Heat exchanger network integration of a hydrogenation process of benzene to cyclohexene considering the reactor conversion

Abstract

In chemical industrial processes, reactor is the core of the whole system and influences other units and the utility consumption. To reduce the energy consumption, it is necessary to consider the reactor design and heat exchanger network (HEN) simultaneously, and optimize the reactor parameters based on the HEN integration. A graphical method is proposed to optimise a selective hydrogenation process of benzene to cyclohexene. Since the selectivity of benzene to cyclohexene is affected by the reaction rate of the main reaction and the side reaction in CSTR, the relationship among reaction temperature, the conversion and selectivity of benzene is deduced based on the kinetic equations. Based on this, the HEN's Composite Curve diagram is extended with the conversion-temperature-energy curve accommodated, and the relation between the reactor and the HEN is analysed. In the analysis process, the temperature variation of the source is accommodated by shifting the corresponding inflection point of the composite curve. By this method, optimal reaction temperature, conversion, and the minimum energy consumption of the process are identified simultaneously.