Do you have dew point and oxygen targets that you need to hit?
You should if you actually want to preserve it.
And it will take a lot more than 10% extra.
Usually people purge with warm dry air first to remove moisture.
Then you can nitrogen purge to get the oxygen down.
If you need to get under 4% oxygen you will need about 2.5x the static volume.
H,
To add to the discussion, I will use a calibrated sensor to monitor the residual O2 at the discharge. Don't rely only on calculation.
You will find some calculation in the document attached.
Pierre
Using nitrogen is expensive but my line will work after 3 years at least (phase 2 ) for that i cant leave it without nitrogen , i used dry air with acceptable dew point -14 . after i m gonna to preserve it with nitrogen.
i wonder how to calculate the volume of N2 in liter for 27 km of 12 inch ?
But do you have an O2 limit also?
I can't believe that you would just fill it and be at about 10% O2 and call that good.
This is just a dilution problem.