9 replies to this topic

I know the gas density at 0 deg c and 1 atm pressure, would appreciate if anyone can let me know how to calculate the gas density at the supply pressure and temperature which is 675 psi and 46 deg C.

[ankur2061]

I know the gas density at 0 deg c and 1 atm pressure, would appreciate if anyone can let me know how to calculate the gas density at the supply pressure and temperature which is 675 psi and 46 deg C.

Avtar,

Use the spreadsheet I have posted on the following link:

http://www.cheresour...hl=spreadsheets

You will require your natural gas composition besides the operating pressure and temperature.

Also look at one of the previous posts on the forum:

http://www.cheresour...compressibility

As I have repeated time and again, use the search feature of the forum to look for answers to your prospective queries. Most of the times you will find your answers and will not require to post.

Regards,
Ankur.

[JoeWong]

Beside what Ankur has proposed, following may assist you :

• Two Useful Equations For Flow Conversion between Air - Vapor & Actual - Standard
• Avoid Confusion In "Standard" Flow Definition
• Relate NORMAL to STANDARD Volumetric Flow

Thanks Ankur,

The spreadsheets you posted were very helpful and I was able to work out the density of gas at higher pressure. Do we have any similar equations to calculate the specific heat at different gas supply pressures?

Would appreciate if you could post it at your earliest convenience.

Regards
Avtar

Thanks Joe,

The equations you posted were good to calculate the volume at different operating conditions but I was more interested to know the mass flow rate and therefore equation posted by Ankur was more applicable in my case.

Regards
Avtar

[ankur2061]

Avtar,

Make a separate post for specific heat and I will reply to you. Please don't mix topics.

Regard,
Ankur.

[kuldeepd]

hope this helps
http://www.processca...as_Density.aspx

[chemtan]

For density, just look back at chemical engineering basics:

D = (PM)/(RT)

D = Density
P = Pressure
M = Gas Mol.wt
R = Gas Constt
T = Temperature

[ankur2061]

For density, just look back at chemical engineering basics:

D = (PM)/(RT)

D = Density
P = Pressure
M = Gas Mol.wt
R = Gas Constt
T = Temperature

Chemtan,

You seem to forget the compressibility factor Z in the denominator of the equation, which is absolutely essential when dealing with gases at higher pressures.

Regards,
Ankur.

[chemtan]

Thanks Ankur... I got too deep in basics - into Higher Secondary level

So the correct formula:

D= (PM)/(ZRT)

Where,
Z = compressibility factor