Conversion According to the Segregated-flow Model

To illustrate the use of Eq. (6-39) suppose we use the RTD for a stirred-tank reactor [Eq. (6-12)] but assume segregated flow. We wish to calculate the conversion for an irreversible first-order reaction. The function x(6) is, from the second entry of Table 2-5, 

In contrast, suppose complete micromixing is assumed. Then, for the same RTD, an ideal stirred-tank reactor results. The conversion for a first-order reaction in this case is given by Eq. (4-7), which is identical to the above expression for segregated flow. This verifies the conclusion of Eq. (6-36) that the extent of micromixing does not affect conversion for first-order kinetics (as long as the correct RTD is used). The same develop- 

CHAPTER 6 DEVIATIONS FROM IDEAL REACTOR PERFORMANCE 

Example 6-4 Consider the laminar-flow reactor described in Sec. 6-4 and calculate the conversion for a first-order reaction for which k- = 0.1. sec and 0 = 10 sec. 

Solution The RTD for this reactor is given by Eq. (6-20) or Eq. (6-22). The flow is segregated, so that Eq. (6-39) is valid for calculating the conversion. Since x d) for a first-order reaction is 

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SECTION 6-8 CONVERSION ACCORDING TO THE SEGREGATED-FLOW MODEL... 

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