Hybrid solar-driven hydrogen generation by sorption enhanced–chemical looping and hydrocarbon reforming coupled with carbon capture and Rankine cycle

Hydrogen (H2) production from fossil fuels using Hydrocarbon Reforming Methods (HRM) accounts for nearly 95% of Global H2 production. Unlike hybrid CL-SR systems, the Integrated Solar-Driven Sorption Enhanced–Chemical Looping of Hydrocarbon Reforming (SE-CL-HR) utilises solar thermal energy from the CSP system to drive the endothermic decomposition of feedstocks. Furthermore, the simulated hybrid systems utilise recovered heat to generate electricity, reuse of by-product CO2 for more syngas production and CO2 capture by a reaction of CaO to form CaCO3. This work focused on modelling and simulating hybrid CSP systems and SE-CL-HR plants with HTF output temperatures between 750 - 1050°C. In this study, SAM and MATLAB are used to develop the CSP system. While the CSP result saved in the MATLAB workspace gets exported to Simulink to feed SE-CL-SMR, SE-CL-POX and SE-CL-ATR Aspen plus models. The integrated system is fed with CH4 as the working fluid of the solar furnace. Stoichiometric and Gibbs free-energy minimisation were employed to investigate the effect of operating parameters. The output of the integrated system shows ≥ 9.5% exergy efficiency in comparison to conventional HRM. In addition, CO2 capture by CaO and high-pH water (Ca, Mg, Na+, O2, OH- and Cl-) to produce CaCO3, MgCO3, and other valuable products were also investigated in a process simulation. The research results revealed that for 8.1 tons/hr of CH4 and 277.1 tons/hr of H2O (steam) flowrates, 62 tons/hr of H2 can be generated and 338.5 tons/hr of CO2 emission can be reused and captured by the adoption of these new innovative technologies.