Direct air capture Process Flowsheets & Simulations
Explore 2 validated, solved Direct air capture simulation flowsheets in MaximaLabs — real components: n2, oxygen, co2, water, calcium_carbonate, calcium_oxide. Open any one directly in your browser.
Solved via: COOLPROP.
Direct air capture with solid-sorbent calcination + CO2 liquefaction
A Carbon Engineering-style DAC train: a fan draws ambient air (400 ppm CO₂) through a liquid-KOH contactor (a fixed-recovery separator — the same simplification the existing carbon-capture example uses for chemical absorption, since no CO₂-KOH electrolyte package exists) capturing ~75% of the CO₂. The captured CO₂ is causticized and precipitated into CaCO₃ pellets by the real (unmodeled-in-detail) KOH/Ca(OH)2 loop — represented here as a matched pellet feed sized to the captured CO₂ rate, since the generic reactor unit op can't itself produce a solid product (only a rotary kiln's decomposition path can, which is exactly what's used next). Those pellets calcine at ~977 degC in an indirectly-heated rotary kiln (real Arrhenius decomposition kinetics, Sullivan-Maynard-Valentine residence time), releasing pure CO₂ that's compressed to ~20 atm and chilled to 250 K — above the real Span-Wagner CO₂ saturation pressure at that temperature, so the solved outlet stream is genuine subcooled LIQUID CO₂ (not just dense-phase pipeline gas) — while the CaO leaves for slaking and reuse (the lime side of the closed loop, out of scope for the same reason as the causticization step). Run the Carbon Footprint report on this example for the real Scope 1/2/3 CO2e + carbon-tax liability breakdown already built into MaximaLabs's report generator.
12 unit ops • COOLPROP
225 1
View & openSolid-sorbent fluidized-bed DAC with compression heat recovery
A second, lower-temperature DAC pathway alongside the liquid-KOH + rotary-kiln example: the captured CO₂ loads onto a solid sorbent, which regenerates in an indirectly-heated fluidized bed (real Wen-Yu minimum-fluidization sizing + Arrhenius desorption kinetics, the FluidizedBed) at 120 degC — the real low-temperature regime solid amine/physisorbent DAC sorbents actually use, versus the other example's ~977 degC calcination. The bed is fluidized by a recycled CO₂ sweep (self-sweep with product gas, a real design choice that sidesteps needing a steam-condensate knockout step). The desorbed CO₂ is compressed toward liquefaction pressure in one adiabatic stage — hot enough (~780 K discharge) that routing it through a heat exchanger against process utility water genuinely converts that water from subcooled liquid to a boiling mixed-phase stream before the CO₂ continues on to the same real liquefaction physics as the other DAC example.
14 unit ops • COOLPROP
222 0
View & open