Chemical Looping Pilot Plant Results Using a Nickel-Based Oxygen Carrier

Abstract

A chemical looping pilot plant was designed, built and operated with a design fuel power of 120 kW (lower heating value, natural gas). The system consists of two Circulating Fluidized Bed (CFB) reactors. Operating results are presented and evaluated for a highly reactive nickel-based oxygen carrier, total system inventory 65 kg. The performance in fuel conversion achieved is in the range of 99.8% (CH 4 conversion) and 92% (CO 2 yield). In chemical looping reforming operation, it can be reported that thermodynamic equilibrium is reached in the fuel reactor and that all oxygen is absorbed in the air reactor as soon as the global stoichiometric air/fuel ratio is below 1 and the air reactor temperature is 900°C or more. Even though pure natural gas (98.6 vol.% CH 4 ) without steam addition w as fed to the fuel reactor, no carbon form action has been found as long as the global stoichiometric air/fuel ratio was larger than 0.4. Based on the experimental findings and on the general state of the art, it is concluded that niche applications such as industrial steam generation from natural gas or CO 2 -ready coupled production of H 2 and N 2 can be interesting pathways for immediate scale-up of the technology. © 2011, IFP Energies nouvelles.