Apparatus for burning pulverized solid fuels with oxygen
View Patent ↗A burner assembly combines oxygen and fuel to produce a flame. The burner assembly includes an oxygen supply tube adapted to receive a stream of oxygen and a fuel supply tube arranged to extend through the oxygen tube to convey a stream of fluidized, pulverized, solid fuel into a flame chamber. Oxygen flowing through the oxygen supply tube passes through oxygen-injection holes formed in the fuel supply tube and then mixes with fluidized, pulverized, solid fuel passing through the fuel supply tube to create an oxygen-fuel mixture in a downstream portion of the fuel supply tube. This mixture is discharged into the flame chamber and ignited in a flame chamber to produce a flame.
1. A burner assembly for combining oxygen and fuel to produce a flame, the burner assembly comprising
a fuel supply system including a solid-fuel conduit formed to include a fuel transport passageway
mixing means for mixing a stream of oxygen with fluidized, pulverized, solid fuel conducted through the fuel transport passageway prior to combustion to produce a mixture that can be ignited in a flame chamber to produce a flame
wherein the mixing means includes an oxygen flow passage and a oxygen-fuel nozzle positioned to lie in the oxygen flow passage and formed to include an oxygen-fuel transport passageway, a fuel inlet opening located to admit fluidized, pulverized, solid fuel discharged from the fuel transport passageway into the oxygen-fuel transport passageway, and an oxygen-fuel outlet opening located to discharge an oxygen-fuel mixture into the flame chamber, and upstream oxygen-injection holes arranged to conduct oxygen flowing in the oxygen flow passage into the oxygen-fuel transport passageway to mix with fluidized, pulverized, solid fuel flowing in the oxygen-fuel transport passageway toward the oxygen-fuel outlet opening to establish a combustible oxygen-fuel mixture flowing in the oxygen-fuel transport passageway and exiting through the oxygen-fuel outlet opening, and
wherein the oxygen-fuel nozzle includes a cylindrical interior wall communicating with the fuel inlet opening and defining a first-stage portion of the oxygen-fuel transport passageway and the oxygen-fuel nozzle further includes a frustoconical interior wall extending from the cylindrical interior wall to the oxygen-fuel outlet opening to diverge in a direction toward the oxygen-fuel outlet opening and defining a second-stage portion of the oxygen-fuel transport passageway, and further comprising diverter means located in the second-stage portion for interrupting flow of the combustible oxygen-fuel mixture flowing toward the oxygen-fuel outlet opening to cause some of said mixture to flow along the frustoconical interior wall toward the oxygen-fuel outlet opening.
2. The burner assembly claim 1 , wherein the oxygen-fuel nozzle includes an outlet end face including a circular interior edge defining an annular outer boundary of the oxygen-fuel outlet opening and the diverter means includes a circular exterior edge that lies in concentric, spaced-apart relation to the circular interior edge to establish an annular shape of the oxygen-fuel outlet opening.
3. The burner assembly of claim 2 , wherein the diverter means includes an interior cone-shaped portion having an apex positioned to lie at a junction between the first-stage and second-stage portions of the oxygen-fuel transport passageway.
4. The burner assembly of claim 3 , wherein the diverter means further includes a hemisphere-shaped portion coupled to a base of the interior cone-shaped portion and arranged to lie outside of the oxygen-fuel transport passageway.
5. The burner assembly of claim 3 , wherein the diverter means further includes an exterior cone-shaped portion coupled to a base of the interior cone-shaped portion and arranged to lie outside of the oxygen-fuel transport passageway.
6. The burner assembly of claim 3 , wherein the interior cone-shaped portion includes a flat base including the cylindrical exterior edge and lying in substantially coplanar relation to the outlet end face.
7. The burner assembly of claim 1 , wherein the cylindrical interior wall is formed to include the upstream oxygen-injection holes.
8. The burner assembly of claim 7 , wherein the cylindrical interior wall is formed to include auxiliary oxygen-injection holes located in a region between the upstream oxygen-injection holes and the frustoconical interior wall.