Simulation and Design of a Water-Gas Shift Catalytic Multitubular Reactor with Integrated Heat Exchange

A 2D steady-state phenomenological model used for sizing a multitubular catalytic reactor for water-gas shift reaction is presented. The model contemplates momentum, mass, and energy balances. In addition, the thermodynamic behavior is described by the Peng-Robinson-Stryjek-Vera equation of state. After the model validation, a set of equations was used in an optimization procedure to find the optimal reactor's dimensions and operational conditions, minimizing both capital and operating expenses. The results were compared with data from the literature, and the water-gas shift reaction has proven disadvantageous at a low temperature, with heat exchange, because this considerably increases the required catalyst amount. The multitubular reactor has shown to be appropriate in the studied temperature range (430-520 K) only for a more active catalyst or for a more exothermic reaction.