General Considerations and Material Balance

The process design of an LFR, like that of other types of reactors, may involve, for a specified throughput (q or FAo), calculation of the fractional conversion (/A) achieved at the outlet of a vessel of given size, or the size of vessel required for a specified /A. 

The material balance at steady-state is, on cancellation of 27rrdr, 

These equations are similar to the material-balance equations for a PFR, except that (for the LFR) they apply at a radial position r and not across the entire cross-section. The partial derivative is required because of this. 

Each of equations 16.2-1 and -2 may be interpreted to define ( — rA) at a point with respect to both radial and axial position. The average rate, (—rA), over the entire circular cross-section at a particular axial position is determined by integration as  

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