Simulation model

The two adsorption beds are identical. We model the adsorption beds according to the following specifications:

• We use three BedLayer submodels (NLayers = 3), one for each type of adsorbent that we use in the adsorption bed.

  

  Figure 2: Diagram of the bed layers

• We calculate the pressure drop according to Ergun3 (PressureDrop = Ergun).

• We create three copies of the RatesLDF submodel from the Adsorption library in the simulation-specific library, one copy for each adsorbent type that we use in the adsorption beds. Then, we update the rate expressions in each submodel to match the empirical data that we have for our alumina adsorbent (Alumina_LDF), UOP13X adsorbent (UOP13X_LDF), and VSA6 (VSA6_LDF) adsorbent.

  

  Figure 3: The adsorption rate submodels in the simulation-specific library

  These submodels calculate the adsorption rates of N2 and O2. These linear driving force (LDF) rate expressions are based on the paper by Farooq and Ruthven1. We use the Layer[].RateType parameters to specify the submodel for each layer.

  

  Figure 4: The adsorption rate submodel for each bed layer

• We create three copies of the RatesLDF submodel from the Adsorption library in the simulation-specific library, one copy for each adsorbent type that we use in the adsorption beds. Then, we update the rate expressions to match the empirical data that we have for our alumina adsorbent (Alumina_LDF), UOP13X adsorbent (UOP13X_LDF), and VSA6 (VSA6_LDF) adsorbent.

  

  Figure 5: The equilibrium loading submodels in the simulation-specific library

  These submodels calculate the saturation concentrations. They use the Extended Langmuir equation to calculate the equilibrium loading. We use the Layer[].IsoType parameters to specify the submodel for each layer.

  

  Figure 6: The equilibrium loading submodel for each layer