Does anyone know what does it mean, when a nitrogen buffer tank capacity is written as 6000nM3?

Trying to size the Nitrogen Buffer Tank, but i don't know what it means by that capacity.

Neelrahs2006,
In my opinion, "6000nM3" is referring to 6000 m3 of gas at NORMAL condition.

You may read this article for definition of STANDARD & NORMAL (Click HERE) *

As you can see, the definition of STANDARD & NORMAL is different from organisations, field, discipline, project, etc...You have to look for the definition in you case.

* http://en.wikipedia.org/wiki/Standard_cond...re_and_pressure

Joe is correct.

Thanks for the info.

HI, continue to above question. I just want to clarify that, if i want to design a gas buffer tank to supply 5500 Nm3/hr for 60 barg to 30 barg. Is that i find the normalize tank volume?

P1*V1/T1 = P2*V2/T2
1.0133*V1/273.15 = 61.0133*5500/303.15
V1 = 298296 m3

P1*V1/T1 = P2*V2/T2
1.0133*V1/273.15 = 31.0133*5500/303.15
V1 = 151676 m3

to determine the size of the tank,
298296 - 151676 = 146620 m3?

Will it be very large?

sabahboyz,

It would have been better if you had started a new thread.

Your calculations don't make sense. Did you do an analysis of the units on both sides of the = sign?

What is missing from your problem description is the required buffer time. Let's assume you need 6 minutes of buffer time.

Rule of thumb approach:
You have 30 bar to play with. Now this roughly means that every m3 of buffer vessel will provide you 30 Nm3 of buffer volume. You need 5500 Nm3/hr * 6 minutes / 60 minutes/hr = 550 Nm3. So you need 550 Nm3 / 30 Nm3/m3 vessel = 18.33 m3.

Now this is only a rough estimation but I am quite sure you will be fine with 19 m3 of vessel.

The detailed calculation procedure for air and nitrogen buffer vessels has been discussed before on this forum --> use the SEARCH button.