铝酸钠溶液中水合硅酸钙的形成条件  

Formation of Calcium Silicate Hydrate in Aluminate Solution Desilication

作　　者：刘桂华[1] 孟芸[1] 李小斌[1] 彭志宏[1] 周秋生[1] 赵东峰[2] 

机构地区：[1]中南大学冶金科学与工程学院,长沙410083 [2]中国铝业股份有限公司中州分公司,河南焦作454174

出　　处：《有色金属》2004年第3期57-59,97,共4页Nonferrous Metals

基　　金：国家自然科学基金资助项目 ( 5 0 2 740 76);国家重点基础研究发展规划项目 (G19990 64 910 )

摘　　要：针对铝酸钠溶液除硅过程 ,研究苛性比、碱浓度、配钙量、温度等对水合硅酸钙形成的影响规律。结果表明 ,在常压下除硅 ,难以形成水合硅酸钙。在高温下除硅 ,苛性比增大或碱浓度降低有利于水合硅酸钙的形成。合适的配钙量为CaO/SiO2分子比 1 5左右。当CaO/SiO2 =1时 ,除硅渣主要物相是水合硅酸钙 6CaO·6SiO2 ·H2 O和 3CaO·3SiO2 ·H2 O ,而当CaO/SiO2 为 2时 ,还有 2CaO·SiO2 ·2～ 4H2 O生成。In the desilication of aluminate solution, the effects of ratio of soda to alumina, caustic concentration, lime dosage, reaction temperature and retention time on the formation of calcium silicate are investigated. The results indicate that the formation of calcium silicate hydrate is difficult at normal pressure. The increase of ratio of soda to alumina or decrease of caustic concentration is favorite to the formation of calcium silicate hydrate at high temperature. The suitable dosage of lime is to maintain CaO/SiO 2 about 1.5 in moles. The dominant composition is 6CaO·6SiO 2·H 2O and 3CaO·3SiO 2·H 2O in sediments while CaO/SiO 2=1,and a few of 2CaO·SiO 2·2～4H 2O also appears in sediment while CaO/SiO 2=2.

关 键 词：冶金技术 铝酸钠溶液 除硅 水合硅酸钙 氧化铝 

分 类 号：TF821[冶金工程—有色金属冶金]