NGL fractionation: single-shell Petlyuk dividing-wall column — a PENG-ROBINSON process flowsheet
A natural-gas-liquids cut (ethane / propane / n-butane) split into three on-spec products by ONE thermally-coupled dividing-wall column instead of two columns in series. This uses the native Petlyuk unit op: a prefractionator whose reflux and boilup are supplied by the main column (the single condenser + single reboiler), solved by an outer Wegstein loop that converges the bidirectional vapor/liquid coupling to self-consistency — the coupling legacy sequential-modular solvers approximate with two connected columns whose recycle fails to converge.
Modeling assumptions & limitations
- 1The vapor-split and liquid-split ratios are specified inputs (not solved from tray hydraulics), and this is an outer-loop coupling of two rigorous MESH sub-solves, not a single monolithic Petlyuk MESH.
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- Rigorous PENG-ROBINSON thermodynamics, solved by the same engine every simulation runs on.
- 1 unit operations modeled: DWC.
- Focus areas: Dividing-wall column, Petlyuk, NGL fractionation, Thermal coupling.
- Thermodynamics
- PENG-ROBINSON
- Components
- ethane, propane, n_butane
- Unit operations
- DWC
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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("ngl-dividing-wall-fractionator")
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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A four-column NGL fractionation train — demethanizer, deethanizer, depropanizer, debutanizer — recovering pipeline-spec sales gas plus ethane, propane, and butane products from wellhead-pressure raw natural gas, after Luyben (Ind. Eng. Chem. Res. 2013, 52, 10741).
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