Preliminary Study of a Novel Gas Turbine Combustor Concept based on Hydrogen Synthesis from Kerosene Reformation

Addition of hydrogen as an additive in gas turbine combustor shows large benefit with respect to both performance and reduction in NOx levels. Due to complexity associated with dual fuel injection, it has not been implemented in gas turbines. In this study a novel combustor concept is proposed whereby a hydrogen rich mixture is synthesised within the combustor, thereby enhancing the combustion process. It is perceived that the novel combustor has two stages. Combustion of ~5% of the hydrocarbon fuel occurs in the first stage at a high equivalence ratio (above 1.5) in the presence of a catalyst, consequently producing hydrogen rich flue gases. In the subsequent stage hydrogen rich flue gases from first stage act as an additive to combustion of hydrocarbon fuel. Preliminary studies on the proposed combustor are presented in this paper. The preliminary studies demonstrate that the mixture of hydrocarbon fuel and air could be burned at equivalence ratios as low as 0.4– 0.5, giving better temperature profiles and larger stability limits than conventional kerosene fuelled combustors. Computational and equilibrium analysis demonstrate reductions in NOx, CO and CO2 with increased hydrogen synthesis levels. Lower casing temperature due to less emissivity of hydrogen flame and combustion at lower equivalence ratios leads to increase in life of combustor.