Low pressure acid gas removal using amine

[Jibran]

I have a situation where we are compressing low pressure associated/flashed/vent wet sour gas, extracting LPG, C4 & C5+ liquids and using the residue gas stream for the fuel use. The gas rich in heavy hyrocarbons need to be sweetened before NGL recovery. Amine type treatment seems suitable. Gas parameters are:

Inlet CO2: less than 1 mole%
H2S: below 500 ppmv
Pressure, psig: 90 - 100
Temperature oF: 100 - 110
Mol. Wt. above 40
Gas Flow, MMSCFD: 50

As such CO2 removal is not necessary. Recovered acid gas from the amine unit would be incinerated. I was wondering if some of you have a similar experience (low pressure, low H2S/CO2 ratio, NGL rich). Any operating problems? What generic amine type would be the most suitable? Client based on their past experience is not very much in liking of MEA. Any suggestions? Thanks a lot for your time!

 

[Canoman]

I suggest looking into software from BR&E titled TSweet. It will allow you to run multiple cases with different amines for comparison's sake. For the gas stream you've mentioned, there will probably be a number of amines that would work. I would check into DGA, DEA and MDEA. DGA, like MEA, requires a reclaimer. Typically, DEA and MDEA do not.

 

[Canoman]

Sorry, forgot a link.

http://www.bre.com

 

[Jibran]

Thanks Canoman (Chemical)
I agree with you TSweet is another way of looking and comparing alternatives. However, I was primarily interested in someones' real life experience with low pressure gas such as the one mentioned in my original request. I had raised this question in the Process Engineering Forum as well. There are quite a few useful suggestions in that forum. Please have a look at the following thread:

thread798-95532

Jibran