How to simulate cryogenic air separation (n₂/o₂/ar)
The real Linde double-column split: air is compressed, cooled toward cryogenic temperatures, and fed to a high-pressure column; its N₂-rich overhead and O₂-enriched bottoms are each let down through a JT valve into a low-pressure column as two separate feeds (the HP overhead entering near the top stands in for reflux from the shared condenser-reboiler a real double column uses — this solver's column MESH doesn't expose an external reboil-duty seam, so the two columns close their own reflux independently rather than literally sharing one condenser/reboiler; everything else — two pressure-cascaded columns, real multi-feed MESH, an actual argon side column — is real). A liquid side draw near the LP column's argon pinch feeds a crude argon column that rejects oxygen (the side draw's whole point — 'crude' because a real plant needs a further deoxo + purification train for pipeline-grade argon, out of scope here).
Also known as: air separation unit, ASU, cryogenic ASU, nitrogen and oxygen plant.
- 1Open the ready-made model
Open the "Cryogenic air separation (N₂/O₂/Ar)" model in the MaximaLabs workspace — no install, no license. It loads live on the canvas, ready to edit and run.
- 2Confirm the thermodynamics
This process is modeled with the PENG-ROBINSON property package over n2, oxygen, argon — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains COMP, COOL, 2× Arcol, 2× JT2, Lpcol. Every block is a real, solvable unit op you can reconfigure on the canvas.
- 4Run the simulation
Click Run. The deterministic solver converges the material and energy balances (recycles included) and fills the live stream table — the AI never invents a number.
- 5Read the results and iterate
Inspect the converged streams, tweak a spec, and re-run — or ask the AI copilot to explain a result or diagnose a failed solve in plain English.
- Thermodynamics
- PENG-ROBINSON
- Components
- n2, oxygen, argon
- Unit operations
- COMPCOOL2× Arcol2× JT2Lpcol
Opens live on the canvas — free, no install.
Explore the model & flowsheetFrequently asked questions
- What does the Cryogenic air separation (N₂/O₂/Ar) model simulate?
- The real Linde double-column split: air is compressed, cooled toward cryogenic temperatures, and fed to a high-pressure column; its N₂-rich overhead and O₂-enriched bottoms are each let down through a JT valve into a low-pressure column as two separate feeds (the HP overhead entering near the top stands in for reflux from the shared condenser-reboiler a real double column uses — this solver's column MESH doesn't expose an external reboil-duty seam, so the two columns close their own reflux independently rather than literally sharing one condenser/reboiler; everything else — two pressure-cascaded columns, real multi-feed MESH, an actual argon side column — is real). A liquid side draw near the LP column's argon pinch feeds a crude argon column that rejects oxygen (the side draw's whole point — 'crude' because a real plant needs a further deoxo + purification train for pipeline-grade argon, out of scope here).
- Is "Cryogenic air separation (N₂/O₂/Ar)" the same as a air separation unit?
- Yes — this model covers what is also called air separation unit, ASU, cryogenic ASU, nitrogen and oxygen plant. It runs the real process on the rigorous solver, so you can size and study it directly.
- Which thermodynamic method does it use?
- The PENG-ROBINSON property package, over n2, oxygen, argon — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains COMP, COOL, 2× Arcol, 2× JT2, Lpcol. Every block is a real, solvable unit operation you can reconfigure, add to, or remove.
- Do I need to install software or buy a license?
- No. Cryogenic air separation (N₂/O₂/Ar) runs entirely in your browser on MaximaLabs — free, no install, no license. Open the model to load it live and run the deterministic solver.
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