Thermodynamic Investigation of Process\nEnhancement in Chemical Looping Reforming of Methane through Modified\nCa–Fe Oxygen Carrier Utilization

Abstract

Production of various\nvalue-added chemicals\nthrough natural gas conversion with syngas as an intermediate is becoming\nincreasingly popular because of the abundance of natural gas and maturation\nof syngas-producing technologies. Chemical looping reforming is one\nsuch technology that is envisioned as a substitute to the existing\nsyngas production processes such as steam methane reforming, autothermal\nreforming, and partial oxidation of natural gas (POX) because of its\nsuperior thermodynamic capabilities and less parasitic energy requirements.\nThe proposed work makes use of CuO-modified Ca₂Fe₂O₅-based oxygen carriers for syngas production through\nchemical looping, where the system performance is subjected to thermodynamic\nscrutiny. The main objective of the proposed work is to assess the\nchange in syngas production capability and other process parameters\nbecause of reduced endothermicity of the process through CuO incorporation.\nThermodynamic simulations are carried out to assess the system performance\nat various operating temperatures, pressures, and lattice oxygen availability.\nParameters such as the effective thermal efficiency, cold gas efficiency,\nand exergy efficiency are calculated to evaluate the performance of\noxygen carriers with varying compositions of CuO. These parameters\nare measured for two process configurations: isothermal and thermoneutral.\nAn overall process simulation is further carried out to gain a deeper\nperspective of the changes occurring in the chemical-looping system\nbecause of CuO modification of the oxygen carrier.