Corn wet milling: starch to high-fructose corn syrup — a SUGAR process flowsheet
The sweetener train of a corn wet mill, end to end on the new sugar thermo package. A 35 wt% starch slurry off the mill is saccharified to glucose (glucoamylase, Michaelis-Menten), part-isomerised to fructose, enriched by simulated moving-bed chromatography, and concentrated to syrup in a two-effect evaporator.
Three results are worth reading rather than assumed. The isomerase lands at 42% fructose — the real equilibrium of glucose isomerase, which is precisely why an SMB exists downstream: the reaction cannot reach HFCS-55 on its own. The SMB then splits on the cited Ca²⁺-resin affinities (fructose H=0.69 vs glucose H=0.26), sending fructose to the extract and recycling glucose in the raffinate. The evaporator finishes at 77 wt% solids, commercial HFCS syrup spec.
That last number is only reachable because of boiling-point elevation. Modelled as inert solids the sugars give no BPE feedback and the evaporator is bimodal — it either does not boil or boils to dry sugar, with nothing in between. The sugar package (Norrish) supplies the real elevation, and syrup concentration becomes a smooth, controllable function of steam (42 → 77 wt% over the sweep range). Starch itself is carried as an involatile pseudo-component: it has no boiling point to characterise, so none is invented.
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- Rigorous SUGAR thermodynamics, solved by the same engine every simulation runs on.
- 3 unit operations modeled: 2× ISOM, SMB, 2× Evap2.
- Focus areas: Corn wet milling, HFCS, SMB chromatography, Enzymatic, Evaporation.
- Thermodynamics
- SUGAR
- Components
- starch, glucose, fructose, water
- Unit operations
- 2× ISOMSMB2× Evap2
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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("corn-wet-milling-hfcs")
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
High-fructose corn syrup: SMB glucose/fructose separation
The single largest-volume industrial SMB in the world — separating fructose from glucose to make 55-HFCS. A glucose/fructose isomerate (dilute in water eluent) feeds the native SMB unit op; on a Ca²⁺-form ion-exchange resin fructose is the more-retained sugar, so it reports to the extract (the sweetener product) while glucose leaves in the raffinate (recycled to the isomerase reactor in a real plant). Solved as the steady-state True Moving Bed equivalent — a purely isotherm-driven liquid separation, so the sugars need no vapor-liquid-equilibrium data.
Chiral API purification: continuous SMB chromatography
A racemic active pharmaceutical ingredient (R/S enantiomers, dilute in ethanol eluent) is resolved continuously by simulated moving bed chromatography — the workhorse of chiral-drug manufacture that legacy steady-state flowsheet simulators have no native model for (engineers script it in MATLAB). This uses the native SMB unit op, which solves the standard steady-state True Moving Bed equivalent: a 4-zone counter-current equilibrium-stage cascade whose zone flow-rate ratios sit inside the triangle-theory separation region, so the more-retained enantiomer reports to the extract and the other to the raffinate — the separation is driven by the chiral adsorption selectivity (the two enantiomers are otherwise thermodynamically identical).
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