Simulation of Continuous Electrodialysis Metathesis Process for Conversion of Na ₂SO ₄ to K ₂SO ₄

Electrodialysis metathesis is an attractive technology for the production of potassium salt and the treatment of sulfate wastewater. It could realize the metathesis reaction and concentration in an electrodialysis process. A semi-empirical mathematical model based on Nernst–Planck equations was built to describe the continuous EDM process converting Na2SO4 to K2SO4. The parameters were determined by the experimental data. The simulated results were verified by the laboratory scale test and a pilot-scale experiment. The economy of an industrial scale process was evaluated. The current density had a significant effect on the capital cost of EDM, while the effect of feed concentration was small. The specific cost of EDM was lowest when the current density was 150 A/m2.