实施强化预脱硅及间接加热脱硅新技术

IMPLEMENTATION OF THE NEW INTENSIFYING TECHNOLOGY OF SILICON PRE-REMOVAL AND SILICON REMOVAL THROUGH INDIRECTLY HEATING

脱硅是生产氧化铝的重要工序.通过对脱硅机理的分析和预脱硅条件的实验室研究,合适的预脱硅条件为温度95～100℃、晶种添加量50～80g/L、搅拌反应时间3～4h;工业应用后,提高了预脱硅效率,达到80%以上,减缓了套管加热器结疤生成速度,使间接加热脱硅机运行周期由原来的10天左右延长到3个月以上,提高了溶液浓度,使吨氧化铝蒸汽消耗降低了0.32t.

Silicon removal is very important in alumina production. In this paper the proper conditions for silicon pre-removal were determined through analyzing the mechanism of silicon removal and conducting laboratory scale tests.The conditions include the temperature, the seed addition quantity and the agitating and reacting time,which are 95℃ to 100℃, 50～80g/L and 3～4 hours respectively. The efficiency of silicon pre-removal was improved, reaching more than 80 %, when used in industry scale. The scarring speed of the silicon removal equipment was slowed down, the running period of silicon removal equipment through indirectly heating was extended, prolonged to 3 months, and furthermore, the solution concentration was increased, making the steam consumption per ton aluminum reduced by 0.32t.