Key points are not available for this paper at this time.
The tremendous increase in energy demand due to increased population and rapid economics results in an increased level of atmospheric pollutants and global warming. The global shift to the use of renewable clean energies still has some restrictions in terms of the availability of the advanced reliable technologies and the cost of application compared to conventional fossil fuels. Until we can have this full conversion to renewables, the development of novel techniques for clean combustion of fossil fuels is appreciated. Forced by the simultaneous increased pressure of strict emissions regulations and the target of limiting the global warming to 2 °C, gas turbine manufacturers developed novel combustion techniques for clean power production in gas turbines as per the present review study. These novel techniques depend either on modification in the existing combustion system or developing novel burners for clean power production. In this review, different clean combustion techniques are presented including flame type variability, burner design, and fuel and oxidizer flexibility. The combustion and emission characteristics of different flame types including non-premixed/premixed, moderate or intense low-oxygen dilution (MILD) flameless combustion, colorless distributed combustion (CDC), and low-swirl injector (LSI) combustion flames are presented with their limitations for applications. Novel burner designs for clean burning in gas turbines are investigated in detail including swirl stabilized, dry low NOx (DLN), and dry low emission (DLE), catalytic combustion, perforated plate, environmental vortex (EV), sequential environmental vortex (SEV), advanced environmental vortex (AEV), and lean direct injection (LDI) micromixer burners. As an effective technique to control combustion instabilities within the gas turbine combustor, a fuel flexibility approach is studied, considering mainly hydrogen-enriched combustion and the associated concerns about the fuel variability technique. An oxidizer flexibility approach in gas turbines is also studied under a premixed combustion mode considering lean premixed (LPM) air combustion and oxy-fuel combustion, and both techniques are compared in terms of performance and emissions. Finally, the feasibility of the different clean combustion techniques is discussed along with the available market products utilizing such novel technologies.
Nemitallah et al. (Fri,) studied this question.