This dialog appears when you click on the reaction kinetics button 
from the reaction tab of the following operations:
● Kinetic Well-Mixed (WM) Aerobic Bio-Oxidation
● Kinetic Plug-Flow (PF) Aerobic Bio-Oxidation
The following table shows a brief description of the variables appearing in this dialog. The table also displays their default values and their generally acceptable range:
|
Variable |
Default Value |
Range |
|
|
||
|
○ Rate Reference Component |
(none) |
Compo-nent |
|
○ Initial Guess of Extent (%) |
100.0 |
0-100 |
|
S-Term parameters: |
|
|
|
○ Substrate |
(none) |
Compo-nent |
|
○ Substrate Expression |
Monod |
Monod/ Haldane/ |
|
○ Ks (mg/L) |
5.0 |
Positive |
|
○ Ki (mg/L) |
50.0 |
Non Zero |
|
O-Term parameters: |
|
|
|
○ Ko (mg/L) |
0.05 |
Zero / Positive |
|
○ Other Components |
(none) |
Compo-nent |
|
○ Other Components Expression |
(none) |
Monod / Inhibition / None |
|
B-Term: |
|
|
|
○ Biomass Component |
(none) |
Compo-nent |
|
○ Biomass Expression |
First Order |
First Order / None |
|
Rate constant (k) parameters: |
|
|
|
○ Options |
Calc |
Set / Calc |
|
◙ Rate constant (k) (1/h) |
0.0 |
Positive |
|
○ Rate constant (k) calculation options |
Biode-grada-tion |
Biodeg. / Other |
|
○ kmaxo (1/h) |
0.2 |
Positive |
|
○ To (oC) |
20.0 |
Positive |
|
○ θ |
1.04 |
Positive |
|
○ ko (1/h) |
0.0 |
Positive |
|
○ E (kcal/mol) |
0.0 |
Positive |
Symbol Key: ○ User-specified value (always input); ● Calculated value (always output); ◙ Sometimes input, sometimes output
The following describes the available specification choices in this dialog; for more details on how these are implemented, please view see Kinetic WM Aerobic Bio-Oxidation: Modeling Calculations, Kinetic PF Aerobic Bio-Oxidation: Modeling Calculations, Anaerobic Digestion: Modeling Calculations or Kinetic Anoxic Reaction: Modeling Calculations.
The Rate Reference Component is typically the substrate, the consumption of which is represented by this reaction.
Through this block of variables, the user selects the kinetic expression (e.g., Monod, Haldane, Grau, First Order, None) for the ‘Substrate’, which is also identified by the user.
This term can be used to represent the impact of a second substrate (e.g., Oxygen). It can act as a switch that turns on or off a reaction based on the concentration of the Other Component.
This is for identifying the Biomass component (if any) that affects the kinetics of this reaction. Please note that the ‘Biomass’ drop-down menu displays all components that have been identified by the user as biomass components. More specifically, ‘Is Biomass?’ is a component property specified on the IDs tab of the Pure Component Properties Dialog of a component (through Tasks \ Pure Components \ Register, Edit/View Properties). The availability of multiple Biomass components offers the user the flexibility to track different types of biomass (e.g., heterotrophic biomass, nitrifiers or autotrophic biomass) and use the appropriate type of biomass to catalyze each reaction.
If a first-order biomass term is selected, and the concentration of the selected biomass component in the feed stream is zero (i.e. the reaction is autocatalytic), then you must also specify an initial guess for the reaction extent % with respect to the selected rate reference component (unless for a Kinetic Plug-Flow (PF) Aerobic Bio-Oxidation operation).
The rate constant (k) is either specified by the user or calculated as a function of temperature using the Arrhenius equation or a modified Arrhenius equation developed to better fit experimental data of biodegradation reactions.