×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

scf/bbl to mol/mol
3

scf/bbl to mol/mol

scf/bbl to mol/mol

(OP)
Hello,

can someone help me convert scf/bbl to mol/mol ( its the loading of H2S in DEA)


Thank you

RE: scf/bbl to mol/mol

2
It is easiest if you split the problem into two halves - first work out how many mols of H2S you have, and then how many mols of DEA.

At standard temperature and pressure you can assume your gas is ideal and use the ideal gas law, i.e. PV=nRT. Taking standard conditions as 60F (519.67 Rankine) and 14.7 psia and R=10.7316 you will see that the volume of one lb mol of gas at STP is 379.4 ft3/lb mol.  So if you divide your scf of H2S by 379.4 you have the number of lb mols of H2S.

Now, looking at the DEA (assuming you mean diethanolomine) with a molecular weight of 105.14 and a density of 67.4 lb/ft3.  A barrel is 5.615 ft3. This makes 1 bbl of DEA
  1 x 5.615 x 67.4 /105.14 = 3.60 lb mol

From the first step you have the number of mols per bbl, so divide that answer by 3.6 and you have your answer in mol/mol.  Or you could combine the two factors and just divide the value in scf/bbl by 1366 (=379.4 x 3.60) to get the answer directly.

Katmar Software
Engineering & Risk Analysis Software
http://katmarsoftware.com

RE: scf/bbl to mol/mol

(OP)
you sure its not related to concentration the DEA

RE: scf/bbl to mol/mol

katmar:

I'm pretty sure that the original poster (intel2) is talking about scf of H2S per barrel of aqueous amine solution ... since most (if not all) amine gas treating units use a solution of amine in water.

So one must know the concentration of pure DEA in his specific aqueous solution before working out the conversion.

Milton Beychok
(Visit me at www.air-dispersion.com)
.

 

RE: scf/bbl to mol/mol

Yes, of course if the DEA is not pure then the concentration would have to be taken into account. Incomplete questions get incomplete answers.

Katmar Software
Engineering & Risk Analysis Software
http://katmarsoftware.com

RE: scf/bbl to mol/mol

The GPSA data book has a quick table that answers your question.  In FIG 21-3, DEA is listed as having a H2S pick up of 6.7 to 7.5 SCF/gal.  The foot note reminds us that the pick up is dependent on the partial pressure and concentrations of the DEA in water.

At low pressure and therfore low partial pressures, the loading is reduced, hence DEA should not be used with pressures under 200 psi unless there is no concern about top tray equilibriums that allow more than 10 ppm of H2S in the exit gas.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources