高投料量下炼铜闪速炉内熔炼过程的数值模拟

Numerical simulation of smelting process in copper flash smelters at high loading rate

以FLUENT 6.3为计算平台,建立了铜闪速炉熔炼过程数值模型,并针对高投料量下反应塔气粒两相变物理场信息分布变化特点展开仿真研究。结果表明:工艺风入炉后迅速膨胀,并在反应塔中心形成轮廓明显的主体气流柱;主体气流柱内外的温度和氧浓分布梯度变化较大;局部低温出现在精矿喷嘴下方,而高温反应核心区域则下移至反应塔中下部。综合多场耦合仿真结果可知:高投料量条件下精矿粒子与反应配风之间混合力度欠佳是造成高投料量反应塔内熔炼过程反应效率降低的主要原因。

A numerical model was developed and the simulation was carried out with FLUENT 6.3 to investigate the distributions of multi-fields in the reaction shaft of a flash furnace at high loading rate.The results show that the process air expands quickly after it is fed into the furnace and forms a large downward gas column in the centre of the reaction shaft.Great gradients are found in the gaseous temperature and concentration destinations across the main gas column.Moreover,a low temperature region is found under the concentrate burner while a steady high temperature region appears in the lower part of the reaction shaft.The computation also reveals that the poor mixing between the gas and the concentrate particles is the main reason accounting for the decreased reaction efficiency of the smelting process in the reaction shaft of high productivity.