2 replies to this topic

[Propacket]

Dear All,
I have performed a simulation of amine plant with 50% MDEA. Below is the brief summary of the plant:
Gas flow=8 MMSCFD
Inlet H2S=0.34 mole %
Inlet CO2=1.1 mole %
Outlet H2S=4 ppm
Inlet gas temperature=113F
Inlet gas pressure=260 psig
Lean MDEA flow=13 USGPM
Lean MDEA temperature= 129F
Lean MDEA pressure= 285 psig
Contactor overhead temperature=129F
Contactor bottom temperature=116F
The problem is that contactor overhead temperature is greater than the bottom temperature. Normally amine contactor bottom temperature is greater than the contactor overhead temperature. I think no issue with the overhead temperature because it will be close to the lean amine temperature. But I don’t why bottom temperature is so low. May be this is due to the low heat of reaction of H2S since it is a H2S removal plant and most of the CO2 slips with the treated gas. Can anyone comment how to resolve the issue? I am using hysys for simulation.

[Zauberberg]

Go through the first several chapters in "Gas Purification" by Kohl & Nielsen. You'll get an excellent information regarding Absorber temperature profiles.

[npp]

Sweet gas will be saturated with water. Check if the inlet gas is dry. Water vaporization requires heat, which can cool down the rich amine.