Experimental Demonstration of a Novel Gas Switching Combustion Reactor for Power Production with Integrated CO2 Capture

Abstract

This paper experimentally demonstrates the feasibility of a novel gas switching combustion (GSC) reactor as an alternative to the traditional chemical looping combustion (CLC) process for power production with integrated CO2 capture. Whereas the CLC process circulates an oxygen carrier material between two fluidized bed reactors, where it is exposed to separate fuel and air streams, the GSC concept employs a single dense fluidized bed reactor where the oxygen carrier is periodically exposed to fuel and air streams. A lab-scale GSC reactor was operated autothermally (without any external temperature supply) to continuously convert cold feed gases into hot product gases, which would be suitable for driving a downstream power cycle. A parametric study was carried out to further investigate the behavior of the GSC concept. The reactor achieved a high CO2 capture efficiency (97.2%) and purity (98.2%) even without the use of a purging stage between the oxidation and reduction stages. A small amount of carbon deposition (around 1%) had a slight negative effect on the CO2 capture efficiency. Finally, the operation of a cluster of GSC reactors capable of delivering two steady process streams to downstream process equipment is discussed.