改变拜耳法预脱硅工艺降低赤泥化学结合碱的研究  

A study on modification of predesilication in Bayer process for reducing bound soda in red mud

作　　者：陈文汨[1] 彭秋燕[1] 黄伟光[1] 李云峰[1] 

机构地区：[1]中南大学冶金科学与工程学院,湖南长沙410083

出　　处：《轻金属》2010年第6期7-10,17,共5页Light Metals

摘　　要：研究了拜耳法预脱硅工艺,目的在于降低赤泥化学结合碱。在预脱硅段使用低碱、高ak溶液(沉铝液)对铝土矿进行脱硅,然后补进浓缩的循环母液溶出铝土矿,使铝土矿中的含硅矿物更多地转化为水化石榴石形态,达到降低赤泥化学结合碱的目的。实验研究发现,当预脱硅温度为160℃,反应时间为120min,沉铝液碱含量为15%,ak为30.8,配矿C/S比为1.3,溶出温度为260℃,反应时间为60min时,采用本方法溶出河南某地铝土矿产生的赤泥N/S从常规溶出赤泥N/S的0.42降为0.23。In this paper a study was conducted on modification of predesilication in the Bayer process to reduce bound soda in red mud. Bauxite is desilicated with high ak and low caustic concentration liquor, and then is digested with concentrated Bayer spent liquor. The purpose is to reduce bound soda of red mud by transforming more silica-containing mineral into hydrogarnet instead of sodium alumino-silicate hydrate. The results showed that when the Henan bauxite was desilicated at 160℃ for 120 min with the high ak...

关 键 词：化学结合碱 碱耗 预脱硅 水化石榴石 拜耳法 

分 类 号：TF821[冶金工程—有色金属冶金]