【摘要】 经过修正的Janssen公式能表达竖炉中炉料运动及气流阻力对料柱压力的影响,但不足说明悬料的原因。高炉悬料的力学机理是:在全炉平均气流速度和平均压差不很高的条件下,料柱中局部透气性恶化的料层的压差在气流速度高于临界流态化速度时,产生向上作用的局部超失重力;当此超失重力接近或大于上部料柱的压力时即产生悬料。这种悬料在均一散料柱中是不可能出现的。从这一机理出发,得出防止悬料和强化高炉冶炼所应采取的措施。更多还原

【Abstract】 The modified Janssen formula, relating the pressure of the burden column and thecountercurrent gas flow, has been verified experimentally. However this formula can notexplain the mechanism of hanging. The authors proposed the following mechanism: Ifthere exists a layer of poor gas-permeability in the burden column and if the gas velocityis increased to exceed some critical value, then the pressure drop of the gas through thatlayer would become greater than the layer weight. Therefore a force acting upward fromthat layer is induced. When this force becomes equal to or greater than the pressureof the overlaying burden, hanging will take place in the blast furnace. Such hanging,however, never occurs in the fluidized bed with granular particles of uniform size anddensity. The suggested mechanism has been proven in a 1/50 laboratory model of the1513 m~3 blast furnace and has been compared with the results of the actual industrialperformance of various blast furnaces. From this mechanism the authors arrived at the conclusions that the physical pro-perties of the raw materials, especially the screen analysis and the viscosity of the slagin the melting zone, are of vital importance when the driving rate of the blast furnaceis to be increased and hanging avoided.更多还原