Self-cooled oxygen-fuel burner for use in high-temperature and high-particulate furnaces

Method of combustion of a fuel comprising:

• a) introducing a fuel and an oxidant into a burner block, the burner block having a fuel conduit, the fuel conduit having an inlet and an outlet, the outlet of the fuel conduit opening into a substantially conical oxidant expansion chamber, the burner block further having a substantially annular oxidant passage, the fuel conduit positioned within the substantially annular oxidant passage, the substantially annular oxidant passage having an inlet end proximate the fuel inlet and an outlet end proximate the fuel conduit outlet, and having positioned therein at least one swirler for creating a swirling oxidant flow, the substantially annular oxidant passage fluidly communicating at its outlet end with the substantially conical oxidant expansion chamber in the burner block, the substantially conical oxidant expansion chamber having an inlet diameter Ds and an outlet diameter Dc such that Dc is at least 110% of Ds, the outlet of the substantially conical oxidant expansion chamber positioned in fluid communication with a toroidal combustion chamber having an inlet and an outlet, the outlet of the toroidal combustion chamber opening to a furnace chamber, the toroidal combustion chamber having a radius of curvature R, the outlet of the fuel conduit being recessed a distance Lr from the toroidal combustion chamber outlet, where Lr=Lt+Le, where Lt=length in axial direction of the toroidal combustion chamber, and Le=length in axial direction of the substantially conical oxidant expansion chamber;
• b) forming a swirling oxidant as it passes through the swirler;
• c) flowing the swirling oxidant and the fuel into the substantially conical oxidant expansion chamber, the fuel flowing substantially near the axial center of the substantially conical oxidant expansion chamber, the swirling oxidant sweeping past a wall of the substantially conical oxidant expansion chamber;
• d) flowing the swirling oxidant and the fuel into the substantially toroidal combustion chamber;
• e) combusting the fuel and oxidant in the substantially toroidal combustion chamber while the oxidant sweeps past a wall of the substantially toroidal combustion chamber;
• f) flowing the combustion products into a furnace from the substantially toroidal combustion chamber;
• and
• g) wherein the fuel has a velocity less than or equal to 50 ft/sec.

Method of combustion of a fuel comprising:

• a) introducing a fuel and an oxidant into a burner block, the burner block having a fuel conduit, the fuel conduit having an inlet and an outlet, the outlet of the fuel conduit opening into a substantially conical oxidant expansion chamber, the burner block further having a substantially annular oxidant passage, the fuel conduit positioned within the substantially annular oxidant passage, the substantially annular oxidant passage having an inlet end proximate the fuel inlet and an outlet end proximate the fuel conduit outlet, and having positioned therein at least one swirler for creating a swirling oxidant flow, the substantially annular oxidant passage fluidly communicating at its outlet end with the substantially conical oxidant expansion chamber in the burner block, the substantially conical oxidant expansion chamber having an inlet diameter Ds and an outlet diameter Dc such that Dc is at least 110% of Ds, the outlet of the substantially conical oxidant expansion chamber positioned in fluid communication with a toroidal combustion chamber having an inlet and an outlet, the outlet of the toroidal combustion chamber opening to a furnace chamber, the toroidal combustion chamber having a radius of curvature R, the outlet of the fuel conduit being recessed a distance Lr from the toroidal combustion chamber outlet, where Lr=Lt+Le, where Lt=length in axial direction of the toroidal combustion chamber, and Le=length in axial direction of the substantially conical oxidant expansion chamber;
• b) forming a swirling oxidant as it passes through the swirler;
• c) flowing the swirling oxidant and the fuel into the substantially conical oxidant expansion chamber, the fuel flowing substantially near the axial center of the substantially conical oxidant expansion chamber, the swirling oxidant sweeping past a wall of the substantially conical oxidant expansion chamber;
• d) flowing the swirling oxidant and the fuel into the substantially toroidal combustion chamber;
• e) combusting the fuel and oxidant in the substantially toroidal combustion chamber while the oxidant sweeps past a wall of the substantially toroidal combustion chamber;
• f) flowing the combustion products into a furnace from the substantially toroidal combustion chamber;
• and
• g) wherein the oxidant has a velocity less than or equal to 300 ft/sec.