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EP-4565821-B1 - BURNER WITH ALTERNATE MODES FOR FLEXIBLE OPERATION

EP4565821B1EP 4565821 B1EP4565821 B1EP 4565821B1EP-4565821-B1

Inventors

  • BELL, ROBERT, L.
  • KULKAMI, Gaurav

Dates

Publication Date
20260513
Application Date
20230725

Claims (16)

  1. A burner (1, 2) comprising: a central conduit (11, 23) having a central axis (12, 24) and terminating in a central outlet (13, 25) which opens into a downstream space (14, 27); a first annular conduit (15, 28) surrounding the central conduit (11, 23), the first annular conduit and the central conduit being separated by an annular wall (16, 26), wherein the first annular conduit terminates in an outlet (17, 29) which opens into said downstream space (14, 27), where in the first annular conduit comprises a nozzle plate (18) across the outlet of the first annular conduit, wherein the nozzle plate comprises a plurality of orifices (19) that extend through the nozzle plate from within the first annular conduit (15, 28) to the downstream space; wherein the central conduit (11, 23) and the first annular conduit (15, 28) are each connected to a source (35) of a first reactant through mechanism (36) with which the flow of the first reactant from the source thereof into the central conduit and the flow of the first reactant from the source thereof into the first annular conduit can be controlled; and a second annular conduit (21, 30) surrounding the first annular conduit (15, 28) and terminating in a second annular outlet (22, 31) which opens into said downstream space (14, 27), wherein the second annular conduit is connected to a source (40) of a second reactant through mechanism (41) with which the flow of the second reactant from the source thereof into the second annular conduit can be controlled; wherein one of the first and second reactants comprises fuel and the other of the first and second reactants is oxidant that comprises oxygen.
  2. Combustion apparatus comprising: a first burner (1) comprising a first central conduit (11) having a central axis (12) and terminating in a first central outlet (13) which opens into a first downstream space (14); a first annular conduit (15) surrounding the first central conduit (11), the first annular conduit and the first central conduit being separated by an annular wall (16), wherein the first annular conduit terminates in an outlet (17) which opens into said first downstream space (14), wherein the first annular conduit comprises a nozzle plate (18) across the outlet of the first annular conduit, wherein the nozzle plate comprises a plurality of orifices (19) that extend through the nozzle plate from within the first annular conduit to the first downstream space; wherein the first central conduit (11) and the first annular conduit (15) are each connected to a source (35) of a first reactant through mechanism (36) with which the flow of the first reactant from the source thereof into the first central conduit and the flow of the first reactant from the source thereof into the first annular conduit can be controlled; and a second annular conduit (21) surrounding the first annular conduit (15) and terminating in a second annular outlet (22) which opens into said first downstream space (14), wherein the second annular conduit is connected to a source (40) of a second reactant through mechanism (41) with which the flow of the second reactant from the source thereof into the second annular conduit can be controlled; and a second burner (2) comprising a second central conduit (23) having a central axis (24) and terminating in a second central outlet (25) which opens into a second downstream space (27); a third annular conduit (28) surrounding the second central conduit (23), the third annular conduit and the second central conduit being separated by an annular wall (26), wherein the third annular conduit terminates in an outlet (29) which opens into said second downstream space (27), wherein the third annular conduit comprises a nozzle plate (18) across the outlet of the third annular conduit, wherein the nozzle plate comprises a plurality of orifices (19) that extend through the nozzle plate from within the third annular conduit to the second downstream space; wherein the second central conduit (23) and the third annular conduit (28) are connected to a source (35) of said first reactant through mechanism (36) with which the flow of the first reactant from the source thereof into the second central conduit and the flow of the first reactant from the source thereof into the third annular conduit can be controlled; and a fourth annular conduit (30) surrounding the third annular conduit (28) and terminating in a fourth annular outlet (31) which opens into said second downstream space (27), wherein the fourth annular conduit is connected to a source (40) of said second reactant through mechanism (41) with which the flow of the second reactant from the source thereof into the fourth annular conduit can be controlled; wherein the central axis (11) of the first central conduit (15) is above the central axis (12) of the second central conduit (23); wherein one of the first and second reactants comprises fuel and the other of the first and second reactants is oxidant that comprises oxygen.
  3. A burner according to claim 1 or a combustion apparatus according to claim 2 wherein the first reactant comprises fuel and the second reactant comprises oxygen.
  4. Combustion apparatus according to claim 2 comprising a plurality of said first burners (1), and further comprising a plurality of said second burners (2), wherein the central axes (12) of all of said first burners are above the central axes (24) of all of said second burners.
  5. Combustion apparatus according to claim 4 wherein all of said plurality of first burners (1) lie in a first plane and all of said plurality of second burners (2) lie in a second plane that is not said first plane.
  6. A method of combustion in a furnace, comprising: providing combustion apparatus according to claim 2; feeding fuel from the first central outlet (13) and from the first annular conduit nozzle plate (18) of said first burner (1) into a first downstream space (14) within said furnace; feeding oxidant from the second annular outlet (21) of said first burner (1) into said first downstream space (14), and combusting said fuel fed from the first central outlet (13) and from the first annular conduit nozzle plate (18) with said oxidant fed from the second annular outlet (21), to create a mixture of products of said combustion in said first downstream space (14); while feeding fuel from the second central outlet (23) and from the third annular conduit nozzle plate (18) of said second burner (2) into a second downstream space (27) within said furnace; feeding oxidant from the fourth annular outlet (31) of said second burner (2) into said second downstream space (27), and combusting said fuel fed from the second central outlet (23) and from the third annular conduit nozzle plate (18) with said oxidant fed from the fourth annular outlet (31), to create a mixture of products of said combustion in said second downstream space (27); wherein said first downstream space (14) is located above said second downstream space (27).
  7. A method according to claim 6 further comprising continuously combusting said fuel fed from the nozzle plates (18) that are across the outlets (17, 29) of said first and third annular conduits (15, 28).
  8. A method of combustion in a furnace, comprising: providing combustion apparatus that comprises a plurality of first burners (1) comprisir g a first central conduit (11) having a central axis (12) and terminating in a first central outlet (13) which opens into a first downstream space (14); a first annular conduit (15) surrounding the first central conduit (11), the first annular conduit and the first central conduit being separated by an annular wall (16), wherein the first annular conduit terminates n an outlet (17) which opens into said first downstream space (14), wherein the first annular conduit comprises a nozzle plate (18) across the outlet of the first annular conduit, wherein the nozzle plate comprises a plurality of orifices (19) that extend through the nozzle plate from within the first annular conduit to the first downstream space; wherein the first central conduit (11) and the first annular conduit (15) are each connected to a source (35) of a first reactant through mechanism (36) with which the flow of the first reactant from the source thereof into the first central conduit and the flow of the first reactant from the source thereof into the first annular conduit can be controlled; and a second annular conduit (21) surrounding the first annular conduit (15) and terminating in a second annular outlet (22) which opens into said first downstream space (14), wherein the second annular conduit is connected to a source (40) of a second reactant through mechanism (41) with which the flow of the second reactant from the source thereof into the second annular conduit can be controlled; and a plurality of second burners (2) comprising a second central conduit (23) having a central axis (24) and terminating in a second central outlet (25) which opens into a second downstream space (27); a third annular conduit (28) surrounding the second central conduit (23), the third annular conduit and the second central conduit being separated by an annular wall (26), wherein the third annular conduit terminates in an outlet (29) which opens into said second downstream space (27), wherein the third annular conduit comprises a nozzle plate (18) across the outlet of the third annular conduit, wherein the nozzle plate comprises a plurality of orifices (19) that extend through the nozzle plate from within the third annular conduit to the second downstream space; wherein the second central conduit (23) and the third annular conduit (28) are connected to a source (35) of said first reactant through mechanism (36) with which the flow of the first reactant from the source thereof into the second central conduit and the flow of the first reactant from the source thereof into the third annular conduit can be controlled; and a fourth annular conduit (30) surrounding the third annular conduit (28) and terminating in a fourth annular outlet (31) which opens into said second downstream space (27), wherein the fourth annular conduit is connected to a source (40) of said second reactant through mechanism (41) with which the flow of the second reactant from the source thereof into the fourth annular conduit can be controlled; wherein the central axes (11) of all of said first burners (1) are above the central axes (24) of all of said second burners (2); wherein one of the first and second reactants comprises fuel and the other of the first and second reactants is oxidant that comprises oxygen; feeding fuel from the first central outlets (13) and from the first annular conduit nozzle plates (18) of each of said first burners (1) into a first downstream space (14) within said furnace; feeding oxidant from the second annular outlets (22) of each of said first burners (1) into said first downstream space (14), and combusting said fuel fed from the first central outlets (13) and from the first annular conduit nozzle plates (18) with said oxidant fed from the second annular outlets (22), to create a mixture of products of said combustion which pass into said first downstream space (14); while feeding fuel from the second central outlets (25) and from the third annular conduit nozzle plates (18) of each of said second burners (2) into a second downstream space (27) within said furnace; feeding oxidant from the fourth annular outlets (31) of each of said second burners (2) into said second downstream space (27), and combusting said fuel fed from the second central outlets (25) and from the third annular conduit nozzle plates (18) with said oxidant fed from the fourth annular outlets (31), to create a mixture of products of said combustion which pass into said second downstream space (27).
  9. A method according to claim 8 further comprising continuously combusting said fuel fed from the nozzle plates (18) that are across the outlets (19) of each of said first and third annular conduits (15, 28).
  10. A method according to claim 8 wherein all of said plurality of first burners (1) lie in a first plane and all of said plurality of second burners (2) lie in a second plane that is not said first plane, and said first plane is above said second plane.
  11. Combustion apparatus according to claim 5 or method according to claim 10 wherein one or both of said first and second planes is horizontal.
  12. Combustion apparatus according to claim 5 or method according to claim 10 wherein said first and second planes ir tersect.
  13. A method according to claim 8 wherein the mixture of products of combustion which pass into one of said first downstream space (14) and said second downstream space (27) is fuel-rich and the mixture of products of combustion which pass into the other of said first downstream space and said second downstream space is fuel-lean.
  14. A method according to claim 13 wherein alternatingly (A) the mixture of products of combustion which pass into said first downstream space (14) is fuel-rich and the mixture of products of combustion wh ch pass into said second downstream space (27) is fuel-lean, and (B) the mixture of products of combustion which pass into said first downstream space is fuel-lean and the mixture of products of combustion which pass into said second downstream space is fuel-rich.
  15. A method according to claims 6, 9, 10, 13 or 14 wherein said furnace contains a bath of molten glass.
  16. A method according to claim 14 wherein said furnace contains a bath of molten glass and which alternates between (A) and (B) in response to a detected characteristic of said bath of molten glass.

Description

Field of the Invention The present invention relates to combustion in industrial furnaces such as furnaces that are used in the production of glass. Background of the Invention The manufacture of glass products typically involves melting a mixture of glassmaking ingredients in a glassmelting furnace to produce molten glass which is then treated and formed into the desired glass products. Typical glassmaking ingredients (which can be used as well in the practice of this invention) include oxides, hydroxides, silicates and sulfates of sodium and potassium, and mixtures thereof, and crushed and broken pieces of glass. The heat for melting the glassmaking ingredients in the furnace is often provided by combustion of fuel inside the furnace, often at burners situated in one or more walls of the furnace that generate flames which extend from the burner into the interior of the furnace. Unfortunately, the melting operations of this type have been known to cause formation of a layer of bubbles, usually referred to as form, on the surface of the molten glass. This foam is undesirable as it interferes with achieving efficient heat exchange in the furnace from the flames to the glassmaking ingredients and to the bath of molten glass. The foam can also degrade the quality of the molten glass. The present invention provides useful ability to minimize or prevent formation of foam on the surface of a bath of molten glass. The present invention also provides reduced formation of undesired combustion byproducts such as nitrogen oxides ("NOx"). Burners used in furnaces such as (but not limited to) glassmelting furnaces can also suffer from fouling or plugging of ports in the furnace walls through which combustion reactants are desired to be fed. The present invention also provides effective ability to limit or avoid this fouling and plugging. US 5 957 678 A discloses a combustion detoxifying apparatus comprising a combustion chamber; and a multi-wall pipe burner having a raw gas nozzle for injecting raw gas containing toxic components, a lift gas nozzle for injecting inert gas formed, a raw gas combustion assisting gas nozzle for injecting a gas for assisting combustion of combustible components in the raw gas, a fuel gas combustion assisting gas nozzle for injecting a gas for assisting combustion of the fuel gas, and a fuel gas nozzle for injecting fuel gas. US 2011/000261 A1 discloses a burner which is recessed from a combustion space in a burner block adjacent the combustion space. The burner is configured to inject a first reactant, one of fuel and an oxidant, from an inner body, and a second reactant, the other one of fuel and oxidant, through a continuous annulus or a plurality of radially spaced holes formed in an outer body that surrounds the inner body. Brief Summary of the Invention One aspect of the present invention is a burner comprising: a central conduit having a central axis and terminating in a central outlet which opens into a downstream space;a first annular conduit surrounding the central conduit, the first annular conduit and the central conduit being separated by an annular wall, wherein the first annular conduit terminates in an outlet which opens into said downstream space, wherein the first annular conduit comprises a nozzle plate across the outlet of the first annular conduit, wherein the nozzle plate comprises a plurality of orifices that extend through the nozzle plate from within the first annular conduit to the downstream space;wherein the central conduit and the first annular conduit are each connected to a source of a first reactant through mechanism with which the flow of the first reactant from the source thereof into the central conduit and the flow of the first reactant from the source thereof into the first annular conduit can be controlled; anda second annular conduit surrounding the first annular conduit and terminating in a second annular outlet which opens into said downstream space, wherein the second annular conduit is connected to a source of a second reactant through mechanism with which the flow of the second reactant from the source thereof into the second annular conduit can be controlled;wherein one of the first and second reactants comprises fuel and the other of the first and second reactants is oxidant that comprises oxygen. Another aspect of the present invention is combustion apparatus comprising: a first burner comprisinga first central conduit having a central axis and terminating in a first central outlet which opens into a first downstream space;a first annular conduit surrounding the first central conduit, the first annular conduit and the first central conduit being separated by an annular wall, wherein the first annular conduit terminates in an outlet which opens into said first downstream space, wherein the first annular conduit comprises a nozzle plate across the outlet of the first annular conduit, wherein the nozzle plate comprises a plurality of orifices that