How to simulate flue-gas desulfurization: venturi wet scrubber
A coal/oil-fired power-plant stack gas (SO₂ in a hot N₂/CO₂/O₂/water flue) is cleaned in a high-energy venturi wet scrubber before the stack — the classic flue-gas-desulfurization (FGD) front end. The new `venturi_scrubber` unit op accelerates the gas through a throat where injected scrubbing water is atomized, and a stated fraction of the soluble SO₂ is absorbed into the drops and carried out as a slurry while the cleaned gas goes up the stack. Two cited pieces are computed: the momentum-exchange pressure drop `ΔP = ρ_L·(Q_L/Q_G)·v_gt²` (Calvert 1968; de Nevers — the L/G here is ~1.4 L/m³ and the throat runs 90 m/s, giving ~11 kPa, a real high-energy venturi), and the SO₂ removal (92% at this water rate) that drops the stack SO₂ to a fraction of the inlet.
- 1Open the ready-made model
Open the "Flue-gas desulfurization: venturi wet scrubber" 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 nitrogen, carbon_dioxide, oxygen, water, sulfur_dioxide — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains VS. 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
- nitrogen, carbon_dioxide, oxygen, water, sulfur_dioxide
- Unit operations
- VS
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.
- 1The gas absorption is a stated removal efficiency (a screening scrub — the rate-based reactive contactor with real liquid-phase alkali chemistry is the `absorber` / `rate_based_absorber`), the cut-diameter particulate physics is idle here (a gas-only feed), and ΔP assumes complete drop acceleration. A screening process-design starting point for scrubber sizing / pressure-drop budgeting, not a certified FGD performance deliverable.
Frequently asked questions
- What does the Flue-gas desulfurization: venturi wet scrubber model simulate?
- A coal/oil-fired power-plant stack gas (SO₂ in a hot N₂/CO₂/O₂/water flue) is cleaned in a high-energy venturi wet scrubber before the stack — the classic flue-gas-desulfurization (FGD) front end. The new `venturi_scrubber` unit op accelerates the gas through a throat where injected scrubbing water is atomized, and a stated fraction of the soluble SO₂ is absorbed into the drops and carried out as a slurry while the cleaned gas goes up the stack. Two cited pieces are computed: the momentum-exchange pressure drop `ΔP = ρ_L·(Q_L/Q_G)·v_gt²` (Calvert 1968; de Nevers — the L/G here is ~1.4 L/m³ and the throat runs 90 m/s, giving ~11 kPa, a real high-energy venturi), and the SO₂ removal (92% at this water rate) that drops the stack SO₂ to a fraction of the inlet.
- Which thermodynamic method does it use?
- The PENG-ROBINSON property package, over nitrogen, carbon_dioxide, oxygen, water, sulfur_dioxide — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains VS. 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. Flue-gas desulfurization: venturi wet scrubber 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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