Effects of hydrogen addition on pollutant emissions in a gas turbine combustor

This paper presents an experimental work on the control of pollutants produced in a tubular hydrocarbon fueled combustor, by the injection of hydrogen in small quantities (less than 4 percent of total fuel). Hydrogen is introduced in the primary zone premixed with the air. Using this technique, with lean primary zone, it is possible to reduce the NO(x) emission level while maintaining CO and HC emission index at normal levels (CO and HC levels are greater without hydrogen injection). Injecting butane, instead of hydrogen, shows that there is no beneficial effect, so the influence of hydrogen in CO and HC reduction is due mainly to factors such as hydrocarbon substitution and chemical kinetics. An analysis to estimate the contribution of these factors is also included.