Sintered bayer red mud based ceramic bricks: Microstructure evolution and alkalis immobilization mechanism
Sintered bayer red mud based ceramic bricks: Microstructure evolution and alkalis immobilization mechanism
复制标题
烧结拜耳赤泥基陶瓷砖：微观结构演变和碱固定机理
DOI：
10.1016/j.ceramint.2017.07.036
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发表时间：
2017-10-15
影响因子：
5.2
通讯作者：
Luo, Shuqiong
中科院分区：
文献类型：
--
作者：
Liu, Songhui;Guan, Xuemao;Luo, Shuqiong
采用普通烧结法制备了拜耳法赤泥基陶瓷砖（RMCB），分析了烧结温度对其物理力学性能、矿物组成和显微结构的影响。分析了RMCB浸出液的水渗透性和连通孔形成机理，并通过测定浸出液的pH值和电导率评价了RMCB浸出液的环境效应。结果表明，在1125 ℃烧结时，RMCB具有优异的性能（抗压强度为22.69 MPa，体积密度为1.68 g/cm 3，总气孔率为47.12%，线收缩率为7.29%）。烧结过程中形成的霞石和钙长石相是RMCB强度的主要原因。优异的透水性归因于在RMCB内形成互连孔网络。由于在烧结过程中形成了稳定的铝硅酸盐，与原始拜耳法赤泥浸出液相比，RMCB的pH值和电导率大大降低，从而避免了碱性对环境的危害。
Bayer red mud based ceramic bricks (RMCB) were produced by normal sintering and the effects of sintering temperature on their physical and mechanical properties, mineral composition and microstructure were analyzed. The water permeability and interconnected pores formation mechanism was also analyzed, as well as the pH and conductivity of RMCB leaching solution to evaluate environmental effects. The results show the RMCB to have excellent performances (compressive strength, 22.69 MPa; bulk density, 1.68 g/cm(3); total porosity, 47.12%; Linear shrinkage, 7.29%) when sintered at 1125 degrees C. Nepheline and anorthite phases formed during sintering are felt responsible for the strength of RMCB. The excellent water permeability is attributed to the creation of a network of interconnected pores within the RMCB. The pH and conductivity of RMCB are greatly reduced compared to the raw Bayer red mud leaching solution due to the stabilized aluminosilicates formed during the sintering process, thus avoiding alkaline harm to the environment.