This study elucidates the technologies employed in membranebased water purification processes. The theoretical underpinnings of semipermeable membrane functionalities are expounded upon through the lens of Onsager’s reciprocal relations in non-equilibrium thermodynamics, delineating the fluxes and the driving forces that instigate them. Utilising a simplified Onsager matrix tailored for the ion-exchange membrane electrodialysis process, computational fluid dynamics (CFD) simulations were conducted. The computations presented herein depict the intricacies of both dialysis and electrodialysis in saline water solutions.

A number of inorganic compounds, including anions such as nitrate(V), chlorate(VII), bromate (V),

arsenate(III) and (V), borate and fluoride as well as metals forming anions under certain conditions, have been

found in potentially harmful concentrations in numerous water sources. The maximum allowed levels of these

compounds in drinking water set by the WHO and a number of countries are very low (in the range of µg/l to a

few mg/l), thus the majority of them can be referred to as charged micropollutants. Several common treatment

technologies which are nowadays used for removal of inorganic contaminants from natural water supplies, represent serious exploitation problems. Membrane processes such as reverse osmosis (RO), nanofiltration (NF),

ultrafiltration (UF) and microfiltration (MF) in hybrid systems, Donnan dialysis (DD) and electrodialysis (ED)

as well as membrane bioreactors (MBR), if properly selected, offer the advantage of producing high quality

drinking water without inorganic anions.

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