水泥基活化锂云母渣的硬化与盐析机理  

Mechanism of Hydration and Salting-Out of Cement-Based Activated Lepidolite Slag

作　　者：黄明夫 施麟芸 陈忠发 Huang Mingfu;Shi Linyun;Chen Zhongfa(Jiangxi Building Materials Industry Research and Design Institute,Nanchang,Jiangxi 330001)

机构地区：[1]江西省建材科研设计院有限公司,江西南昌330001

出　　处：《非金属矿》2024年第4期85-89,共5页Non-Metallic Mines

基　　金：江西省重点研发计划(20214BBG74002)。

摘　　要：本试验以水泥基活化锂云母渣硬化过程发生盐析为出发点,采用机械活化、化学激发及不同湿度养护,研究试块的盐析物相、产物类型和微观形貌,通过X射线衍射(XRD)、扫描电镜(SEM)、电感耦合等离子体质谱(ICP-MS)等分析方法探究锂渣在水硬固化过程中的反应和盐析行为。结果表明,Ca(OH)_(2)、Na_(2)SiO_(3)碱激发锂渣可分别提高锂渣1和锂渣2硬化力学性能,机械活化效果优于化学活化,活化锂渣与10%水泥胶结硬化7 d、28 d,湿养强度可达到12.3 MPa和16.4 MPa。然而,碱激发会导致锂渣中的硫铝酸盐矿物分解,可溶盐的浓度增加,发生盐析现象。湿养护促进了碱激发锂渣的离子迁移和扩散,是锂渣中石膏相纤维化长毛和发生盐析的必要条件。机械活化优化了锂渣的孔结构和比表面积,可有效预防锂渣的盐析并增加力学性能。Taking cement-based activated lithium slag salt precipitation as the starting point,mechanical activation,chemical activation,and different humidity curing were used to study the specimen’s salting-out phenomenon,product types,and microscopic morphology by XRD,SEM and ICP-MS.The results show that calcium hydroxide and sodium silicate could improve the hardened mechanical properties of lithium slag 1 and lithium slag 2,respectively.The mechanical activation effect was better than chemical activation,and the strength of activated lithium slag with 10%cement can reach 12.3 MPa and 16.4 MPa at 7 d and 28 d in wet curing.However,alkali excitation led to the decomposition of sulfoaluminate minerals in the lithium slag,which increased the concentration of soluble salt to promote the occurrence of salting-out.The humidity condition promotes the ionic migration and diffusion of alkaline-excited lithium slag,which is a necessary condition for the lithium slag gypsum phase to become fibrous and hairy and the occurrence of salting-out.Mechanical activation optimizes the pore structure and specific surface area of lithium slag,which can effectively prevent lithium slag salting-out and increase mechanical properties.

关 键 词：锂云母渣 盐析 碱激发 机械活化 水化作用 机理 

分 类 号：TU528[建筑科学—建筑技术科学] X75[环境科学与工程—环境工程]