Combustion of Methane and Biogas Fuels in Gas Turbine Can-type Combustor Model

The paper presents the numerical simulation on combustion of methane and biogas mixtures in the swirl burner can-Type of gas turbine combustion chamber. The study deals with the impact of mass fraction of carbon dioxide for biogas on emissions of noxious compounds during combustion. The investigations were done for four different fuels: pure methane (۱۰۰% CH۴), three biogases (۹۰%CH۴+۱۰%CO۲, ۷۵%CH۴+۲۵%CO۲ and ۷۰%CH۴+۳۰%CO۲), with the constant value of equivalence ratio ( = ۰.۹۵). The numerical results show that a low content of carbon dioxide in methane-air mixture leads to a better flame stability through an increase of the volume of the recirculation zone. The numerical analysis has shown that the biogas fuel allows a reduction of about ۳۳% on the NO emissions and about ۱۰% on the CO emissions and carbon dioxide contained in the fuel leads to the lowering of the flame temperature, whose effect reduces NO emissions. The results of the investigation clearly demonstrate that it is possible to use such fuels in combustion systems with swirl burners.

Keywords:

Biogas , Methane , Swirl combustor , NO