Effects of Preexponential Factor

Low Reaction Rate Constant. Here we consider a lower reaction rate constant with 

Because the reaction rates are almost 60% smaller, under the conventional feed arrangement the vapor rate increases by a factor of 30% to meet product specifications compared to the nominal case (Table 18.2). Product D takes a shghtly lower value than the base case (Fig. 18.5fl), and more energy is required to separate the product from the reactants. 

Following the optimization procedure, the optimal feed locations are Np A = 9 and = 17. This results in only a 5.5% energy savings (Table 18.2). 

EFFECTS OF FEED TTiAY LOCATIONS ON DESIGN AND CONTROL OF REACTIVE DISTILLATION 

Heuristic H4 Place the feed trays away from each other when the rate constants become smaller (e.g.. Fig. IS.lOfc). Similarly, move the feed tray locations closer to each other when the rate constants become larger (e.g.. Fig. 18.111 ). 

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