Conversion and reactor sizing

Plug flow reactors mostly operate at essentially constant pressure but sometimes pressure drop due to friction is appreciable. Thus problems P4.05.30 and P4.05.29 reveal a significant effect of friction on conversion and reactor size. For flow in pipelines, the pressure drop is given by... 

Ultimately, the final choice of the temperature, pressure, reactant ratio and conversion at which the reactor will operate depends on an assessment of the overall economics of the process. This will take into account the cost of the reactants, the cost of separating the products and the costs associated with any recycle streams. It should include all the various operating costs and capital costs of reactor and plant. In the course of making this economic assessment, a whole series of calculations of operating conditions, final conversion and reactor size may be performed with the aid of a computer, provided that the data are available. Each of these sets of conditions may be technically feasible, but the one chosen will be that which gives the maximum profitability for the project as a whole. 

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