We have a 3.000 cm tank in which we keep a nitrogen pad. In order to maintain this pressure we use a blanketing valve, our desirable set point was 10 mbar because the pressure valve open at 30 mbar. One of our problems is that that when we are pumping product the flow meter of nitrogen reflex different ranges, for instance:
Product pumped (m3/h) Nitrogen flow (Nm3/h)
50 70
60 150
70 300
80 550
Until I know, the inflow of nitrogen is function of temperature, the pressure drop because of the evaporation/condensation phenomenon in the interface gas-liquid and directly proportional to the flow of pump. But what I see is that these relationship are different.
I would be pleased to received your advises.
Thanks, I have attached a brief file with a description.
Leticia
PD: Sorry for my English!