【作者】 殷文宇； 张良苗； 包新华； 戴雨茹； 陆文聪； 陈念贻；

【Author】 Yin Wenyu, Zhang Liangmiao, Bao Xinhua, Dai Yuru, Lu Wencong, Chen Nianyi(Department of Chemistry, Shanghai University, Shanghai 200444, China)

【机构】 上海大学化学系；

【摘要】 针对萃取拜耳法铝酸钠循环液中SiO2可能积累,从而污染氢氧化铝产品的问题,查明情况并寻找对策。根据硅铝酸钠在铝酸钠- 氢氧化钠溶液中溶解度的实验数据,用模式识别算法总结出数学模型。根据数学模型推断:在萃取拜耳法整个过程中,只有蒸发前的种子分解母液和循环液萃取萃余液稀释后反回种子分解以前两个环节SiO2为过饱和状态,可能通过加硅铝酸钠晶种除硅。其余在浓缩过程中的循环液,SiO2均为饱和或未饱和。需要用添加CaCO3的方法部分除硅,使流程中硅不致积累。更多还原

【Abstract】 In order to solve the problem of the accumulation of silica in the recycling liquor in the Bayer process modified by liquid-liquid extraction, mathematical modeling for the solubility of sodium aluminum silicate was obtained by data mining of the experimental data using PLS algorithm. It is concluded that there are only two steps in the recycling process that SiO2 is oversaturated and is feasible for desilication by precipitation. Based on this conclusion, two unit processes for desilication were designed and tested. One is to add red mud as seeding to make sodium aluminum silicate precipitated. The other is to make a part of silica to form hydrogarnet precipitate by adding a small amount of calcium carbonate.更多还原