基于酸浸法去除水泥窑用后砖中氯化钾的研究

Research on Removal of Potassium Chloride from Brick Used in Cement Kilns by Acid Leaching

为有效去除水泥窑用后方镁石-铁铝尖晶石砖中存在的氯化钾,实现水泥窑用后耐材的工业应用,本工作主要利用硝酸、甲酸、草酸、柠檬酸等不同酸溶液浸泡水泥窑用后方镁石-铁铝尖晶石砖,探究不同酸溶液对水泥窑用后砖中氯化钾去除效果的影响。通过对处理后试样进行成分分析、物相组成及显微面扫分析发现,酸溶液有利于氯化钾扩散溶解,而有机羧酸由于可以与氯化钾发生络合反应,加速了氯化钾的水解电离,促进了氯化钾的去除。柠檬酸溶液去除氯化钾效果最佳,柠檬酸溶液处理后的物料符合轻集料国家标准中氯化物(以氯离子含量计)不大于0.02%的标准要求,处理后的物料可以再应用于工业生产中。

In order to efficiently remove potassium chloride present in the magnesia-iron-aluminum spinel bricks used in cement kilns,and realize the industrial applications of refractory materials used in cement kilns,this article mainly uses different acid solutions such as nitric acid,formic acid,oxalic acid,and citric acid to soak the bricks for cement kilns,and explores the effect of different acid solutions on the removal of potassium chloride in the bricks for cement kilns.Through the analysis of the sample composition,phase composition and microscopic surface scan analysis after treatment,it was found that the acid solution is beneficial to the diffusion and dissolution of potassium chloride,and the organic carboxylic acid can accelerate the potassium chloride’s hydrolytic ionization and promotes the removal of potassium chloride.The citric acid solution has the best effect of removing potassium chloride.The materials treated by the citric acid solution meet the standard requirement that the chloride(calculated as chloride ion content)in the national standard for light aggregates is not more than 0.02%,and the treated materials can be reused in industrial production.