Mathematical modeling and experimental study on dust removal efficiency of granular filtration bed

A cross-flow granular filtration fix-bed platform was set up to develop the high temperature pyro-gas and dust separation technology.Influence on the separation efficiency caused by key parameters including superficial gas velocity, dust concentration, filtration grain size and bed thickness was investigated.The results show that the separation efficiency first increases and then decreases when dust concentration rises within the range of 10.0-96.8 g/m³.Filtration bed packed with larger ceramic balls tends to have both lower efficiency and pressure drop.Separation efficiency and pressure drop increase with the thickening of the filtration bed.At initial operation state the filtration mechanism belongs to deep filtering.Along with the dust deposition into the bed, surface layer filtration enhances, which remove 45.0%-52.0% of the dust directly.An unsteady one-dimensional mathematical model is developed to describe the cross-flow filtration process, and to predict the net separation efficiency and dust deposition rate of platform under different operating conditions.The net efficiency of the filtration bed (0.6 m thickness, filled with 6 mm ceramic balls) in pyro-gas atmosphere declins to 82.94% by calculation.