Hydrogen and Power Cogeneration Based on Chemical Looping Combustion: Is It Capable of Reducing Carbon Emissions and the Cost of Production?

摘要

This study presented a possible alternative to producing hydrogen and power on the basis of different chemical looping combustion technologies. To manifest the feasibility of such a design, the thermodynamics, environment, and economy were assessed in this study. Compared with traditional standalone systems (production of hydrogen and power, respectively), the designed systems were capable of saving beyond 16% of energy input, while reducing more than 98% CO2 emissions. As promoted by thermodynamic benefits, the chemical looping hydrogen generation (CLHG) system could achieve 3.04% efficiency gain as compared with the system that employs chemical looping combustion to generate heat for the steam methane reforming process (CLC-SMR). Moreover, the CO2 emissions per unit output energy of the presented method were reduced by 0.09 kg. It is noteworthy that the manufacture of oxygen carrier (OC) could not significantly impact life cycle carbon emissions or hydrogen production costs. To reveal the irreversible distributions, component irreversible analysis was conducted. To delve into the feasibility of the design, a sensitivity analysis was also conducted to explore the relationship between the OC performance and the global warming impact. Furthermore, financial assessment was also employed to analyze the systems' economic benefits.