摘要
二次铝灰中含有大量Al、Al_(2)O_(3),以及一定量的MgAl_(2)O_(4)和AlN,直接堆存会造成环境污染及资源的浪费,而铝灰中Al、AlN及部分杂质在碱性浸出条件下可以溶出,剩余残渣成分与镁铝尖晶石材料(MA)成分较为接近。本研究以二次铝灰为主要原料,采用碱浸预处理联合火法烧结的方法,并以MgO为调配剂,制备MA材料,研究过程考察了碱浸工艺参数对Al及AlN浸出率的影响,分析了二次铝灰碱浸机理,并考察了烧结工艺参数对所制备镁铝尖晶石材料性能的影响,得到以下主要结论。碱浸试验表明,增大NaOH浓度、提高浸出温度、增大液固比、加快搅拌速率均有利于提高Al及AlN浸出率;在温度80℃、NaOH浓度1.6 mol·L^(-1)、搅拌速率300 r·min^(-1)、液固比12∶1的优化碱浸条件下,Al浸出率达到80.35%,AlN浸出率达到53.21%;二次铝灰中Al及AlN浸出反应本质上是水解反应,碱性体系促进其水解反应进行;以碱浸残渣为原料,按照MA材料配比MgO,在烧结温度1300~1400℃、烧结时间3 h的条件下可制备晶型完整、结晶度高的尖晶石材料;1400℃条件下制备的MA材料显气孔率为31.56%,抗压强度为50.22 MPa,高于国家行业标准《镁砖和镁铝砖》(GB/T2275—2007)(40 MPa)。
Secondary aluminum ash contains a large amount of Al,Al_(2)O_(3),as well as a certain amount of MgAl_(2)O_(4)and AlN.Direct storage would cause environmental pollution and waste of resources.However,Al,AlN and some impurities in aluminum ash can be dissolved under alkaline leaching conditions,and the remaining residue composition is relatively close to that of magnesium-aluminum spinel material(MA).In this study,secondary aluminum ash was used as the main raw material,and the method of alkali leaching pretreatment combined with pyrometallurgical sintering was adopted.MgO was used as the modifier to prepare MA materials.The research process investigated the influence of alkali leaching process parameters on the leaching rates of Al and AlN,analyzed the alkali leaching mechanism of secondary aluminum ash,and investigated the effect of sintering process parameters on the properties of the prepared magnesium-aluminum spinel materials.The following main conclusions are obtained.The alkali leaching test shows that increasing the concentration of NaOH,raising the leaching temperature,increasing the liquid-solid ratio,and accelerating the stirring rate are all conducive to improving the leaching rates of Al and AlN.Under the optimized alkali leaching conditions of a temperature of 80℃,a NaOH concentration of 1.6 mol·L^(-1),a stirring rate of 300 r·min^(-1),and a liquid-solid ratio of 12∶1,the leaching rate of Al reached 80.35%and that of AlN reached 53.21%.The leaching reaction of Al and AlN in secondary aluminum dross is essentially a hydrolysis reaction,and the alkaline system promotes the progress of this hydrolysis reaction.Spinel materials with complete crystal form and high crystallinity can be prepared by using the alkali leaching residue as raw material and the MA material ratio of MgO under the sintering conditions of 1300-1400℃and sintering time of 3 hours.The apparent porosity of the MA material prepared at 1400℃is 31.56%,and its compressive strength is 50.22 MPa,which is higher than the national industry standard“Magnesia Bricks and Magnesia-alumina Bricks”(GB/T2275-2007)(40 MPa).
作者
王日昕
曾邦兴
曾思琪
邓雅坤
韦江
王国庆
张勇
WANG Rixin;ZENG Bangxing;ZENG Siqi;DENG Yakun;WEI Jiang;WANG Guoqing;ZHANG Yong(Institute of Applied Physics,Jiangxi Academy of Sciences,Nanchang 330006,China;Jiangxi Huagan Henghao Environmental Protection Technology Company,Fuzhou 331800,China)
出处
《中国有色冶金》
北大核心
2025年第4期108-116,共9页
China Nonferrous Metallurgy
基金
国家自然科学基金资助项目(52004113)
江西省科学院院长基金(2022YCXZD2001)
江西省科学院博士项目(2025YYB02)。
