钛石膏-脱硫石膏复合胶凝材料力学性能研究

Study on Mechanical Properties of Titanium Gypsum-FGD Composite Cementitious Materials

将钛石膏和脱硫石膏两种工业固体废弃物综合利用,制备钛石膏-脱硫石膏(简称:TG-FGD)复合胶凝材料。利用Origin软件对TG-FGD复合胶凝材料抗折强度与抗压强度数据进行非线性拟合,得到相关度较高的拟合曲线与强度关系式。结合XRD、SEM等测试方法分析TG-FGD复合胶凝材料反应物相和微观形貌。结果表明:随着脱硫石膏掺量的增加,TG-FGD复合胶凝材料2 h抗折与抗压强度均增大;钛石膏与脱硫石膏按质量3∶2制作TG-FGD复合胶凝材料,石膏增强剂(主成分为聚羧酸醚)的适宜掺量为0.05%,达到GB/T 9776-2008《建筑石膏》1.6等级,复合胶凝材料的强度提高10%左右;掺加石膏增强剂降低了水膏比,且水化产生的二水石膏晶体排列较为紧凑,有利于TG-FGD复合胶凝材料形成较高强度。

The titanium gypsum-flue gas desulphurization gypsum(abbreviation:TG-FGD)composite cementing material is prepared by comprehensively utilizing two industrial solid wastes of titanium gypsum and flue gas desulphurization gypsum.The nonlinear fitting of the TG-FGD composite cementitious material’s flexural and compressive data was carried out by Origin software,and the relationship between the fitting curve and the intensity with high correlation was obtained.The phase and micromorphology of TG-FGD composite cementitious materials were analyzed by XRD and SEM.The results show that the flexural strength and compressive strength of TG-FGD composite cementing material increase with the increase of FGD content.Titanium gypsum and FGD are made of TG-FGD composite cementitious material according to the mass of 3:2.The suitable dosage of gypsum enhancer agent(main component is polycarboxylate ether)is 0.05%,reaching"Building Gypsum"(GB/T 9776-2008)grade 1.6,the strength of the composite cementitious material is increased by about 10%.The addition of gypsum enhancer reduces the water paste ratio,and the crystal structure of the dihydrate gypsum produced by hydration is relatively compact,which is favorable for the formation of high strength of the TG-FGD composite cementitious material.