复合转晶剂对建筑石膏性能的影响  

Effects of Composite Crystal Modifiers on Properties of Calcined Gypsum

作　　者：郝建英[1] 王升昌 陈佳宁 田博 HAO Jianying;WANG Shengchang;CHEN Jianing;TIAN Bo(School of Materials Science and Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,China)

机构地区：[1]太原科技大学材料科学与工程学院,太原030024

出　　处：《硅酸盐通报》2023年第11期4027-4034,共8页Bulletin of the Chinese Ceramic Society

基　　金：山西省基础研究计划(202203021211186);太原科技大学研究生教育创新项目(SY2022002)。

摘　　要：脱硫石膏(FGD gypsum)作为一种固废,可经过高温煅烧制备建筑石膏,实现固废资源化利用。以脱硫石膏为原料,氧化钙和硫酸铝为复合转晶剂,在170℃下煅烧2 h制备建筑石膏,研究复合转晶剂的复合比例及掺量对建筑石膏力学性能的影响,并揭示其复合转晶机理。结果表明,当复合转晶剂掺量为1%(质量分数)、氧化钙和硫酸铝复合比例为1∶1(质量比)时,制备的建筑石膏力学性能最佳。水化后石膏块体致密性良好,水化产物呈相互交错的短柱状或纤维状。建筑石膏的2 h抗折和抗压强度分别为3.6和9.7 MPa,绝干抗折和抗压强度分别为6.8和23.5 MPa,满足《建筑石膏》(GB/T 9776—2022)中3.0级建筑石膏的要求。As a kind of solid waste,flue gas desulfurization(FGD)gypsum can be used to prepare calcined gypsum by calcining at high temperature to realize the resource utilization of solid waste.FGD gypsum was used as raw material,calcium oxide and aluminum sulfate were added as composite crystal modifiers,and calcined gypsum was prepared by calcining at 170℃for 2 h.The effects of the composite ratio and dosage of composite crystal modifiers on the properties of calcined gypsum were studied,and the composite crystal conversion mechanism was revealed.The results show that when the content of composite crystal modifier is 1%(mass fraction)and the composite ratio of calcium oxide and aluminum sulfate is 1∶1(mass ratio),the prepared calcined gypsum has the best property.The gypsum block is dense after hydration,and the hydration products are in the form of alternating short columns or fibers.The 2 h flexural and compressive strength of calcined gypsum are 3.6 and 9.7 MPa,the dry flexural and compressive strength are 6.8 and 23.5 MPa,which meets the requirements of grade 3.0 calcined gypsum in Calcined Gypsum(GB/T 9776—2022).

关 键 词：脱硫石膏 建筑石膏 复合转晶剂 硫酸铝 氧化钙 力学性能 

分 类 号：TU528[建筑科学—建筑技术科学]