Optimization Design of Pulverized Coal Discharged from an Aerated Hopper

The silo aeration technology,which has the advantage of low cost and low noise,has been widely used in discharging adhesive powder.The experiment of aerated discharging of pulverized coal was carried out in the self-built plexiglass hopper for determining the optimal aerated condition during the pulverized coal discharging.The result showed that aeration could promote the discharging remarkably,however,the influence of aerated height and velocity existed coupling effect.On the basis of the theory of bubble motion,the model of pulverized coal discharging was built considering the relative motion between bubbles and particles.The relationship between bubble size and aerated condition was associated based on the experiment.The calculated optimal height was H/D=12.25 and the optimal velocity was U_g=2.4U_mf.There was a good agreement between calculation and experiment.The deviation of calculated discharging rate was less than ±20% while 5.56 < H/D < 18,U_g > U_mf.