Abstract: In order to explore the application feasibility of CA₆ refractories in the transition zone of cement rotary kilns,CA₆ refractories with a porosity of 27.7% were prepared and then lined in the transition zone of a 5 000 ton/day rotary kiln.After two months operation,the residual thickness of the bricks was still 180-200 mm,exhibiting good corrosion resistance.Compared with magnesium aluminate spinel bricks,the cylinder temperature lined with CA₆ reduced by 40-80 ℃,performing a significant energy-saving and thermal insulation effect.As for the damage mechanism,it is believed that although alkali metals can react with CA₆ refractories to produce KAl₁₁O₁₇,the reaction is slow,so its impact on material damage is mild;in addition to the corrosion of cement clinker,a large amount of KCl sediment is the key factor for the structural deterioration of CA₆ refractories;CA₆ refractories can be used in the transition zone of rotary kilns,but better densification is required.

Key words: CA₆ refractories, transition zone, damage mechanism, energy-saving and thermal insulation

摘要： 为探索CA₆质耐火材料在水泥回转窑过渡带上应用的可行性,制备了气孔率高达27.7%的CA₆质耐火材料,砌筑于日产5 000 t回转窑的过渡带。经过2个月的运转,残砖厚度为180~200 mm,抗侵蚀性较好,且该材料的保温效果非常显著,相比于砌筑镁铝尖晶石砖的筒体温度降低了40~80 ℃。分析其损毁机制认为:碱金属尽管可以与CA₆反应生成KAl₁₁O₁₇,但反应进程较慢,对材料损毁影响不大;CA₆质耐火材料的损毁除受到水泥物料的熔蚀外,大量沉积的KCl是导致其结构劣变的关键因素;CA₆质耐火材料可用于回转窑过渡带,但需要致密化。

关键词: CA₆质耐火材料, 过渡带, 损毁机制, 节能保温