A hierarchical model for novel schemes of electrodialysis desalination

Abstract

A new hierarchical model for the electrodialysis (ED) process is presented. The model has been implemented into gPROMs Modelbuilder (PSE), allowing the development of a distributedparameters simulation tool that combines the effectiveness of a semi-empirical modelling approach to the flexibility of a layered arrangement of modelling scales. Thanks to its structure, the tool makes possible the simulation of many different and complex layouts, requiring only membrane properties as input parameters (e.g. membrane resistance or salt and water permeability). The model has been validated against original experimental data obtained from a lab scale ED test rig. Simulation results concerning a 4-stage treatment of seawater and dynamic batch operations of brackish water desalination are presented, showing how the model can be effectively used for predictive purposes and for providing useful insights on design and optimisation. Self-Archived version: Campione A, Cipollina A, Bogle IDL, Gurreri L, Tamburini A, Tedesco M, et al. A hierarchical model for novel schemes of electrodialysis desalination. Desalination 2019;465:79-93.

Pressure-Induced Deformation of Pillar-Type Profiled Membranes and Its Effects on Flow and Mass Transfer

“…The channel thickness H ranges usually from ~0.1 to ~0.4 mm in RED applications [28], while a larger thickness is typically adopted in ED units, i.e., from ~0.3 to ~2 mm, especially in commercial stacks [1]. However, several recent researches on ED modelling and experiments have been focused on the use of thin spacers [29][30][31]. Therefore, the value of 200 μm adopted in the present study can be considered representative of both RED and ED applications.…”

Electrodialysis Applications in Wastewater Treatment for Environmental Protection and Resources Recovery: A Systematic Review on Progress and Perspectives

“…The performance of ED processes is governed by membrane selectivity and transport properties, non-Ohmic voltage drop given by the membrane potential ("back" electromotive force in most cases, electromotive force in RED), Ohmic voltage drop, and pumping power consumption. The voltage drop over the stack can be computed as [16,145,146]:…”

“…The performance of ED processes is governed by membrane selectivity and transport properties, non-Ohmic voltage drop given by the membrane potential (“back” electromotive force in most cases, electromotive force in RED), Ohmic voltage drop, and pumping power consumption. The voltage drop over the stack can be computed as [ 16 , 145 , 146 ]: where is the voltage drop over a single repeating unit (e.g., cell pair or triplet), N ru is the number of repeating units, I is the electric current, r el is the resistance of the electrode compartments (negligible in stacks with many repetitive units), and are the Ohmic resistance and non-Ohmic voltage drop in the repeating unit, respectively, the sign “+” applies for ED methods using an electric current provided by an external power supply, i.e., all ED methods except for RED, where the sign “−” applies. The Ohmic resistance encompasses the contributions from all compartments and IEMs (counting also spacer shadow effects [ 71 , 147 ]).…”

Water desalination by capacitive electrodialysis: Experiments and modelling

“…macroscopic membrane properties). This method has already been presented for both RED [64][65][66], and ED [49,[67][68][69][70].…”

“…In the CED model developed in this work, an existing semi-empirical hierarchical ED model [70] was properly modified and extended to account for the presence of capacitive electrodes which were modelled by means of a distributed RC circuit.…”