An Exergetic Analysis of Membrane Unit Operations Integrated in the Ethylene Production Cycle

Membrane operations are an interesting answer to the necessity of a sustainable industrial growth. The possibility to rationalize an important petrochemical cycle by introducing membrane processes was investigated in the case of the ethylene production. The potentialities of catalytic membrane reactors (MRs) were analysed, coupling an exergetic analysis with the Process Intensification logic. Considering ethylene production by a catalytic process (ethane oxidative dehydrogenation), the introduction of a MR with a membrane (oxygen conducting membrane which selectively transports oxygen) for the oxygen separate feeding was considered. Moreover, the integration of a gas separation membrane system with the traditional reactor was proposed. The MR ethylene production process, compared to the TR one, achieves essential targets as the improved safety, the reduction of plant complexity, energy and exergy savings, increased flexibility as well as synergetic effects.