狭缝型喷粉透气砖是铁水底喷粉脱硫预处理工艺重要功能性元件,对底喷粉脱硫工艺的顺利实施影响重大.结合实际应用情况,基于欧拉-欧拉双流体和颗粒动力学理论,对喷粉透气砖狭缝内气-固两相流进行了三维数值模拟,得到狭缝内的流场、压力场和颗粒相体积分数场分布.喷粉透气砖狭缝内颗粒相体积分数非均匀段长度一般为250 mm,加速段长度一般小于250 mm,在颗粒直径为20μm时单缝内的压降最大,为2350 Pa.工业试验结果表明,底喷粉工艺脱硫效率比同类型顶喷粉工艺提高15%以上.
The slot-type porous plug used for injecting pulverized coal into the ladle through a bottom position is an extremely important element for desulfurization during hot iron pretreatment, and it makes great effect on the trouble-free operation of this desulfurization technology. With the help of the Eulerian--Eulerian model and the particle dynamic theory, a three-dimensional model is constructed to evaluate the velocity, pressure and concentration fields of gas--solid two-phase flow in the slot of a porous plug. It is found that the concentration nonuniform length in the slot is about 250mm, the acceleration length is always less than 250mm, and the maximum difference in pressure is 2350 Pa on condition that the particle size is 20 μm. The result of industrial application shows that the desulfurization efficiency of coal injection through the bottom position is about 15% higher than that by the top lance.