Multiple Solutions, and Forced Unsteady-State Operation

Mixing, Multiple Solutions, and Forced Unsteady-State Operation 

Three important (complicating) possibilities were not considered in the treatment of reactors presented in earlier chapters (1) the residence time of the reactant molecules need not always be fully defined in terms of plug flow or fully mixed flow (2) the equations describing certain situations can have more than one solution, leading to multiple steady states and (3) there could be periods of unsteady-state operation with detrimental effects on performance, that is, transients could develop in a reactor. 

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