酸碱联合综合回收高铝粉煤灰中氧化铝和氧化硅  

Recovery of Alumina and Silicon Oxide from High-alumina Fly Ash by Acid and Alkali Combination Method

作　　者：蒋训雄 蒋开喜 汪胜东 李达 JIANG Xun-xiong;JIANG Kai-xi;WANG Sheng-dong;LI Da(BGRIMM Technology Group,Beijing 100160,China)

机构地区：[1]北京矿冶科技集团有限公司

出　　处：《有色金属（冶炼部分）》2019年第9期28-32,44,共6页Nonferrous Metals（Extractive Metallurgy)

基　　金：北京矿冶研究总院科研基金项目(02-1502)

摘　　要：以高铝粉煤灰为原料,采用酸碱联合的方法从粉煤灰中综合回收氧化铝及氧化硅,即:粉煤灰经过浓硫酸熟化—水浸提取氧化铝,并得到活性高硅渣;硫酸铝溶液经浓缩结晶—还原焙烧得到活性铝氧;活性铝氧经低温碱浸—种分得到砂状氧化铝;活性高硅渣经低温碱浸提取氧化硅。结果表明,采用该工艺,粉煤灰中氧化铝熟化—水浸的氧化铝提取率为94.97%;硫酸铝800℃还原焙烧10min,获得的粗铝氧中Al2O3含量为85.58%、残余S含量0.53%;在95℃碱浸,粗铝氧中氧化铝的浸出率为97.36%;在95℃碱浸,高硅渣的硅浸出率96.25%。Comprehensive recovery of alumina and silicon oxide from high-alumina fly ash by acid and alkali combination method was studied.After fly ash was cured with concentrated sulfuric acid,94.97%of aluminum oxide was extracted by water leaching,and active high silicon slag was obtained.Aluminum-containing solution was concentrated and crystallized to obtain aluminum sulfate.Crude active alumina was obtained from aluminum sulfate by reduction roasting at 800℃for 10 min,which contains 85.58%Al 2O 3 and 0.53%S.Sandy alumina was prepared from crude active alumina by low temperature alkaline leaching and seeded precipitation.Silica oxide was extracted from high silicon slag by low temperature alkaline leaching.Leaching rate of aluminum oxide in crude alumina is 97.36%by alkali leaching at 95℃;silicon leaching rate of high silicon slag is 96.25%by alkali leaching at 95℃.

关 键 词：粉煤灰 氧化铝 氧化硅 综合回收 酸碱联合法 硫酸熟化 

分 类 号：TF821[冶金工程—有色金属冶金]