摘要 |
An oxy-fuel burner generates a long, luminous, stable and adjustable flame temperature profile flame by incorporating separate, fuel and oxygen jets oriented in a unique geometry. In one preferred embodiment, the fuel is injected horizontally at medium injection velocity (50-200 m/s) while primary oxygen is injected underneath the fuel jet at supersonic velocity (300-500 m/s). The supersonic velocity oxygen jet (20 to 50% required for stoichiometric combustion) entrains fuel and furnaces gases in it's core for the primary flame development over the furnace load. The subsequent mixing of the fuel, primary oxygen and entrained furnace gases establish a low NOx, stable, long and luminous primary flame. The secondary oxidant, preferably air or low purity oxygen (50 to 80% of stoichiometric needs), is injected above the flame using one or more oxygen jets to create an oxy-fuel flame with adjustable flame characteristics. The secondary oxidant completes unfinished combustion of flame gases containing CO, H2, CH4, soot and HC. The horizontal injection angle for all jets allow delayed mixing and a much longer flame. Due to the massive furnace gas entrainment process, the resulting flame provides adjustability in flame temperature profile as well as lower NOx formation. By changing the fuel, primary oxygen, and secondary oxidant injection velocities, the relative proportion of primary and secondary oxidants, and the relative positions of injectors, a fully adjustable flame is developed.
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