Endothermic Reactions in a Cocurrent Cooling Fluid

TABLE 4-5 Reactor Design Strategies to Prevent the Phenomenon of Thermal Runaway in Plug-Flow Tabular Reactors 

This novel design shategy to simulate and control thermal runaway in a doublepipe reactor requires the simultaneous solution of four coupled first-order ODEs to describe conversion and temperature profiles within the inner pipe and in the annular region. Mass and thermal energy balances for exothermic reaction within the inner pipe are exactly the same as those discussed above (see equations 4-62 and 4-63). Hence, for one exothermic reaction (i.e., A products) in the inner pipe. 

Routside is adiabatic. For one endothermic reaction (i.e., B - products) for the cooling fluid in the annular region, equation (4-61) yields  

Step 1. Write the volumetric flow rate cooi as a product of the average velocity 

Step 4. Divide the entire thermal energy balance by the flow cross section in the annular region, - 

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