氧化铝高压溶出过程管道结疤的特性及清理方法优化  

Characteristics of Pipeline Scab and Optimization of Cleaning Method in Alumina High Pressure Dissolution Process

作　　者：杜英国 DU Yingguo

机构地区：[1]遵义铝业股份有限公司,贵州遵义563100

出　　处：《绿色矿冶》2023年第3期45-49,67,共6页Sustainable Mining and Metallurgy

摘　　要：氧化铝生产过程中,高压溶出管道结疤的产生不可避免。结疤会使传热效率降低,能耗增加,生产成本升高。本文在介绍结疤的成分和物相、结疤成因及危害的基础上,分析遵义铝业的高压溶出段结疤清除存在的问题,并对现有的高压水清除法进行优化改进。高压溶出管道结疤形成的机理及物相组成有很大差异,低温段结疤主要为钠硅渣,高温段结疤主要为钙钛矿、羟基钙钛矿。对于低温套管,可以通过提高清洗压力来实现结疤清除;对于高温段,可以使用熔盐加热干烧结合高压水清除的方法消除结疤。生产实践表明,在通盐干烧3~4 h、温度300~320℃、清理压力150 MPa的条件下,高温段套管结疤的清理效果明显改善,换热系数明显提高,均值达到900 W/m_(2)·℃。优化方法取得了较好的清理结疤效果。In the process of alumina production,the formation of pipeline scab in high pressure dissolution process is inevitable.Scab will reduce heat transfer efficiency,increase energy consumption and increase production costs.On the basis of introducing the composition and phase of scab,the cause and harm of scab,this paper analyzed the problems existing in the removal of scab in the high pressure dissolution process of Zunyi Aluminum Co.,Ltd.,and optimized and improved the existing high pressure water removal method.There are great differences in the mechanism and phase composition of the formation of high pressure dissolution pipeline scab.The low temperature section scab is mainly sodium silicon slag,and the high temperature section scab is mainly perovskite and hydroxyl perovskite.For low-temperature casing,scab removal can be achieved by increasing the cleaning pressure;for the high temperature section,the method of molten salt heating dry burning combined with high pressure water removal can be used to eliminate the scab.The production practice showed that under the conditions of salt dry burning for 3~4 h,temperature of 300~320℃and cleaning pressure of 150 MPa,the cleaning effect of casing scar in high temperature section is obviously improved,and the heat transfer coefficient is obviously improved,with an average value of 900 W/m^(2)·℃.The optimization method has achieved good cleaning effect.

关 键 词：氧化铝 高压溶出 结疤 高压水清理 

分 类 号：TF821[冶金工程—有色金属冶金]