Numerical Simulation Of The Effect Of Hot Metal Flow And Shear Stress On Blast Furnace Hearth Erosion

Long-campaign technology of blast furnace is an important measure for the sustainable development of iron and steel industry. To prolong the service life of blast furnace have great significance. Blast furnace longevity can not only directly reduce the expensive cost of overhaul, but also avoid the huge economic losses caused by stopping production.The blast furnace hearth is considered to be the most critical area for the campaign life of the whole furnace. Hot Metal Flow is one of the important factors for the erosion of hearth. It is very meaningful to reseach the hot metal flow shear stress, because shear stress is a major cause of hearth wall erosion.Based on the commercial computational fluid dynamics software, build a three-dimensional hearth model and calculate wall shear of hearth for the flowing situations for different taphole lengths and the different of deadman state. The conclusions are as follows.(1) The shear stresses of the side wall and hearth bottom decrease with the increase of taphole depth. Increasing taphole depth is proper to reduce the flushing. So the operations of reasonable taphole maintenance is good for reducing the hearth erosion.(2) The shear stresses of the side wall and hearth bottom Change is very small with the increase of deadman floating height. When deadman is sitting, the shear stresses of hearth bottom decrease markedly.(3) The shear stresses of the side wall and hearth bottom increase with the increase of the voidage of deadman. The increase of the voidage of deadman can reduce the flushing. It is good for longevity of hearth that blast furnace use high strength coke after reaction.(4) When more taphole uniform distribution and only one taphole is working, the distribution of shear stresses of the side wall and hearth bottom is similar to the single taphole hearth. The other three tapholes have little effects on the wall stress distribution. The Serious erosion area is on both sides of each taphole which is combined action area. Compared hearth of single taphole, time cumulative effect of wall shear stress for hearth of four tapholes is smaller. So hearth of four tapholes can reduce erosion, and improve the life of hearth.(5) When more taphole non-uniform distribution, tapholes distribution and taphole number have certain effects on the distribution of wall shear stress. The time cumulative effect of wall shear stress is large between two tapholes which Angle is 70°. In this area, the erosion is more serious than other area. So reasonable angle of taphole is helpful to reduce the hearth erosion for hearth of more tapholes.