铜PS转炉内的流域分布和混合时间研究

铜锍吹炼是铜精矿火法冶炼工艺的关键工序之一，目前全世界85%的冰铜均是采用PS转炉进行吹炼的。铜锍PS转炉吹炼是一个涉及化学反应、传热、传质的复杂的多相流体流动过程，吹炼过程中的流场分布特征、气锍渣分布规律以及物料混合特性对转炉生产率和铜回收率等指标起着重要影响。本文旨在通过可视化的冷态水模型试验模拟研究转炉吹炼高温冶炼过程流域分布和混合特性，进而对吹炼工艺进行优化。基于相似性原理建立了1:5等比例PS转炉冷态试验模型，采用高速摄像技术对吹炼过程的流场进行了动态记录，并基于图像处理技术对气液喷吹过程的流域进行了划分，包括喷吹区、喷溅区、强混合区、弱混合区、死区，并且对不同流域进行了定量化分析。此外，本文提出了一种新的判据，即“浓度稳定混合区波动极值”判据，用于判定不同示踪剂加入方式炉内的混合时间，进而确定了最佳的投料位置为喷吹波回落区，可明显提升转炉吹炼的混合效率。

Flow zone distribution and mixing time in a Peirce–Smith copper converter

Peirce–Smith copper converting involves complex multiphase flow and mixing. In this work, the flow zone distribution and mixing time in a Peirce–Smith copper converter were investigated in a 1:5 scaled cold model. Flow field distribution, including dead, splashing, and strong-loop zones, were measured, and a dimensionless equation was established to determine the correlation of the effects of stirring and mixing energy with an error of <5%. Four positions in the bath, namely, injection, splashing, strong-loop, and dead zones, were selected to add a hollow salt powder tracer and measure the mixing time. Injecting a quartz flux through tuyeres or into the backflow point of the splashing wave through a chute was recommended instead of adding it through a crane hopper from the top of the furnace to improve the slag-making reaction.