Analysis of Two‐Step Solar Thermochemical Looping Reforming of Fe₃O₄ Redox Cycles for Synthesis Gas Production

Abstract

A two‐step solar thermochemical looping reforming (STCLR) of CH4—Fe3O4 redox cycles via H2O and CO2 splitting is investigated for H2 and CO production. The P1 approximation is adopted for the radiation heat transfer and high‐temperature thermal characteristics of active materials in the reaction medium. A benchmark experimental setup for the conversion of solar energy to syngas based on the solar thermochemical technology is presented. The effects of operating conditions on the yield of H2 and CO as well as syngas production are investigated at both thermal reduction and oxidation steps. It is found that the key performance of two‐step CH4—Fe3O4 redox cycles for a higher H2 and CO production depends on the efficiency of methane and oxidizer (H2O and CO2) conversion. Furthermore, a substantial amount of H2 and CO production with carbon deposition is obtained when the thermal reduction is extended to the mixed oxide solid solution (FeO—Fe). Among the oxygen carriers, FeO exhibits a higher oxygen exchange for H2 production. However, the synergetic effect of FeO—Fe reactivity strongly contributes to syngas yield. The present solar reactor model can significantly contribute to the reduction of greenhouse gas emission by utilizing 40% of CO2 emissions into solar fuels such as H2 and syngas. The results indicate that highly selective syngas with an H2/CO ratio close to 2 can be obtained with a strong control of γ = H2O/CO2.

Thermocatalytic and solar thermochemical carbon dioxide utilization to solar fuels and chemicals: A review

“…At first step (endothermic process), solar thermal energy reduces MO x to M or MO x‐y while in second step (exothermic process) the reduced metal oxide reacts with CO 2 to yield CO. This strategy regenerates MO x to be reused during the first step 167 . The overall reaction express CO 2 splitting into CO and O 2 .…”

Thermochemical Energy Storage Performance Analysis of (Fe,Co,Mn)Ox Mixed Metal Oxides

“…Recently models have been developed to provide thermodynamic descriptions of (Fe,Co,Mn)Ox [42][43][44][45] systems. Guene Lougou et al [46][47][48][49][50] and Shuai [51,52] conducted studies on energy storage thermochemical reactor together with the synthesis of thermochemical energy storage material and Yabiabl et al [53,54] studied about the impacts of thermochemical reactor designs for thermal energy storage and conversion of thermal efficiency. The researchers were able to produce a material that could resist the high-temperature thermal reduction super magnetic nanoparticles coated with aluminum (NiFe2O4@Alumina), (NiFe2O4@ZrO2), as well as support transits into new active phases including hercynite class materials (FeNiAlO4 and FeAlO4), Fe-oxide phases (Fe2O3, Fe3O4, and FeO) and NiO, (Ni,Fe), and AlNi phases.…”

Comparative Performance Assessment of 300 MW Solar‐Coal Hybrid Power Generation System Under Different Integration Mechanisms

“…[ 7,8 ] Moreover, solar energy can be used for fuel production via steam reforming, dry reforming, photochemical, and thermochemical methods. [ 9–11 ] Even, solar energy can be integrated with a coal‐fired power plant for increasing the operation performance of the system while reducing pollutant emissions via the reduction of coal consumption. In this research, we considered the solar‐coal hybrid power generation (SCHPG) system, which is one of the low carbon power generation technologies.…”