HYDROGEN AS A PILOT GAS TO IMPROVE POWER TURNDOWN IN SIMULATED ULTRA LOW NOx GAS TURBINE COMBUSTION

摘要

The use of a central pilot with a well mixed radial swirler combustor was investigated, at 600K and atmospheric pressure, to improve the power turn down of a low Nox combustor design. Hydrogen was compared with natural gas as the pilot fuel, using between 11 and 29% of the total energy input as hydrogen pilot fuel. With natural gas at low powers there was a hydrocarbon and CO emissions problem, but good flame stability was achieved and there was flame propagation from the pilot to the well mixed main combustion. The use of hydrogen as a pilot gas resulted in a 90% reduction in the HC and CO emissions at the simulated low power conditions. However, there was a significant increase in Nox emissions. The use of hydrogen as a pilot is a simple way to introduce hydrogen into existing industrial gas turbines so that the CO_2 reduction credits of 11-29% can be claimed, if the hydrogen comes from a renewable or carbon sequestrated source.