高炉煤气重力除尘器内部流场及除尘效率的数值模拟

Numerical Simulation of Internal Flow Field and Separation Efficiency of BF Gas Gravity Duster

为了提高高炉煤气重力除尘器的除尘效率,在高炉煤气重力除尘器内采用了安装漏斗型挡板和将进气管由中心管改为锥顶进气2项技术。采用FLUENT软件对除尘器内的气相流场和颗粒的运动轨迹进行数值模拟。模拟结果表明:改变进气方式以后,与旋风除尘器相似,在重力除尘器内部产生了旋流;加入挡板后,在挡板下部形成一个气流死区,避免了二次扬尘的出现,而含尘气体与挡板间的碰撞是颗粒被分离出来的主要原因。固体颗粒的运动轨迹较为复杂,且带有一定的随机性,计算得出的除尘效率和实际试验数据吻合较好。

Two technical measures were adopted to increase dust-catching rate of the blast furnace（BF） gas gravity duster,installing funnel-type baffle and changing intake manifold from central tube to cone collector with roof inlet in the BF gas gravity duster.The gas flow field and particle trajectory in gravity duster were numerically simulated in 3 dimension by software FLUENT.Similar to dust collector cyclone,simulation results show that it can also produce swirling in gravity duster after changing gas-injecting method;the forming of the gas flow dead-zone avoids emergence of second fugitive dust after setting the baffles;the collisions between dust containing gas and the baffle were the main factor to cause particle segregation.The solid particle trajectory is very complex and stochastic.The calculated separation efficiency was also well fitted the reported experimental data.