Kissing arrangement for a burner, as well as a burner with such a kissing arrangement

Description

1 / 23 “ARRANGEMENT OF NOZZLES FOR A BURNER, AS WELL AS A BURNER WITH SUCH AN ARRANGEMENT OF NOZZLES”

[0001] This patent application claims priority over German patent application DE 10 2023 202 662.7, the content of which is incorporated herein by reference.

[0002] The invention relates to a burner device for an asphalt production plant, a plant with such a burner device, as well as a method for supplying heat to a rotary tubular kiln of a burner device.

[0003] In an asphalt production plant, various materials are processed, in particular heated, dried, and / or mixed with each other. A large portion of the energy application required for the subsequent asphalt mixing process is used to dry the materials during asphalt production. The materials are heated during drying. The temperature can reach up to 450 °C, depending on the type of asphalt to be mixed and, in particular, the proportion of asphalt granules to be mixed, also known as recycled material, to be added. Drying takes place in a rotary tubular kiln, also known as a drying drum. Heat is supplied to the rotary tubular kiln, generated by a separate heating unit. Heat generation is generally based on the combustion of fossil fuels such as natural gas, liquefied petroleum gas, heating oil, and / or coal dust. The combustion of fossil fuels is problematic from a climate standpoint.

[0004] Other non-fossil combustible gases, such as hydrogen, have a high reaction rate and lead to high flame temperatures, so conventional burners cannot simply be used for the combustion of these combustible gases.

[0005] The objective of the present invention is to improve the heat supply and its orientation within a rotary tubular furnace during the production of Petition 870250086011, dated 09 / 23 / 2025, page 9 / 118 2 / 23 asphalt, particularly from a technical-climatic perspective and, in particular, with an uncomplicated design.

[0006] This objective is achieved according to the invention by a burner device with the characteristics specified in claim 1, by an installation with the characteristics specified in claim 9, as well as by a method with the characteristics specified in claim 10.

[0007] According to the invention, it has been observed that a fuel gas can be burned efficiently and directly in a burner to generate heat if secondary gas is additionally directed to the burner. The fuel gas, in particular hydrogen and / or acetylene, has a comparatively high reaction rate, so that high flame temperatures, particularly with local temperature peaks, can occur during the combustion of the fuel gas alone. However, during the combustion of the secondary gas, the combustion reaction rate in the burner can be specifically reduced. This means that the combustion reaction in the burner is slowed down by the addition of the secondary gas.

[0008] In particular, the fuel gas nozzle and the secondary gas nozzle are arranged in such a way that the orientation of the fuel gas and the secondary gas occurs separately from the orientation of air within the combustion chamber. In particular, the fuel gas and the secondary gas are oriented together within the combustion chamber, but separately from the air. In particular, a mixture of fuel gas and secondary gas is generated and this mixture is oriented to the combustion chamber by means of the nozzle arrangement, where mixing with air occurs. In particular, a mixture of air with fuel gas and secondary gas occurs only in the combustion chamber. In the nozzle arrangement there is no mixing of fuel gas with air. In particular, there is no air orientation within the nozzle arrangement.

[0009] In particular, the mixing of fuel gas and secondary gas occurs in the absence of air. Then, the mixture of fuel gas and secondary gas is mixed with air in the combustion chamber. Petition 870250086011, dated 09 / 23 / 2025, p. 10 / 118 3 / 23

[0010] Hydrogen has a flame temperature in air of 2,130 °C. Nitrogen oxides are formed at a combustion temperature of about 1400 °C, where their quantity increases exponentially as temperatures continue to rise.

[0011] In particular, the fuel gas is processed as primary fuel gas, secondary gas, and air in the burner. In particular, the secondary gas is different from air. In particular, the secondary gas is air-free. Optionally, a secondary fuel gas may be added and burned together. It is important that only gases are processed in the burner. The burner is specifically a gas burner. Liquids and / or solids as fuels are not processed in the burner according to the invention.

[0012] According to the invention, it has been observed that this reduces fuel conversion by volume. This reduces and, in particular, avoids high-temperature zones in the burner. By reducing high-temperature zones, the combustion reaction is gentler on the burner. The burner's lifespan is increased. The burner device according to the invention is ecologically and economically advantageous. In particular, it has been observed that these high-temperature zones are one of the main causes of nitrogen oxide (NOx) emissions. By reducing nitrogen oxide emissions, the method according to the invention is environmentally friendly. In particular, the formation of nitrogen oxides can be directly avoided during combustion.

[0013] According to the invention, heat is generated, at least partially, and in particular, exclusively by the combustion of hydrogen gas as fuel gas. The combustion of hydrogen gas is carbon dioxide-free. When hydrogen gas is burned, no carbon dioxide is produced. The combustion of hydrogen gas is environmentally beneficial. Exhaust gases and / or harmful emissions are reduced. It is particularly advantageous if the hydrogen gas has been produced from renewable energy sources, i.e., if it is so-called green hydrogen.

[0014] The burner is used to direct heat to a rotary tubular furnace. Petition 870250086011, dated 09 / 23 / 2025, page 11 / 118 4 / 23 For this purpose, the burner is coupled to the rotary tubular furnace. A flame generated from combustion by the burner can burn directly in the rotary tubular furnace. In this case, the burner and the rotary tubular furnace are physically coupled to each other. Alternatively, the burner flame can burn spatially away from the rotary tubular furnace, in particular in a hot gas generator. The heat generated in this way can be guided as hot gas from the hot gas generator to the rotary tubular furnace. The heat generated by the burner is guided to the rotary tubular furnace as hot gas. In this case, the burner is indirectly coupled to the rotary tubular furnace, in particular by a hot gas line.

[0015] The burner has a suction chamber to draw air, in particular ambient air, into the burner compartment. In particular, an air line is connected to the burner to supply air, in particular ambient air. This allows a mixture of fuel gas and combustion air to be created in the burner to improve the combustion of the fuel gas.

[0016] An exhaust gas recirculation line according to claim 2 allows for an uncomplicated supply of secondary gas. In particular, it has been observed that the exhaust gases from the burner device can be advantageously used to retard the combustion reaction.

[0017] A burner device according to claim 3 allows the integration of different exhaust gas sources. The rotary tubular furnace itself can serve as an exhaust gas source for exhaust gas recirculation. In particular, the exhaust gases from the rotary tubular furnace are returned directly to the burner via the exhaust gas recirculation line. Additionally or alternatively, at least one other exhaust gas source may be present from which the exhaust gases are fed to the burner. The at least one other exhaust gas source is, in particular, another rotary tubular furnace, a bucket conveyor, a Petition 870250086011, dated 09 / 23 / 2025, page 12 / 118 5 / 23 chimney and / or a filter unit, in particular a filter dust removal unit. In particular, there may be several exhaust gas recirculation lines running from different exhaust gas sources to the burner. In particular, an exhaust gas recirculation line system is present, to which the rotary tubular furnace and / or at least one other exhaust gas source are fluidically connected, in particular, at least indirectly, to the burner.

[0018] An exhaust gas purification unit according to claim 4 ensures that the recirculated exhaust gas has a reduced dust content. In particular, the exhaust gas is dust-free, meaning that it substantially does not contain dust particles. The exhaust gas is, in particular, smoke gas in which the dust particle ratio is less than 20 mg / m3 and, in particular, less than 10 mg / m3. It has been innovatively concluded that purified exhaust gases, and especially smoke gases, are particularly advantageous for retarding the combustion reaction.

[0019] Alternatively, it is possible to allow at least a partial dust load in the exhaust gases. In particular, the dust load is less than 35 mg / m3.

[0020] A natural gas line according to claim 5 allows for the directed flow of inert gas to the burner. It has been concluded, according to the invention, that the combustion reaction in the burner can be deliberately retarded by using inert gas. Inert gases are gases that have a higher inert ratio than ambient air. Examples of inert gases that can be considered are nitrogen, water vapor, or noble gases such as helium, neon, argon, krypton, xenon, and / or radon.

[0021] In particular, the inert gas line is connected to a source of inert gas, in particular an inert gas storage vessel.

[0022] A mixing chamber according to claim 6 improves the combustion process. The mixing chamber is used to mix fuel gas and by-gas. The mixing chamber is arranged, in particular, to Petition 870250086011, dated 09 / 23 / 2025, p. 13 / 118 6 / 23 burner assembly and / or integrated into or within the burner, in particular in a nozzle and, in particular, in a combination of nozzles. The mixing chamber allows for pre-mixing of the fuel gas with the secondary gas, in particular before the fuel gas is mixed with air in the burner. The risk of an unwanted and uncontrolled increase in flame temperature, for example, because the fuel gas is unintentionally burned and undiluted in the burner, is reduced and, in particular, eliminated.

[0023] Alternatively, it is possible to direct each of the fuel gas and the secondary gas separately to the burner. In particular, it is advantageous for the fuel gas and secondary gas to be directed in a targeted manner, so that only the fuel gas undergoes undesirable combustion, i.e., without the retarding effect of the secondary gas. By directing and separating the fuel gas and secondary gas, the combustion reaction can be retarded.

[0024] A burner device according to claim 7 simplifies the controlled retardation of fuel gas combustion. By directing secondary gas to the mixing chamber and mixing it with the fuel gas, unwanted temperature peaks can be avoided.

[0025] A burner device according to claim 8 makes it possible to avoid unwanted combustion, in particular undesirably premature combustion, of the fuel gas. As the air is guided through the mixing chamber and directed only downstream in the combustion chamber, combustion of the fuel gas in the mixing chamber is eliminated.

[0026] An installation according to claim 9 has the advantages of the burner device, which is referred to in this document.

[0027] A method according to claim 10 ensures the efficient and advantageous combustion of a combustible gas.

[0028] Both the features specified in the patent claims and the features specified in the following embodiment of a burner device according to the invention are respectively Petition 870250086011, dated 09 / 23 / 2025, p. 14 / 118 7 / 23 suitable, individually or in combination with each other, for the development of the object of the invention. The respective combinations of features do not represent any restriction as to the developments of the object of the invention, and are substantially of a merely illustrative nature.

[0029] Additional features, advantageous embodiments and details of the invention will become apparent from the following description of an exemplary embodiment with reference to the drawing. The following are shown: Figure 1 shows a schematic sketch of an asphalt production plant with a burner device according to the invention. Figure 2 shows a schematic cross-sectional view of a rotary tubular furnace with a burner as shown in Figure 1. In Figure 3, a view along the cutting line 111-111 in Figure 2, In Figure 4, a detailed enlarged view of detail IV in Figure 2, Figure 5 shows a detailed, enlarged perspective view of a nozzle arrangement as per Figure 4.

[0030] An installation indicated as a whole with 1 in Figure 1 serves to produce asphalt. Installation 1 comprises a first device 2 and a second device 3, each of which is connected by an emission line 4 to a filter dust removal system 5, in particular common.

[0031] Installation 1 may also have only one device 2, 3 or more than two devices 2, 3. It is conceivable that one or more devices 2, 3 are connected to the filter dust collection system 5 by a common emission line 4. In particular, the filter dust collection system 5 is a central filter dust collection system of installation 1, in which several, and in particular all, devices 2, 3 of installation 1 are connected to the filter dust collection system 5. It is also conceivable that each device 2, 3 is assigned and connected to a separate filter dust collection system 5.

[0032] A condensate separator 6 is optionally connected to the filter dust removal system 5 and is connected to a chimney 8 by means of a blower 7. As shown in Figure 1, the condensate separator 6 can be Petition 870250086011, dated 09 / 23 / 2025, page 15 / 118 8 / 23 is located behind the filter dust removal system 5 and, additionally or alternatively, also in front of the filter dust removal system 5. In particular, in addition to the condensate separator 6, there is a recovery unit, not shown, which serves to recover the process heat that is generated, in particular, in the condensate separator 6. For this purpose, the recovery unit can be arranged, in particular, integrated into the condensate separator 6.

[0033] It has been observed that condensate separator 6 can be advantageously used in installation 1 if the exhaust air from devices 2, 3 is comparatively clean, i.e., has a reduced emission load and, in particular, is less polluted with emissions than the exhaust air from a burner burning fossil fuels.

[0034] Alternatively, it is possible that installation 1 is designed without dust removal from filter 5. In this case, devices 2, 3 are connected directly to the condensate separator 6. It is also conceivable that several condensate separators 6 are present, in particular one condensate separator 6 for each device 2, 3.

[0035] The first device 2 comprises a rotary tubular furnace 9 in which the material is dried. The rotary tubular furnace 9 has a material inlet 10 and a material outlet 11. According to the exemplary embodiment, the material inlet 10 and the material outlet 11 are each located on the end face, in particular opposite each other, of the rotary tubular furnace 9.

[0036] A burner 12 is coupled to the rotary tubular furnace 9. The burner 12 is designed to burn hydrogen gas as fuel gas and to generate a burner flame 13 which is disposed, at least in part, in the rotary tubular furnace 9. The burner 12 is a hydrogen burner. The fuel gas forms, in particular, a primary fuel. The primary fuel serves primarily, i.e., mainly, as fuel for heat generation in the burner 12. In particular, hydrogen is burned. Petition 870250086011, dated 09 / 23 / 2025, page 16 / 118 9 / 23 exclusively for heat generation in burner 12. A fuel gas line 14 is connected to burner 12, which is connected, in particular, to a fuel gas reservoir 15. The fuel gas reservoir 15 is, in particular, a storage container, in particular a storage tank, in which fuel gas, i.e. hydrogen, in particular in gaseous form, is stored. The fuel gas reservoir 15 may also be designed by means of a connection to a fuel gas supply network.

[0037] A section of the fuel gas line 14 is connected to a fuel gas distribution chamber 17 of the burner 12 by means of a compensator 16. The fuel gas distribution chamber 17 forms a fuel gas distribution mechanism. Other embodiments of the fuel gas distribution mechanism are also possible, for example, a pipe, a distribution element or a manifold. The compensator 16 is a flexible compensation element. The compensator 16 serves to compensate for movements of the fuel gas line 14, in particular as a result of thermal changes in length, vibrations, wall penetrations and / or sedimentation phenomena. The compensator 16 is arranged in a flange connection 18 between the fuel gas distribution chamber 17 and the fuel gas line 14.

[0038] An air line 19 is connected to the burner 12 to supply air, in particular ambient air.

[0039] A material transport direction 20 through the rotary tubular furnace 9 is directed from the material inlet 10 to the material outlet 11 and is oriented from right to left, according to Figure 1. A gas transport direction 21 through the rotary tubular furnace 9 is directed from the burner 12 to the emission line 4, i.e., from left to right, according to Figure 1. The material transport direction 20 and the gas transport direction 21 are oriented opposite to each other. The rotary tubular furnace 9 is operated in a countercurrent method. The tubular furnace Petition 870250086011, dated 09 / 23 / 2025, page 17 / 118 The 10 / 23 rotary 9 can also be operated using direct current.

[0040] A secondary fuel line 22 can be connected to the burner 12 to supply secondary fuel to the burner 12. These serve as secondary fuels, in particular, fossil fuel sources such as natural gas, liquefied petroleum gas, heating oil, coal, in particular coal dust, synthetic fuels (BtL) and / or wood dust. The secondary fuel line 22 is fed from a secondary fuel reservoir not shown. The secondary fuel reservoir can be designed – similarly to the fuel gas reservoir 15 – as a storage container and / or as a supply network.

[0041] The burner 12 is connected to the secondary fuel line 22 and to the gas control section via a secondary fuel distribution chamber 23 by means of a compensator 16. The compensator 16 is designed substantially identically to the compensator 16 in the fuel gas line 14 and is disposed of in a corresponding location between the secondary fuel line 22 and the secondary fuel distribution chamber 23.

[0042] The first device 2 also has an exhaust gas recirculation line 24 which is connected to the burner 12. The exhaust gas recirculation line 24, in particular a branch not shown, can also be connected directly to the rotary tubular furnace 9. The exhaust gas recirculation line 24 serves to recirculate the exhaust gases to the burner 12. The exhaust gas recirculation line 24 serves, in particular, for the internal recirculation of exhaust gases from the rotary tubular furnace 9. The exhaust gas recirculation line 24 is connected directly to the chimney 8. The exhaust gases, in particular the smoke gases, are returned to the burner 12 through the exhaust gas recirculation line 24. In addition, there may be an exhaust gas bypass line 25, with which the emission line 4 is connected directly to the exhaust gas recirculation line 24. The exhaust gases laden with dust Petition 870250086011, dated 09 / 23 / 2025, page 18 / 118 11 / 23 can be fed to burner 12 via exhaust gas bypass line 25.

[0043] Installation 1 may have additional exhaust gas sources 26, such as filter elements, for example. These additional exhaust gas sources may be connected directly to the exhaust gas recirculation line 24 by means of an exhaust gas bypass line 25. Alternatively, the exhaust gas sources 26 may be connected to the filter dust removal system 5 by means of an emission line 4. This makes it possible to supply purified exhaust gas from at least one exhaust gas source 26 to the burner 12.

[0044] A separate fan 27 is arranged in the exhaust gas recirculation line 24 to improve the direction of the exhaust gases to the burner 12. One or more flaps 28 may be arranged along the exhaust gas recirculation line 24 to control, in a targeted manner, the flow of exhaust gases and, in particular, to adjust the quantities of exhaust gases added in a targeted manner. Additionally or alternatively, control of the exhaust gas flow may also be achieved with the fan 27 and, in particular, by means of a frequency converter connected to it.

[0045] According to the exemplary embodiment shown, the exhaust gas recirculation line 24 is designed to be branched, wherein a first branch leads directly to the rotary tubular furnace 9. Another branch of the exhaust gas recirculation line 24 leads to the burner 12.

[0046] The rotary tubular furnace 9 is designed to be driven by rotation around a rotation axis 29. The drives required for this purpose, in particular the rotary drives, are known for themselves and are not shown in the figures for clarity.

[0047] The rotary tubular furnace 9 has a combustion zone 30 that extends along the axis of rotation 29 in the region of the burner flame 13. The rotary tubular furnace 9 also has a heat transfer region 31 in which Petition 870250086011, dated 09 / 23 / 2025, page 19 / 118 12 / 23 Heat transfer to the material occurs by convection.

[0048] The second device 3 is constructed substantially identically to the first device 2, which is referred to in this document. One difference is that the second device 3 comprises, in addition to the burner 12, a hot gas generator 32. The hot gas generator 32 is connected to the rotary tubular furnace 9 by means of a hot gas line 33. The hot gas generator 32 is disposed between the burner 12 and the rotary tubular furnace 9. In the second device 3, the burner 12 is designed separately from the rotary tubular furnace 9. In particular, the burner 12 is disposed completely outside the rotary tubular furnace 9. Correspondingly, the flame of the burner 13 is disposed inside the hot gas generator 32. The flame of the burner 13 is disposed outside the rotary tubular furnace 9 of the second device 3.

[0049] In the second device 3, air recirculation fans and / or air exhaust fans, not shown in detail, may be used for air direction, in particular within the rotary tubular furnace 9 and / or the hot gas generator 32. The fans are arranged, in particular, outside the rotary tubular furnace 9 and / or outside the hot gas generator 32, in particular along the connection lines. Correspondingly, the combustion zone 30 in the rotary tubular furnace 9 of the second device 3 is not required. The rotary tubular furnace 9 of the second device 3 comprises substantially and exclusively a heat transfer region 31.

[0050] Correspondingly, an exhaust gas recirculation line 24 is present from chimney 8 to burner 12 of the second device 3. According to the exemplary embodiment shown, the exhaust gas recirculation line 24 to the second device 3 is designed separately from the exhaust gas recirculation line 24 to the first device 2. It is also possible to implement a common exhaust gas recirculation line 24 with corresponding branches. Correspondingly, exhaust gas diversion lines 25 in the recirculation line. Petition 870250086011, dated 09 / 23 / 2025, page 20 / 118 13 / 23 of exhaust gases 24 can be connected to the second device 3. In particular, the rotary tubular furnace 9 of one device can represent an additional source of exhaust gas for the other device, respectively.

[0051] In the exemplary embodiment shown, each device 2, 3 has its own separate fuel gas reservoir 15. It is possible that, in installation 1, a common fuel gas reservoir 15, centrally located, is available, in fluid communication with several and, in particular, with all the burners 12 of installation 1.

[0052] Installation 1 therefore has a central inert gas reservoir 34, which is also called the inert gas source. The inert gas is stored in the inert gas reservoir 34. In particular, the inert gas has a higher inert ratio than ambient air. Nitrogen, in particular, serves as the inert gas. The inert gas reservoir 34 is connected to the burners 12 of the first device 2 and the second device 3, respectively, by an inert gas line 35. It is understood that a separate inert gas reservoir 34 can also be designed for each burner 12. This makes it possible, in particular, to supply different inert gases to the respective burner 12.

[0053] The exhaust gas recirculation line 24 and the inert gas line 35 each form a secondary gas line to supply secondary gas to the burner 12. Secondary gas, within the meaning of the invention, may be exhaust gas, in particular purified exhaust gas, and / or inert gas. The secondary gas may be used to specifically influence, in particular slow down, a combustion reaction in the burner 12.

[0054] Burner 12 has a mixing chamber 36 which is arranged so as to be integrated into burner 12. The mixing chamber 36 is used to mix the fuel gas with the secondary gas. The mixing chamber 36 is arranged, in particular, so that the fuel gas is first mixed with the secondary gas before air is supplied by the air line 19. In particular, the fuel gas line 14 and the exhaust gas recirculation line 24 and / or the inert gas line 35 are fluidically connected to the chamber. Petition 870250086011, dated 09 / 23 / 2025, p. 21 / 118 14 / 23 of mixing 36. It is also conceivable that the mixing chamber is disposed outside the burner 12, in particular adjacent to the burner 12. The mixing chamber 36 can also be disposed externally and away from the burner 12 and, in particular, upstream of the burner 12. It is possible to mix fuel gas and secondary gas separately before directing them to the burner 12.

[0055] The structure and function of the first device 2, in particular the burner 12, are explained in more detail below with reference to Figure 2.

[0056] Burner 12 has a burner compartment 38 with a longitudinal axis 37. The burner compartment 38 has a suction chamber 39 at one end facing away from the rotary kiln 9, through which air, in particular ambient air, is drawn into the burner compartment 38. For this purpose, an air line 19 and / or a silencer may be connected to the suction chamber 39. An air blower 40 is arranged along the burner compartment 38, which, according to the exemplary embodiment shown, is designed as an axial blower. It is understood that the air blower 40 may also be designed in the manner of another type of blower, in particular as a radial blower.

[0057] Burner 12 has, in particular, a flame sensor 41 that serves to monitor the flame of burner 13. In particular, several flame sensors 41 may be designed in burner 12 and, in particular, arranged apart from each other in the burner compartment 38, in particular along the longitudinal axis 37. In the burner compartment 38 there is also an ignition burner 42 that serves to ignite the flame of burner 13.

[0058] The fuel gas line 14 is connected to the burner compartment 38 through the fuel gas distribution chamber 17. The fuel gas distribution chamber 17 is arranged in a ring around the burner compartment 38. At least one fuel gas nozzle 43 is connected to the fuel gas distribution chamber 17 to supply the gas. Petition 870250086011, dated 09 / 23 / 2025, p. 22 / 118 15 / 23 fuel is directed to the burner compartment 38. In particular, several fuel gas nozzles 43 are present.

[0059] Correspondingly, at least one, and in particular several, secondary fuel nozzles 44 are connected to the secondary fuel distribution chamber 23. The secondary fuel nozzles 44 may be designed as gas lances and, in particular, may be arranged adjacent to the fuel gas nozzles 43 in the burner compartment 38.

[0060] The secondary gas lines, namely the exhaust gas recirculation line 24 and / or the inert gas line 35, are connected to a secondary gas distribution chamber 45 of the burner 12. The secondary gas distribution chamber 45 forms a secondary gas distribution mechanism and is designed analogously to the fuel gas distribution chamber 17, which is referred to in this document. The secondary gas distribution chamber 45 extends, in particular, in an annular shape around the burner compartment 38.At least one, and in particular several, secondary gas nozzles 46 are connected to the secondary gas distribution chamber 45, which serve for the directed release of secondary gas into the burner compartment 38.

[0061] At least one fuel gas nozzle 43 and at least one secondary gas nozzle 46 form a nozzle arrangement 47, which is shown in a purely schematic and simplified way in Figure 2.

[0062] In the region of the nozzle arrangement 47, in particular upstream of the nozzle arrangement 47, a vortex element 48, also shown in a purely schematic manner, is arranged in the burner compartment 38. The vortex element 48 serves to rotate the air tangentially. The vortex element 48 is designed, in particular, as a deflector plate, which has, in particular, a guide wheel. Depending on the fuel combination used, i.e., in particular, depending on the secondary fuel, in particular a secondary fuel gas, the vortex element 48 may be designed differently in diameter, shape and / or structural details. Petition 870250086011, dated 09 / 23 / 2025, p. 23 / 118 16 / 23

[0063] It is also conceivable to arrange the nozzle arrangement 47 upstream of the vortex element 48 and / or to arrange individual nozzles 43, 46 upstream and / or downstream of the vortex element 48.

[0064] The vortex element 48 is arranged in a cooling cone 49 of the burner 12. According to the exemplary embodiment shown, the cooling cone 49 has a cylindrical section whose outer diameter is at least 80% of the inner diameter of the burner compartment 38 at that point. In particular, the outer diameter of the cooling cone 49 is at least 85%, in particular at least 90%, in particular at least 95%, and in particular at most 99% of the inner diameter of the burner compartment 38 at that point. The cooling cone 49 is arranged, in particular, in a region of the burner compartment 38 where the burner compartment 38 widens conically. The burner compartment 38 has an expansion section 50 that merges into a cylindrical end section 51. The end section 51 and the expansion section 50 form a burner head 52.An annular slit 53, designed to be circumferential, in particular conical, is formed between an outer wall of the cooling cone 49 and an inner wall of the burner head 52. The air flowing through this annular slit 53 is called secondary air. Thus, secondary air flows through the cooling cone 49. The air flowing centrally through the cooling cone 49 is called primary air. Since at least some of the air flows around the cooling cone 49 as secondary air, air gradation is possible.

[0065] In the embodiment shown, the burner head 52 improves the mixing of combustion gases, in particular hydrogen with air. The flame of burner 13 is formed after the burner head 52, so the shape of the burner flame is influenced by the geometry of the burner head. This means that the shape of the burner flame 13 can be specifically adjusted by a suitable choice of burner head geometry. In particular, a flame diameter DF of burner 13 is larger Petition 870250086011, dated 09 / 23 / 2025, page 24 / 118 17 / 23 the larger the diameter at the burner head outlet 52.

[0066] Burner 12 is fixed to a front wall 54 of the rotary tubular furnace 9. The front wall 54 is called the outlet front wall because the material outlet 11 is located in that region. Burner 12, in particular burner compartment 38, is fixed to the front wall 54 by means of fasteners not shown in detail.

[0067] The front wall 54 is arranged overlapping, in the axial direction and / or in a radial direction with respect to the axis of rotation 29, in the rotary tubular furnace 9. The front wall 54 forms a cover for a cylindrical opening of the rotary tubular furnace 9. In particular, the rotary tubular furnace 9 is not hermetically sealed by the front wall 54. A circumferential gap 55 remains between the front wall 54 and the rotary tubular furnace 9. The circumferential gap 55 allows an additional supply of air, in particular ambient air, into the rotary tubular furnace 9.

[0068] Burner 12 is arranged in the rotary tubular furnace 9 in such a particular way that its longitudinal axis 37 and the axis of rotation 29 of the rotary tubular furnace 9 coincide, that is, they are identical. Burner 12 is arranged concentrically to the rotary tubular furnace 9. Burner 12 is directly fixed to the rotary tubular furnace 9 and integrated into it, at least in part. In particular, the head of burner 52 and the flame of burner 13, generated by burner 12, are arranged, in particular completely, in the rotary tubular furnace 9.

[0069] Burner 12 has a burner frame 56 with which the burner 12 is positioned underground. According to the exemplary embodiment shown, the burner frame 56 is static, i.e., immobile, in particular, fixed. The burner frame 56 can also be made mobile, in particular along the longitudinal axis 37. For this purpose, the burner frame 56 may have rollers on its underside, which may run, in particular, on suitable rails. An axial drive, in particular a pneumatic drive, is advantageous for repositioning. Petition 870250086011, dated 09 / 23 / 2025, p. 25 / 118 18 / 23 of burner 12.

[0070] Along the longitudinal axis 37 or the axis of rotation 29, the flame of the burner 13 has a length Lf and a diameter Df, oriented vertically in relation to it.

[0071] The rotary tubular furnace 9 has an internal diameter Di. Fire protection devices 57, fixed to the inner wall of the rotary tubular furnace 9, are present in the combustion zone 30. Due to the fire protection devices 57, there is a reduced internal diameter Dred in the combustion zone 30. The fire protection devices 47 extend in the axial direction, along a length La, which corresponds to the length of the combustion zone 30. It is important that the length La of the combustion zone 30 is greater than the length Lf of the burner flame 13, and that the burner 12 is arranged in such a way in the rotary tubular furnace 9 that the burner flame 13 is completely within the combustion zone 30, in particular in the axial direction with respect to the axis of rotation 29. It is also important that the diameter Df of the burner flame 13 is smaller than the reduced diameter Dred.Direct contact between the flame and the fire protection equipment is avoided 57.

[0072] In the heat transfer region 31, throwing plates 58 are arranged and, in particular, attached to the interior of the rotary tubular furnace 9. The throwing plates 58 are designed to be open and serve to produce a veil of material 59. It is particularly advantageous that the veil of material 59 be as dense as possible. It is possible to indirectly quantify the density of the veil of material 59, in particular by measuring the temperature of the exhaust gases. The lower the temperature of the exhaust gases, the greater the heat transfer to the material previously achieved. This means that the denser the veil of material 59, the lower the temperature of the exhaust gases and vice versa. The temperature of the exhaust gases results from the burner power, the pre-dose power, i.e., the mass flow rate of the material supplied to the rotary tubular furnace 9, as well as the temperature of the material. The temperature of the Petition 870250086011, dated 09 / 23 / 2025, page 26 / 118 19 / 23 material serves, in particular, as an input variable for regulating burner power. It has been found to be advantageous if the exhaust gas temperature in the exemplary embodiment shown is at least 100 °C.

[0073] Naturally, depending on the material used, the burner 12 used or the fuel gases used, the exhaust gas temperature for monitoring the material veil 59 may assume other values.

[0074] The nozzle arrangement 47 is explained in more detail below, using Figures 3 to 5.

[0075] The nozzle arrangement 47 serves to inject gases into the burner 12, in particular into the burner head 52. According to the exemplary embodiment 16 shown, the nozzle arrangement 47 has several pairs of nozzles, which are arranged in an annular arrangement, in particular concentrically on the longitudinal axis 37 of the burner compartment 38. This annular arrangement has a median axis of arrangement 60 that coincides with the longitudinal axis 37. In the circumferential direction around the median axis of arrangement 60, the pairs of nozzles are spaced apart and, in particular, uniformly spaced from each other. Naturally, more or less than 16 pairs of nozzles may be present. In particular, the circumferential distances from each other may be selected differently and, in particular, as desired.

[0076] Each pair of nozzles includes a fuel gas nozzle 43 for injecting fuel gas into a combustion chamber 61 of the burner 12. Combustion chamber 61 is understood to be the region of the burner 12 surrounded by the burner head 52, which is facing the burner opening 12. The fuel gas nozzle is connected to the fuel gas distribution chamber 17, therefore it is in fluid connection with the fuel gas distribution chamber 17. The fuel gas distribution chamber 17 is designed in an annular shape relative to the longitudinal axis 37 of the burner compartment 38. The fuel gas nozzle 43 has a longitudinal axis of the fuel gas nozzle 62, which is arranged with an angle of inclination n relative to the longitudinal axis 37. In particular, the nozzle pairs Petition 870250086011, dated 09 / 23 / 2025, page 27 / 118 20 / 23 are arranged in relation to the middle axis of arrangement 60 with the respective angle of inclination n in such a way that they intersect the longitudinal axes of the fuel gas nozzles 62. In particular, all the longitudinal axes of the fuel gas nozzles 62 are intersected at a common point P, which is specifically located on the middle axis of arrangement 60.

[0077] The fuel gas nozzle 43 is, in particular, an internal nozzle. The fuel gas nozzle 43 is arranged along the longitudinal axis of fuel gas nozzles 62, at least in sections, inside the secondary gas nozzle 46.

[0078] Each pair of nozzles also includes a secondary gas nozzle 46 for injecting secondary gas into the combustion chamber 61. The secondary gas nozzle 46 is designed to be substantially cylindrical and hollow and, in particular, arranged concentrically to the longitudinal axis of the fuel gas nozzle 62. In particular, the secondary gas nozzle 46 is designed as a single piece and, in particular, as a cylinder sleeve.

[0079] The secondary gas nozzle 46 is connected to the secondary gas distribution chamber 45. The secondary gas distribution chamber 45 extends in an annular shape relative to the longitudinal axis 37 of the burner compartment 38. It is important that the secondary gas distribution chamber 45 be designed separately from the fuel gas distribution chamber 17.

[0080] In the circumferential direction of the longitudinal axis of the fuel gas nozzle 62, the secondary gas nozzle 46 completely surrounds the fuel gas nozzle 43. The secondary gas nozzle 46 forms an outer nozzle that is arranged like a sleeve around the fuel gas nozzle 43. The secondary gas nozzle 46 is arranged at an axial distance from the longitudinal axis of the fuel gas nozzle 62 by a side wall 63 of the fuel gas distribution chamber 17. This spaced arrangement provides a single-flow gap between the side wall 63 and the front opening 64, facing the secondary gas distribution chamber 45 of the fuel nozzle. Petition 870250086011, dated 09 / 23 / 2025, page 28 / 118 21 / 23 secondary 46.

[0081] The fuel gas nozzle 43 has a fuel gas outlet opening 65, which is located in the secondary gas nozzle 46. In this way, a pre-mixing of the fuel gas with the secondary gas can occur in the secondary gas nozzle 46.

[0082] In particular, the fuel gas outlet opening 65 is arranged, with an opening distance A, oriented along the longitudinal axis of the fuel gas nozzles 62 in relation to a secondary gas outlet opening 66 of the secondary gas nozzle 46. The opening distance A is at least 10% in relation to a length Ls of the secondary gas nozzle 46.

[0083] The fuel gas nozzle 43 has a narrowing section 67 and a subsequent contact section 68 along the longitudinal axis of the fuel gas nozzle 62. The narrowing section 67 faces the fuel gas distribution chamber 17. In particular, the fuel gas nozzle 43 is designed as a single piece.

[0084] The cross-sectional surface of the fuel gas nozzle 43 is reduced in the narrowing section, along the longitudinal axis of the fuel gas nozzle 62. The reduction of the cross-sectional surface is particularly regressive, but can also be linear. The outer contour of the narrowing section 47 is designed to be concave or conical, correspondingly. The cross-sectional shape perpendicular to the longitudinal axis of the fuel gas nozzle 62 is particularly round, but can also have other shapes, in particular oval or polygonal.

[0085] The constant section is designed to be particularly cylindrical. It is important that the transition from the narrowing section to the constant section be carried out continuously and, in particular, without edges.

[0086] The fuel gas nozzle 43 is made in a funnel shape or in a trumpet head shape.

[0087] The minimum cross-sectional area of ​​the narrowing section 67 is at most 50% of the maximum cross-sectional area of ​​the section. Petition 870250086011, dated 09 / 23 / 2025, page 29 / 118 22 / 23 narrowing 67.

[0088] Next, the operation of installation 1, in particular the function of burner 12 with nozzle arrangement 47, is explained in more detail.

[0089] In the first device 2, the material is supplied by the material inlet 10 of the rotary tubular furnace 9 and transported through the rotary tubular furnace 9 along the material transport direction 20. In the heat transfer area 21, a thicker, continuous and homogeneous material veil 59 is generated with the throwing plates 58, so that the material is arranged inside the rotary tubular furnace 9 with a very large surface area. The material is heated by means of flame convection from the burner 13, whereby the flame of the burner 13 is directly placed in the rotary tubular furnace 9.

[0090] The flame of burner 13 is generated by burner 12, which is operated with hydrogen as fuel gas. The addition of secondary gas, in particular exhaust gases and / or recirculated inert gas, can retard the combustion of hydrogen gas. This reduces the displacement of fuel gas by volume. High-temperature zones are avoided. In particular, it is ensured that high-temperature zones are arranged exclusively within the combustion zone 30.

[0091] An advantageous injection of fuel gas, on the one hand, and secondary gases, on the other hand, occurs through the nozzle arrangement 47 shown in Figures 3 to 5. The fuel gas, in particular hydrogen, is supplied to burner 12 by the fuel gas distribution chamber 17 and injected by the fuel gas nozzles 43.Due to the special embodiment of the fuel gas nozzle 43, in particular with the narrowing section 67, the fuel gas is advantageously drawn in and released through the outlet opening of the fuel gas nozzle 65 with a comparatively high injection speed. The fuel gas is delivered by the secondary gas nozzle 46, which draws secondary gas from the secondary gas distribution chamber 45 through the front opening 64. The suction speed of the secondary gas is lower than the injection speed of the fuel gas. This difference in gas speed... Petition 870250086011, dated 09 / 23 / 2025, page 30 / 118 23 / 23 fuel for secondary gas results in an improved mixture of fuel gas with secondary gas. The mixing is carried out, in particular, inside the secondary gas nozzle 46. The secondary gas nozzle 46 forms a mixing chamber for mixing fuel gas and secondary gas. It is also advantageous that the fuel gas is injected centrally, i.e., concentrically into the secondary gas nozzle 46.

[0092] The addition of secondary gas, in particular purified exhaust gases and / or inert gas, reduces high temperature zones and therefore the formation of nitrogen oxide.

[0093] In particular, the nozzle arrangement according to the invention ensures an advantageous mixture of fuel gas and secondary gas, in particular before the fuel gas comes into contact with the combustion air in the combustion chamber 61. The fluid streams are shown schematically in Figure 5. Stream arrows 69 indicate fuel gas, stream arrows 70 indicate secondary gas, stream arrows 71 indicate primary air, and stream arrows 72 indicate secondary air. Petition 870250086011, dated 09 / 23 / 2025, p. 31 / 118

Claims

1 / 2 CLAIMS 1. Burner device for an installation (1) for the production of asphalt, characterized in that the burner device comprises a. a rotary tubular furnace (9) that can be driven by rotation around a rotation axis (29) for drying material, b. a burner (12) coupled to the rotary tubular furnace (9) to provide heat in the rotary tubular furnace (9), wherein the burner (12) comprises i. a suction chamber (39) for sucking air, ii. a fuel gas line (14) connected to the burner (12) to supply fuel gas, iii. at least one secondary gas line (24, 35) connected to the burner (12) to supply secondary gas.

2. Burner device, according to claim 1, characterized in that at least one secondary gas line has an exhaust gas recirculation line (24) to recirculate exhaust gases from the burner device into the burner (12).

3. Burner device, according to claim 2, characterized in that the exhaust gas recirculation line (24) is fluidically connected to the rotary tubular furnace (9) and / or to at least one additional exhaust gas source (9, 26) of the burner device.

4. Burner device, according to claim 2 or 3, characterized in that the exhaust gas recirculation line (24) is connected to an exhaust gas purification unit (5, 6, 7, 8).

5. Burner device, according to any of the preceding claims, characterized in that at least one secondary gas line has an inert gas recirculation line (35) to supply inert gas to the burner (12).

6. Burner device, according to any of the preceding claims, characterized in that it has a mixing chamber (36, 46) Petition 870250086011, dated 23 / 09 / 2025, p. 32 / 118 2 / 2 for mixing fuel gas and secondary gas.

7. Burner device according to claim 6, characterized in that the fuel gas line (14) and the secondary gas line (24, 35) are connected to the mixing chamber (36, 46).

8. Burner device, according to claim 6 or 7, characterized in that an air line (19) is connected to the burner (12), wherein the air line (19) is connected, in particular, directly to the burner (12) and, in particular, is guided through the mixing chamber (36, 46).

9. An installation characterized by the fact that it is intended for the production of asphalt in a burner device, as defined in any of the preceding claims.

10. Method for supplying heat into a rotary tubular kiln (9) of a burner device in an asphalt plant (1) characterized in that it has the methodological steps - supplying fuel gas into a burner (12) by means of a fuel gas line (14), supplying secondary gas to the burner (12) by means of a secondary gas line (24, 35), - supplying air into the burner (12), - burning the fuel gas and air in the burner (12) in the presence of the secondary gas. Petition 870250086011, dated 23 / 09 / 2025, page 33 / 118

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