碱溶—碳分法生产氧化铝溶出效果研究  

Study on Dissolution Effects of Alkali Dissolution-Carbonation Precipitation Process for Producing Alumina

作　　者：王红伟[1] 马科友[1] 张学英 董凯伟 潘晓林 WANG Hong-wei;MA Ke-you;ZHANG Xue-ying;DONG Kai-wei;PAN Xiao-lin(Metallurgical and Chemical Department,Jiyuan Vocational and Technical College,Jiyuan 459000,Henan,China;School of Metallurgy,Northeastern University,Shenyang 110819,China)

机构地区：[1]济源职业技术学院冶金化工系,河南济源459000 [2]东北大学冶金学院,沈阳110819

出　　处：《有色金属（冶炼部分）》2021年第9期41-47,共7页Nonferrous Metals（Extractive Metallurgy)

基　　金：国家自然科学基金资助项目(51104041,22078055)。

摘　　要：NaOH溶液溶出铝土矿是碱溶—碳分法生产氧化铝新工艺的核心技术之一。采用现有拜耳法生产设备进行预脱硅和高压溶出试验,研究用NaOH溶液溶出不同铝硅比(A/S)一水硬铝石型铝土矿的溶出效果,确定了适宜的工艺条件,并与生产现场拜耳法蒸发母液溶出的效果和生产效率进行了对比。结果表明,矿石的实际溶出率(η实)随矿石A/S、苛性碱质量浓度(NK)、配料分子比(αk配)和配料溶出率(η配)的升高而升高,随石灰添加量的增加呈先升后降的趋势;在相同工艺条件下,现场母液与NaOH溶液溶出的效果基本保持在相同水平,但相同体积的NaOH溶液溶出矿石量是现场蒸发母液的1.71倍,循环效率则是现场蒸发母液的2.16倍;碱溶—碳分工艺预脱硅溶出的适宜条件为:矿石A/S>4.0、预脱硅温度98℃、预脱硅时间6h、NK=200g/L、石灰添加量11%、αk配=1.3~1.5、η配=90%、溶出温度273℃、溶出时间40min,此条件下A/S=8.65矿石的η实可达87.75%。It is one of core technology for alkali dissolution-carbonation precipitation new process for producing alumina with bauxite leached by NaOH solution.Pre-desilication and high pressure digestion experiments were carried out using the existing productive equipments of Bayer process,and dissolution effects of different A/S diasporic bauxite leached by NaOH solution were investigated.The suitable technological conditions were determined,and dissolution effects and production efficiency were compared with evaporation mother liquor from Bayer process.The results show that actual digestion rate of Al2O3 dissolution rises with increase of A/S of bauxite,caustic soda mass concentration NK,proportioning molar ratioαkand digestion rate of proportioning dissolution,while actual rate of Al2O3 dissolution rises first then drops with increase of lime addition.Dissolution effects leached by NaOH solution and vaporation mother liquor from Bayer process are keeping the same level,but bauxite amount leached by NaOH solution is 1.71 times than the same volume of evaporation mother liquor from Bayer process,and cycle efficiency is 2.16 times than the same volume of evaporation mother liquor from Bayer process.Actual digestion rate of Al2O3 dissolution is 87.75%under the suitable conditions for pre-desilication and digestion of alkali dissolution-carbonation precipitation process including A/S of 8.65,pre-desilication temperature of 98℃,pre-desilication time of 6 h,NK of 200 g/L,lime addition of 11%,proportioning molar ratio of 1.3~1.5,proportioning dissolution rate of 90%,digestion temperature of 273℃,and digestion time of 40 min.

关 键 词：碱溶—碳分法 氧化铝 一水硬铝石 NAOH溶液 溶出 

分 类 号：TF821[冶金工程—有色金属冶金]