阶段平衡降温法提取硅的研究

Study on Silicon Extraction with Balanced Cooling Method

研究阶段降温法提取硅的最佳工艺条件,考察合金在凝固过程中的保温温度、保温间隔时间、降温幅度及搅拌速度对初生硅生长及分布规律的影响,并比较不同终止温度和搅拌情况下的提取率。结果表明,当保温温度为900℃,降温幅度为10℃,保温间隔时间为20min时,硅的平均直径达到0.466mm,粒径大于3.35mm所占比例达到20.2%;当搅拌速度为50r/min,终止温度为640℃时,通过搅拌的方法提取的合金含硅量高达44.3%。

The optimum conditions for silicon extraction with balanced cooling method were studied. In solidification process, the effects of holding temperature, holding time interval, cooling range and stirring speed on the growth and distribution law of primary silicon were investigated. The extraction rates under different terminal temperature and in different stirring situations were compared. The results show that the average diameter of silicon particle is 0. 466 mm, the proportion of particle size 〉3.35 mm reaches 20. 2%under the conditions including holding temperature of 900 ℃, cooling range of 10 ℃ and holding time interval of 20 min. Meanwhile, the extraction rate of silicon is up to 44. 3% when stirring speed is 50 r/min and terminal temperature is 640℃.