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Effect of flow rate on the quality of the produced water: At different inlet flow rates, the conductivity of the water output by EDI ultra-pure water treatment equipment changes very little with the operating current. This is because, in the circuit, the solution phase and the resin phase in the dilute chamber are connected in parallel; since the electrical conductivity of the ion exchange resin used is much higher than that of the water produced by electrodialysis, the resistance of the resin phase becomes the determining factor for the resistance of the dilute chamber. Ion transport occurs primarily through the resin phase, and within a certain range of fresh water flow rates, the flow rate has little effect on the resistance of the resin phase; as a result, the total current through the membrane stack does not change significantly, nor does the conductivity of the produced water. Therefore, the influent flow rate has little impact on the degree of hydrolysis. Effect of operating voltage on water quality of the produced water The water quality of the output from EDI ultra-pure water systems is closely related to the operating voltage. If the operating voltage is too low, it is insufficient to remove ions from the dilute chamber before pure water is discharged; both the electrodialysis process and the resin electroregeneration process become weak, and ion exchange is the main process that takes place at this time. As the operating voltage increases, the degree of hydrolysis increases and the resin regeneration becomes more effective, resulting in a decrease in the conductivity of fresh water. When the operating voltage reaches a certain level, the ion exchange process and the resin regeneration process reach equilibrium, and the conductivity of the produced water further decreases and stabilizes. However, an excessively high operating voltage will cause excessive water electrolysis and ion back-diffusion, thereby reducing the quality of the produced water. Therefore, it is recommended that EDI operate at an appropriate voltage.