What Impact Does the Inlet Water Flow Rate Have on an Ultrapure Water System?

The operation of an ultrapure water system is affected by many factors, one of which is the influent flow rate. The influent flow rate has a significant impact on the EDI system of the ultrapure water system, so it's crucial to ensure the influent flow rate is within the normal range when using it. Today, we'll discuss the impact of influent flow rate on ultrapure water systems.

The influent flow rate is related to the processing capacity of the EDI system, the quality of the influent water, and the influent pressure. Under the condition of a constant EDI system production capacity, the worse the influent water quality, the heavier the unit processing load of the module, and the lower the influent flow rate should be. During the module startup phase, care should be taken to avoid excessive instantaneous flow, which can cause membrane perforation.

Since the electron flow in the module is mainly transferred through the filling resin, the concentrate current, to a certain extent, becomes a key factor affecting electron migration within the module. Actual experiments have shown that reducing the concentrate flow rate can increase the system current and, to some extent, improve water quality. However, a lower concentrate flow rate is not always better. An excessively low concentrate flow rate can lead to a larger concentration difference across the membrane, resulting in concentration diffusion and affecting water quality. On the other hand, due to the very low solubility of weakly charged ions (Si) and their ionic compounds, they easily become saturated in low-flow-rate concentrate, thus affecting the removal of weakly charged ions. Based on field tests, the concentrate flow rate should generally be 5%–10% of the influent flow rate.

The main function of electrode water is to cool the electrodes and remove gases generated on the electrode surface. Generally, the electrode water flow rate is about 1% of the influent flow rate. If the electrode water flow rate is too low, it cannot remove the gases from the electrode surface in time, affecting the operation of the entire module.

This concludes the introduction to the impact of influent flow rate on ultrapure water systems. We hope this information is helpful. Ultrapure water systems have many instruments that display various data; during use, it is important to observe these data to ensure they are normal and to guarantee the normal operation of the ultrapure water system.