What is the amount of acid to add to the ion exchange membrane?
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May I ask, when adding 18% salt acid to an electrolyzer, what is the typical flow rate to use? Thank you!
The amount of acid added to the anode salt in the electrolyzer is not fixed; it changes gradually as the performance of the ion membrane deteriorates. The exact amount to add depends on the pH value or acidity level of the weak saltwater.
Less acid is added to the new membrane, while more acid is added to the old membrane
The amount of acid to be added depends on the requirements specified in the process parameters: the acidity level at the inlet should be less than 0.15N, while the acidity level at the outlet should be controlled between 0.001 and 0.005N. Compared to the old membrane, the new membrane has fewer and smaller pinholes, resulting in less leakage, as well as a lower requirement for acid addition.
We generally keep the pH at the anode outlet between 2.5 and 5; if it falls below 2.5, the acid addition control valve activates automatically. Usually, we maintain it around 3 to 3.5
For an outlet value of 2.5 to 5, it should be the pH value without acid added; when acid is added, it’s better to use acidity as a measure.
We analyze the acidity once a week, which is a comprehensive analysis of the electrolyzer; under normal circumstances, this is done through pH monitoring.