Solar Biomass Gasification Combined With Iron Oxide Reduction for Syngas Production and Green Iron Metallurgy

Abstract

The solar gasification of biomass with iron oxide for combined syngas and iron production was investigated. Both solar energy and biomass are promising renewable energies. The process of gasification converts solid carbonaceous feedstocks into either fuels or chemicals. However, conventional processes require partial combustion of the feedstock for energy supply and inherently suffer from high oxygen production costs and low syngas calorific value due to dilution with combustion products. Chemical looping gasification using solid oxides is an alternative option to tackle these issues. By supplying concentrated solar energy as the high-temperature heat source, it is possible to produce even more syngas from the process while enabling solar energy storage into dispatchable fuels. This work proposes to explore solar biomass gasification over iron oxide at high heating rates, representative of the conditions obtained in solar reactors. Thermodynamic equilibriums of gasification reactions between 100 and 1,500 • C were calculated and experimental results obtained at 1,100 • C with a specially designed induction furnace were reported for biomass gasification with iron oxide, water, or carbon dioxide as oxidizing agents. Solid products analysis showed that iron oxide can be reduced to metallic iron depending on the proportion of the oxygen carrier. These results indicate that iron oxide is an effective material for solar biomass gasification producing both syngas and iron via a novel green metallurgical process.

Carbon-neutral synfuel production via continuous solar H2O and CO2 gasification of oil palm empty fruit bunch

“…7, which is consistent with thermodynamic predictions (Fig. 5) and previous studies [36,42]. C2Hm yields between H2O and CO2 gasifying agents were found to be not significantly different.…”

Thermodynamic and Experimental Investigation of Solar-Driven Biomass Pyro-Gasification Using H2O, CO2, or ZnO Oxidants for Clean Syngas and Metallurgical Zn Production

“…The temperature for reaction completion was slightly higher than for H 2 O gasification (above 1000 • C (CO 2 ) vs. above 900 • C (H 2 O)). This is because of the Boudouard equilibrium (Equation ( 8)) that requires a higher temperature for reaction completion [23], which translates into much slower kinetics compared to carbon gasification with H 2 O (Equation ( 9)) [28]. Figure 5 shows thermodynamic equilibrium composition of biomass gasification with solid ZnO oxidant (Equation ( 4)) as a function of temperature at 1 bar.…”

“…Solar-driven gasification with gaseous or solid oxidants was previously investigated numerically [20], experimentally [21], and economically [22]. Concerning solid oxidants, Bellouard et al [23] employed iron oxide to gasify beech wood biomass and found that iron oxide was reduced to metallic iron, depending on the oxygen carrier proportion. They also concluded that iron oxide is an effective candidate for producing both syngas and iron via a novel green metallurgical process.…”

Experimental study of a two‐stage thermochemical cycle for hydrogen production

“…Bellouard et al, 44 evaluated the relevance of biomass gasification on iron oxide in an H 2 O or CO 2 atmosphere. The composition of the produced syngas was evaluated, showing greater production of H 2 after steam oxidization.…”