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

(Effect of Exhaust Recirculation on Exhaust Gas Composition)

Abstract

As a gas turbine for high-efficiency oxy-fuel IGCC system corresponds to a semi-closed type gas turbine, there is concern that a very small amount of ingredient contained in fuel and oxygen affects the purity of captured CO₂. In this study, the atmospheric pressure combustion tests were performed by using fuel including NH₃ as minor components and by using diluent including NO as the exhaust circulation gas, and NOx emission characteristics were examined. As the results, most of NOx emission from NH₃ in fuel was NO, and when NH₃ is contained in fuel and NO is contained in diluent corresponding to the exhaust circulation gas, NOx emission corresponded to the sum of NOx emission formed by NH₃ in fuel and NOx emission formed by NO in diluent. And it was confirmed that NOx concentration in exhaust circulation gas changed by coal gasification fuel composition (e.g., CH₄ concentration).