Packed-bed reactors are tubular reactors filled with catalyst particles. In PBRs it is the weight of catalyst W that is important, rather than the reactor volume. The derivation of the differential and integral forms of the design equations for packed-bed reactors are analogous to those for a PFR [cf. Equations (2-15) and (2-16)]. That is, substituting Equation (2-12) for FA in Equation (1-15) gives
PBR design equation
The differential form of the design equation [i.e., Equation (2-17)] must be used when analyzing reactors that have a pressure drop along the length of the reactor. We discuss pressure drop ...