Selecting Amine for gas Sweetening Process 1

[Arthisiv]

I have a 3.9 mol% CO2 and 20 ppm H2S content in my natural gas feed with a feed rate of 160 tph with an inlet pressure of 4 MPa.

Pipeline specs are such that I need to reduce my acid gas content to 50 ppm CO2 and 3-4 ppm H2S.

For the gas sweetenign process, I am confused of which amine to use. Either DEA or mixed Amine (MDEA+MEA)? Does any one have any experience in choosing an amine for an acid gas removal process?

 

[dogtop]

Here is some info that could help in getting started.

http://www.qvf.com/en/ProcessSystems_3/Mineral Acids/AbsorptionofHydrogenChloride.shtml

HTH

 

[Zoobie]

dogtop:

What does HCl absorption have to do with amine selection for natural gas sweetening? Its like the original post asked "what is 2 plus 2?" and you responded "bananas".

Arthisiv:

When selecting amines I always consult with the vendor (i.e. Dow Chemical). Its pretty much necessary if you are going to be getting into any formulated MDEA blends. For some background here is an older paper by BRE.

http://www.bre.com/portals/0/technicalarticles/Selecting Amines for Sweetening Units.pdf

 

[nevine]

MEA (Monoethanolamine)
Used in low pressure natural gas treatment applications requiring stringent outlet gas specifications
MDEA (Methyldiethanolamine)
Has a higher effect on H2S than CO2 which allows some CO2 "slip" while retaining H2S removal capabilities.
DEA (Diethanolamine)
Used in medium to high pressure treating
does not require reclaiming.

 

[dogtop]

Sorry, posted to the WRONG thread. It should have been:

HCl capture/reclaim thread.

Thanks for the remark!!

 

[dcasto]

I have plenty of experience, but I'm not cheap.

The choice of amine is dependant on a combination of the variables.

Pressure (as pointed out above), Gas temperature, othe componets in the gas (like ethane, propane, RSH and all S compounds, local climate, energy costs, volume (or rate), and a bit of intuition on things like operability.