Syngas combustion in a 500 Wth Chemical-Looping Combustion system using an impregnated Cu-based oxygen carrier

Chemical-Looping Combustion (CLC) is an emerging technology for CO₂ capture because separation of this gas from the other flue gas components is inherent to the process and thus no energy is expended for the separation. For its use with coal as fuel in power plants, a process integrated by coal gasification and CLC would have important advantages for CO₂ capture. This paper presents the combustion results obtained with a Cu-based oxygen carrier in a continuous operation CLC plant (500 Wth) using syngas as fuel. For comparison purposes pure H₂ and CO were also used. Tests were performed at two temperatures (1073 and 1153 K), different solid circulation rates and power inputs. Full syngas combustion was reached at 1073 K working at f higher than 1.5. The syngas composition had small effect on the combustion efficiency. This result seems to indicate that the water gas shift reaction acts as an intermediate step in the global combustion reaction of the syngas. The results obtained after 40 h of operation showed that the copper-based oxygen carrier prepared by impregnation could be used in a CLC plant for syngas combustion without operational problems such as carbon deposition, attrition, or agglomeration.