Ammonia cracking + H2 purification — a PENG-ROBINSON process flowsheet
Green ammonia is a widely proposed hydrogen carrier for shipping — easier to liquefy and transport than liquid H₂ itself, then cracked back to H₂ at the point of use. A fixed-conversion reactor dissociates NH₃ (2 NH₃ → N₂ + 3 H₂, endothermic, 99% conversion at a typical 600 C cracking-furnace outlet) and the cracked gas is polished by an adsorption stage to fuel-cell-grade H₂.
Modeling assumptions & limitations
- 1This models the adsorption stage as a single equilibrium Langmuir contact (competitive isotherm, H₂ weakly adsorbed vs. N₂/NH₃ strongly adsorbed) — a real PSA's cyclic pressure-swing/purge steps aren't modeled, only the equilibrium separation a cycle is built around. A true gas-phase membrane stage was left out for the same reason: the solver's `membrane` unit op is a liquid reverse-osmosis model (osmotic-pressure driven), not a gas-permeation membrane, so it doesn't apply here.
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- Rigorous PENG-ROBINSON thermodynamics, solved by the same engine every simulation runs on.
- 2 unit operations modeled: Cracker, PSA.
- Focus areas: Ammonia cracking, Hydrogen carrier, Adsorption, Green H2.
- Verified fast convergence — a real, measured solve time, not an estimate.
- Thermodynamics
- PENG-ROBINSON
- Components
- ammonia, n2, h2
- Unit operations
- CrackerPSA
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("ammonia-cracking-h2-purification")
sim = client.create_simulation(example["title"], example["flowsheet"])
result = client.run_and_wait(sim["id"])
print(result["status"]) # "converged"
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