carbon capture amine system simulation in HYSYS

[gpss]

Hi all,

I am new to the forum and apologise if there is already a thread for this topic.

I am Meng university student currently simulating an amine system in HYSYS for carbon capture from a natural gas powerstation.

I aim to capture >90% CO2 using 30 wt % MEA, I have simulated the system at low pressure (the absorber must be operating at atmospheric), however I am currently only capturing around 25% CO2, the remaining 75% is lost via the absorber top. There is also a temperature cross over the absorber, some of the details are listed below:

Absorber
Feed: 35oC, 1.014 bara, flowrate 560 kg/s 4.7 mol % CO2
Lean amine recycle to abs: 40oC 1.014 bara,
lean amine loading 0.05
Rich amine loading 0.37
No of stages 25

I am simulating in HYSYS V8.8 using acid gas package.

I have also attached an excel file containing some stream data for reference.

If anyone could provide advise/ feedback as to why I may be losing so much CO2 it would be much appreciated.

Thanks in advance
G.S