Low NOx premixed combustion of MBtu fuels in a research burner

The paper reports on the development and testing of a premix research burner for MBtu fuels. The burner has a quartz glass annular mixing section and a quartz glass flame tube to allow visualization of the flame. A central lance is used to mount modules for fuel injection, swirl generation, and flame stabilization. This allows a large number of variants with different swirl strength, mixing section length, fuel injection geometry, and flameholder size and shape to be easily tested. Experiments have been performed at atmospheric pressure and under high-pressure conditions (14 bar pressure, 400 degrees C air preheat temperature) for syngas with a H-2/CO ratio of up to 5. In a preliminary study, the mixing quality of the tested variants has been assessed with planar laser-induced fluorescence (LIF). High-pressure combustion tests show that low NOx (< 10 vppmd at 15 percent O-2) premix combustion of MBtu fuels under industrial GT conditions without dilution is feasible.