Characteristics of Coal Gasified Fuel Oxy-Combustion in H₂O/CO₂

(Combustion Test Results under Exhaust Gas Recirculation Condition)

Abstract

As a gas turbine for high-efficiency oxy-fuel IGCC system corresponds to a semi-closed type gas turbine, it is necessary to burn coal gasified fuel and oxygen near stoichiometric condition in CO₂-rich diluent following the recirculation of exhaust gas. Furthermore, there is concern that a very small amount of ingredient contained in fuel affects the purity of captured CO₂. In this study, to grasp the impurity concentration in exhaust gas of exhaust gas recirculation, the atmospheric pressure combustion tests recirculating exhaust gas with a small diffusion burner have been carried out and the impurity concentration and the behavior has been experimentally examined. As the results, CO and O₂ concentration was controllable by equivalent ratio, but NOx concentration from NH₃ in fuel was converged to a constant value, independent of equivalent ratio.