Review of Fuel/Oxidizer-Flexible Combustion in Gas Turbines

Abstract

Strict emission control regulations call for continuous advancement in existing combustion and carbon-capture technologies to mitigate the rise in pollutants and greenhouse gases from fossil fuel combustion. Concurrently, improvements in combustion systems would also yield lower fuel consumption and operational cost with greater efficiency. This review addresses these concerns and presents the overview of different combustion technologies and burner designs for cleaner power generation in gas turbines. Emission characteristics are discussed and compared for different combustion concepts, including lean premixed air combustion and oxy-combustion. Various gas turbine burner technologies, including dry low NO x , enhanced-vortex, perforated-plate, and micromixer burners, are discussed extensively, in terms of their operating principle, fuel flexibility, and potential for superior performance under oxy-combustion conditions. Enhanced-vortex and micromixer burners show remarkable flame stability and fuel flexibility and are thus recommended for implementation with hydrogen enrichment in future oxy-fuel gas turbines. The fuel-flexibility approaches for clean energy production, such as hydrogen combustion, hydrogen-enriched combustion, syngas combustion, ammonia combustion, and fuel blending, are explored as well. With the vast recent advances in the techniques of hydrogen production and storage, hydrogen-fueled gas turbines seem to be the perfect choice for clean energy production. The adiabatic flame temperature is identified as a key controlling parameter for the design of oxidizer-flexible combustors in clean gas turbines.

Numerical analysis supported with experimental measurements of premixed oxy‐propane flames in a fuel‐flex gas turbine combustor

“…In recent years, several review works [8][9][10][11] on gas-turbine combustion have emphasized on the usefulness of oxy-combustion owing to its inherent superiority in fuel/oxidizer-flexible combustion. This has also been reflected in the authors' recent review work, 12 where several dry low NOx (DLN) burner technologies in current air-fuel gas turbines have been pointed out for their suitability for switching to oxy-combustion, namely swirl-stabilized enhanced-vortex (EV), perforated-plate (PPB), and micromixer (MM) burners. Among these, swirl-stabilized burners have been investigated the most for oxycombustion application.…”

“…Propane, which is one of the primary constituents of commercial liquefied petroleum gas (LPG), is a fuel with higher carbon content and higher adiabatic flame temperature and Wobbe Index than methane. 12 Thus, propane has the potential to be used as an alternative fuel in existing methane-based premixed combustion systems. This makes comprehensive understanding of oxy-propane combustion imperative for real-life applications.…”

Analysis of methane, propane, and syngas oxy‐flames in a fuel‐flex gas turbine combustor for carbon capture

“…The determination of the deviator part using turbulent viscosity is carried out with Equation ( 14), where μ t represents the turbulent viscosity and S ij refers to the rate of strain tensor. In the model, the turbulent viscosity (μ t Þ is evaluated using the Smagorinsky-Lilly model, presented in Equation (15).…”

“…[11][12][13][14] The practicality of fuel-flexible approach has been highlighted in the authors' recent review article as well. 15 Even though, around 90% of the GTs worldwide operate on gaseous (natural gas) or liquid (liquefied natural gas-LNG) fuels, fuel flexibility can assert great advantage in areas with limited natural gas resources. Alternative fuels like propane, 16,17 syngas, [18][19][20] hydrogen, [21][22][23] and ammonia 24,25 are gaining much traction nowadays to overcome the dependence on natural gas for power generation.…”

“…Beside the inherent low‐emissions characteristics, oxy‐fuel combustion is also capable of fuel/oxidizer flexible operation, which is reflected on several recent reviews 11‐14 . The practicality of fuel‐flexible approach has been highlighted in the authors' recent review article as well 15 . Even though, around 90% of the GTs worldwide operate on gaseous (natural gas) or liquid (liquefied natural gas‐LNG) fuels, fuel flexibility can assert great advantage in areas with limited natural gas resources.…”