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.

Claims data not available