CO2 removal from syngas (Rectisol-style physical solvent) — a PENG-ROBINSON process flowsheet
A CO₂-laden syngas stream from gasification/reforming (H₂/CO with 25% CO₂, the actual Rectisol duty — scrubbing raw syngas ahead of methanol/ammonia synthesis, not treating pipeline natural gas) is sweetened by a cold-methanol physical-solvent absorber (chosen because chemical amine reactions aren't modeled here) down toward synthesis-loop spec, then the rich solvent is regenerated by a pressure letdown into a second flash that flashes the bulk of the absorbed CO₂ back off — the same letdown-valve-plus-flash regeneration pattern used for HDA's and methanol synthesis's own dissolved-gas trains. No solvent recycle loop (an honest simplification: the regenerated solvent is reported as a product stream rather than closed back onto the absorber feed). From the ChemSep casebook (CO₂ removal from natural gas), adapted to Rectisol's real syngas duty.
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- Rigorous PENG-ROBINSON thermodynamics, solved by the same engine every simulation runs on.
- 3 unit operations modeled: ABS, Letdown, Regen.
- Focus areas: Acid-gas removal, Physical solvent, Absorption, Syngas treating.
- Thermodynamics
- PENG-ROBINSON
- Components
- h2, carbon_monoxide, co2, methanol
- Unit operations
- ABSLetdownRegen
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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("co2-from-natural-gas")
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
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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).
aMDEA closed solvent loop (activated-MDEA acid-gas removal)
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