Feed/product heat exchange multiple steady states

Figure 8-19 Multiple steady states in system consisting of reactorplus feed/product heat exchange .

In this chapter, we have seen that multiple steady states can occur when an exotirermic reaction takes place in an ideal CSTR, and when a feed/product heat exchanger is used in conjunction with an adiabatic PFR. We might ask whether this multiplicity is coincidental, or whether there is a link between these two examples. 

CSTRs and combinations of an adiabatic reactor and a feed/ product heat exchanger can exhibit multiple steady states and associated phenomena, such as feed-temperature hysteresis and blowout ... 

Plug-flow membrane reactors arc not faced with potentially unstable states since no back mixing of mass or heat is involved. However, when the product is recycled, heat is exchanged between the product and the feed streams or dispersive backmixing exists, multiple steady slates can occur and membrane reactor stability needs to be considered. 

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