(617bj) Performance Comparison of the 60wt% Fe2O3/Al2O3 Oxygen Carrier Under Various Reducing Atmosphere for Chemical Looping Combustion

Chemical-looping combustion (CLC) is a promising concept that can be used in power generation, which integrates power production and CO₂ capture. This technology features low energy penalty for CO₂ separation and thus low CO₂ capture costs. In the CLC process, a solid oxygen carrier (OC) that circulates between the fuel reactor and air reactor transports the necessary oxygen for the combustion.

The aim of this work is focused on the comparison of the chemical stability of the 60 wt% Fe₂O₃/Al₂O₃ oxygen carriers in a chemical-looping combustion with various gases, including the main gases from coal gasification (mixture of H₂ and CO), H₂ and CH₄. The TGA analysis results showed that the time of reduction reaction with H₂ is faster than the counterpart with the syngas or CH₄, while the oxygen transport capacities of the 60wt% Fe₂O₃/Al₂O₃ oxygen carrier were 14.8%, 14.3% and 15.4%, respectively. After the 20^th redox cycling tests, it is found that the stability was very good under syngas and hydrogen atmosphere. The oxygen transport capacity did not decay during redox cycle test. However, the stability of the 60wt% Fe₂O₃/Al₂O₃ oxygen carrier decreased with the number of cycles under methane atmosphere.