基于加压碱浸的电厂粉煤灰脱硅过程研究

Study on Desilication Process of Fly Ash in Power Plants Based on Pressurized Alkali Leaching

采用加压碱浸对电厂粉煤灰进行脱硅处理,可提取粉煤灰里的铝土物质。研究了碱浸温度、液固比(NaOH质量与SiO2质量比)、反应时间和碱质量浓度对二氧化硅浸出率的影响。研究结果显示,最佳反应条件为:碱质量浓度200 g/L,反应温度95℃,反应时间2 h,液固比2.5∶1,在此条件下的硅脱出率达24.23%。

In order to extract bauxite from fly ash,pressurized alkali leaching is used to desilicate fly ash in power plants.The effects of alkali leaching temperature,liquid-solid ratio(mass ratio of NaOH to SiO_(2)),reaction time and alkali mass concentration on silica leaching rate are researched.The results showed that optimum reaction conditions are as follows:alkali concentration being 200 g/L,reaction temperature being 95℃ reaction time being 2 h and liquid to solid ratio being 2.5:1.Under these conditions,the silicon removal rate can reach 24.23%.