Method of combusting hydrogen in industrial furnace using multiple nozzle burner, particularly in glass furnace or metal melting furnace, and burner

Abstract

To provide a method of combusting hydrogen gas in an industrial furnace.SOLUTION: The method of combusting hydrogen gas in an industrial furnace using a multiple nozzle burner accompanying a controllable flow of a hydrogen fuel composition and an additional gas composition flowing through a cavity to the industrial furnace, whereby the hydrogen fuel composition is introduced into the cavity from a multiple nozzle burner by a center flow of gas from at least one center gas nozzle, accompanying a concurrent feed of at least a further independent flow of an additional gas composition coming from at least one coaxial nozzle, with the center flow of the gas of the hydrogen fuel gas composition being surrounded by a coaxial flow of the gas of the additional gas composition, is characterized in that the gas momentum per one second of the center flow of the hydrogen fuel gas composition at the outlet of the center gas nozzle is in a range of 0.001 to 1.2 [kg H2 m / s2], and the gas momentum per one second of the coaxial flow of the additional gas composition at the outlet of the coaxial nozzle is in a range of 0.01 to 10.4 [kg O2 m / s2], and the ratio of the heating burner output (WCHEM [W]) relative to the kinetic force (WKIN [W]) of the hydrogen fuel gas composition, i.e., WRATIO is in a range of 100.000 to 4000.000 [1].SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for burning hydrogen gas in an industrial furnace by means of a multi-nozzle burner with a controllable flow of a hydrogen fuel gas composition and an additional gas composition through a cavity into the industrial furnace to form a reaction mixture of the hydrogen fuel gas composition and an additional gas composition for burning in the industrial furnace, in particular a glass furnace or a metal melting furnace, according to the preamble of claim 1.

[0002] Furthermore, the present invention relates to a multi-nozzle burner for implementing a method for burning hydrogen in an industrial furnace, i.e. a multi-nozzle burner for burning hydrogen gas in an industrial furnace, in particular a glass furnace or a metal melting furnace, the structure of the multi-nozzle burner being adapted for a controllable flow of the hydrogen fuel gas composition and an additional gas composition through a cavity into the industrial furnace to form a reaction mixture of the hydrogen fuel gas composition and the additional gas composition for combustion in the industrial furnace.

[0003] Industrial production techniques, e.g. glass melting, metal melting or ceramic material heating, require very high operating temperatures necessary for the thermal treatment of products. Traditionally, such high temperatures (600 °C to 1700 °C) are achieved by chemical reactions between a fuel and an oxidizer. The most common types of fuel are gases, e.g. methane (natural gas), propane, coal gas and / or various liquid fuels, e.g. light and / or heavy oil. The fuel is mixed with an oxidizer, which is typically combustion air or oxygen gas with an O2 concentration of 90 to 99% by weight. The combustion system consists of a burner in the superstructure of the furnace, which generates a flame on the heated material. The working principle of the burner is the simultaneous injection of fuel and oxidizer (combustion air or oxygen) into the furnace interior. Both of these gases react and burn at a temperature higher than the ignition temperature of the fuel gas, thus adding energy to the process.

[0004] In the case of combustion of natural gas and oxygen, the resulting flame and its temperature often reach very high values, close to 2700 °C, considerably higher than the heat resistance of the furnace walls and burner construction materials. This problem is significantly complicated when the fuel gas is hydrogen. Hydrogen in combination with oxygen exhibits very fast reaction rates, which poses a great risk of overheating of the burners and furnace walls.

[0005] The challenges of natural gas and oxy-combustion as in the prior art can be addressed by improved control of the flame as outlined in WO 2007 / 048429. Another solution is described in EP 0687853 and EP 0762050.

[0006] In the applicant's WO 2020 / 078775, a combustion gas injector for firing regeneratively or recuperatively heated industrial furnaces is described that comprises only a gas supply tube and an opening. In this publication, the longitudinal diffuser has a metallic coolable diffuser tube that forms an opening intended to form an end to the combustion gas injector's opening relative to the ceramic injector insert opening, the connection of which is designed with a free jet opening angle. It is proposed that the longitudinal diffuser is designed as a flat longitudinal diffuser. In this publication, the diffuser tube is formed with a diffuser output flat tube and a diffuser input flat tube.

[0007] In the device of US Pat. No. 5,299,929, there are two oxygen streams directed through flat slots above and below a central stream of gas containing the target to form two combustion zones.

[0008] In the design described in US Pat. No. 6,190,158, the burner is configured with a central flow of oxygen that is concentrically surrounded by gas, which is in turn surrounded by oxygen.

[0009] The applicant's WO 2015 / 007743, mentioned at the outset, describes a method for burning gases in industrial furnaces, in particular glass furnaces or metal melting furnaces, with the aid of a multi-nozzle burner with a controllable flow of fuel gas and additional gas nozzles, where the essence of the invention is that the fuel gas is injected into the cavity of the burner by at least one central gas nozzle, with the simultaneous introduction of two independent flows of additional gas, such that the fuel gas is surrounded by a concentric flow of primary additional gas, which is also surrounded by a concentric flow of secondary additional gas.

[0010] However, the above solutions cannot be applied to the hydrogen combustion problem itself. In the case of hydrogen gas and oxygen combustion, the problem of flame stability obtained must be solved in a new approach, and it has been found that the flame temperature during hydrogen gas and oxygen combustion reaches very high values. For this reason, the hydrogen combustion problem is even more important than the combustion using combusted natural gas.

[0011] Although hydrogen combustion itself is of high strategic interest and requisite specific solutions to the problems mentioned above have been proposed in recent years, hydrogen combustion itself remains an ongoing research and development issue.

[0012] EP 3450843 A1 describes an all-metal burner in which the outer burner tube extends axially of the inner tube, meaning that the tube tips of the nozzle structure are not in the same plane to allow for hydrogen combustion.

[0013] JP 2019-44977 A describes a nozzle structure with a constriction mechanism to make the flow path of the peripheral oxygen flow narrower; essentially, the gas flow is throttled by the constriction mechanism.

[0014] JP 2019-39590 A proposes a nozzle structure in which the inner hydrogen gas tube is spaced apart, the primary air tube covers the hydrogen gas tube, and the secondary peripheral air tube covers the primary air tube, in order to inhibit mixing of the hydrogen gas and air, so that the hydrogen tube and the combustion air tube are not in one plane.

[0015] WO 2019 / 039608 proposes a three-tube configuration and generally describes a multi-tube structure with a protruding inner central gas tube which is an oxygen flow tube, and an outermost hydrogen gas tube covering all of the inner oxygen tubes. It is essential that the hydrogen gas flow is at the periphery, not in the center.

[0016] US 2018 / 0156451 describes an ignition device in combination with a hydrogen gas tube that is remotely located relative to the oxygen tube.

[0017] All the above solutions for hydrogen combustion are either related to burner designs including ignition devices or require nozzle configurations with different protrusions of the hydrogen or oxygen tubes / nozzles. Furthermore, all the proposed solutions are not suitable for furnaces with high operating temperatures, e.g. glass furnaces, where temperatures typically reach the range of 1400°C to 1650°C.

[0018] The object of the present invention is to further address or solve at least some of the problems mentioned above. In particular, the design of a new combustion method and a new burner are specifically adapted to the requirements and margins of hydrogen combustion, i.e. the use of additional gases based on oxygen, allowing for precise setting of the hydrogen combustion process. Thereby, it is very useful to improve the hydrogen combustion process also with careful attention to NOx emissions and to improve high radiation efficiency. In particular, flame control, mainly preventing overheating of the furnace and burner structure, is a further problem to be solved by the hydrogen combustion method and hydrogen combustion burner proposed in the present invention, a problem that should not be underestimated.

[0019] SUMMARY OF THE PRESENT EMBODIMENT It is therefore a primary object of the present invention to introduce an improved hydrogen combustion method and an improved design of a hydrogen combustion burner for implementing the improved hydrogen combustion method.

[0020] This problem is solved by the method according to claim 1.

[0021] The invention therefore takes as its starting point the method described at the beginning, which is a method for burning hydrogen gas in an industrial furnace by means of a multi-nozzle burner with a controllable flow of the hydrogen fuel gas composition and an additional gas composition through a cavity into the industrial furnace to form a reaction mixture of the hydrogen fuel gas composition and an additional gas composition for combustion in the industrial furnace, in particular a glass furnace or a metal melting furnace.

[0022] Thus, the present invention starts from the consideration that the use of a multi-nozzle burner is well suited to provide a simultaneous controllable flow of a hydrogen fuel gas composition and an additional gas composition through a cavity into an industrial furnace to form a reaction mixture of the compositions. Advantageously, especially for industrial furnaces operating at high temperatures, the reaction mixture of the hydrogen fuel gas and the additional gas composition is instantly ignited when simultaneously injected from the multi-nozzle burner.

[0023] According to the present invention, in this method, - introducing the hydrogen fuel gas composition into the cavity from a multi-nozzle burner by a central flow of gas from at least one central gas nozzle with simultaneous introduction of at least one independent additional flow of an additional gas composition from at least one concentric gas nozzle; - a central flow of gas of the hydrogen fuel gas composition is surrounded by a concentric flow of gas of at least a primary additional gas composition.

[0024] Here, the present invention has recognized that a central flow of gas should be established from the central flow of gas of the hydrogen fuel gas composition, where the present invention has recognized that hydrogen is a relatively light gas and therefore should be in the center of the flame and should be ignited in the center of the flame.

[0025] According to the present invention, the gas stream of hydrogen fuel gas is provided as a central flow of gas. Thus, in contrast to the prior art concepts, the gas stream of hydrogen fuel gas is not provided to the periphery. In the present case, the central flow of gas of the hydrogen fuel gas composition is surrounded by a concentric flow of gas of at least a primary additional gas composition.

[0026] Other concepts provide a primary additional gas composition in the central stream, but these prior art concepts prioritize providing a stable inner portion of the flame established by the relatively heavy additional gas.

[0027] On the other hand, the present invention recognizes that an advantageous solution is provided by establishing a central flow of relatively light hydrogen fuel gas, which should be stabilized at the periphery by a flow of relatively heavy additional gas composition. Thus, in effect, the concept of the present invention establishes a kind of envelopment of the central flow of relatively light hydrogen fuel gas with the surrounding and / or peripheral relatively heavy primary additional gas composition. It has been found that this configuration of multi-nozzle flows of gas composition is more suitable for providing stabilized autoignition of flames in high temperature surroundings (which does not require an igniter) and also providing a stable flame when injected into industrial furnaces. This central flow of gas of hydrogen fuel gas composition surrounded by a concentric flow of gas of primary additional gas composition has been found to be superior compared to the prior art concepts proposing a conceptually different arrangement of gas flows.

[0028] According to the present invention, It has further been appreciated that the hydrogen fuel gas composition is formed by a first fuel gas component of 80% by weight or more of hydrogen gas and 20% by weight or less of another fuel gas or gas component other than hydrogen gas.

[0029] It is therefore to be understood that the hydrogen fuel gas composition may contain up to 20% by weight of any type of gas, e.g., other fuel gases other than hydrogen gas, non-fuel gases, or any type of other gases may be present. The other fuel gases may be provided by hydrocarbon gases or biogas, etc., and the non-fuel gas may be, for example, steam or any type of other gas. It is to be understood that the hydrogen fuel gas composition comprises a majority of hydrogen gas, which may be 80% by weight or more. Thus, essentially, in a preferred, non-limiting embodiment, rather pure hydrogen gas is set to constitute the hydrogen fuel gas composition.

[0030] For example, the hydrogen fuel gas composition may consist entirely of more or less pure hydrogen gas, that is, 99% or 100% by weight hydrogen gas, excluding unavoidable minor impurities. Nevertheless, any suitable blend of fuel gases of any type is also possible in the hydrogen fuel gas composition, so long as hydrogen gas constitutes 80% or more by weight of the components. For example, hydrogen gas may form at least 80% by weight, e.g., 85%, 90% or 95% by weight, etc., of the first fuel gas component, with the remainder of the hydrogen fuel gas composition being formed by one or more other fuel gas components or some other gas.

[0031] It has further been realised that in accordance with the present invention, the additional gas composition is formed by an oxygen-containing first oxidant gas component having an oxygen content of greater than 80% by weight.

[0032] Thus, according to the concept of the present invention, in principle, the additional gas composition can be provided as any type of oxidizer gas containing more than 80% by weight of oxygen to form the first oxidizer gas component. Other gases or oxidizer gas components may be present. Another oxidizer gas component, preferably oxygen, can be present in an amount of 20% by weight or less. This means that the additional gas composition can be formed in the second oxidizer gas component as air or from air and oxygen or air enriched with oxygen.

[0033] Thus, the oxygen content of the additional gas composition includes oxygen of another oxidizer having an oxygen content of 80% or more by weight, such that the additional gas composition is made up of more than 80% by weight of oxygen.

[0034] Thus, the additional gas composition is formed by a first oxidizer gas component of oxygen, but according to the invention the oxygen content is greater than 80% by weight or another oxidizer having an oxygen content greater than 80% by weight, meaning that the first oxidizer gas component provides the additional gas composition with at least 80% by weight or more of oxygen.

[0035] Preferably, there may be another oxidizer gas component other than oxygen, such as any kind of oxygen-containing mixture or gas, such as air or oxygen-rich air, with a concentration of up to 20% by weight. Thus, the additional gas composition may not only contain another oxidizer gas component other than oxygen, such as air or another oxidizing gas, with a concentration of up to 20% by weight, but may also contain any other gas. This means that the other oxidizer gas component other than oxygen does not necessarily have to be an oxidizing gas, but may also contain an inert gas or other gas, such as air or a constituent gas of air, such as nitrogen, CO2, argon, etc. However, it should be understood that in certain preferred embodiments, the hydrogen fuel gas composition and the additional gas composition are provided from the process of electrolysis of water. This means that by passing an electric current through water, the water is decomposed into oxygen gas and hydrogen gas. This technology can be used to produce hydrogen gas as the main component of hydrogen fuel and breathable oxygen gas, or the two can be mixed into oxyhydrogen, which is more volatile but can also be used as a fuel.

[0036] Thus, briefly, in a particularly preferred embodiment, the hydrogen fuel gas composition is formed by hydrogen gas containing unavoidable impurities and the additional gas composition is formed by oxygen gas containing unavoidable impurities, in particular hydrogen gas and oxygen gas derived from a water electrolysis process.

[0037] Further, according to the present invention, a1) The gas momentum per second of the central flow of the hydrogen fuel gas composition at the outlet of the central gas nozzle is 0.001 to 1.2 [kgH2m / s 2 ] range, b1) The gas momentum per second of the concentric flow of the primary additional gas composition at the outlet of the concentric gas nozzle is 0.01 to 10.4 [kgO2 m / s 2 ] range It is provided that:

[0038] Here, the invention immediately takes into account the light weight properties of the hydrogen fuel gas composition. From this consideration, it follows that the flame stabilization parameters should be defined in terms of momentum velocity. This is a momentum value per second for each gas flow. For this reason, the hydrogen fuel gas flow and the additional gas flow are defined here by the momentum per second for each gas flow, as specified in the independent claims. The momentum velocity margin takes into account an advantageous intermediate velocity range for each gas flow.

[0039] The light weight properties of the hydrogen fuel gas composition are taken into account with momentum velocity values ​​that are approximately one order of magnitude smaller than each of the momentum velocity values ​​of the additional gas compositions, as seen from the defined values ​​of momentum per second. These features, in combination with the central gas flow of the hydrogen fuel gas surrounded by a concentric gas flow of the additional gas, ensure stable flame formation when the reactive mixture of the hydrogen fuel gas composition and the additional gas composition is ignited for combustion in an industrial furnace.

[0040] Furthermore, for the above mentioned features (a1) and (b1) as defined in the method of the present invention, some intermediate velocity states of flow are defined, taking into account the significant weight difference between the hydrogen fuel gas and the oxidizer additional gas. The advantage of the intermediate velocity range (which is the range between the low velocity state and the high velocity state) is that it provides a good and efficient combustion process while the emissions are kept low.

[0041] Furthermore, flame control and energy delivery to industrial furnaces is favorably supported in moderate velocity flame conditions due to propensity, providing advantages over other concepts.

[0042] Nevertheless, on the one hand, taking into account the above parameters, not only should optimal combustion be observed, but on the other hand, the temperature range should also be within the acceptable temperature range, so that overheating of the refractory, walls, burners and other structures of the furnace should be prevented.

[0043] Thus, the present invention provides c) It is further proceeded by the finding that the ratio of the heating burner power (WCHEM [W]) to the kinetic power of the hydrogen fuel gas composition (WKIN [W]) is in the range WRATIO = 100.000 to 4.000.000 [1].

[0044] Considering this range of heating burner power versus hydrogen fuel gas composition momentum, it is ensured that while the momentum is greater, at intermediate to high speed conditions of flame momentum, more precisely at intermediate to high momentum conditions of gas flow for control of flame momentum, the heating burner power is still kept low enough to prevent overheating of the furnace refractories, whereas at intermediate to low momentum of hydrogen fuel gas composition with rather low momentum, the intake of heating burner power is further limited to prevent overheating of the industrial furnace refractories.

[0045] Thus, the above mentioned ratio of heating burner power to hydrogen fuel gas composition motive power is to balance the optimum weighting between chemical energy capture per gas composition motive power while providing optimum combustion, however, on the other hand, this ratio is set with a margin just below and above the mid-speed range to prevent overheating of the industrial furnace refractories.

[0046] Thus, likewise, the object with respect to hydrogen-fired burners is achieved according to the invention with a multi-nozzle burner according to claim 22 of the invention.

[0047] Thus, in this aspect, the invention begins with a multi-nozzle burner for burning hydrogen gas in an industrial furnace, in particular a glass furnace or a metal melting furnace, the multi-nozzle burner being adapted for a controllable flow of a hydrogen fuel gas composition and an additional gas composition through a cavity into the industrial furnace to form a reaction mixture of the hydrogen fuel gas composition and an additional gas composition for burning in the industrial furnace.

[0048] Starting from these considerations, the concept of the present invention is to provide a multi-nozzle burner having: - the hydrogen fuel gas composition is introduced into the cavity from the multi-nozzle burner by a central flow of gas from at least one central gas nozzle of the multi-nozzle burner with simultaneous introduction of at least one independent additional flow of an additional gas composition from at least one concentric gas nozzle of the multi-nozzle burner; - a central flow of gas of the hydrogen fuel gas composition is surrounded by a concentric flow of gas of at least a primary additional gas composition, in particular the concentric flow of gas of the primary additional gas composition is a peripheral concentric flow of gas, and the multi-nozzle burner is further adapted to carry out the claimed inventive method.

[0049] Preferably, the multi-nozzle burner comprises an injection tube body with a central tube having a central opening and peripheral concentric tubes with peripheral openings, the injection tube body being fixed with an outlet to the ceramic component, the peripheral concentric tubes and the central tube comprising at least one central gas nozzle and at least one concentric gas nozzle, in particular the central gas nozzle being surrounded by the concentric gas nozzle on an outer periphery forming the outer body of the injection tube body, optionally the concentric gas nozzle surrounding a further concentric gas nozzle on an outer periphery forming the outer body of the injection tube body.

[0050] In particular, the tips of the central gas nozzle, the concentric gas nozzle and, optionally, the further concentric gas nozzle are positioned at the same distance within the cavity.

[0051] These and further developed configurations of the invention are further outlined in the dependent claims, whereby the mentioned advantages of the proposed concept are further improved. For each feature of the dependent claims, independent protection is claimed, independent of all other features of the present disclosure.

[0052] In a first particularly preferred development, the hydrogen fuel gas composition is introduced into the cavity of the multi-nozzle burner from at least one central gas nozzle with simultaneous injection of only the first independent further flow of the additional gas composition, i.e. the primary additional gas composition mentioned above. This means that the central flow of gas of the hydrogen fuel gas composition is surrounded by a concentric flow of gas of the primary additional gas composition. Respectively, in this first preferred development, it has already been found that a two-nozzle burner having a central gas nozzle for providing the hydrogen fuel gas composition and a single concentric gas nozzle for providing the additional gas composition in a concentric flow is particularly sufficient and useful for realizing the inventive concept. This development of the inventive concept is based on a two-nozzle burner having one single central gas nozzle and one single concentric gas nozzle.

[0053] In a second further development, the multi-nozzle burner can be provided with first and second concentric gas nozzles around the central gas nozzle to form a three-nozzle burner, which is based on an even more advantageous and more advanced structure of the three-nozzle burner.

[0054] According to this second development, the three-nozzle burner can be operated in a first preferred concept and in an even more preferred second concept, as outlined below.

[0055] According to a first conceptual operation of the second development of the three-nozzle burner, a second gas flow of hydrogen fuel gas and a concentric flow of a primary additional gas and further a concentric flow of a secondary additional gas are provided, the latter being provided through a first concentric gas nozzle and a second concentric gas nozzle, while a central gas nozzle is for providing a central flow of the hydrogen fuel gas composition.

[0056] In a second particularly preferred development of the first concept, it is preferable to introduce the hydrogen fuel gas composition into the cavity of the multi-nozzle burner from at least one central gas nozzle with simultaneous injection of at least first and second independent further flows of an additional gas composition, - a central flow of gas of the hydrogen fuel gas composition is surrounded by a concentric flow of gas of the primary additional gas composition; - a concentric flow of gas of the primary additional gas composition surrounds a concentric flow of gas of the secondary additional gas composition, said concentric flow being between a central flow of gas of the hydrogen fuel gas composition and the concentric flow of gas of the primary additional gas composition.

[0057] Preferably, in the second development of the first concept, (b2) the gas momentum per second of the concentric flow of the secondary additional gas composition at the outlet of the concentric gas nozzle is between 0.01 and 10.4 [kgO2 m / s 2 It is provided that the range is .

[0058] A development of the second concept is particularly useful for increasing the oxygen flow rate through increased volume, which may be beneficial depending on the combustion parameters of the fuel gas.

[0059] In a second concept of the second development, the amount of fuel gas is increased by providing a hydrogen fuel gas composition through a central gas nozzle and further through a first concentric gas nozzle surrounding the central gas nozzle, while a single concentric flow of a primary additional gas composition is provided through the peripheral concentric gas nozzles as follows:

[0060] The following non-limiting developments may be useful in explaining the feature of the invention in which a central flow of gas of a hydrogen fuel gas composition is surrounded by a concentric flow of gas of at least a primary additional gas composition.

[0061] Preferably, the primary concentric flow of additional gas composition is a peripheral concentric flow of gas. For this reason, in the first development shown above, the hydrogen fuel gas composition is introduced into the cavity from a multi-nozzle burner by a central flow of hydrogen gas from at least one central gas nozzle and possibly one or more further concentric flows of hydrogen gas from at least one concentric gas nozzle. For this reason, one or more concentric flows of hydrogen gas from at least one concentric gas nozzle cannot be provided in direct contact with the central flow of hydrogen gas with the simultaneous introduction of at least one independent further peripheral flow of additional gas composition from one single concentric peripheral gas nozzle.

[0062] Preferably, in a particularly preferred, non-limiting example of this first embodiment, only a single central flow of hydrogen gas from a central gas nozzle is co-injected with a peripheral flow of additional gas composition from a single concentric peripheral gas nozzle.

[0063] Preferably, in a particularly preferred, non-limiting example of the second embodiment set forth above for the second concept, a central flow of hydrogen gas from a central gas nozzle and a concentric flow of hydrogen gas from directly contacting concentric gas nozzles are co-injected with a peripheral flow of an additional gas composition from one single concentric peripheral gas nozzle.

[0064] By peripheral flow and peripheral nozzle is meant a flow at the periphery of the gas flow and the respective nozzle, that is to say a peripheral tube of the outer part of the burner. By using this peripheral tube of the outer part of the burner for the primary additional gas composition according to the concept of the present invention, said kind of envelopment of the central flow of the relatively light hydrogen fuel gas by the surrounding and peripheral relatively heavy primary additional gas composition is established.

[0065] In a further non-limiting example of another embodiment of the first concept as shown above, an additional flow of a secondary relatively heavy additional gas composition at the inner circumference can be provided in direct contact with the peripheral flow of the primary relatively heavy additional gas composition. Although of little importance, this type of embodiment is still useful and helpful when increasing the flow rate of additional gas, in particular oxygen, in terms of improving the combustion process under some circumstances. This may be the case where the oxygen content of the first oxidant gas component is to be considered insufficient to combust the hydrogen fuel gas composition of a particular configuration.

[0066] The gas momentum velocity of the stream is set in a range that takes into account the light weight characteristics of the hydrogen fuel gas composition and the relatively large weight of the additional gas that is used.

[0067] In a second particularly preferred development of the second concept, the hydrogen fuel gas composition is preferably introduced into the cavity of the multi-nozzle burner: a central flow of gas of the hydrogen fuel gas composition from at least one central gas nozzle and a concentric flow of gas of the hydrogen fuel gas composition from at least one further concentric gas nozzle; introducing at least one additional gas composition from at least one concentric gas nozzle with simultaneous injection of at least one separate further flow of the at least one additional gas composition; - a central flow of gas of the hydrogen fuel gas composition is surrounded by concentric flows of gas of the hydrogen fuel gas composition; - The concentric flow of gas of the hydrogen fuel gas composition is surrounded by a concentric flow of the primary and / or secondary additional gas composition.

[0068] In particular therein, the concentric flow of the primary or secondary additional gas composition is the peripheral concentric flow of gas. For this reason, in this preferred embodiment, from the center to the periphery of the multi-nozzle burner, in particular the three or four nozzle burner, the order of "central hydrogen fuel gas - concentric hydrogen fuel gas - concentric primary additional gas - and / or - concentric secondary additional gas" is maintained.

[0069] Preferably, in a second development of the second concept, (a2) the gas momentum per second of the concentric flow of the hydrogen fuel gas composition at the outlet of the concentric gas nozzle is 0.001 to 1.2 [kgH2m / s 2 It is provided that the range is .

[0070] Preferably, the reaction mixture of the hydrogen fuel gas composition and the additional gas composition is led into the furnace through a cavity provided in the ceramic part, in particular through a cavity provided in the ceramic wall of the furnace, thereby achieving a modern and flexible installation of the burners in the furnace.

[0071] In a particularly preferred development, the reaction mixture of the hydrogen fuel gas composition and the additional gas composition is led into the furnace through a cavity, the ratio between the outer periphery of the burner cross-section and the periphery of the cavity cross-section being in the range of 0.95 to 1.0 or 1.0 to 1.05.

[0072] That is to say, in a first preferred variant, the burner cross section is slightly smaller than the cavity cross section. This has some main advantages, since in most cases the burner can be inserted into the cavity, thus allowing a gradual adaptation of the effective cavity length. An example is shown in FIG. 3. In a second preferred variant, the burner cross section is slightly larger than the cavity cross section. This has the advantage that a particularly favorable isolated and gas-tight mounting of the burner in the cavity is possible.

[0073] The shape of the cavity can be of various types to aid in flame formation, but the margins and ratio of cross section to length of the cavity have been found to be important in optimizing the flame shape while keeping in mind the combustion efficiency and heat release in the flame.

[0074] Preferably, the cavity has a cross-sectional shape in the shape of a circular or elliptical or rectangular flat slot.

[0075] Preferably, in a first variant, the reaction mixture of the hydrogen fuel gas composition and the additional gas composition is guided through a cavity so as to be introduced into the furnace, a) The cavity has a circular cross-sectional shape such that the cavity has the shape of a cylinder with an axial length and a circular bottom region, and the ratio between the diameter of the bottom region and the axial length of the cylinder is in the range of 2 to 6.

[0076] Preferably, in the second variant, the reaction mixture of the hydrogen fuel gas composition and the additional gas composition is guided through a cavity so as to be introduced into the furnace, b) the cavity has an elliptical or rectangular cross-sectional shape such that the cavity has an axial length and an elliptical or rectangular slot shape of an elliptical or rectangular base region, and the ratio between the major axis of the elliptical or rectangular base region and the axial length of the elliptical or rectangular slot is in the range of 1 to 4.

[0077] These ratios defined for the cylinder and the flattened slots have a beneficial flame directing effect and also place the optimum distance of the flame hot zone to the burner body.

[0078] A somewhat broader range of gas flow velocities has dynamics that are favorable for combustion at velocities between 5 and 85 m / s. In particular, low gas flow velocities well below 40 m / s are preferred. This choice is made to keep temperatures within acceptable limits, especially when operating with hydrogen combustion, which tends to produce higher temperatures compared to hydrocarbon fuel combustion. It has been shown that particularly low temperatures are achievable when operating at low velocities, preferably below 40 m / s.

[0079] Moreover, the velocity ranges as described below help stabilize the flame itself, taking into account the lightweight characteristics of the hydrogen fuel gas, which mainly contains hydrogen, compared to the additional gases, which mainly contain oxygen. Therefore, the following ratios are basically determined by the significantly lower weight ratio of hydrogen molecules compared to oxygen molecules. Although the essential trends and ratios described below are obviously different from the usual parameters for describing the characteristics of hydrocarbon combustion, they should be considered in the light of the momentum velocities defined above for the present invention.

[0080] In a particularly preferred development of the first development, the hydrogen fuel gas composition is introduced into the cavity through at least a central gas nozzle, at the outlet of which the central flow of gases of the hydrogen fuel gas composition has a velocity in the range of 5 to 85 m / s, particularly preferably in the range of less than 40 m / s.

[0081] Preferably further, in particular for this preferred development mentioned above, the primary additional gas composition is introduced into the burner in a rate-controllable volume in the range of 90-110% by weight of that required for stoichiometric combustion of the hydrogen fuel gas composition.

[0082] Preferably further, in particular for this preferred development mentioned above, the value of the central flow of gas of the hydrogen fuel gas composition with respect to the velocity of the concentric flow of gas of the primary additional gas composition (VO2) satisfies the following relationship: VH2:vO2=1:(0.3~1.8) is given by:

[0083] For this reason, in a first particularly preferred embodiment, the hydrogen fuel gas is introduced into the ceramic component through a central nozzle at a velocity VH2 in the range of 5-85 m / s, preferably at a velocity VH2 of less than 40 m / s. It is further preferred to introduce a primary additional gas into the burner in a controllable volume in the range of 90-110% by weight of that required for stoichiometric combustion of the fuel gas. Further preferably, the velocity VO2 of the additional gas satisfies the following relationship: VH2:vO2=1:(0.3~1.8) The value is given by:

[0084] Preferably, the additional gas has a value that accommodates the lower velocity of the preferred hydrogen fuel gas composition.

[0085] In a particularly preferred development, the flow cross-sectional area of ​​the hydrogen fuel gas composition is given by the opening area of ​​the central gas nozzle, optionally by the opening area of ​​the central gas nozzle plus the opening areas of the further concentric gas nozzles, - the flow cross-sectional area of ​​the additional gas composition is given by the opening area of ​​at least one concentric gas nozzle, optionally given by the opening area of ​​the at least one concentric gas nozzle plus the opening areas of further concentric gas nozzles for the primary and secondary additional gas compositions; and / or the cross-sectional flow area of ​​the hydrogen fuel gas composition and the cross-sectional flow area of ​​the additional gas composition have the following relationship:

number

[0086] In a particularly preferred development of the second development, the hydrogen fuel gas composition is introduced into the cavity through at least a concentric gas nozzle, at the outlet of which the concentric flow of gases of the hydrogen fuel gas composition has a velocity in the range of 5 to 85 m / s, in particular a velocity of less than 40 m / s.

[0087] Preferably further, in particular for this preferred development mentioned above, a secondary additional gas composition is introduced into the burner in a rate-controllable capacity in the range of 90-110% by weight of that required for stoichiometric combustion of the hydrogen fuel gas composition.

[0088] Preferably further, in particular for this preferred development mentioned above, the value of the concentric flow of gas of the hydrogen fuel gas composition with respect to the velocity of the concentric flow of gas of the primary and / or secondary additional gas composition (vO2) satisfies the following relationship: VH2:vO2=1:(0.3~1.8) is given by:

[0089] For this reason, in a second particularly preferred embodiment, the hydrogen fuel gas is introduced into the ceramic component through a central nozzle 1 at a velocity in the range of 5 to 85 m / s, while the primary and / or secondary additional gas is initially introduced into the burner in a controllable volume in the range of 90 to 110% by weight required for stoichiometric combustion of the fuel gas, the velocity values ​​of which satisfy the following relationship: VH2:vO2=1:(0.3~1.8) is given by:

[0090] In particular, the cross-sectional flow area of ​​the hydrogen fuel gas composition is determined by the opening area of ​​the central gas nozzle (e.g., as shown in FIG. 1 ).

number

number

[0091] The flow cross-sectional area of ​​the hydrogen flow (the area of ​​the central gas nozzle (FIG. 1), optionally the area of ​​the central gas nozzle plus the opening area of ​​the further concentric gas nozzles (FIG. 3)) and the flow cross-sectional area of ​​the additional gas flow, in particular the oxygen flow (the concentric gas nozzle area of ​​the primary and / or secondary additional gas regions in the concentric peripheral gas nozzles) are related by the following relationship:

number

[0092] In a particularly preferred development, - for each multi-nozzle burner, at least one injector is provided which passes through a ceramic component; - by means of said injector, an additional gas flow, preferably an additional gas flow of oxygen or an additional gas flow containing a purge gas containing more than 20% by weight of oxygen, is introduced into the industrial furnace, - Separating the water vapor-rich zone of the hydrogen flame of the reaction mixture from the molten material in the furnace by introducing an additional gas flow.

[0093] Furthermore, in a preferred development, The input hydrogen fuel gas composition and the additional gas composition and the amount and rate of the additional gas flow are controlled, particularly continuously controlled.

[0094] The subject matter of claim 1 and the other independent claims is to be understood as having similar and / or identical preferred embodiments, in particular as further defined in the dependent claims.

[0095] It is to be understood that a preferred embodiment of the invention can also be any combination of the dependent claims or the above embodiments with the respective independent claims.

[0096] These and other aspects of the invention are apparent from and will be elucidated with reference to the embodiments described below. An embodiment of the invention is described below on the basis of the drawings in comparison with the prior art. The prior art is also partially shown. The latter is not necessarily intended to represent the embodiment to scale. The drawings are shown in schematic and / or slightly distorted form if useful for the explanation. For the addition of lessons immediately discernible from the drawings, reference is made to the relevant prior art. It should be noted that numerous modifications and changes can be made to the form and details of the embodiments without departing from the general concept of the invention. The features of the invention disclosed in the description, the drawings and the claims may be essential for further development of the invention, either individually or in any combination.

[0097] In addition, all combinations of at least two of the features disclosed in the description, drawings and / or claims are within the scope of the invention. The general concept of the invention is not limited to the exact forms or details of the preferred embodiments shown and described below, nor is it limited to any purpose more limited than that claimed in the claims. For the specified design ranges, values ​​within the specified boundaries are also disclosed as boundary values ​​and are therefore optionally applicable and claimable.

[0098] Further advantages, features and details of the invention can be obtained from the following description of preferred embodiments as well as the drawings and tables.

[0099] Table I lists the physical variables important to the design and operation of a hydrogen-oxygen burner. [Brief description of the drawings]

[0100] [Figure 1] 1 is a schematic longitudinal cross-sectional view of a hydrogen burner scheme with a two-nozzle design and ceramic components according to a first preferred embodiment. In a first variant, the nozzles are cylindrical or at least rounded. [Diagram 2] 1 shows a schematic longitudinal section of an alternative design of a hydrogen burner scheme with a three-nozzle design and ceramic components according to a second preferred embodiment. In a first variant, the nozzles are cylindrical or at least rounded. [Diagram 3] 1 is a cross-sectional view of a preferred embodiment of a burner according to a first embodiment, which however also relates in principle to the second embodiment of the invention. [Figure 4] FIG. 4 is a three-dimensional view of the preferred embodiment of FIG. [Diagram 5] 1 shows a schematic longitudinal section of a hydrogen burner scheme with a two-nozzle design and ceramic components according to a second variant of the first preferred embodiment and a second variant of the second preferred embodiment, in which the nozzles are flat or at least elliptical. [Figure 6]1 shows a schematic longitudinal section of a hydrogen burner scheme with a two-nozzle design and ceramic components according to a second variant of the first preferred embodiment and a second variant of the second preferred embodiment, in which the nozzles are flat or at least elliptical. [Figure 7] FIG. 1 shows three schematic representations of hydrogen burners, each with an alternative nozzle cross-section: in (a) a cylindrical nozzle, in (b) an elliptical slot and in (c) a flat rectangular slot. [Figure 8A] FIG. 1 shows three diagrammatically illustrated examples of hydrogen burners each equipped with a cylindrical nozzle below which an additional injector is arranged for introducing additional purge gas as an oxygen-containing gas having more than 20% by weight of oxygen, where each injector is of a different shape, i.e. circular, rectangular and elliptical. [Figure 8B] Figure 3 shows three diagrammatically illustrated examples of hydrogen burners with rectangular nozzles in figures (a)(c) and (e) respectively and elliptical nozzles in figures (b)(d) and (f) respectively, below which are placed additional injectors of alternative combinations of shapes and positions for introducing an oxygen-containing gas having more than 20% by weight of oxygen, where each injector is of a different shape, i.e. circular, rectangular and elliptical. [Figure 9] FIG. 1 shows control schemes for supplying hydrogen and oxygen to the burners, including the use of control valves for a two-nozzle burner design, i.e., a two-nozzle hydrogen-oxygen burner shown in FIG. (a), and a three-nozzle hydrogen-oxygen burner, i.e., a three-nozzle hydrogen-hydrogen-oxygen burner shown in FIG. (b). [Figure 10] FIG. 1 illustrates a control scheme for hydrogen, oxygen and oxygen-containing gas having an O2 content greater than 20 wt. %, including the use of a control valve for a two-nozzle hydrogen-oxygen burner. [Figure 11] 1 is a graph showing the ratio between the heating burner power WCHEM and the fuel gas motive power WKIN at the nozzle outlet. [Figure 12]1 is a graph showing the temperature evolution in the burner ceramic parts related to the WRATIO at the nozzle exit. [Figure 13] FIG. 2 shows a flow chart of a preferred embodiment of a method for the combustion of hydrogen gas in an industrial furnace, i.e., a glass furnace or a metal melting furnace, with the aid of the preferred multi-nozzle burner described above.

[0101] The drawings are intended to illustrate and introduce examples of the invention and of the specific designs described subsequently, and are not intended in any way to limit the scope of protection defined by the claims, but merely to clarify the essence of the invention.

[0102] In the drawings, the physical technical background and essential features of the present invention are described with reference to Figures 11 and 12. Figures 11 and 12 are referred to throughout the detailed description and are common to all embodiments of the multi-nozzle burner shown herein. A flow chart of the essence of the method of operation of the inventive concept is shown in Figure 13, while an embodiment of the control method is shown in Figures 9 and 10. Figures 9 and 10 are also common to all embodiments of the multi-nozzle burner shown herein.

[0103] As a basis for this principle presented above, firstly various embodiments of a multi-nozzle burner for burning hydrogen gas in an industrial furnace will be described below with reference to Figs. 1 to 8. Figs.

[0104] Essentially, regarding the method of operating an industrial furnace, a multi-nozzle burner 100, 200, 300, 400 for hydrogen gas combustion in an industrial furnace 1000, particularly a glass furnace or metal melting furnace, is provided by a multi-nozzle burner 100, 200, 300, 400 with controllable flow of a hydrogen fuel gas composition and an additional gas composition, as shown in the examples of Figures 9 and 10.

[0105] First, in the following, Fig. 1, Fig. 2, Fig. 3, Fig. 4 are commonly referred to. For identical or equivalent items or items with identical or equivalent functions, the same reference symbols are used in the following. For corresponding features, reference is therefore made to the above description. In the following, where useful, in particular, differences between the embodiments of different figures are further described below with specific reference to Fig. 1, Fig. 2, Fig. 3, Fig. 4.

[0106] The gas stream is injected into the industrial furnace through a cavity 11 having an opening 12 to form a reaction mixture of hydrogen fuel gas composition H and additional gas composition O for combustion in the industrial furnace 1000. The cavity 11 in the embodiment described herein is within a refractory body 10, for example made of a ceramic block or some other refractory material, to form the furnace wall.

[0107] The set goals are achieved by the concept of the invention, which is a method for the combustion of hydrogen gas in an industrial furnace 1000, in particular a glass furnace or a metal melting furnace, with the aid of a multi-nozzle burner with controllable adjustment of the flow of hydrogen gas H and additional gas O.

[0108] It should be noted that the symbols used herein do not annotate the chemical structure of the gases unless otherwise specified. The chemical structure is not the focus of this application, and this can, of course, vary. In general, it is assumed herein that hydrogen, as gas H, consists of "H2" molecules, and oxygen gas O consists of "O2" molecules.

[0109] According to the inventive concept, the hydrogen fuel gas composition is formed by a first fuel gas component of 80% by weight or more of hydrogen gas and 20% by weight or less of another fuel gas or gas component other than hydrogen gas; The additional gas composition is preferably formed by a first oxidant gas component which contains oxygen or air, in particular has an oxygen content of more than 80% by weight.

[0110] In this embodiment, the hydrogen fuel gas composition H is formed by a first fuel gas component of hydrogen gas "H2" that is 80% by weight or more and another fuel gas component other than hydrogen gas "H2" that is 20% by weight or less.

[0111] The additional gas composition O is formed by a first oxidant gas component of oxygen or air having an oxygen content of more than 80% by weight or another oxidant having an oxygen content of more than 80% by weight and not more than 20% by weight of oxygen or another oxidant gas component other than air. More broadly, in this specification, the term hydrogen gas H means in particular any gas containing 80% by weight or more of hydrogen "H2".

[0112] In this particularly preferred embodiment, the hydrogen fuel gas composition is formed by mostly pure hydrogen gas with unavoidable impurities, and the additional gas composition is formed by mostly pure oxygen gas with unavoidable impurities, in particular hydrogen gas and oxygen gas originating from a water electrolysis process. In most cases, this constitutes a fuel gas composition comprising more than 95% by weight of hydrogen gas, in particular more than 99% by weight of hydrogen gas, and an additional gas composition comprising more than 95% by weight of oxygen gas, in particular more than 99% by weight of oxygen gas. As shown in the first and second embodiments in Figures 1 and 2, the hydrogen fuel gas composition H is introduced into the cavity 11 from the multi-nozzle burner 100, 200. Furthermore, the reaction gas mixture of the hydrogen fuel gas composition H and the additional gas composition O is injected from the tip T of the burner nozzle into the cavity 11 and from there into the furnace space at a high internal temperature (for example, 1400 ° C to 1650 ° C) through the opening 12. The tip T can be flush with the refractory block 10, as can be seen in FIG. 1 or FIG. 2, or can be inserted therein, as can be seen, for example, in FIG.

[0113] In all embodiments, the central flow of gas HM is from one central gas nozzle 1 with simultaneous injection of at least one independent further flow of additional gas composition OC from one concentric gas nozzle 3, which in both the embodiments of Figures 1 and 2 is a peripheral gas nozzle.

[0114] Thus, the central flow of gas of hydrogen fuel gas composition H in both the FIG. 1 and FIG. 2 embodiments is surrounded by a concentric flow of gas of additional gas composition O.

[0115] Thus, the essence of a multi-nozzle burner in this specification is that hydrogen gas or gas composition H is injected into the cavity 11 of the burner 100, 200 through at least one central gas nozzle 1 with the simultaneous injection of one independent flow of additional gas O or additional gas composition O such that the hydrogen fuel gas H is surrounded by concentric flows of the additional gas O through the concentric gas nozzles 3 as peripheral gas nozzles.

[0116] The integral central opening 1M of the central tube M of each central gas nozzle 1 opens it for a central flow of gas HM into the cavity 11. The annular peripheral opening 3P of the concentric peripheral tube CP of each concentric gas nozzle 3 opens it for a concentric flow of gas OC into the cavity 11. The peripheral flow and the peripheral nozzle are to be understood as the gas flow and the flow at the periphery of the respective nozzle, that is to say the peripheral tube CP of the outer part of the burner. By using this peripheral tube CP of the outer part of the burner for the primary additional gas composition according to the concept of the invention, said kind of envelopment of the central flow of the relatively light hydrogen fuel gas by the surrounding and surrounding relatively heavy primary additional gas composition is established. For this reason, the space inside the central tube M is used for the hydrogen fuel gas composition H, which is formed by at least 80% by weight or more of a first fuel gas component of hydrogen gas and not more than 20% by weight of another fuel gas or gas component other than hydrogen gas. The space within the concentric peripheral tube CP is used in this embodiment for an additional gas composition formed by a first oxidizer gas component, which is oxygen having an oxygen content of more than 80% by weight or another oxidizer having an oxygen content of more than 80% by weight and another oxidizer gas component other than oxygen having 20% ​​by weight or less, for example an oxidizer gas component other than oxygen, such as air or another gas.

[0117] In particular, the embodiment in Fig. 1 shows a hydrogen burner 100 with two nozzles 1, 3 and a ceramic component 10. In this first particularly preferred development, the hydrogen fuel gas composition is introduced into the cavity 11 of the multi-nozzle burner 100 from at least one central gas nozzle 1 with the simultaneous injection of an additional gas composition OC, i.e. only a first independent further flow of the primary additional gas composition OC. This means that the central flow of gas HM of the hydrogen fuel gas composition H is surrounded by a concentric flow of gas OC of the primary additional gas composition O, more precisely called O1 in this specification. A further outer additional gas composition O2 can be provided by a further nozzle.

[0118] Alternatively, as shown in particular in the embodiment in FIG. 2, the hydrogen burner 200 can be designed with another concentric nozzle 2 arranged between the central nozzle 1 and the burner outer part, which is intended to provide a peripheral flow and a peripheral nozzle. The peripheral flow and the peripheral nozzle are to be understood as gas flows and flows at the periphery of the respective nozzle, so to speak, the peripheral tube CP of the burner outer part, and thus the concentric gas nozzle 3 as the peripheral gas nozzle shown in FIG. 2. This establishes the scheme of the hydrogen burner 200 with three nozzles and a ceramic part for establishing the refractory block 10. The concentric tube CM of each separate concentric gas nozzle 2 has an annular intermediate opening 2C, which opens the other concentric gas nozzle 2 for a further concentric flow of gas into the cavity 11. The annular peripheral opening 3P of the concentric peripheral tube CP of each concentric gas nozzle 3 again opens the concentric gas nozzle 3 for a concentric flow of gas OC into the cavity 11.

[0119] For this purpose, in Fig. 2 a hydrogen burner 200 is shown with three nozzles 1, 2, 3 and a ceramic part 10. In this second particularly preferred development, the hydrogen fuel gas composition H is introduced into the cavity 11 of the multi-nozzle burner 200 from at least one central gas nozzle 1 with the simultaneous injection of an additional gas composition OC, i.e. only a first independent further flow of the primary additional gas composition OC. This means that the central flow of gas HM of the hydrogen fuel gas composition H is surrounded by a concentric flow of gas OC of the primary additional gas composition O, more precisely called O1 in this specification. A further additional gas composition O2 can be provided by a further nozzle.

[0120] In this embodiment, the central flow HM of hydrogen gas H from the central nozzle 1 is surrounded by two concentric flows of gas, firstly H or O which further enter the combustion process from the annular intermediate opening 2C and respectively a primary additional gas O1 which enters the combustion process from a peripheral opening 3P. The peripheral opening 3P for the primary additional gas is used for oxygen and / or gases with an oxygen content of at least 80% by weight.

[0121] In a first concept of this embodiment (not shown here), the opening 1M - which is a fully shaped central opening 1M - is used for hydrogen gas or a hydrogen gas composition H containing at least 80% by weight of hydrogen, and the opening 2C - which is a ring-shaped intermediate opening 2C - is used for oxygen and / or a gas having an oxygen content of at least 80% by weight.

[0122] Thus, in an embodiment according to the first concept, the hydrogen fuel gas composition is preferably introduced into the cavity of the multi-nozzle burner through at least one central gas nozzle with simultaneous injection of at least first and second independent further flows of additional gas composition, - a central flow of gas of the hydrogen fuel gas composition H is surrounded by a concentric flow of gas of a peripheral primary additional gas composition O1; - the concentric flow of gas of the primary additional gas composition surrounds a concentric flow of gas of the secondary additional gas composition that is between the central flow of gas of the hydrogen fuel gas composition and the concentric flow of gas of the primary additional gas composition.

[0123] Preferably, in the second embodiment according to the first concept, b2) The gas momentum per second of the concentric flow of the secondary additional gas composition at the outlet of the concentric gas nozzle is 0.01 to 10.4 [kgO2 m / s 2 It is provided that the range is .

[0124] In a second concept of this embodiment (shown in FIG. 2), the openings 1M, 2C, which are a full-shaped central opening 1M and an annular-shaped intermediate opening 2C, are used for hydrogen gas or a hydrogen gas composition H containing at least 80% by weight hydrogen.

[0125] For this reason, in a second particularly preferred development of the second concept with reference to FIG. 2, the hydrogen fuel gas composition is preferably introduced into the cavity of the multi-nozzle burner: a central flow of gas of the hydrogen fuel gas composition from at least one central gas nozzle and a concentric flow of gas of the hydrogen fuel gas composition from at least one further concentric gas nozzle; with simultaneous injection of at least one independent further flow of at least one additional gas composition from at least one concentric gas nozzle; - a central flow of gas of the hydrogen fuel gas composition is surrounded by concentric flows of gas of the hydrogen fuel gas composition; - The concentric flow of gas of the hydrogen fuel gas composition is surrounded by a concentric flow of the primary and / or secondary additional gas composition.

[0126] Preferably, in a second development of the second concept, a2) the gas momentum per second of the concentric flow of the hydrogen fuel gas composition at the outlet of the concentric gas nozzle is between 0.001 and 1.2 [kgH2m / s 2 It is provided that the range is .

[0127] FIG. 3 shows a cross-sectional view of a preferred embodiment of a multi-nozzle burner 100, 200 according to the first and second embodiments, which in principle also relate to the third and fourth embodiments of the invention described in FIGS. 5 and 6.

[0128] It can be seen that preferably the reaction mixture of the hydrogen fuel gas composition H and the additional gas composition O is led into the furnace through a cavity in the ceramic part 10, in particular through a cavity 11 provided in the ceramic wall of the furnace. This achieves a modern and flexible installation of the burner in the furnace. In a particularly preferred development, the reaction mixture of the hydrogen fuel gas composition H and the additional gas composition O is led into the furnace 1000 through the cavity 11, the ratio between the circumference of the burner cross section and the circumference of the cavity cross section being in the range of 0.95 to 1.05.

[0129] In Fig. 4 a burner 100, 200, 300, 400 for gas combustion in an industrial furnace 1000 is shown, consisting of an injection tube body 501 and a moulded part 510 fixed at the outlet of the injection tube body 501. The moulded part 510 comprises said cavity 11, the injection tube body 501 being provided with the above-mentioned inner gas nozzles 1, 2, 3 for the input of hydrogen fuel gas H. The central gas nozzle 1 for the central flow of gas HM into the cavity 11 is optionally surrounded by first and / or second concentric gas nozzles 2, 3 for the input of further hydrogen fuel gas H2 and / or secondary additional gas O2, as explained in Fig. 2 and Fig. 6. However, as described above with respect to FIG. 1, in each case the hydrogen fuel gas composition is introduced into the cavity 11 from a multi-nozzle burner by a central flow of gas HM from at least one central gas nozzle 1 with the simultaneous input of at least one independent further flow of additional gas composition O from at least one concentric gas nozzle 3, the central flow of gas HM of the hydrogen fuel gas composition H being surrounded by a concentric flow OC of gas of the primary additional gas composition, in particular the concentric flow of gas of the primary additional gas composition OC being a peripheral concentric flow of gas. This means that in each case the central gas nozzle 1 is surrounded by a concentric gas nozzle 3 for the input of additional gas O, which forms the outer body of the injection tube body 501. The nozzle tip T is located in the cavity 11 or at its very beginning. Here, all the nozzles and openings 1M, 2C, 3P are coplanar in one and the same plane.

[0130] Figure 4 - a three-dimensional view of the preferred embodiment of Figure 3 - shows the burner 500 of Figure 3. The injection tube body 501 is fixed to the molded part 510 by a fixing device.

[0131] In FIG. 5, a schematic longitudinal section of a hydrogen burner scheme with a two-nozzle design as in the embodiment of FIG. 1 is shown with the same reference numerals, showing a ceramic part according to a second variant of the first preferred embodiment. In the second variant, the nozzle is flat and at least elliptical. The explanations of FIG. 1 and FIG. 3 as well as FIG. 4 also apply to FIG. 5. It has been shown that a flat and at least elliptical nozzle has advantages. This is described in detail in WO2020 / 078775, the disclosure of which is incorporated herein by reference.

[0132] In FIG. 6, a schematic longitudinal section of a hydrogen burner scheme with a three-nozzle design as in the embodiment of FIG. 2 is shown with the same reference numerals, showing a ceramic part according to a second variant of the second preferred embodiment. In the second variant, the nozzle is flat and at least elliptical. The explanations of FIG. 2 and FIG. 3 as well as FIG. 4 also apply to FIG. 6. It has been shown that a flat and at least elliptical nozzle has advantages. This is described in detail in WO2020 / 078775, the disclosure of which is incorporated herein by reference.

[0133] Furthermore, since the reaction gas mixture has to be injected from the burner tip into the furnace space with high internal temperatures (e.g. 1400°C-1650°C), it is essential that such reaction gas flow passes through a ceramic part 10 or ceramic furnace wall having openings 12. The openings 12 can be either in the form of a cylinder as shown in Figures 7A and 1 or in the form of an elliptical slot as shown in Figures 7B and 2 or in the form of a flat rectangular slot as shown in Figure 7C. In this way, the heat from the furnace radiation and the heat generated by the hydrogen-oxygen combustion are combined and isolated from the burner parts.

[0134] With respect to Table I, it has been further observed that there are certain burner operating and burner geometric parameters (called key parameters) that need to be observed and maintained with certain margins to achieve flame stability and avoid overheating of the burner structure and associated furnace materials.

[0135] Such key parameters relate at most to the mixing rate of the hydrogen fuel gas composition, in particular the hydrogen fuel gas, on the one hand, but also to the mixing rate with additional gas compositions, in particular oxygen gas, on the other hand. The latter can be addressed by the values ​​of the momentum per second of the hydrogen gas flow and the momentum per second of the oxygen gas flow as two important figures of merit. These key parameters are optionally also related to the turbulence in the burner and in the flame.

[0136] Moreover, said main parameter is at most related to the ratio between the burner heating power [kW] and the combustion process dynamics: the latter can be addressed as a further figure of merit by the value of the ratio of the heating burner power (WCHEM [W]) to the kinetic power of the hydrogen fuel gas composition (WKIN [W]).

[0137] Extensive parametric computational fluid dynamics calculations, along with combustion chemistry and turbulence modeling, have been used to determine such burner operating and design parameters and associated values ​​of figures of merit.

[0138] It follows from Table I that at least the values ​​of the above mentioned performance indices are useful for addressing the following physical variables that must be taken into account in order to address the beneficial operation of the multi-nozzle burner according to the concept of the invention, i.e., for an improved method of hydrogen combustion and an improved design of a hydrogen-fired burner for the realization of an improved hydrogen combustion method, mainly in terms of flame control that prevents overheating of the furnace, being observed. For this reason, in order to address the main physical variables mentioned above, the relevant performance indices are at least: - the momentum per second of the hydrogen gas flow for each hydrogen fuel gas composition;

number

[0139] - momentum per second of the oxygen gas flow for each additional gas composition

number

[0140] - the ratio of the heating burner power (WCHEM [W]) to the kinetic power of the hydrogen fuel gas composition (WKIN [W]) Includes. [Table 1]

[0141] Furthermore, the relevant values ​​of the figures of merit for the above mentioned key parameters are as follows: a) Hydrogen gas momentum per second

number

[0142] This refers to the hydrogen fuel gas momentum per second at the outlet of the central gas nozzle 1, i.e., at the central opening 1M in its complete shape, as shown, for example, in the first embodiment shown in Figures 1 and 5. This also refers to the hydrogen fuel gas momentum per second at the outlet of the central gas nozzle 1, i.e., at the central opening 1M in its complete shape, as shown, for example, in the second embodiment shown in Figures 2 and 6, respectively.

[0143] Further, this indicates, for example, the hydrogen fuel gas momentum per second at the outlet of the concentric gas nozzle 2, i.e. the annular shaped intermediate opening 2C, as shown in the second embodiment shown in Figures 2 and 6, respectively, with respect to the second operating concept, where the hydrogen fuel gas composition is introduced into the cavity of the multi-nozzle burner by a central flow of gas of the hydrogen fuel gas composition from at least one central gas nozzle and a concentric flow of gas of the hydrogen fuel gas composition from at least one further concentric gas nozzle.

[0144] Here, the hydrogen gas momentum per second as the first figure of merit is preferably 0.001 to 1.2 [kgH2m / s 2 ] range.

[0145] b) Oxygen gas momentum per second

number

[0146] This indicates, for example, in the first embodiment, the gas momentum per second of the concentric flow of the primary additional gas composition at the outlet of the concentric gas nozzle 3, i.e., the annular shaped peripheral opening 3P, for the concentric flow of gas OC into the concentric gas nozzle cavity 11, as shown in Figures 1 and 5.

[0147] This also indicates, for example, the gas momentum per second of the concentric flow of the secondary additional gas composition at the outlet, i.e., the annular intermediate opening 2C, in the second embodiment, as shown in the second embodiment shown in Fig. 2 and Fig. 6, for the first operating concept. The hydrogen fuel gas composition is introduced into the cavity of the multi-nozzle burner from at least one central gas nozzle with the simultaneous injection of at least first and second independent further flows of the additional gas composition. The central flow of gas of the hydrogen fuel gas composition H is surrounded by the concentric flow of gas of the primary additional gas composition O1 at the periphery, which surrounds the concentric flow of gas of the secondary additional gas composition between the central flow of gas of the hydrogen fuel gas composition and the concentric flow of gas of the primary additional gas composition.

[0148] The primary and / or secondary additional gas compositions O1, O2, in particular oxygen gas or gases containing more than 80% by weight of oxygen, are given the following as a second figure of merit: 0.01~10.4[kgO2m / s 2 ] per second at the outlet of the concentric gas nozzle 3 or another concentric gas nozzle 2 in the range of

[0149] c) Relationship between heating burner output and kinetic force of hydrogen gas flow The relationship between heating burner power and fuel kinetic power, characterizing the trend towards optimal burner performance, is shown in FIG. 11. FIG. 11 shows the relationship between heating burner power WCHEM on the y-axis and fuel gas kinetic power WKIN on the x-axis. Unlike "natural gas-oxygen" combustion, the relationship for "hydrogen-oxygen" combustion was found to occur on a significantly different scale, as can be seen from the comparison of the "natural gas-oxygen" combustion curve NG-O with the "hydrogen-oxygen" combustion curve HO in FIG. 11.

[0150] This difference in the ratio between WCHEM and WKIN can be translated into a value as the ratio WRATIO, which is the third figure of merit and affects the flame temperature, i.e., the temperature in the vicinity of the burner body and ceramic component 10 as previously described.

[0151] To illustrate this effect, the temperature trends related to the ratio between WCHEM and WKIN, translated into values ​​as the ratio WRATIO, are shown in Figure 12. In Figure 12, the temperature evolution in the burner ceramic parts is shown as a function of temperature T related to the ratio WRATIO as a figure of merit, i.e. depending on the value of the ratio WRATIO.

[0152] The optimum region of the combustion process is read from the region when the function of temperature T depending on WRATIO reaches its minimum value. It is achieved when the ratio of the chemical burner power WCHEM to the kinetic energy of hydrogen gas WKIN [W] is in the range WRATIO = 100000 - 4.000.000 [1].

[0153] Thus, in summary, when a hydrogen fuel gas composition is introduced into a cavity from a multi-nozzle burner by a central flow of gas from at least one central gas nozzle with simultaneous introduction of at least one independent additional flow of additional gas composition from at least one concentric gas nozzle: - the central flow of gas of the hydrogen fuel gas composition is surrounded by a concentric flow of gas of the primary additional gas composition, in particular the concentric flow of gas of the primary additional gas composition is a peripheral concentric flow of gas. a1) The gas momentum per second of the central flow of the hydrogen fuel gas composition at the outlet of the central gas nozzle is 0.001 to 1.2 [kgH2m / s 2 ] range, b1) The gas momentum per second of the concentric flow of the primary additional gas composition at the outlet of the concentric gas nozzle is 0.01 to 10.4 [kgO2 m / s 2 ] range, c) A trend towards optimized operation is ensured if the ratio of the heating burner power (WCHEM [W]) to the kinetic power of the hydrogen fuel gas composition (WKIN [W]) is in the range WRATIO = 100.000 to 4.000.000 [1].

[0154] The implementation of the above-mentioned examples of the present invention will now be described in more detail.

[0155] As further illustrated with respect to Figures 1-7, these detailed and general functional aspects of the above key hydrogen burner parameters can be applied to several burner design concepts having specific geometries.

[0156] As shown in FIG. 4, the concentric nozzles of the hydrogen-oxygen burners 100, 200 are cylindrical as in the first embodiment of the burner design as shown in FIGS. 1 and 2, yet the relevant characteristics also apply to the flat nozzles of the hydrogen-oxygen burners 300, 400.

[0157] For this reason, the multi-nozzle burners 100, 200, 300, 400 typically comprise an injection tube of a central tube CM within an injection tube body 501 of a peripheral tube CP, and thus the burner outer part is essentially the above-mentioned peripheral concentric tube CP, which is fixed to the outer wall of the injector and is formed so that the diameter of its inner cylindrical cavity 10 basically corresponds to the outer diameter of the body of the injection tube body 501.

[0158] The injection tube body 501 of the peripheral tube CP is surrounded by a concentric nozzle formed by the burner outer part of the peripheral concentric tube CP, which is provided with a main regulating valve for the inlet IH of hydrogen fuel gas for input and a regulating valve for the inlet IO of an additional gas, which in this example is oxygen.

[0159] The hydrogen fuel gas enters the combustion process through openings 1M or 1M and 2C, i.e. from a central nozzle 1 or from a central nozzle 1 and a concentric gas nozzle 2, as described above with respect to the first and second embodiments shown in Figures 1 / 5 and 2 / 6, respectively. The latter is the case when a central and concentric flow of hydrogen fuel gas composition is provided, surrounded by a single primary additional gas composition.

[0160] The additional gas composition, in particular the primary gas of oxygen, enters the combustion process in both above mentioned cases through opening 3P, and optionally, in the first concept, through opening 2C between the central nozzle 1 and the concentric gas nozzle 2. This is the case when only a single flow of hydrogen fuel gas composition is provided, surrounded by secondary and primary additional gas compositions.

[0161] A reaction mixture of hydrogen and oxygen is conducted through the cylindrical cavity 11 and through the ceramic component 10 into the furnace.

[0162] It is advantageous for the ratio between the diameter of the burner outer part of the peripheral concentric tube CP and the diameter of the opening 12 of the ceramic part to be in the range of 0.95 to 1.05, and for the ratio between the diameter of the burner outer part of the peripheral tube CP and the length L1 of the ceramic part 10 to be in the range of 2.0 to 5.0.

[0163] Furthermore, the hydrogen injection velocity vH2 into the refractory ceramic part 10 is a value of 5 to 85 m / s, in particular a velocity of less than 40 m / s. Furthermore, the first primary additional gas is oxygen, the value of its injection velocity into the ceramic part in a controllable capacity for stoichiometric combustion of the hydrogen fuel gas is in accordance with the following relationship: VH2:vO2=1:(0.3~1.8) is given by:

[0164] In the optimal case, the amount and rate of the input hydrogen gas and the temporary additional gas are continuously controllable, and as the fuel gas, pure hydrogen or hydrogen in a mixture with other hydrocarbons and gases (i.e., having an H2 content of at least 80% by weight or more) is used equally well, and as the additional gas, oxygen, air or another oxidant having an oxygen content of at least 80% by weight or more is used.

[0165] Similarly, the flow cross-sectional area of ​​the hydrogen fuel gas central nozzle, given by the area of ​​the opening of the central gas nozzle 1, and the flow cross-sectional area of ​​the additional gas stream, which is the annular cross-section of the opening, is related as follows:

number

[0166] As shown, with the hydrogen-oxygen burner design having three concentric cylindrical nozzles in the second embodiment, the burner design shown in Figures 2 and 6 comprises similar features as those described above.

[0167] Thus, the burner designs described in Figures 1 and 5, respectively, can be extended with additional concentric nozzles as shown in Figures 2 and 6, respectively.

[0168] The burner then comprises an injection tube of the central tube M with said central gas nozzle 1 for a central flow of gas HM into the cavity 11, a burner outer part of a concentric peripheral tube CP with a concentric gas nozzle 3 for a concentric flow of gas OC into the cavity 11, and a concentric tube CM of an additional concentric gas nozzle 2 with an annular intermediate opening 2C and opening another concentric gas nozzle 2 for a further concentric flow of gas into the cavity 11. For this reason, the concentric tube CM of the additional concentric gas nozzle 2 is arranged between the inner injection tube of the central tube M on the one hand and the outer burner outer part of the concentric peripheral tube CP with the concentric gas nozzle 3 for a concentric flow of gas OC into the cavity 11 on the other hand, thus forming another duct for the additional gas. The injection tube of the central tube M is again surrounded by a concentric nozzle with a main regulating valve for the input of a hydrogen fuel gas inlet IH and with a regulating valve for the input of an additional oxygen fuel gas inlet IO. This concentric nozzle is further surrounded by a burner outer part which is provided with a regulating valve for the introduction of another inlet IO of additional gas - oxygen.

[0169] In a first concept of this embodiment (not shown), the opening 1M - which is a fully shaped central opening 1M - is used for hydrogen gas or a hydrogen gas composition H containing at least 80% by weight of hydrogen, and the opening 2C - which is a ring-shaped intermediate opening 2C - is used for oxygen and / or a gas having an oxygen content of at least 80% by weight.

[0170] Thus, in the first operating concept, hydrogen fuel gas enters the combustion process through the opening 1M of the injection tube, secondary additional gas enters the combustion process through the opening 2C between the injection tube of the central tube M and the peripheral concentric gas nozzle 3P, and primary additional gas of oxygen enters the combustion process through the peripheral opening 3P between the concentric nozzle 2C and the burner outer part of the peripheral concentric tube CP.

[0171] On the other hand, in the second operating concept, more hydrogen fuel gas is available and so enters the combustion process through the opening 1M of the injection tube in the form of a central tube M by means of a central gas nozzle 1M, further hydrogen fuel gas enters the combustion process through the opening 2C between the injector of the central tube M and the peripheral concentric nozzle 3P and through the peripheral gas nozzle 3P, and additional gas enters the combustion process through the opening 3P between the concentric nozzle 2C and the burner outer part.

[0172] A reaction mixture of hydrogen and oxygen is conducted through the cylindrical cavity 11 and through the ceramic component 10 into the furnace.

[0173] It is advantageous that the ratio between the diameter of the burner outer part 2 and the diameter of the opening 12 in the ceramic part is in the range of 0.95 to 1.05, and the ratio between the burner outer diameter of the peripheral tube 3P and the length L1 of the ceramic part 10 is in the range of a ratio of 2 to 5.

[0174] Furthermore, the input velocity vH2 of the primary additional gas, which is hydrogen from the central nozzle 1 or from the central nozzle 1 and the concentric gas nozzle 2C and also passing through the opening 3P, alternatively according to the first concept also 2C, to the ceramic part is a value of 5 to 85 m / s, in particular less than 40 m / s, while the secondary additional gas is oxygen, the value of its input velocity to the ceramic part in the controllable capacity for the stoichiometric combustion of the fuel gas is in accordance with the following relationship: VH2:vO2=1:(0.3~1.8) is given by:

[0175] In the optimal case, the amount and rate of the input hydrogen gas and the secondary additional gas can be continuously controlled, and as fuel gas pure hydrogen or hydrogen in a mixture with other hydrocarbons and gases is used, and as additional gas oxygen, air or another oxidant with an oxygen content of 80% by weight is used.

[0176] Similarly, the cross-sectional area of ​​the flow of the hydrogen fuel gas central nozzle 1 and the cross-sectional area of ​​the primary additional gas are determined by the sum of the areas of the openings 3P alone or by the sum of the areas of the openings 1M and 2C,

number

number

[0177] With reference to Figures 8A and 8B, alternative shapes of burner cross sections are shown in a new embodiment. As explained, a hydrogen-oxygen burner can be designed using a cylindrical nozzle as seen in Figures 1 and 2 and 7(a) where the flame is directed through a cylindrical cavity 11 in a ceramic part 10 into a glass furnace or other industrial furnace.

[0178] In summary, it can be seen that it has further been discovered that the hydrogen-oxygen burner design can be modified such that the cross-section of the burner nozzle and associated ceramic component openings are either flat rectangular slots or elliptical slots, as shown in Figures 5 and 6 and Figures 7(b) and (c). Indeed, Figure 7 shows alternative nozzle cross-sections for a hydrogen burner having 7(a) a cylindrical nozzle, 7(b) an elliptical slot or 7(c) a flat rectangular slot.

[0179] For each multi-nozzle burner, at least one purge-injector body 600C, 600R, 600S is provided, passing through the ceramic part 10, as shown here in Figs. 8A and 8B, - the purge-injector body 600C, 600R, 600S introduces an additional gas flow, preferably an additional gas flow of oxygen or an additional gas flow containing a purge gas containing more than 20% by weight of oxygen, into the industrial furnace; - By introducing an additional gas flow, the water vapor-rich zone of the hydrogen flame of the reaction mixture is separated from the molten material in the furnace.

[0180] Hydrogen-oxygen flames produce high concentrations of water vapor. H2+1 / 2O2 → H2O

[0181] By means of the purge injector bodies 600C, 600R, 600S introducing additional gas flow, preferably an additional gas flow containing oxygen or a purge gas containing more than 20% by weight oxygen, is introduced into the industrial furnace to provide protection for the glass melt from the effects of water vapor.

[0182] Such a high concentration of water in the furnace atmosphere can adversely affect the molten material, such as glass properties and behavior. It is therefore beneficial to add another purge-injector body 600C, 600R, 600S or injector passing through the ceramic component 10, which allows the introduction of additional gas into the combustion process. The purpose of this additional purge-injector body 600C, 600R, 600S or injector is to add an oxygen-containing gas with more than 20% oxygen by weight, so as to separate the water vapor-rich zone of the flame from the molten material in the furnace. The arrangement of such an additional injector of oxygen is shown in FIG. 8A. FIG. 8A shows a first example of the shape and position of the additional injector 600C, 600R, 600S for the introduction of an oxygen-containing gas with more than 20% oxygen by weight.

[0183] This example in FIG. 8A shows the case where the burner cross section is cylindrical, but oxygen-containing gas (greater than 20 wt. % O2) is introduced below the burner from additional purge-injector bodies 600C, 600R, 600S having alternative cross-sectional shapes such as cylindrical in (a), elliptical slots in (b) or flat rectangular slots (c) as shown in FIG. 8A.

[0184] As explained above, the burner cross-sectional shape can have three main types - cylindrical, elliptical slot or flat rectangular slot. These shapes can be freely combined with additional oxygen-containing gas injectors 600C, 600R, 600S of all three shapes (cylindrical, elliptical and flat rectangular) as seen in Fig. 8B under burners 100, 200, 300, 400, respectively. Fig. 8B shows a second example of an alternative combination of shapes and positions of additional injectors 600C, 600R, 600S for the introduction of oxygen-containing gas, e.g. air or enriched air or similar oxygen-containing gas containing more than 20% oxygen by weight.

[0185] In Figures 9 and 10, control of hydrogen gas, primary additional gas and secondary additional gas is illustrated for multi-nozzle burners 100, 200, 300, 400 which are applicable to either method.

[0186] A burner for hydrogen gas combustion in an industrial furnace, in particular a glass furnace or a metal melting furnace, shown in Figures 1 and 5, comprises an injection tube as a central tube M and a burner outer part as a peripheral tube CP. Such a type of multi-nozzle burner is fixed at the outlet of the cavity and is provided with regulating valves for the gas input of hydrogen and primary additional gas, i.e. formed as a two-nozzle burner 100, 300 shown in position (a) in Figures 1, 3 and 9.

[0187] The burner 200, 400 according to Fig. 2, Fig. 6 for hydrogen gas combustion in industrial furnaces, in particular glass furnaces or metal melting furnaces, comprises an injection tube as a central tube M1 and a burner outer part as a peripheral tube CP of the burner, with an additional nozzle 2C inserted between the central nozzle 1M and the burner outer part nozzle 3P. The burner comprises a main regulating valve for the input of hydrogen fuel gas, i.e. as shown in the three-nozzle burner 200, 400 and in position (b) of Fig. 9, and an auxiliary valve for the input for the control of the primary and secondary additional gas through the spaces 2C and 3P, respectively.

[0188] Furthermore, it is then advantageous if the regulating valve of the primary additional gas inflow and the regulating valve of the secondary additional gas inflow are controlled via an additional gas control unit connected to the control block of the combustion process. Also via the hydrogen fuel gas control unit, the main regulating valve of the hydrogen fuel gas inflow is connected to the auxiliary regulating valve, while the control block of the combustion process is connected to the evaluation and control block with the control element, as also shown in position (a) in FIG. 9 and in FIG. 9(b).

[0189] FIG. 9 shows a hydrogen and oxygen gas control scheme involving the use of control valves for a) the two-nozzle hydrogen-oxygen burners 100,300 and b) the three-nozzle hydrogen-oxygen burners 200,400.

[0190] This scheme is also applicable to controlling the oxygen input of burners 100, 200, 300, 400 for oxygen-containing gases containing more than 20% oxygen by weight from additional injectors 600C, 600R, 600S.

[0191] 10 shows a control scheme for hydrogen, oxygen and oxygen-containing gases with O2 content greater than 20 wt. % including the use of control valves for a two-nozzle hydrogen burner similar to that of burners 100, 300. Moreover, this scheme can also be extended to three-nozzle hydrogen burners 200, 400 at the top.

[0192] The purpose of the additional one or more injectors 600C, 600R, 600S in the lower part of Fig. 10 for oxygen-containing gas with more than 20% oxygen by weight is to control the total amount of oxygen-containing gas. With respect to the use of purge gas, it is further beneficial to control the oxygen-containing gas passing through this injector by a separate valve, as shown in Fig. 10 and previously described in Figs. 8A and 8B. To maintain stoichiometric combustion and a desired excess of oxygen in the fuel gas, it is beneficial to control this oxygen-containing gas with an O2 content of more than 20% by weight, either independently or depending on the total amount of oxygen in the combustion process.

[0193] Furthermore, it is then advantageous if the regulating valve of the inflow of the oxygen-containing gas and the regulating valve of the inflow of the primary or secondary additional gas are implemented via a control unit for the additional gases, which is connected to the control block of the combustion process. Also, via the control unit for the hydrogen fuel gas, the main regulating valve of the inflow of the hydrogen fuel gas is connected to the auxiliary regulating valve. The control block of the combustion process is connected to the evaluation and control block with the control elements shown in FIG.

[0194] The control block of the combustion process is further connected to a furnace camera operating in the visible and infrared parts of the spectrum, which allows recording of the batch position and allows collection of spectral data from the combustion process used for burner control.

[0195] With this proposed solution, new and higher effects are achieved in that with a very simple structural layout it is possible to achieve precise setting of the combustion process with high radiation efficiency and low NOx emissions. The continuous controllable input of hydrogen fuel gas and additional gases allows precise and gentle setting of the flame shape and motion, allowing sufficient adjustability of the flame, affecting NOx generation and preventing overheating of the burner and furnace structure.

[0196] For example, the process for gas combustion of hydrogen gas or mixtures of hydrogen with other gases, including hydrocarbons, i.e. with the aid of oxygen or air, and the burners for carrying out this process are intended for use in industrial furnaces, all of the above mentioned glass furnaces or metal melting furnaces.

[0197] FIG. 13 shows a flow chart of a preferred embodiment of a method for burning hydrogen gas in an industrial furnace, i.e., a glass furnace or a metal melting furnace, with the aid of the preferred multi-nozzle burners 100, 200, 300, 400 described above.

[0198] A method is disclosed having operational method steps for combusting hydrogen gas in an industrial furnace, particularly a glass furnace or metal melting furnace, by a multi-nozzle burner with controllable flow of a hydrogen fuel gas composition and an additional gas composition through a cavity into the industrial furnace to form a reaction mixture of the hydrogen fuel gas composition and an additional gas composition for combustion in the industrial furnace.

[0199] The method provides, in step S1, forming a hydrogen fuel gas composition. The hydrogen fuel gas composition is formed by a first fuel gas component of at least 80% by weight of hydrogen gas and at most 20% by weight of another fuel gas component other than hydrogen gas.

[0200] The method provides for forming an additional gas composition in step S2, the additional gas composition being formed by a first oxidant gas component of oxygen or air having an oxygen content of more than 80% by weight or another oxidant having an oxygen content of more than 80% by weight and up to 20% by weight of another oxidant gas component other than oxygen or air.

[0201] According to operation S3, a central flow of gas of the hydrogen fuel gas composition is provided which is surrounded by a concentric flow of gas of the primary additional gas composition in operation S4.

[0202] In step S5, the hydrogen fuel gas composition is introduced into the cavity from the multi-nozzle burner by a central flow of gas from at least one central gas nozzle with simultaneous introduction of at least one independent additional flow of additional gas composition from at least one concentric gas nozzle.

[0203] It is clear that the figure of merit according to conditions (a1) and (b1) and (c) and optionally additionally (a2) or (b2) is carried out as follows:

[0204] In step S6, in accordance with condition (a1), the gas momentum per second of the central flow of the hydrogen fuel gas composition at the outlet of the central gas nozzle is 0.001 to 1.2 [kgH2m / s2 ] range, Optionally, additionally, in the above mentioned second development of the second concept, it is provided that, according to condition (a2), the gas momentum per second of the concentric flow of the hydrogen fuel gas composition at the outlet of the further concentric gas nozzle is between 0.001 and 1.2 [kgH2m / s 2 It is provided that the range is .

[0205] In step S7, according to condition (b1), the gas momentum per second of the concentric flow of the primary additional gas composition at the outlet of the concentric gas nozzle is 0.01 to 10.4 [kgO2 m / s 2 ] range. Optionally, additionally, in the above mentioned second development of the first concept - instead of the second concept - according to condition (b2), the gas momentum per second of the concentric flow of the secondary additional gas composition at the outlet of the further concentric gas nozzle is between 0.01 and 10.4 [kgO2 m / s 2 It is provided that the range is .

[0206] In step S8, according to condition (c), the ratio of the heating burner power (WCHEM [W]) to the kinetic power of the hydrogen fuel gas composition (WKIN [W]) is in the range of WRATIO = 100.000 to 4.000.000 [1].

[0207] In step S9, the reaction mixture of the hydrogen fuel gas composition and the additional gas composition is combusted in an industrial furnace for glass or metal melting.

[0208] Thus, in summary, the embodiments described above can be generally outlined by the following embodiments.

[0209] 1. A method for burning hydrogen gas in industrial furnaces, in particular glass furnaces or metal melting furnaces, with the aid of a multi-nozzle burner with a controllable flow of hydrogen fuel gas (hydrogen gas means any gas containing 80% by weight or more H2) and nozzles of additional gas, in which the hydrogen fuel gas is introduced into the cavity of the burner by at least one central gas nozzle, with the simultaneous injection of at least one independent flow of additional gas, in such a way that the fuel gas is surrounded by a concentric flow of the primary additional gas, e.g. a) The momentum of hydrogen fuel gas at the outlet of the central nozzle per second is 0.001 to 1.2 kgH2m / s 2 ] range, b) The additional gas is oxygen or a gas containing more than 80% by weight of oxygen and has a gas content of 0.01 to 10.4 [kgO2m / s 2 ] per second at the exit of the concentric gas nozzle, c) Ratio of heating burner power to hydrogen gas kinetic power The ratio of the heating burner power WCHEM to the kinetic energy WKIN of the hydrogen gas [W] is in the range of WRATIO = 100.000 to 4.000.000 [1]. How to burn hydrogen gas.

[0210] 2. Hydrogen fuel gas (hydrogen gas means any gas containing 80% or more by weight H2) is introduced into the cavity of the burner by at least one central gas nozzle with the simultaneous injection of two independent flows of additional gas such that the fuel gas is surrounded by a concentric flow of primary additional gas, and the primary additional gas is surrounded by a concentric flow of secondary additional gas, e.g. a) The momentum of the hydrogen fuel gas at the outlet of the central nozzle and the outlet of the primary additional gas is 0.001 to 1.2 kgH2m / s 2 ] range, b) The secondary additional gas is oxygen or a gas containing more than 80% by weight of oxygen and has a viscosity of 0.01 to 10.4 [kgO2m / s 2 ] in the range of the momentum per second at the outlet of the secondary additional gas, c) Ratio of heating burner power to kinetic energy of hydrogen gas 2. The method for burning hydrogen gas in an industrial furnace according to embodiment 1, wherein the ratio of the heating burner output WCHEM to the kinetic energy WKIN [W] of the hydrogen gas is in the range of WRATIO=100.000 to 4.000.000[1].

[0211] 3. A method for burning hydrogen gas according to embodiments 1 and 2, in which the reaction mixture of hydrogen and oxygen is led into the furnace through a cavity provided in the ceramic part, in particular through a cavity provided in the ceramic wall of the furnace, the cavity having a cross-sectional shape of a circular, elliptical slot or a rectangular flat slot.

[0212] 4. A method for burning hydrogen gas according to embodiments 1, 2 and 3, in which the reaction mixture of hydrogen and oxygen is led into the furnace through a cavity having a ratio between the circumference of the burner and the circumference of the cavity cross section in the range of 0.95 to 1.05.

[0213] 5. A reaction mixture of hydrogen and oxygen is a) in the case of a burner and a cavity having a cylindrical shape, the ratio between the diameter of the burner outer part 2 and the length L1 of the cavity is in the ratio 2 to 6; b) For burners and cavities having the shape of either an elliptical slot or a rectangular flat slot, the ratio between the major axis of the slot cross section and the length L1 of the cavity is in the range of 1 to 4. The method for burning hydrogen gas according to any one of the preceding claims, wherein the hydrogen gas is introduced into a furnace through a cavity.

[0214] 6. Hydrogen fuel gas is introduced into the ceramic component through a central nozzle at a velocity (VH2) in the range of 5-85 m / s, while a primary additional gas is initially introduced into the burner in a controllable volume in the range of 90-110% by weight required for stoichiometric combustion of the fuel gas, the value of which velocity (VO2) satisfies the following relationship: VH2:vO2=1:(0.3~1.8) The method for burning hydrogen gas according to embodiments 1, 3, 4, 5 and 6, provided by:

[0215] 7. The flow cross-sectional area of ​​the central nozzle for hydrogen fuel gas given by the area of ​​the central nozzle and the flow cross-sectional area of ​​the additional gas are in the following relationship:

number

[0216] 8. Hydrogen gas is introduced into the ceramic part through a central nozzle at a velocity (vH2) of 5-85 m / s, the primary additional gas is hydrogen passing through an opening provided in the ceramic part, while the secondary additional gas is oxygen, the value of its injection velocity (vO2) into the ceramic part in a controllable capacity for stoichiometric combustion of the fuel gas being in accordance with the following relationship: VH2:vO2=1:(0.3~1.8) The method for burning hydrogen gas according to embodiments 1, 2, 3, 4, 5 and 6, as provided by:

[0217] 9. The flow cross-sectional area of ​​the central nozzle for hydrogen fuel gas and the cross-sectional area of ​​the primary additional gas is the sum of areas 1M and 2C:

number

number

[0218] 10. The method for burning hydrogen gas according to any one of the preceding embodiments, wherein the cavity in the opening cross section of the burner nozzle 3, 4, 9 and the ceramic component 10 has the shape of either a circle, a flat rectangular slot or an elliptical slot.

[0219] 11. The method of burning hydrogen gas according to any one of the preceding claims, wherein one or more additional injectors passing through the ceramic component allow for the introduction of additional gas, preferably an oxygen-containing gas containing more than 20% oxygen by weight, to separate the water vapor-rich zone of the hydrogen flame from the molten material in the furnace.

[0220] 12. The method for burning hydrogen gas according to any one of the preceding embodiments, wherein the amount and rate of the input fuel gas, the primary additional gas, the secondary additional gas and the additional gas, preferably an oxygen-containing gas containing more than 20% by weight of oxygen, can be continuously controlled to separate the water vapor-rich zone of the hydrogen flame from the molten material in the furnace.

[0221] 13. The method of combustion of hydrogen gas according to embodiments 1 to 12, wherein the amount and velocity of the input fuel gas, primary additional gas, secondary additional gas and additional gas, preferably oxygen-containing gas containing more than 20% by weight of oxygen, are controlled to separate the water vapor-rich zone of the hydrogen flame from the molten material in the furnace, and are optimized based on operational data, batch imaging and multispectral camera measurements by the control system of the glass melting furnace or industrial kiln.

[0222] 14. The method for burning hydrogen gas according to any one of the preceding claims, wherein the fuel gas is pure hydrogen or hydrogen in a mixture with other hydrocarbons and gases as additional gas, and the additional gas is oxygen, air or another oxidant containing more than 80% by weight of oxygen.

Claims

1. 1. A method of burning hydrogen gas in an industrial furnace, in particular a glass furnace or a metal melting furnace, by means of a multi-nozzle burner with controllable flow of said hydrogen fuel gas composition and said additional gas composition through a cavity into said industrial furnace to form a reaction mixture of said hydrogen fuel gas composition and said additional gas composition for burning in said industrial furnace, in particular a glass furnace or a metal melting furnace, comprising: - introducing said hydrogen fuel gas composition into said cavity from said multi-nozzle burner by a central flow of gas from at least one central gas nozzle with simultaneous injection of at least one independent further flow of said additional gas composition from at least one concentric gas nozzle; - said central flow of gas of said hydrogen fuel gas composition is surrounded by a concentric flow of gas of at least a primary additional gas composition, in particular said concentric flow of gas of said primary additional gas composition being a peripheral concentric flow of gas; the hydrogen fuel gas composition is formed by a first fuel gas component of at least 80% by weight of hydrogen gas and at most 20% by weight of another fuel gas or gas component other than hydrogen gas; said additional gas composition is formed by an oxygen-containing first oxidant gas component having an oxygen content of 80% by weight or more of oxygen gas; a1) the gas momentum per second of the central stream of the hydrogen fuel gas composition at the outlet of the central gas nozzle is between 0.001 and 1.2 [kgH2m / s ２ ] in the range b1) the gas momentum per second of the concentric flow of the primary additional gas composition at the outlet of the concentric gas nozzle is between 0.01 and 10.4 [kgO2 m / s ２ ] in the range c) The ratio of the heating burner power (WCHEM [W]) to the kinetic power of the hydrogen fuel gas composition (WKIN [W]) is in the range of WRATIO = 100.000 to 4.000.000 [1] A method comprising:

2. introducing said hydrogen fuel gas composition into said cavity of said multi-nozzle burner through said at least one central gas nozzle with simultaneous injection of at least first and second independent further flows of said additional gas composition; - said central flow of gas of said hydrogen fuel gas composition is surrounded by said concentric flow of gas of said primary additional gas composition; the concentric flow of gases of the primary additional gas composition surrounds a concentric flow of gases of a secondary additional gas composition, the secondary additional gas composition being between the central flow of gases of the hydrogen fuel gas composition and the concentric flow of gases of the primary additional gas composition, in particular the concentric flow of gases of the primary additional gas composition being a peripheral concentric flow of gases, The method of claim 1.

3. b2) the gas momentum per second of the concentric flow of the primary and / or secondary additional gas composition at the outlet of the concentric gas nozzle is between 0.01 and 10.4 [kgO2 m / s ２ 3. The method of claim 2, wherein the range is

4. The hydrogen fuel gas composition is introduced into the cavity of the multi-nozzle burner. - introducing a central flow of gas of said hydrogen fuel gas composition from said at least one central gas nozzle and a concentric flow of gas of said hydrogen fuel gas composition from at least one further concentric gas nozzle with simultaneous input of at least one independent further flow of at least one further gas composition from at least one concentric gas nozzle; - the central flow of gas of the hydrogen fuel gas composition is surrounded by the concentric flows of gas of the hydrogen fuel gas composition; the concentric flow of gas of the hydrogen fuel gas composition is surrounded by the concentric flow of the primary and / or secondary additional gas composition, in particular the concentric flow of the primary or secondary additional gas composition is a peripheral concentric flow of gas, The method of claim 1.

5. a2) the gas momentum per second of the concentric flow of the further hydrogen fuel gas composition at the outlet of the concentric gas nozzle is between 0.001 and 1.2 [kgH2m / s ２ 5. The method of claim 4, wherein the range is

6. 6. The method according to claim 1 , further comprising directing the reaction mixture of the hydrogen fuel gas composition and the additional gas composition into the furnace through a cavity in a ceramic part, in particular through a cavity in a ceramic wall of the furnace.

7. 7. The method according to any one or more of claims 1 to 6, wherein the reaction mixture of the hydrogen fuel gas composition and the additional gas composition is conducted into the furnace through the cavity, and the ratio between the circumference of a cross section of the burner and the circumference of a cross section of the cavity is in the range of 0.95 to 1.0 or 1.0 to 1.

05.

8. 8. The method according to claim 1, wherein the cavity has a cross-sectional shape in the shape of a circular or elliptical or rectangular flat slot.

9. directing the reaction mixture of the hydrogen fuel gas composition and the additional gas composition through the cavity into the furnace; a) the cavity has a circular cross-sectional shape such that the cavity has the shape of a cylinder with an axial length and a circular bottom area, the ratio between the diameter of the bottom area, in particular the burner outer part, and the axial length of the cylinder being in the range of 2 to 6; b) the cavity has an elliptical or rectangular cross-sectional shape such that the cavity has an axial length and an elliptical or rectangular slot shape of an elliptical or rectangular base region, and the ratio between the major axis of the elliptical or rectangular base region and the axial length of the elliptical or rectangular slot is in the range of 1 to 4; 9. A method according to any one or more of claims 1 to 8.

10. 10. The method of any one or more of claims 1 to 9, wherein the hydrogen fuel gas composition is introduced into the cavity through at least the central gas nozzle, and at the outlet of the central gas nozzle, the central flow of gases of the hydrogen fuel gas composition has a velocity in the range of 5 to 85 m / s.

11. 11. The method of any one or more of claims 1 to 10, wherein the primary additional gas composition is introduced into the burner in a rate controllable volume in the range of 90 to 110% by weight required for stoichiometric combustion of the hydrogen fuel gas composition.

12. The velocity of the central flow of gas of the hydrogen fuel gas composition relative to the concentric flow of gas of the primary additional gas composition is in accordance with the following relationship: VH2:vO2=1:(0.3-1.8) 12. The method of claim 1 , wherein the method is given by:

13. a cross-sectional flow area of ​​the hydrogen fuel gas composition is given by the opening area of ​​the central gas nozzle, optionally given by the opening area of ​​the central gas nozzle plus the opening areas of the further concentric gas nozzles; a cross-sectional flow area of ​​the additional gas composition is given by the opening area of ​​the at least one concentric gas nozzle, optionally given by the opening area of ​​the at least one concentric gas nozzle plus the opening areas of the further concentric gas nozzles for primary and secondary additional gas compositions; The cross-sectional flow area of ​​the hydrogen fuel gas composition and the cross-sectional flow area of ​​the additional gas composition have the following relationship: [0010] Located in 13. A method according to any one or more of the preceding claims.

14. A method according to any one or more of claims 1 to 13, characterized in that the hydrogen fuel gas composition is introduced into the cavity through at least the concentric gas nozzle, and at the outlet of the concentric gas nozzle, the concentric flows of gases of the hydrogen fuel gas composition have a velocity in the range of 5 to 85 m / s.

15. 15. The method of any one or more of claims 1 to 14, wherein the secondary additional gas composition is introduced to the burner in a rate controllable volume in the range of 90 to 110% by weight required for stoichiometric combustion of the hydrogen fuel gas composition.

16. The value of the concentric flow of gas of the hydrogen fuel gas composition relative to the velocity of the concentric flow of gas of the primary and / or secondary additional gas composition is in accordance with the following relationship: VH2:vO2=1:(0.3-1.8) 16. The method of claim 1 , wherein the method is given by:

17. a cross-sectional flow area of ​​the hydrogen fuel gas composition is determined by the opening area of ​​the central gas nozzle; [0025] and optionally the opening area of ​​the central gas nozzle plus the opening area of ​​the further concentric gas nozzle is given by: [0030] and the flow cross-sectional area of ​​the further concentric gas nozzle relative to the concentric gas nozzle area of ​​the secondary additional gas region is given by the following relationship: [0045] 17. The method according to any one or more of claims 1 to 16, wherein

18. for each multi-nozzle burner, at least one injector is provided which passes through the ceramic part; - introducing an additional gas flow, preferably an additional gas flow of oxygen or an additional gas flow containing a purge gas containing more than 20% by weight of oxygen, into the industrial furnace by means of said injector, - separating the water vapor-rich zone of the hydrogen flame of the reaction mixture from the molten material in the furnace by introducing said additional gas flow; 18. A method according to any one or more of the preceding claims.

19. 19. A method according to any one or more of the preceding claims, wherein the amounts and rates of the input hydrogen fuel gas composition and additional gas composition and additional gas flows are controlled, in particular continuously controlled.

20. 20. The method of claim 19, wherein the control is based on operational data, batch imaging and / or multispectral camera measurements by the control system of the glass melting furnace or industrial kiln and is specifically adapted to optimize the input hydrogen fuel gas composition and additional gas compositions and the amounts and velocities of additional gas flows.

21. - the hydrogen fuel gas composition is formed solely from hydrogen gas as the sole fuel gas component, or the hydrogen fuel gas composition is formed from hydrogen gas in a mixture with another fuel gas of a hydrocarbon and other gases; and / or the additional gas composition is formed solely from oxygen gas as the only oxidant gas component, or the additional gas composition is formed from air or another oxidant gas having an oxygen content of 80% or more by weight; 21. A method according to any one or more of the preceding claims.

22. A multi-nozzle burner for burning hydrogen gas in an industrial furnace, in particular a glass furnace or a metal melting furnace, said multi-nozzle burner being adapted for a controllable flow of a hydrogen fuel gas composition and an additional gas composition through a cavity into said industrial furnace to form a reaction mixture of said hydrogen fuel gas composition and an additional gas composition for burning in said industrial furnace, said hydrogen fuel gas composition being introduced into said cavity from said multi-nozzle burner by a central flow of gas from at least one central gas nozzle of said multi-nozzle burner with simultaneous introduction of at least one independent further flow of said additional gas composition from at least one concentric gas nozzle of said multi-nozzle burner, the central flow of gas of the hydrogen fuel gas composition is surrounded by a concentric flow of gas of at least a primary additional gas composition, in particular the concentric flow of gas of the primary additional gas composition is a peripheral concentric flow of gas, In the multi-nozzle burner, The multi-nozzle burner is further adapted to carry out the method according to any one of claims 1 to 21. Multi-nozzle burner.

23. said multi-nozzle burner comprises an injection tube body with a central tube (M) with a central opening (1M) and peripheral concentric tubes (CP) with peripheral openings (3P), said injection tube body (501) being fixed with an outlet to a ceramic component (10), said peripheral concentric tubes (CP) and said central tube comprising said at least one central gas nozzle (1) and said at least one concentric gas nozzle (3), in particular said central gas nozzle (1) being surrounded by said concentric gas nozzles (3) at an outer periphery forming the outer body of said injection tube body (501), optionally said concentric gas nozzles (3) surrounding further concentric gas nozzles (2) at an outer periphery forming the outer body of said injection tube body, 23. A multi-nozzle burner according to claim 22.

24. 24. A multi-nozzle burner according to claim 22 or 23, wherein the tips of the central gas nozzle (1), the concentric gas nozzle (3) and optionally the further concentric gas nozzle (2) are arranged at the same distance within the cavity.

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