Guys, I'm having huge trouble trying to solve a problem for a PCC-MEA unit simulated in HYSYS.
Context: I'm simulating a PCC-MEA unit to remove CO2 from a flue gas stream using MEA as solvent. I have a flue gas inlet with a certain %CO2 molar composition and a solvent inlet (MEA+H2O+CO2) also with a %CO2 (m/m) composition and about a 30%MEA (m/m) composition.
The problem is, it doesn't matter how much I try, the outlet flue gas stream has a bigger %CO2 than the inlet flue gas stream. I've tried many many alterations, such as tower pressure, adding pressure drops, changing the inlet MEA flow, inlet stream pressures, number of trays, mass transfer equations, but the only parameter that helped was lowering the solvent inlet temperature. The thing is, the top temperature of the absorption tower has to be around 40ÂșC, and lowering the solvent inlet temperature also lowers the absorber's top temperature.
I'm using the Acid Gas Package for this process and I've already tried using the "Adjust" tool to target the outlet CO2 composition changing the inlet MEA flow, but it didn't help.
Please, can you guys help me through this issue? It would be very appreciated, since I'm losing the little hair that remained after I had COVID-19.
Best regards,
Vitoria