Optimal spatial temperature control of a steady-state exothermic plug flow reactor. Part I: Bang-bang control

This series of two papers deals with the spatial optimization of the heat exchanger temperature profile of an exothermic tubular reactor under the assumption of steady state and plug flow characteristics. The minimum principle of Pontryagin (optimal control theory) is applied in a straightforward, analytical sense. To enable a trade-off between process performance and heat loss a combined cost criterion is defined. In Part I of this series terminal costs-related to outlet reactant concentration and to outlet reactor temperature- are analyzed. It is generically proven that the optimal control input is of bang-bang type with no singular arc possible. This control keeps the heat exchanger temperature constant at its maximum or minimum value. In Part II of this series the terminal cost criterion is extended with an integral term that accounts for the global heat loss during the process.