Numerical model of collision aggregation and remove of inclusions after aluminum deoxidization in RH reactor
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摘要: 在夹杂物碰撞经典聚合模型的基础上,使用了指数级增长的夹杂物分组方式,建立RH铝氧反应生成夹杂物、夹杂物碰撞聚合和夹杂物去除过程的数学模型,从而对RH冶炼过程夹杂物的质量分数及分布进行预测。得到结论如下:模拟结果与文献给出数据有很好的吻合度,模型真实可靠。夹杂物质量分数随着金属铝的加入而快速增加,循环300 s后,夹杂物的总质量分数从最开始的0升至0.065%左右,夹杂物质量分数达到最大值,继而在上浮、壁面吸附和顶渣吸附的作用下去除。经过900 s左右的钢液循环后,夹杂物的总质量分数降至0.01%左右,其整体去除率在84.6%左右,说明RH循环对夹杂物有很好的去除作用。加铝后900 s,2 μm和50.8 μm的夹杂物质量分数的最大值分别为0.00002%和0.0078%。Abstract: Based on the classical model of collision aggregation of inclusions, the growth mode of exponential increase of inclusions is used to establish the numerical model of reaction of aluminum and oxygen, collision and aggregation of inclusions, remove of inclusions, for the purpose of predicating the mass fraction and distribution of inclusions during the process of RH. The simulated results are found out good agreement previous findings from the developed model, the mass fraction of inclusions is sharply increasing with the plunge of aluminum. The mass fraction of inclusions increases from 0 to 0.0065% after 300 s circulation. Then the mass fraction reaches the maximum value. Afterwards the inclusions begin to remove because of the float and adsorption by the wall and the top slag of RH. The mass fraction of inclusions decreases to about 0.01% after 900 s circulation. The percentage of inclusions removal is 84.6%. The circulation has effectively removed the inclusions in RH. After 900 s circulation the maximum mass fractions of inclusions of diameter 2 μm and 50.8 μm are 0.000 02% and 0.0078% respectively.
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Key words:
- RH /
- reaction of aluminum and oxygen /
- inclusions /
- collision aggregation /
- numerical model
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表 1 模拟参数及其数值
Table 1. Parameters and values of simulation
提升气体流量/
(m3·h−1)钢液重量/
t循环时间/
s初始溶解氧浓度/
%加入金属铝质量/
kg96 210 900 0.0658 336 -
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