Development of a low emissions, lean premixed, natural gas burner

A novel method of aerodynamically stabilizing lean premixed natural gas flames on a conventional burner was investigated. Flames were anchored in the wake behind a small ring placed in the exit plane of a conventional burner. The overall stability regime of the burner was significantly increased, permitting stable lean premixed combustion down to equivalence ratios of 0.55. The lower flame temperatures associated with lean premixed combustion resulted in significantly reduced emissions, particularly NOx emissions which could be virtually eliminated. CO emissions were reduced at equivalence ratios down to approximately 0.75 due primarily to the excess air available for combustion. At equivalence ratios below 0.75, temperatures in the exhaust gas dropped to the point where the conversion of CO to CO...