| 摘要 |
A combustor (10) is capable of reducing the noxious emissions such as fuel bound and thermal nitrogen oxide products during combustion of high nitrogen bearing and high aromatic content fuels. It includes a plurality of substantially concentric pipes (11 to 16) defining annular passages (12a to 16a) with annular venturi shaped divergent nozzles (20 to 24) to facilitate fast mixing of axially supplied air between adjacent annular passages. The longitudinal spacing between at least two adjacent nozzles defines first and second divergent cavities (30, 40). A fuel rich toroidal vortex (T) is formed in proximity to a central fuel jet in the first cavity (30) and advantageously converts fuel bound nitrogen to N2. A fuel lean toroidal vortex (T') formed in the second cavity (40) mixes hot combustion products with additional gaseous reactant to complete the combustion while avoiding locally high temperatures, and thus thermal NOx formation. A ring of jet nozzles (42) radially injects relatively small amounts of high pressure gaseous reactant or steam to form a throat to separate and stabilize the vortices. Alternatively, the pipes extending between the two cavities can include a convergent and divergent portion forming the throat. <IMAGE> |
