MEA post-combustion CO2 capture (electrolyte NRTL) — a ENRTL process flowsheet
The reference amine process on the reference amine: flue gas (12% CO₂ at 1.1 bar, 313 K) scrubbed with 30 wt% aqueous monoethanolamine at a lean loading of 0.20 mol CO₂ per mol MEA, the rich solvent pumped and heated to 388 K, steam-stripped at 1.9 bar, and the overhead condensed at 313 K into a CO₂ product and a reflux-water stream. It runs on the enrtl package — carbamate/bicarbonate/protonation speciation with Davies activity, the CO₂ partial pressure a function of loading and temperature — which is what sets the rich loading of 0.53 mol/mol the absorber reaches and drives the stripper the other way at 390 K. What it computes: 24 mol/s of CO₂ into 695 mol/s of rich solvent, a 39 mol/s CO₂ product at 94 mol% after the condenser knocks out 109 mol/s of water, 3.9 MW of rich-solvent heating for 650 mol/s of circulation (the sensible-heat penalty the sensitivity sweep traces against solvent rate) and 6.8 MW of overhead condensing.
Modeling assumptions & limitations
- 1The absorber and stripper are Kremser stage models with the K-value taken at the entering liquid, so the absorber sees the lean-end driving force everywhere and captures essentially all of the CO₂ — the 85-90% design figure of a real plant comes from the rich-end pinch and the packed height, which a stage-count shortcut does not resolve (the rate-based absorber was tried and its gas-film HTU of ~0.06 m at atmospheric pressure is not a number to show either) — and the stripper regenerates the solvent to zero loading where a real reboiled column leaves ~0.2. The loop is left open, the same simplification the mixed-amine showcase makes. Building this card also repaired the package: its (T,P) flash was a clamped split that turned a heated rich amine into pure CO₂ vapour at the full solvent rate; it is now a Rachford-Rice split that conserves composition through the heater.
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- Rigorous ENRTL thermodynamics, solved by the same engine every simulation runs on.
- 4 unit operations modeled: 2× Strip, RICH PUMP, 2× OVHD COND, Reflux DRUM.
- Focus areas: Carbon capture, MEA, Amine treating, Electrolyte, Post-combustion.
- Thermodynamics
- ENRTL
- Components
- n2, co2, o2, water, mea
- Unit operations
- 2× StripRICH PUMP2× OVHD CONDReflux DRUM
Opens in a new tab, loaded straight into the app — no setup.
Read the step-by-step guideReproduce this exact result from Python — the real client.get_example() → run_and_wait() path, not a mockup.
from flowsim.sdk import FlowSimClient
client = FlowSimClient()
example = client.get_example("mea-post-combustion-capture")
sim = client.create_simulation(example["title"], example["flowsheet"])
result = client.run_and_wait(sim["id"])
print(result["status"]) # "converged"
streams = client.streams(sim["id"])Related models
AMP post-combustion CO2 capture (hindered amine)
The MEA capture loop run on 2-amino-2-methyl-1-propanol: the same flue gas (12% CO₂ at 1.1 bar), 30 wt% AMP (8 mol%) at a lean loading of 0.10, steam stripping at 1.9 bar and an overhead condenser. AMP is sterically hindered — its carbamate is unstable, so CO₂ goes to bicarbonate and one mole of amine can carry one mole of CO₂ where MEA's carbamate stoichiometry stops at half — and the enrtl-amp package's speciation reproduces that: the rich loading comes out at 0.70 mol/mol against the MEA card's 0.53, so 500 mol/s of solvent does what 650 mol/s of MEA did, with 3.1 MW on the rich heater instead of 3.9. The CO₂ product is 27.7 mol/s at 93 mol%. Same.
DEA natural-gas sweetening at 50 bar
A high-pressure gas-treating unit on diethanolamine, the canonical secondary amine: 100 mol/s of 5% CO₂ natural gas at 50 bar and 313 K against 200 mol/s of 25 wt% DEA (5.4 mol%), the rich amine let down to 1.8 bar, heated to 388 K and steam stripped, the overhead condensed. The enrtl-dea package carries DEA's cited protonation anchor (pKa 8.9) with a screening-grade carbamate constant. What it computes: a treated gas that is pure methane, a rich loading of 0.52 mol/mol — right at the carbamate ceiling of a secondary amine — a 5.1 mol/s CO₂ product at 89 mol% (the rest methane co-absorbed at 50 bar and water), 1.2 MW on the rich heater. Same model bounds as the MEA card: Kremser stages with the K at the entering liquid, open loop, regeneration to zero loading.
Refinery acid-gas treating: MDEA/PZ absorber-stripper
Simultaneous CO₂ AND H₂S removal from a sour natural-gas / refinery off-gas stream by a piperazine-promoted MDEA solvent — the mixed-amine chemistry legacy tools reach for heavy rate-based/OLI add-ons to model. A high-pressure absorber contacts the sour gas with lean MDEA/PZ solvent (both acid gases absorb into the amine); the rich amine is heated and let down to a low-pressure steam stripper that drives the acid gases back off as a concentrated acid-gas stream and regenerates the lean solvent. Runs on the new 'enrtl-mdea-pz' electrolyte package: a generalized speciation (MDEA protonation + piperazine carbamate/dicarbamate + CO₂/HCO₃-/CO₃-- + H₂S/HS- + water) with Davies activity — it correctly reproduces piperazine's promotion (the blend holds more CO₂ at a given partial pressure than MDEA alone).
High-CO2 LNG with amine capture and CO2 reinjection
One 5.3 Mtpa LNG train on a reservoir whose gas is 14 mol% CO₂, where the CO₂ is not vented but compressed to dense phase and injected — 2.8 Mtpa of it, at 200 bar, which is the scale that makes this a storage project rather than a gesture. Two things make this different from every other LNG example here. First, the acid-gas removal is real chemistry, in the same flowsheet as the cryogenics: per-node thermo_overrides run the absorber, the rich/lean loop and the stripper on the 'enrtl-mdea-pz' electrolyte package (MDEA protonation + piperazine carbamate/dicarbamate speciation) while the gas train and the cold end run Peng-Robinson — the amine unit and the MCHE are not two models bolted together, they are one solve. Second, the CO₂ goes somewhere: the stripper overhead is knocked back, two-stage compressed with interstage cooling and drying, and pumped to 200 bar as a ~96 mol% dense-phase stream ready for a reinjection well, rather than leaving as a vent. The sweet gas is water-washed, dried and liquefied in the C3MR cold end to LNG at ~116 K.
Cement kiln calcination + CO2 liquefaction
Preheated limestone (CaCO₃) enters an indirectly-heated rotary kiln that calcines it toward CaO, releasing a CO₂-rich off-gas; the gas passes a knockout drum, then is compressed and cooled to liquefy the CO₂ for transport/storage.
Post-combustion CO₂ capture
A separator recovers 90% of the CO₂ from a flue-gas stream — the sustainability layer then tracks the captured tonnes.