Rejected DI water 1

[mumjink]

Will rejected DI water have chemicals that would attack the adhesive on a stainless 316 SS body that has an attached volcanized viton seat to it? We are having separation problems in one of these systems and it has never been a problem before?

 

[micalbrch]

From what I know SS316 is absolutely suitable for deionized water. But I can't tell you how it perhaps affects the connection with the plastic seat.

 

[cheute79]

What do you mean by rejected DI water? Do you mean the "blowdown" or the stuff that hasn't been deionized? That is concentrated in whatever was in the incoming water, including, potentially, chlorides, nitrates, and others.

If you mean DI water, but somehow past its "expiration date" or somesuch, DI water is notoriously corrosive. Water is the universal solvent, and ultra-pure DI water wants to have something in it. If it isn't properly blanketed or inerted, it will absorb CO2, and acidify as carbonic acid. high quality DI water will slowly dissolve stainless steel, PVC, viton, or whatever. The piping material suggested for high quality DI was is non-pigmented polyethylene. That is why "old" DI water is rejected or sewered.