(1. 中南大学 冶金与环境学院，长沙 410083;
2. 中国铝业股份有限公司广西分公司，平果 531400)
摘 要: 通过测定接触角、X射线衍射谱和元素含量，研究预热套管结疤组成和表面性质间的关系。结果表明:随着预热温度升高，结疤相中碱(Na2O)、二氧化硅、氧化铝和磷含量随之升高，氧化镁、二氧化钛、灼减量逐渐减少，氧化钙含量变化不明显;钛酸钙量减少，钠硅渣、水化石榴石量增多，且水化石榴石中二氧化硅系数增大，结疤的硬度增强;由于钠硅渣、水化石榴石、赤铁矿比钛酸钙的亲水性强，随着温度的升高，套管结疤的亲水性增强，疏水性减弱，因而，高温下更有利于生成更致密、难清理的结疤。加入有机添加剂，可以改变渣相的表面性质，为防止结疤提供新途径。
关键字: 结疤;预热套管;表面性质;钠硅渣;钛酸钙;水化石榴石;有机添加剂
（1. School of Metallurgical and Environment, Central South University, Changsha 410083, China;
2. Guangxi Branch of Chalco, Pingguo 531400, China）
Abstract:In order to inhibit scale’s formation, the relationship between composition of scale and its surface property was investigated by the analysis of contact angle, X-ray diffraction and elemental content of scale. The results show that, with the increase of preheating temperature, the contents of alkali soda, silica, alumina and phosphorus increase, but those of magnesia, titania and igloss reduces gradually, the content of calcium oxides almost remains unchangeable. Increasing temperature raises the content of sodium hydrate alumino-silicate and hydrogarnet, but reduces the content of calcium titanate in scale. Moreover, increasing preheating temperature not only increases the stoichiometric coefficient of SiO2 in hydrogarnet, but also improves the Moh’s hardness of the scale. Because the hydrophilicities of sodium hydrate alumino-silicate, hydrogarnet and hematite are greater than that of calcium titanate, increasing temperature enhances scale’s hydrophilicity and declines scale`s hydrophobicity. Therefore, the elevated temperature is conducive to the formation of the compact scale due to the hydrophilicity of sodium hydrate alumino-silicate and hydrogarnet, leading to difficult removal of the scale. In addition, the surface properties of the scale can be changed by adding the organic additive, implying an available method to inhibit the formation of the scale.
Key words: scale; preheating pipe; surface property; sodium hydrate alumino-silicate; calcium titanate; hydrogarnet; organic additive
