Life cycle assessment of coal direct chemical looping hydrogen generation with Fe2O3 oxygen carrier

Coal direct chemical looping hydrogen generation (CDCLHG) is a promising technology to convert coal into high purity hydrogen. Cradle-to-grave life cycle greenhouse gas (GHG) emissions and primary fossil energy consumption (PFEC) analysis are developed to study the CDCLHG process in this paper. The results show that the total GHG emissions and PFEC of the CDCLHG process are 9.54 kg eq. CO2/kg H-2 and 312.02 MJ/kg H-2, respectively. The CDCLHG stage is the largest GHG emissions stage and the largest PFEC stage. The total GHG emissions of the CDCLHG process is larger than the ash agglomerating fluidized bed (AFB) gasification process, whereas the total PFEC of the CDCLHG process is smaller than the AFB gasification process. In addition, the sensitivity analysis demonstrates that GHG emissions of the CDCLHG stage are sensitive to reducer temperature, reducer pressure and n(Fe2O3) to n(C). (C) 2019 Elsevier Ltd. All rights reserved.