Abstract: A precombustor system (300) including an ignition chamber (301) having a front wall (308), a central axis, a diameter Dic, and an outlet (313) configured to discharge a product gas (315). The ignition chamber (301) includes a central ignition oxygen injector (307) configured to inject a first oxygen stream from the front wall (308) substantially parallel to the central axis, and a tangential primary fuel injector (303) configured to inject a primary fuel stream tangential to the central axis at a location an axial distance Xpf downstream of the front wall (308). The ratio Xpf/Dic is from 0.25 to 4.0. The central axis forms an angle a with a vertical line of less than or equal to about 45 degrees. The trajectory of the primary fuel stream forms an angle ? with a plane that is perpendicular to the central axis of less than or equal to about 20 degrees. A method for combustion is also disclosed.

Abstract: A precombustor system (300) including an ignition chamber (301) having a front wall (308), a central axis, a diameter Dic, and an outlet (313) configured to discharge a product gas (315). The ignition chamber (301) includes a central ignition oxygen injector (307) configured to inject a first oxygen stream from the front wall (308) substantially parallel to the central axis, and a tangential primary fuel injector (303) configured to inject a primary fuel stream tangential to the central axis at a location an axial distance Xpf downstream of the front wall (308). The ratio Xpf/Dic is from 0.25 to 4.0. The central axis forms an angle a with a vertical line of less than or equal to about 45 degrees. The trajectory of the primary fuel stream forms an angle ? with a plane that is perpendicular to the central axis of less than or equal to about 20 degrees. A method for combustion is also disclosed.

Abstract: A solid fuel/oxygen burner including a central oxygen conduit extending toward a tip end of the burner, an outer fuel conduit surrounding the oxygen conduit, an inner fuel conduit positioned between the oxygen conduit and the outer fuel conduit to form an inner annulus in conjunction with the oxygen conduit and an outer annulus in conjunction with the outer fuel conduit, the inner fuel conduit having an outlet end upstream of the tip end, a truncated conical divider within the outer fuel conduit surrounding the oxygen conduit downstream of the inner fuel conduit for dividing a fuel stream in the outer fuel conduit into an inner annular conical diffuser and an outer annular converging nozzle, and at least three radial guide vanes within the diffuser, wherein the outlet end of the inner fuel conduit is spaced apart from an inlet end of the divider by a distance, X.

Abstract: A burner includes a first oxidant conduit to transmit a first stream of an oxidant; a solid fuel conduit having an outtake and surrounding the first oxidant conduit, thereby forming a first annulus to transmit a mixture of a transport gas and particles of a solid fuel; a second oxidant conduit surrounding the solid fuel conduit, thereby forming a second annulus to transmit a second stream of the oxidant or an other oxidant; and means for segregating the mixture proximate the outtake into a lean fraction stream and a dense fraction stream. The first stream of the oxidant exiting the first oxidant conduit combines during combustion with the lean fraction stream, thereby forming an inner combustion zone adjacent the outtake, and the second stream of the oxidant, or the other oxidant, exiting the second oxidant conduit combines during combustion with the dense fraction stream, thereby forming an outer combustion zone.

Abstract: A burner includes a first oxidant conduit to transmit a first stream of an oxidant; a solid fuel conduit having an outtake and surrounding the first oxidant conduit, thereby forming a first annulus to transmit a mixture of a transport gas and particles of a solid fuel; a second oxidant conduit surrounding the solid fuel conduit, thereby forming a second annulus to transmit a second stream of the oxidant or an other oxidant; and means for segregating the mixture proximate the outtake into a lean fraction stream and a dense fraction stream. The first stream of the oxidant exiting the first oxidant conduit combines during combustion with the lean fraction stream, thereby forming an inner combustion zone adjacent the outtake, and the second stream of the oxidant, or the other oxidant, exiting the second oxidant conduit combines during combustion with the dense fraction stream, thereby forming an outer combustion zone.

Abstract: A method for operating a cyclone combustor having first and second burners in communication with a barrel includes: feeding a stream of a primary fuel and a primary oxidant having a first oxygen concentration into the first burner; feeding a stream of a secondary fuel and a secondary oxidant having a second oxygen concentration greater than or equal to the first oxygen concentration into the second burner; combusting at least a portion of the primary fuel with at least a portion of the primary oxidant in the barrel of the cyclone combustor, thereby forming a plurality of primary products of combustion in the barrel; and combusting at least a portion of the secondary fuel with at least a portion of the secondary oxidant, thereby forming a plurality of secondary products of combustion and a secondary flame, the secondary flame generating a supplemental radiant heat in the barrel.

Abstract: A method for combusting a fuel in a cyclone combustor having a burner and a barrel includes: feeding a stream of the fuel into the barrel at the burner end of the barrel; feeding a stream(s) of a first oxidant (e.g., air) having a first oxygen concentration into the barrel at a first flowrate, the stream(s) of the first oxidant including a predominant stream; feeding a stream(s) of a second oxidant (e.g., oxygen) having a second oxygen concentration into the barrel at a second flowrate and in a selective manner, whereby a portion of the first oxidant combines with a portion of the second oxidant, thereby forming a combined oxidant having a combined oxygen concentration, and a portion of the first oxidant from the predominant stream continues having the first oxygen concentration; and combusting a portion of the fuel with a portion of the combined oxidant in the barrel.