Thermochemical storage analysis of the dry reforming of methane in foam solar reactor

The high-temperature heat transfer and thermochemical storage performances of dry reforming of methane in a foam reactor subjected to highly concentrated solar radiation is numerically investigated. Two new correlations for the volumetric heat transfer coefficient and the pressure-drop within foam structure are proposed through several experimental tests. Temperature and species distributions inside the reactor as well as the overall methane conversion and thermochemical energy storage efficiency under various operating conditions are predicted. The results indicate that the increase in inlet velocity and CH4/CO2 ratio produces a reduction in methane conversion, while increasing the solid-phase thermal conductivity promotes the conversion. The energy storage efficiency exhibits non-monotonous change with inlet velocity, feed ratio, and foam structural parameters. Compared to other foam structural parameter combinations, maximum conversion and efficiency are observed at porosity of 0.9 and pore diameter of 1.5 mm. Besides, the solid-phase thermal conductivity and foam structural parameters exert negligible effect on the H-2/CO ratio in the reforming process.