Modelling of a Simulated Moving Bed in case of non-ideal hydrodynamics

Abstract

The one-dimensional hydrodynamic model proposed by Gomes et al. (2015) is coupled with adsorption and validated by comparing the concentration profiles of this one-dimensional model with those given by the CFD model of one adsorption column including obstacles as distribution network and beams. This one-dimensional model is capable of predicting the CFD results for different mass transfer rates, while the traditional dispersed plug flow (DPF) model is accurate for slow mass transfer rates only. The model proposed by Gomes et al. (2015) is capable of reproducing the adsorber Residence Time Distribution (RTD) while dissociating the selective zones from the non-selective ones. It is based on the CFD techniques developed by Liu and Tilton (2010) and Liu (2012) that transport the moments of the fluid age distribution and consequently calculate the degree of mixing (Danckwerts, 1958 and Zwietering, 1959). Then, this new model is integrated in a cyclic solver in order to perform Simulated Moving Bed (SMB) studies. The new model provides a detailed hydrodynamic description, which appears to be mandatory especially when mass transfer exchanges are fast, without undergoing the prohibitive simulation times of CFD models.

Residence time distribution (RTD) revisited

“…The concept of RTD is spread through many areas from solid processing (continuous blenders, extruders, rotary drums, fluidized beds) used in continuous manufacturing of chemicals, plastics, polymers, food, catalysts and pharmaceutical products ( Gao et al, 2012 ), to hydrodynamic modeling of real systems (liquid-liquid systems ( Nogueira et al, 2016 ), simulated moving bed ( Fangueiro Gomes et al, 2015 , Fangueiro Gomes et al, 2016 ), cascades of stirred tanks ( Toson et al, 2019 ), continuous flow polymerization ( Reis et al, 2019 ).…”

Simulations of unsteady flows with adsorption equilibrium in dynamic axial compression column

“…14 Moreover, CFD-based modeling and numerical simulation have been adopted to explore the transport phenomena in the preparative chromatography column. 13,15–17 In this study, CFD is proposed to explore the hydrodynamics of DAC columns based on up-to-date approaches of flow characterization and then to figure out numerical treatments that can be beneficial to simulations. In this research, CFD is used to access information on the inside of the DAC column, and the flow is considered to be laminar due to low flow speed with adsorption equilibrium in the micro-particle-packed column.…”

Desarrollo y producción recombinante de un péptido bloqueador de TNF para el tratamiento de trastornos autoinmunes inflamatorios.

“…En cromatografía, el valor de HETP es una medida que agrupa la contribución de las no idealidades de la dinámica del fluido al ensanchamiento de los picos. Se define como la relación de incremento de la gaussiana de un pico (𝜎) por unidad de longitud (z) de la columna [148,149,159,160].…”