关键词: 二次铝灰, 溶出过程, 氧化铝溶出率, 动力学, 超声协同

Abstract:

The dissolution process of sintered clinker by the secondary aluminum ash alkali method is an important step in the recovery of alumina oxide.Improper control of key parameters in the dissolution process can result in low alumina dissolution rate and high energy consumption.In order to improve the alumina dissolution rate，understand the dissolution mechanism of alumina oxide，and reduce the energy consumption in the dissolution process，the relationship between temperature，time，liquid-solid ratio，and alumina dissolution rate in the atmospheric dissolution process of sintered clinker by the secondary alumina alkali method was investigated，as well as the kinetics of NaAlO₂ dissolution process in the clinker.The effect of applying ultrasound on the alumina dissolution rate was also examined.The results showed that the optimal parameters for the dissolution process of the clinker were dissolution temperature of 80 ℃，dissolution time of 15 min，and liquid-solid ratio（mL/g） of 15，resulting in an alumina dissolution rate of 92.3%.The dissolution kinetics indicated that the NaAlO₂ dissolution process was controlled by internal diffusion，with an apparent activation energy of 13.45 kJ/mol.It was found that applying ultrasound could reduce the dissolution temperature to 70 ℃ and shorten the dissolution time to 9 min while maintaining the same alumina dissolution rate.These research results provided new theoretical references and basic data for reducing energy consumption and improving efficiency in the dissolution process of sintered clinker by the secondary alumina alkali method.

Key words: secondary aluminum ash, dissolution process, alumina dissolution rate, dynamics, ultrasound irritation