海绵钛副产品氯化镁高温气相氧化反应器内流场的模拟研究

Simulation study on flow field of sponge titanium byproduct magnesium chloride in high temperature gas phase oxidation reactor

摘要:

本文研究基于利用“原位热解—热法还原炼镁”海绵钛清洁生产新工艺,即还原蒸馏产生的气态氯化镁直接氧化热解制备高纯氧化镁及氯气,氧化镁经热法炼镁返回TiCl₄还原环节、氯气返回沸腾氯化环节作为原料,实现海绵钛生产中新的镁、氯循环。,并针对“海绵钛生产中新的镁、氯循环”中的关键步骤—气态氯化镁与氧气的均相热解反应的反应器进行研究。采用数值模拟和物理模拟方法研究了反应器模型内的浓度场和速度场,在氮气与二氧化碳流量比为6：1时,二氧化碳采用环向四口进气方式,气体混合不均匀度为0.02,气体混合程度最佳。

关键词:氯化镁;氧化热解;反应器;气体混合

Abstract:

_{: This study is based on a new cleaner production process of titanium sponge by in-situ pyrolysis-pyrolysis reduction magnesium smelting, in which high purity magnesium oxide and chlorine were prepared by direct oxidation pyrolysis of gaseous magnesium chloride produced by reduction distillation. Meanwhile, magnesium oxide is returned to TiCl4 reduction after thermal reduction and chlorine is returned to boiling chlorination to realize new cycle of magnesium and chlorine in sponge titanium production. This study is aimed at the reactor for homogeneous pyrolysis of gaseous magnesium chloride with oxygen, the committed step of the circulation of magnesium and chlorine generated in titanium sponge production. The concentration and velocity fields in the reactor model were studied by numerical simulation and physical simulation. When the flow ratio of nitrogen to carbon dioxide is 6:1, the circular four-port intake mode is adopted for carbon dioxide, the gas mixing heterogeneity is 0.02, reaching the gas mixing degree.}

Key words:magnesium chloride; oxidative pyrolysis; reactor; gas mixing