Life cycle assessment of hydrogen production via iron-based chemical-looping process using non-aqueous phase bio-oil as fuel

This study is conducted to quantify the fossil energy input (FEI) and the global warming potential (GWP) of hydrogen production through iron-based chemical-looping process with CO2 capture using non-aqueous phase bio-oil (NAPB) from biomass fast pyrolysis as fuel. The eBalance software with Chinese Life Cycle Database is employed to implement this work based on the method of life cycle assessment (LCA). The LCA results indicate NAPB production consumes the largest fossil energy and contributes the largest GWP while chemical-looping hydrogen production (CLHP) plays a critical role in lessening greenhouse gas (GHG) emission. The net FEI and the net GWP of hydrogen production is, respectively, 0.597 MJ and -0.0767 kg CO2, eq. per MJ hydrogen gas via the proposed production pathway, far below those of the conventional hydrogen production via natural gas steam reforming and coal gasification. The sensitivity analysis shows the data uncertainty of the discussed parameters except the electricity consumption for NAPB production has no significant impact on the net GWP. The chemical-looping process with CO2 capture may be a more promising option to sustainably produce hydrogen gas especially using renewable biomass as fuel.