Yield reactor: modelling a reaction nobody has kinetics for — a PENG-ROBINSON process flowsheet
Pyrolysis, gasification and cracking share a problem: the feed is not a set of molecules with a stoichiometry, it is biomass or coal or a heavy residue, and there is no reaction network to write down. What you have instead is a measured product slate from a pilot run. The yield reactor (Aspen's RYield) is the unit op for exactly that case — you give it the slate, it gives you a stream. Here 100 mol/s of feed goes to 823 K and comes out as 112 mol/s of gas at a specified mass yield (31% CO₂, 28% water, 22% methane, 14% ethane, 5% hydrogen), for a 3.66 MW heating duty. The mole count rises and the mass does not: the yields are normalised so the product mass equals the feed mass exactly, which is the entire contract of a yield reactor and the one thing it will not let you get wrong. Be honest about what this is. It has no kinetics, no equilibrium, no residence time and no temperature dependence of the slate — change the outlet temperature and the products do not shift, only the duty does. It is a way to carry a measured yield through a heat and material balance so the rest of the flowsheet is right; it predicts nothing about the reaction itself. If you have a rate law, use kinetic_reactor; if the system reaches equilibrium, use gibbs_reactor. Reach for this one when you have neither, which for solid-feed conversion is most of the time.
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- Rigorous PENG-ROBINSON thermodynamics, solved by the same engine every simulation runs on.
- 1 unit operations modeled: PYRO.
- Focus areas: Reactor, Yield, RYield, Pyrolysis, Gasification, Biomass.
- Thermodynamics
- PENG-ROBINSON
- Components
- methane, co2, water, hydrogen, ethane
- Unit operations
- PYRO
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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("pyrolysis-yield-reactor")
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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