铜底吹炉氧枪出口端蘑菇头生成过程水模实验研究

Hydraulic model test study on mushroom head at the end of oxygen lance of the bottom-blowing copper smelting furnace

氧气底吹熔池熔炼过程中,高温熔体会逐渐在氧枪出口周围形成蘑菇状的疏松多孔介质区,称为蘑菇头。大小合适的蘑菇头,既不妨碍送气量,又可保护氧枪。本文以铜底吹炉为原型,基于相似原理搭建水力模型试验平台,模拟得到蘑菇头的生成过程。蘑菇头的生成需要满足一定热力学条件,主要与低温气体温度和气体流量有关,稳定蘑菇头生成过程可以分为生成-破碎-生成反复阶段和稳定蘑菇头生成阶段,蘑菇头的尺寸、孔隙率以及生成稳定蘑菇头所需时间受气体流量的影响较大,而受氧枪倾角的影响较小。随着气体流量增加,稳定蘑菇头尺寸和孔隙率都会变大,生成稳定蘑菇头所用的时间则缩短。

During the oxygen bottom-blowing bath smelting process, high-temperature melt will gradually form a hemispherical porous zone with the mushroom shape around the outlet of the oxygen lance, known as the mushroom head. The mushroom head with an appropriate size can protect the oxygen lance and will not affect the gas injection. In this paper, bottom-blowing copper smelting furnace was taken as the prototype for the study, hydraulic model test platform is built by using similar theories, which simulates the formation process of mushroom head. The hydraulic model test results show that the formation of stable mushroom head requires certain thermodynamic conditions, which are mainly related with low-temperature gas temperature and gas flow. The formation process can be divided into generating-crushing-generating process and stable mushroom head generation process. The size, porosity and generation time of mushroom head will be mainly affected by gas flow and slightly affected by the angle of oxygen lance. With the increasing of gas flow, the size and porosity of stable mushroom head will become larger and it takes shorter time to generate the stable mushroom head.