Design and Optimization of a Chemical Looping Hydrogen Production System Using Steam Reforming for Petrochemical Plants.

Industrial pollution is a significant environmental concern, and researchers are seeking solutions to minimize its impact. Chemical looping combustion is an efficient technique to decrease CO emissions. This study delves into its application within petrochemical plants for hydrogen production. In addition to its high efficiency in hydrogen production, this method yields pure CO and nitrogen. The design features four reactors utilizing iron and nickel metals as oxygen carriers. A model in Aspen Plus was developed to simulate this design and evaluate its performance. Aspen Plus uses RGIBBS submodel which works based on minimization of the Gibbs free energy. The research findings indicate that this design significantly boosted the hydrogen production rate from 3380 kmol/h in conventional steam reforming reactors and 4258 kmol/h in the three-reactor chemical looping combustion setup to 4408 kmol/h. Lowering the temperatures of the iron and nickel fuel reactors, as well as the iron steam reactor, reducing the airflow rate, and increasing the pressure of the iron steam reactor all led to increased hydrogen production. Conversely, changing the pressure of the nickel fuel reactor had minimal impact. The inlet steam flow rate exhibited a nonlinear effect, initially increasing and then decreasing the hydrogen production rate.