号：TQ172.71+9.9；TU526      文献标识码：A      文章编号：1001-702X（2018）01-0109-05
 

Carbonation mechanism of new low-calcium air-setting portland cement
LIU Yaojun，WANG Lan
（China Building Materials Academy，State Key Laboratory of Green Building Materials，Beijing 100024，China）

    Abstract：A new low calcium air-setting cement mainly consisting of 3CaCO3·2SiO2（C3S2） mineral was prepared by the high-temperature calcination of limestone and quartz，its carbonization and hardening mechanisms were studied. The clinker formation temperature，calcination mechanism，hardening process and strength were investigated. The results show that the formation temperature of C3S2 clinker is from 1320 ℃ to 1460 ℃；this optimal low calcium air-setting cement is of 4% Al2O3 and 2% Fe2O3，1.2~1.3 of Ca/Si ratio，with the calcination mechanism is 1300 ℃ and kept for 6 h. The carbonization products are CaCO3 and SiO2，and the compressive strengths of low calcium air-setting cement samples are 38.5 MPa after carbonation at room temperature，water-solid ratio of 14%，and CO2 partial pressure of 0.2 MPa for 3 d. The low calcium cement has the features of carbon capture due to its low calcium characteristic.
    Key words：low calcium air-setting portland cement，3CaCO3·2SiO2 mineral，carbonization，carbonation time，CO2 partial pressure