Development and testing of AZEP reactor components

The advanced zero emissions power plant (AZEP) project addresses the development of a novel “zero emissions,” gas turbine-based, power generation process to reduce local and global CO2 emissions in a cost-effective way.The key element in AZEP is an integrated MCM-reactor, in which (a) O2 is separated from air by means of a mixed-conducting membrane (MCM), (b) combustion of natural gas occurs in an N2-free environment and (c) the heat of combustion is transferred to air by heat exchange.This paper focuses on the development and testing of the ceramic components of the MCM-reactor (air separation membrane and heat exchangers). For compactness and manufacturability, a module design based on extruded square channel monoliths has been chosen. The manifold design enables gas distribution in a checkerboard pattern. Modules with contact area of >500 m2/m3 have been produced.Results from testing of the modules under close to realistic process conditions agree with model predictions. Extrapolation to AZEP process conditions gives an oxygen production rate of around 37 mol O2/(m3 s), or 15 MW/m3 power density (per net MCM volume). These values correspond to project targets and confirm the feasibility of the AZEP concept.