预热工艺对赤泥陶粒烧成特性及性能的影响

Influence of preheating process on the sintering characteristics and properties of red mud ceramsite

采用烘干炉-预热炉-烧成炉“三炉联用”模拟烧结机生产陶粒的方式,研究了适宜于赤泥陶粒生产的预热温度和预热时间,重点研究不同预热温度和保温时间对赤泥陶粒宏、微观形貌结构及强度、吸水率、堆积密度等基本物理、力学性能的影响。研究结果表明,优化的预热温度为550℃、预热时间15 min,且在焙烧温度1115℃、焙烧时间15 min的条件下制备的赤泥陶粒,其整体陶质化特征显著,表面粗糙,表层呈典型玻化特征,内部孔隙均布;赤泥陶粒的单粒强度达1.63 MPa、孔隙率41.9%、吸水率15.7%、堆积密度731 kg/m^(3)。

In this paper,the ceramsites were produced by simulating sintering machine which constituted through three furnaces of"drying furnace,preheating furnace and sintering furnace".The preheating temperature and preheating time suitable for producing red mud ceramsites were studied,with the focus placed on the influence of preheating temperature and time which were exerted on the basic physical and mechanical properties of red mud ceramsites(such as macro morphology,microstructure,strength,water absorption and bulk density).The results showed that the optimized preheating temperature was 550℃and the preheating time was 15 min.The ceramsites had remarkable ceramic character and rough surface when the red mud ceramsites were sintered under 1,115℃for 15 min.The surface layer of the ceramsites showed typical vitrification characteristics,with uniformly-distributed internal pores.The strength of single grain of red mud ceramsites reached 1.63 MPa,the porosity 41.9%,the water absorption 15.7%and the bulk density 731 kg/m^(3).