Hydrodynamic study of gas/solid moving beds by means of contact time distribution approach

In a gas/solid moving bed system, where the two phases flow co-currently, the contact time distribution (CTD) approach was used to characterise hydrodynamics and gas/solid contact interactions. The system considered consists of a moving solid phase with chromatographic properties used for the separation of a gas mixture of methane and pentane. Using a lumped parameter model, it was shown that residence time distribution (RTD) (methane) and CTD (pentane) curves enable the estimation of parameters involved in the model. More specifically, RTD curves provide hydrodynamic parameters and CTD curves characterise gas/solid contact interactions, i.e. equilibrium and mass transfer parameters. Moreover, the RTD moment of first order provides the void fraction of the system.