Combustion Technology Available to Hydrogen Fuel

摘要

Hydrogen gas is generated from a petrochemical plant and oil refinery, or the like as a by-product gas. It has been desired to effectively utilize such gas as fuel for a gas turbine engine. Employing gas turbines with using such hydrogen gas can reduce the amount of natural gas usage as well as CO2 emissions. While NOx is generated during the gas turbine fuel combustion process, the amount produced largely depends on the combustion temperature. DLE combustors employ a premixed combustion method where fuel is premixed with air to minimize combustion temperature without the use of injected water or steam. Although this significantly reduces NOx emissions at low cost, fuel concentration needs to be controlled in order to maintain stable combustion. However, the difference in flame speed has made this a challenge, especially when burning hydrogen gas, which would often burn close to the burner and result in flashback. Kawasaki has developed and commercialized DLE combustors featuring a multistage burner process employing a pilot burner as well as main and supplemental burners. The new development builds on the proven technology of the DLE combustor and uses the pilot and main burners for natural gas, while enhancing the supplemental burners, which pose minimal risk of flashback, for burning hydrogen gas. This enhancement has enabled a mixed combustion of hydrogen gas amounting to almost 30% in quantity of heat. The low-NOx performance of the new technology has been verified by using the combustor test facilities which can be simulated engine actual condition. This paper is described in about such combustion technologies.