How to simulate perfusion bioreactor: continuous mab culture with cell retention
A continuous mammalian culture run in perfusion — fresh medium is exchanged continuously while an ATF/TFF device retains the cells, and density is set by a deliberate bleed rather than by the medium-exchange rate. That decoupling is the whole point, and it is what an ordinary chemostat cannot represent: at steady state the cell balance pins mu - mu_d to the cell-specific removal rate D_eff = D[phi + (1-phi)(1-R)], not to the dilution rate, so this culture holds roughly ten times the cell density the same feed would support in a chemostat. Lactate accumulates and inhibits growth, cells die at a basal rate (so the reported viability is below 100%), and the secreted antibody follows Luedeking-Piret kinetics — leaving in the cell-free harvest while the bleed carries the cells away. Set retention to 0.0 and this collapses exactly to the plain chemostat the 'bioreactor' example shows.
- 1Open the ready-made model
Open the "Perfusion bioreactor: continuous mAb culture with cell retention" 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 NRTL property package over ethanol, water — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains PERF. 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
- NRTL
- Components
- ethanol, water
- Unit operations
- PERF
Opens live on the canvas — free, no install.
Explore the model & flowsheetModeling assumptions & limitations
What this model captures, and what it deliberately does not — from the engineers who built it.
- 1Screening fidelity — the kinetic constants are illustrative rather than a regressed cell-line parameter set (no such databank ships with the kernel, deliberately); the model is isothermal, the retention device is a single efficiency number rather than a filter model (no fouling or sieving curve), and dissolved oxygen and pH are folded into mu_max rather than modelled.
Frequently asked questions
- What does the Perfusion bioreactor: continuous mAb culture with cell retention model simulate?
- A continuous mammalian culture run in perfusion — fresh medium is exchanged continuously while an ATF/TFF device retains the cells, and density is set by a deliberate bleed rather than by the medium-exchange rate. That decoupling is the whole point, and it is what an ordinary chemostat cannot represent: at steady state the cell balance pins mu - mu_d to the cell-specific removal rate D_eff = D[phi + (1-phi)(1-R)], not to the dilution rate, so this culture holds roughly ten times the cell density the same feed would support in a chemostat. Lactate accumulates and inhibits growth, cells die at a basal rate (so the reported viability is below 100%), and the secreted antibody follows Luedeking-Piret kinetics — leaving in the cell-free harvest while the bleed carries the cells away. Set retention to 0.0 and this collapses exactly to the plain chemostat the 'bioreactor' example shows.
- Which thermodynamic method does it use?
- The NRTL property package, over ethanol, water — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains PERF. 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. Perfusion bioreactor: continuous mAb culture with cell retention 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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Continuous mAb: perfusion bioreactor into TFF concentration
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