石灰碱激发钛石膏复合胶凝材料强度机理分析  

Analysis of the strength mechanism of lime-base activated titanium gypsum composite cementitious material

作　　者：杨贺 Yang He(China Railway Tunnel Stock Co.,Ltd.,Zhengzhou 450001,Henan,China;School of Civil Engineering,Architecture and Environment,Xihua University,Chengdu 610039,Sichuan,China)

机构地区：[1]中铁隧道股份有限公司,河南郑州450001 [2]西华大学土木建筑与环境学院,四川成都610039

出　　处：《钢铁钒钛》2021年第3期111-118,共8页Iron Steel Vanadium Titanium

基　　金：四川省高等学校重点实验室重点项目(工业固态废弃物土木工程综合开发利用SC-FQWLY-2019-Z-01)。

摘　　要：以钛石膏、脱硫石膏和钛矿渣三种钛工业固体废弃物为主要原料,石灰作碱性激发剂制作钛石膏复合胶凝材料。采用正交试验,结合XRD、SEM等分析测试方法,对石灰碱激发钛石膏复合胶凝材料强度机理进行分析。结果表明:钛石膏的掺量在42.9%~50.3%,可以制作出强度达到《建筑石膏》(GB/T 9776—2008)2.0强度等级的钛石膏复合胶凝材料。石灰碱激发钛石膏复合胶凝材料的前期强度主要来自钛石膏和脱硫石膏水化产生的二水石膏,后期强度主要来自水泥、石灰和石膏进一步反应产生钙矾石。其水化机理为:第一,CaSO_(4)·0.5H_(2)O水化产生CaSO_(4)·2H_(2)O;第二,水泥中的3CaO·Al_(2)O_(3)与CaSO_(4)·2H_(2)O反应生成钙矾石,石灰与水反应产生Ca(OH)2,结合CaSO_(4)·2H_(2)O和CaO·Al_(2)O_(3)反应产生钙矾石,进一步提升钛石膏复合胶凝材料的强度。Titanium gypsum,flue gas desulphurization gypsum and titanium slag are used as main raw materials of titanium industrial solid wastes,and lime is used as an alkaline activator to make titanium gypsum composite cementing materials.Orthogonal experiments,combined with XRD,SEM and other analytical testing methods,are used to analyze the strength mechanism of lime-base activated titanium gypsum composite cementing materials.The experimental results show that the content of titanium gypsum is between 42.9%and 50.3%,which can produce a titanium gypsum composite cementing material with strength of 2.0 in"Building Gypsum"(GB/T 9776—2008).The initial strength contribution of the lime-based titanium gypsum composite cementing material mainly comes from the dihydrate gypsum produced by the hydration of titanium gypsum and flue gas desulphurization gypsum,and the later strength contribution mainly comes from the further reaction of cement,lime and gypsum to produce ettringite.The hydration mechanism is as follows:First,CaSO_(4)·0.5H_(2)O hydrates to produce CaSO_(4)·2H_(2)O;Second,the 3CaO·Al_(2)O_(3) in the cement reacts with CaSO_(4)·2H_(2)O to produce ettringite,the lime reacts with water to produce Ca(OH)2,and the combination of CaSO_(4)·2H_(2)O and CaO·Al_(2)O_(3) react to produce ettringite.Therefore,the strength of the titanium gypsum composite cementitious material is further improved.

关 键 词：钛石膏 脱硫石膏 钛矿渣粉 钛工业固废 复合胶凝材料 强度机理 

分 类 号：TF823[冶金工程—有色金属冶金] X757[环境科学与工程—环境工程]