Assessment of gaseous fuel combustion in chemical looping combustor: an experimental approach

• Reactivity and durability of materials impact gaseous fuel CLC performance. • Reactor design and parameters like temp and pressure are key to optimization. • Natural gas suits CLC due to high reactivity and clean-burning properties. • CO and HC emissions rise at high flow rates, showing incomplete combustion. • CO 2 output peaks at 4 kg/hr, marking optimal condition for fuel oxidation. Chemical Looping Combustion (CLC) offers an efficient pathway for carbon capture by inherently concentrating CO 2 without energy-intensive separation steps. This study experimentally investigates the combustion of Liquefied Petroleum Gas (LPG) in a dual-reactor CLC system using a 50 g bed of iron-based oxygen carrier (150 µm). Tests were conducted at fuel flow rates of 2, 4, and 5 kg·h −1 under a constant air supply of 16.17 m 3 ·h −1 . The oxygen carrier substantially enhanced combustion, elevating the fuel reactor temperature from a baseline of 780 °C (air-only) to 905 °C, 918 °C, and 932 °C, respectively an average thermal enhancement of 18.6 %. CLC operation also increased the maximum CO 2 concentration to 72–74 vol% (dry basis) from 43–47 vol% in conventional mode, while CO emissions were reduced by 38–52 %. The system reached thermal stability 40 % faster (2.1 min) with the carrier, indicating accelerated kinetics via lattice oxygen transfer. These results confirm that LPG, despite its complex hydrocarbon nature, can achieve over 70 % CO 2 capture potential in CLC when paired with an iron-based oxygen carrier, demonstrating significant promise for retrofitting existing LPG infrastructure for low-carbon, high-efficiency combustion.