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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.

Given the drawbacks of the traditional MDEA absorption process, we introduced a hydrate-based gas separation approach. Then, to study the effectiveness of this method, we performed some hydrating experiments demonstrating that energy consumption could be remarkably reduced. However, the acid components (H 2 S and CO 2 ) in the product gas failed to meet the specification requirements of the sales gas. Consequently, a new technique was developed that integrated hydrate-based gas separation and chemical absorption for the sweetening of natural gas with high H 2 S and CO 2 contents. To evaluate the performance of this new integrated method, technical comparisons based on simulation and experimental data were conducted. The results showed that the new integrated method could effectively remove sour components, which resulted in the product gas being able to meet the sales gas specifications. Additionally, the integrated technique consumed much less energy than the traditional MDEA absorption process and its amine regeneration duty was only 42% that of the MDEA method. What is more, upon an economical evaluation being performed, it was shown that the integrated technique tremendously reduced the investment and operating cost.

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