pH control issue in electrolytic dechlorination
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In my company, after dechlorinating the electrolyzed brine, alkali is added to adjust the pH value to 10–11, and then sodium sulfite is added. Now, due to other requirements, we are considering bringing this pH value down to around 7. I wonder what impact this will have on the removal of free chlorine, and what effects it will have on the manufacturing process Will the consumption of sodium sulfite increase significantly? Do any companies handle it this way? Please discuss this, thank you.
Generally, it is best to keep the pH between 10 and 11. A very small amount of sodium sulfite is required; if the pH is kept around 7, several times more sodium sulfite needs to be added, which leads to an increase in sulfate levels in the brine system.
The pH should preferably be no lower than 10; a value below 10 leads to high consumption of sodium hypochlorite. To save alkali? Excessly consumed sodium hydride is more valuable than the base
Is the poster trying to use neutral dechlorinated saline for direct denitration?
The amount of sodium sulfite used is about 4-6 times more, I guess
This post was last edited by aldd7611 on 2016-11-21 at 13:46. The pH was kept at 7; during the actual dechlorination process, in addition to an increased usage of sodium sulfite, it seems that free chlorine could not be completely removed. Excessive use of sodium sulfite would lead to an increase in the sulfate content in the recovered brine.
If the pH level is too low, the amount of sodium hypochlorite used must increase significantly. Have any manufacturers used hydrogen peroxide? I read an article stating that it works well and helps reduce energy consumption; manufacturers who have used it can share their experiences: lol
It was originally used barium chloride to remove sulfate ions; now that denitration has been introduced, a contradiction has been observed, which led to this idea.
We used barium chloride before, but now that denitration is in use, our consumption of sodium sulfite has increased by 8 times since the denitration system was put into operation. We’re thinking of controlling the pH value during chlorination to see if that can help reduce the use of sodium sulfite, as well as acid and alkali.
Since we started operating the denitration system, the consumption of sodium sulfite has increased by 8 times. Thinking of keeping it at 7, won’t the consumption of sodium sulfite decrease by a factor of 8?
Sodium sulfite is used to remove free chlorine from brackish water under alkaline conditions, and a pH range of 9–10 yields the best reaction results. The actual measured temperature has a significant impact on the final results of the detection electrode; here, we generally require that the temperature of the electrode not exceed 40 degrees.