Experimental study of gas flow characteristics in vertical tank for sinter waste heat recovery

In the present study, the dimensionless method of Ergun's correlation is used to investigate the flow regimes and the pressure drop characteristics in the packed beds with non-spherical sinter particles. The sinter particles of average diameter d = 6, 14, 24 and 35 mm, with a range of sphericity, 0.63 <= Phi <= 0.89 are used in random packing with the range of bed layer voidage, 0.423 <= epsilon <= 0.53. The pressure drop of unit bed layer height in the packed bed is measured with particle Reynolds number (Re-p) ranging from 96 to 6888. The influences of gas superficial velocity and particle diameter on the pressure drop are analyzed in detail for the covered test cases. The critical Reynolds numbers marking transition among flow regimes and the revised Ergun's correlation are obtained according to the slope change of thef(p)-Re-p curve and the regression analysis of experimental data. The reliability of the revised Ergun's correlation is also verified. It is found that, the pressure drop of unit bed layer height gradually increases as a quadratic relationship with increasing gas superficial velocity for a given particle diameter. The pressure drop of unit bed layer height decreases as exponential relationship with the increase of particle diameter for a given gas superficial velocity. The air flow in vertical tank with sinter particles is under non-Darcy flow area for the actual condition and the critical Reynolds number marking transition from Forchheimer flow to turbulent flow in sinter bed layer increases as a third order relationship with increasing particle equivalent diameter. Compared with the previous Ergun's correlations, the revised Ergun's correlation is able to fit the whole experimental data best, and the mean deviation between the experimental data and the values calculated by the revised Ergun's correlation is 7.22%, showing good prediction. (C) 2015 Elsevier Ltd. All rights reserved.