The University of Kentucky, Center for Applied Energy Research
is investigating oxygen carriers (OC) for chemical looping
combustion (CLC) with the goal of developing a pressurized
chemical looping combustion/gasification process for generating
electricity from coal. An important issue in the application of
CLC to a solid fuel is the effect of ash on the performance of
the OC. A previous study using a bituminous coal ash obtained
from an electric utility suggested that the ash was not
detrimental to the capacity and reactivity of two iron based OCs
and iron oxide already present in the ash may have contributed
additional OC activity. With the wide variety of coals used to
generate electricity world-wide, it is unlikely that all ashes
will have the same effect on OCs. This study was undertaken to
further investigate the impact on an iron based OC of four
different fly ashes representing bituminous, sub-bituminous, and
lignite coals. The ashes were collected from power plants in
Bulgaria (subbituminous), China