Design equation ideal continuous plug flow

The various types of reactors employed in the processing of fluids in the chemical process industries (CPI) were reviewed in Chapter 4. Design equations were also derived (Chapters 5 and 6) for ideal reactors, namely the continuous flow stirred tank reactor (CFSTR), batch, and plug flow under isothermal and non-isothermal conditions, which established equilibrium conversions for reversible reactions and optimum temperature progressions of industrial reactions. 

For each of the ideal reactor types, viz. ideal batch reactor, plug-flow reactor (PFR), and continuous-flow stirred-tank reactor (CSTR), continuity equations or design equations can be derived using mass (or rather molar) balance equations for each species involved. 

Catal5dic gas-phase reactions are generally carried out in continuous fixed-bed reactors, which in the ideal case operate without backmixing. The model reactor is the ideal plug flow reactor, the design equation of which is derived from the mass-balance equation. As we have already learnt, in heterogeneous catalysis the effective reaction rate is usually expressed relative to the catalyst mass / cat, which gives Equation (14-1). The left side of this equation is known as the time factor the quotient is proportional to the residence time on the catalyst. 

The coimterpart of the ideal plug flow reactor is the ideal continuous stirred-tank reactor with complete backmixing of the rection mass. Because of the ideal mixing, the reaction rate is constant, and a simple design equation is obtained for the catalysis reactor (Eq. 14-3). 

The definitions of the three ideal reactors, and the fundamentals of ideal reactor sizing and analysis are covered in Chapters 3 and 4. Graphical interpretation of the design equations (the Levenspiel plot ) is used to compare the behavior of the two ideal continuous reactors, the plug flow and continuous stirred-tank reactors. This follows the pattern of earlier texts. However, in this book, graphical interpretation is also used extensively in the discussion of ideal reactors in series and parallel, and its use leads to new insights into the behavior of systems of reactors. 

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