This operation is used to represent material transformations that take place in a plug-flow reactor for which kinetic expressions are unknown or unimportant.
● Continuous Stoichiometric Reaction Procedure in a PFR
The user provides the mass stoichiometric coefficients (Ai) of the various components and the extent of reaction (x) based on the limiting component. Negative stoichiometric coefficients are used for reactants and positive for products.
The limiting component is identified based on the mass stoichiometry and the composition of the reacting mixture. For the limiting component (k) the following holds:
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where Fout,k is the mass flowrate of the component after the reaction, Fin,k is the mass flowrate of the component before the reaction, and x is the (possibly adjusted) reaction extent.
Now, the mass flowrate after the reaction (Fout,i) of any other component present (i) as a function of its mass flowrate (Fin,i) before the reaction, the extent of reaction (x), and the mass stoichiometric coefficients (Ai), is given by the following equation:
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where Ak is the coefficient of the limiting or extent-reference component.
To estimate the overall heating or cooling requirement, the model considers:
● the enthalpy of the reacting mixture
● the operating (exit) temperature
● the heat released or absorbed by the reaction as calculated based on the reaction extent and a user-defined enthalpy-reference component
See Vessel Sizing (Continuous Operations).
The interface of this operation has the following tabs:
● Oper. Cond’s, see Cont. Stoich. RXN in PFR: Oper. Conds Tab
● Volumes, see Continuous Vessel Operations (Design Mode): Volumes Tab and Continuous Vessel Operations (Rating Mode): Volumes Tab
● Reactions, see Stoichiometric Reaction/Fermentation Operation: Reactions Tab
● Labor, etc, see Operations Dialog: Labor etc. Tab
● Description, see Operations Dialog: Description Tab
● Batch Sheet, see Operations Dialog: Batch Sheet Tab
● Scheduling, see Operations Dialog: Scheduling Tab
