A Novel Circuit-Based Model of Electrodialysis Avoiding the Use of Empirical Parameters

• DOI: 10.1149/ma2023-02251374mtgabs
• Publication Date: 2024-02-08T19:42:40Z
• Authors: Jack Ledingham; Ngai Yin Yip; Kyra Sedransk Cam...; Alasdair Campbell

Electrodialysis (ED) is an emerging membrane-based electroseparation technology for desalination, water treatment, and ionic pollutant removal. Compared to conventional separation methods such as reverse osmosis, ED offers several advantages including lower energy consumption, higher selectivity, fouling propensity. Further, coupling with renewable electricity sources enables it be far more sustainable than competing technologies (reverse osmosis evaporation) across a wide range of scales. However, the design operation systems are still challenging due complex interactions between membrane, electrolytes, applied electric field. To address this issue, advanced process models required provide accurate predictions performance guide system optimisation. Existing tend highly dependent on empirical parameters thus only applicable narrow conditions require data sets validate. Therefore, in work we aimed develop glabal model without reliance experimental training data. Herein, present novel circuit-based ED. The considers membrane stack series resistors, where membranes electrolytes represented separate resistive elements. Crucially, resistance calculated directly from electrostatic interaction ions fixed charge groups, rather manufacturer or sub-model. This allows consideration ion identity electrolyte concentration when determining resistance. Ohm's law used relate voltage electrical current density, which then converted flux using Faraday's efficiency model. Historically, efficiencies transport numbers provided manufactures assumed constant. A has been developed by us function trans-membrane difference. space-wise material balance employed determine profile along stack, while time-wise tracks changes reservoir recirculating batch experiments. validate model, desalination experiments were conducted PC BED 1-4 compared demonstrated excellent matching variables conditions, efficiency, concentration. proposed various applications modelling, optimisation, economic analysis. It can evaluate impact different thickness, flow rate well optimise these. In summary, presented robust versatile tool simulation effective treatment. Two major advancements include have historically considered Figure 1