H2 Cylinder

[madhavank007]

Dear Friends
Wish u very happy new year
i got one ?

i am using H2 Cylinder 51 inch height 9 inch dia pressure 125 kg/cm2 g

i am using hydrogen for my process
at 50 kg/cm2 i stopped the hydrogen.
is it possible to calc the remaining hydrogen amount with this data.
i don't know the cylinder weight
i know only initial amount,pressure and final pressure
can u able to help me


K Madhavan

 

[25362]

From thermodynamic tables obtain the specific volume (m[sup]3[/sup]/kg) at the starting P, T conditions. From the original known mass M[sub]1[/sub], kg, of gas you estimate the volume, m[sup]3[/sup] of the cylinder. For example, at 25[sup]o[/sup]C and the indicated pressure the specific volume would be, if I'm not wrong, 0.10715 m[sup]3[/sup]/kg.

Then V, volume of the cylinder = M[sub]1[/sub] x 0.10715.

Thermodynamic tables would also tell you the specific volume of hydrogen at the final P, T conditions. At 25[sup]o[/sup]C and the indicated pressure, it would be 0.25364 m[sup]3[/sup]/kg.

Having estimated the volume V of the bottle before, you could now estimate the mass of hydrogen left in the bottle dividing the V by 0.25364.

If the assumed temperatures and the readings I took from the NIST tables are OK, the reduction in mass would be:

100*[1-(0.10715/0.25364)] = 57.755%​

A Happy New Year.

 

[Latexman]

About 0.5 pound

PV = nRT
n = PV/RT
P = 50 kg/cm2 g = 711 lb/in2 g = 726 psia
V = 3.1415 x (4.5/12)^2 x (51/12) = 1.88 ft3
T = ?, so assume 60 F = 520 R
n = 726 x 1.88 / (10.73 x 520) = 0.247 lb-mols
m = n x MW = 0.247 x 2.01594 = 0.49 lb



Good luck,
Latexman

 

[jsummerfield]

Find a lot of useful gas cylinder data at

http://www.airproducts.com.

John