Hello fellow engineers, I come bearing an interesting question. I'm currently in a trial period at a factory and I seem to have stumbled across an interesting situation.
Lets assume the following system
Well water - MMF(multimedia filter) - Chlorination - Chlorinated water tank - Water softening tanks (strong cationic resin) - 5um Filter - Dechlorination - NaOH addition - Reverse Osmosis Units - CEDI units (Continuous electrodeionization) - Ozonation Tanks -> Ultrapure water.
I had a massive drop in the amount of ozone in water (from 400ppb to 200ppb).
This isn't the case when the station is running on city water (the ozone generator starts every hour or so in order to keep the ozone levels at the necessary amount).
However when I'm switching to well water it is working full time and in this case not being able to keep the parameter high enough.
In my opinion, given the fact the ozone is a reactive species I'm guessing there is a water contaminant reacting with it leading to the low reading. Something is going through the system and reaches the final point. The water coming out from CEDI is ultrapure - having a conductivity of 1.8 S/m - which means there aren't enough ions in it to react with the ozone. I tested the CEDI outlet for Chlorine, Iron, Manganese, Total Carbon and they're all in the same parameters as before.
Does anyone have a clue what contaminant might be able to pass through the system and have an effect on the ozonation ? Is there something I'm missing here ? I've been thinking lately that it might be CO2, or maybe ammonia or chloramine, but those might be retained by the CEDI.