Today we start the 2006 publication programme of Members’ Research Projects with a Study Report entitled:
Chemical Looping Combustion
For Fossil Fuel Utilisation with Carbon Sequestration
Raymond Tan and Stanley Santos.
Chemical-looping combustion (CLC) is a combustion technology with inherent separation of the greenhouse gas CO2. This combustion process involves the use of a metallic oxygen carrier to allow indirect burning of gaseous fuel to yield CO2-rich flue gas to facilitate carbon sequestration.
Two reactors in the form of interconnected fluidised beds are used in the process. The metallic oxygen carrier undergoes cyclic oxidation (in air) and reduction (with gaseous fuel) reactions so that combustion takes place without contact between the fuel and air. Combustion of the fuel takes place in the absence of nitrogen, yielding flue gas consisting mainly of CO2 and water vapour.
The net chemical reaction over the two reactors is the same as for normal combustion with the same amount of heat released, but with the important difference that carbon dioxide is inherently separated from nitrogen, and no extra energy is needed for this separation.
Although the technology is still in its infancy, CLC offers the same advantages as oxy-fuel combustion with the added advantage of potentially higher thermal efficiency. This IFRF report reviews the fundamental principles of CLC, key results of oxygen carrier characterization studies, some CLC system concepts with associated design issues and thermo-economic assessments. The potential for related applications such as hydrogen production are also discussed along with promising directions for future research. The report was prepared by Dr Raymond Tan, Visiting Investigator at the IFRF from the Chemical Engineering Department, De La Salle University, Manila, Philippines and former IFRF Research Manager, Stanley Santos, now with the IEA in Cheltenham, UK
IFRF Members may download the report free of charge as a PDF file from http://www.research.ifrf.net after agreeing to the usual IFRF disclaimer. This page also provides links to all the IFRF Research Reports published in 2005.