TWI416051B - Through-port oxy-fuel burner - Google Patents

Abstract

A fluid-cooled through-port oxy-fuel burner for converting an air-fuel regenerator port from air-fuel combustion to oxy-fuel combustion and an associated furnace and method. The oxy-fuel burner is suitable for installing through a regenerator port neck. The burner has an elbow-like bend to accommodate the geometry of the regenerator port neck. The burner has a cooling fluid jacket, a fuel conduit, a first oxidant conduit, and optionally an oxidant staging conduit.

Description

Wear oxygen-fuel burner

The present invention relates to an oxy-fuel burner for use in a high temperature furnace (for example, a glass kiln).

Regenerative glass kiln ignited by air fuel is well known. The regenerative glass kiln has multiple air fuel accumulators for generating a combustion flame for glass melting. Various references refer to the basic design features of glass kiln, for example, by Wolfgang Trier, translated by KL Loewenstein, "Glass Furnaces, Design Construction and Operation", Society of Glass Technology, Snow, UK, 2000 And "The Handbook of Glass Manufacture", edited by Fay Tooley, 3rd Edition, Volumes 1 and 2, Ashlee Publishing Company, New York, 1984, incorporated herein by reference.

The conversion of one or more regenerator crucibles to oxy-fuel ignition may require that the furnace be refurbished into a mixing furnace, such as that described in U.S. Patent No. 6,519,973, the disclosure of which is incorporated herein by reference.

Terminating air fuel ignition and replacing energy input with oxygen-fuel ignition is challenging. Because the furnace was originally designed as an air fuel furnace, it was difficult to find a suitable location for the installation of an oxy-fuel burner. There is a position on the neck of the regenerator that has been used to set up the oxy-fuel burner.

The back of the crucible can be blocked or obstructed to limit or prevent hot air from flowing from the accumulator into the crucible. A hole can be made in the top, bottom or side of the neck for the oxy-fuel burner. The oxy-fuel burner is then passed through the hole and inserted into the neck. The oxy-fuel burner must be designed to inject fuel and oxygen into the combustion space of the furnace. This requires the burner to have an elbow or elbow to change the direction of flow of the fuel and oxidant. A problem with establishing a burner through the neck is that the hole size for inserting the burner is small in order to maintain the structural integrity of the neck.

When the burner is set up through a hole in the top or bottom of the neck of the heat accumulator, the burner will have a substantially vertical section through which the fuel and oxygen are delivered and inject the fuel and oxygen into the burner. A generally horizontal section of the combustion space of the glass kiln, and an elbow section between the generally vertical section and the generally horizontal section. When the burner is set up through the sidewall of the regenerator jaw neck, the burner can have two generally horizontal sections and an elbow section between the two substantially horizontal sections.

A problem associated with the establishment of an oxy-fuel burner in the neck of the regenerator is that the oxy-fuel burner must bring the injection nozzle close to the elbow section, which must be rushed or significantly changed near the injection nozzle. Flow direction. Due to the space limitations in the regenerator crucible, it is problematic that the long horizontal section forms an end in the injection nozzle in the crucible. Furthermore, the problem of the long horizontal section forming the end in the injection nozzle is because a large hole must be cut in the wall of the crucible, which may impact the structural steel surrounding the crucible. A sharp or significant change in the direction of flow near the injection nozzle causes a high pressure drop and disturbs the flow leaving the nozzle. The disturbance causes rapid mixing and subsequent combustion close to the nozzle, resulting in a short flame. Because of the overheating of the nozzle, the relationship of overheating of the refractory material in the neck of the crucible when the burner is used as a through-burner does not want to approach the combustion of the nozzle.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a burner suitable for utilizing a heat accumulator to ignite an air fuel to oxy-fuel ignition while solving the aforementioned problems. The invention also relates to a furnace having the burner and a method of heating the furnace using the burner. This method can be used during regenerator repair to extend the life of the furnace and/or increase the production rate of existing furnaces.

The combustor includes a first cooling fluid jacket having an outer equivalent diameter, D, a first oxidant conduit disposed in a fixed spaced relationship with the first cooling fluid jacket and disposed substantially concentrically therein, and a fuel conduit.

The first oxidant conduit has an inlet, a first portion downstream of the inlet of the first oxidant conduit, a curved portion downstream of the first portion of the first oxidant conduit, and a second portion downstream of the curved portion of the first oxidant conduit Part.

The curved portion has an angle of 45° to 120°, α, the angle, α, which may be 60° to 110°.

The second portion of the first oxidant conduit forms a tip at the outlet end and has a flow axis and length, L. The second portion can have a circular cross section.

The fuel conduit has an inlet, a first portion and a second portion downstream of the inlet. The first portion of the fuel conduit is in fixed spaced relationship with the first portion of the first oxidant conduit and is disposed substantially concentrically therein. The curved portion of the fuel conduit is in a fixed spaced relationship with the curved portion of the oxidant conduit and is disposed substantially concentrically therein. The second of the fuel conduit The portion forms an end at the outlet end and has a flow axis. The second portion of the fuel conduit is in fixed spaced relationship with the second portion of the first oxidant conduit and is disposed substantially concentrically therein. The second portion of the fuel conduit can have a circular cross section.

The flow axis of the second portion of the first oxidant conduit can be straight and can be substantially parallel or substantially coincident with the flow axis of the second portion of the fuel conduit.

An oxidant passage is formed or defined between the second portion of the fuel conduit and the second portion of the first oxidant conduit. The oxidant passage has an inlet section, a transition section downstream of the inlet section, and an outlet section downstream of the transition section. The inlet section has a cross-sectional area, A _i , which has a cross-sectional area, A _o .

Between 0.8 and 7 or between 1.4 and 7, and Between 1.3 and 5. The second portion of the first oxidant conduit can have a convex inner surface in the transition of the oxidant passage.

The second portion of the fuel conduit defines a fuel passage, wherein the fuel passage has an inlet section, a transition section downstream of the inlet section, and an outlet section downstream of the transition section. An inlet section of the second portion of the fuel conduit has a cross-sectional area, A _fi , and an outlet section of the second portion of the fuel conduit has a cross-sectional area, A _fo , wherein It can range from 1.0 to 5 or between 1.37 and 5.

The second portion of the fuel conduit may have a concave outer surface at the transition of the oxidant passage.

The second portion of the fuel conduit can have a concave inner surface and a convex inner surface in the transition of the fuel passage, wherein the convex inner surface of the fuel conduit is downstream of the concave inner surface of the fuel conduit.

The outlet end of the second portion of the first oxidant conduit projects from the second portion of the fuel conduit by 0.2 cm to 3 cm.

The combustor can additionally include a second oxidant conduit in fixed spaced relationship with the second portion of the first oxidant conduit.

The second oxidant conduit can be disposed in a fixed spaced relationship with the first cooling fluid jacket and disposed substantially concentrically therein. The combustor can additionally include a second cooling fluid jacket, and the second oxidant conduit can be disposed in a fixed spaced relationship with the second cooling fluid jacket and disposed substantially concentrically therein. The second oxidant conduit may have an inlet, a first portion downstream of the inlet of the second oxidant conduit, a curved portion downstream of the first portion of the second oxidant conduit, and a second portion downstream of the curved portion of the second oxidant conduit Two parts.

The curved portion of the second oxidant conduit has an angle β, the angle β is within 15° of the angle α, and the second portion downstream of the curved portion of the second oxidant conduit, the second oxidant conduit The second portion forms a tip in the nozzle and has a flow axis, and the second portion of the second oxidant conduit is in fixed spaced relationship with the second portion of the first oxidant conduit.

The angle, β may be within 2° of the angle, α, and the flow axis of the second portion of the second oxidant conduit may be substantially parallel to the flow axis of the second portion of the first oxidant conduit.

The nozzle has an inlet and an outlet. The outlet end of the second portion of the first oxidant conduit may protrude from the nozzle outlet of the second portion of the second oxidant conduit by 0.2 cm to 3 cm. The inlet may have a circular cross section and a cross-sectional area, A _ni , and the outlet has a non-circular cross section and a cross-sectional area, A _no , wherein the outlet of the nozzle has an aspect ratio of 1.5 to 5. Can be between 1.25 and 5.

The nozzle of the second oxidant conduit can have a convergence height and a divergence width.

The nozzle of the second oxidant conduit has a concave surface transition between a circular cross section and a non-circular cross section.

The furnace includes a heat accumulator, a furnace combustion chamber, and a regenerator crucible that connects the regenerator to the combustion chamber of the furnace, the regenerator neck defining a weir and a weir opening in the wall of the furnace. The furnace also includes a burner of the character described above. The burner passes through the regenerator jaw neck and into the crucible, and the burner is configured to direct fuel and oxidant through the crucible opening and into the furnace.

The furnace also includes a melting tank basin disposed below the combustion chamber of the furnace and adjacent to the combustion chamber of the furnace, a glass forming component introduced into the filling end of the melting tank, and a discharge of the glass product from the molten tank end. The furnace also contains an exhaust gas enthalpy in one of the walls of the furnace for extracting combustion products from the combustion chamber of the furnace.

In a specific embodiment, the second oxidant conduit passes through the wall of the furnace below the opening of the crucible and is configured to direct oxidant into the furnace.

The method of heating a furnace includes: blocking air flow to the crucible, terminating the combustion flow to an air fuel burner associated with the crucible, establishing the burner such that the burner passes through the regenerator to the neck and enters the使 passing the coolant through the first cooling fluid jacket and, if present, through the second cooling fluid jacket, introducing the first oxidant gas into the furnace through the first oxidant conduit, and passing the fuel through the fuel conduit or Another fuel is introduced into the furnace, the fuel or another fuel is combusted with the first oxidant gas to form a combustion product, and the combustion products are withdrawn from the furnace combustion chamber through an exhaust pipe.

The method can include continuously flowing air through the crucible at a stoichiometric amount of air required to combust the fuel through the burner in an amount greater than 5% to less than or equal to 25%.

The method can additionally include introducing the first oxidant gas or the second oxidant gas into the furnace through a second oxidant conduit to combust the fuel or another fuel.

The article "a" or "an", when used in the specification and the claims of the claims. The use of "a" does not limit the meaning of a single feature unless explicitly stated. The article "the" preceding a singular or plural noun or a noun phrase means a specified feature and may have a singular or plural meaning depending on the context to which it applies. The adjective "any" means one, some or all of the number that does not distinguish anything.

The phrase "at least a portion" means "some or all".

Detailed descriptions of well-known devices, circuits, and methods are omitted in order to avoid obscuring the description and unnecessary details of the present invention.

The present invention relates to a burner. More specifically, the present invention relates to an oxy-fuel burner ignited by an oxy-fuel igniting alternative to an air fuel in a glass kiln having an air fuel regenerator crucible. The burner is particularly suitable for at least partially converting a regenerator crucible from air fuel ignition to oxy-fuel ignition. Due to the geometry of the glass kiln regenerator crucible, the burner used for this conversion requires a sharp or significant change in flow direction near the injection nozzle.

In the event that the associated regenerator must be repaired, the regenerator 埠 can be temporarily switched from ignited by air fuel to oxy-fuel ignited. The regenerator crucible can be converted to a more permanent basis for the benefit of oxy-fuel ignition to achieve oxy-fuel benefits. Several of the crucibles closest to the end of the batch of the glass kiln can be converted to oxy-fuel ignition to improve batch melting by the oxy-fuel flames.

Referring now to the drawings in which like reference numerals refer to the like in the drawings, FIG. 1 shows a burner 1 in accordance with a particular embodiment of the invention, and FIG. 2 shows a section of a furnace 100 that includes heat storage. The neck portion 105 and the burner 101 are disposed in the neck of the heat accumulator.

The burners 1 and 101 include a first cooling fluid jacket 10, a first oxidant conduit 20, and a fuel conduit 40. The first cooling fluid jacket 10 has an outer equivalent diameter, D, which is equal to the outer diameter in the case of a circular cross section and equal to 2 times the outer cross-sectional area of the outer casing in terms of a non-circular cross section. The first oxidant conduit 20 is disposed in a fixed spaced relationship with the first cooling fluid jacket 10 and disposed substantially concentrically therein, and the fuel conduit 40 is in a fixed spaced relationship with the first oxidant conduit 20 and is disposed substantially concentrically Within it. Substantially concentric means that the axis of one catheter is common or slightly displaced by at most 2 cm from the axis of the other catheter.

The cooling fluid jacket is an outer envelope or sleeve, such as an envelope enclosing the intermediate space through which temperature control fluid can circulate. The flow cooling fluid can be water. Cooling fluid jackets (e.g., water-cooled jackets) are well known in the art of burners and combustion. The details of the design of the cooling fluid jacket are not critical to the invention. Those skilled in the art can readily select and/or modify suitable cooling fluid jacket designs from those well known in the art.

The first cooling fluid jacket 10 must prevent the burner from overheating. When the burner is inserted into a glass kiln heat accumulator, heat from the furnace will radiate to the outer surface of the burner. When the burner is running, the flame from the burner will radiate back to the burner. Water or other cooling fluid is introduced into the inlet 11 of the first cooling fluid jacket 10 and flows around the first oxidant conduit 20, including the region around the fuel and oxidant discharge ends. The water or other cooling fluid is withdrawn from the outlet 13 of the first cooling fluid jacket 10.

As used herein, a conduit is any device used to transport fluids, for example, a delivery tube, tubule or tube, and the like. The first cooling fluid jacket 10, the first oxidant conduit 20, and the fuel conduit 40 are made of metal, preferably stainless steel. Those skilled in the art can readily select materials suitable for use in constructing the burner.

The oxidant conduit is a conduit that is intended to deliver oxidant gas and to a source of oxidant supply. The oxidant gas is any gas containing more than 21% by volume of oxygen. Industrial grade oxygen having an oxygen concentration of 80% by volume to 100% by volume is an oxidant gas, and since it is a gaseous exhaust stream from a nitrogen device, it often has an oxygen concentration of 60% by volume to 80% by volume. The oxidant may also be a mixture of air and oxygen having an oxygen concentration of between 22% and 28% by volume or between 28% and 60% by volume of the industrial or effluent stream. The oxidant conduit can be designed to utilize industrial grade oxygen compatible materials to deliver industrial grade oxygen.

The fuel conduit is a conduit that is intended to deliver fuel. Connect the fuel conduit to the fuel supply. The fuel can be a gaseous fuel, for example, natural gas, propane or other gaseous hydrocarbons, hydrogen, carbon monoxide, or a combination thereof. Or the fuel may be a liquid, for example, No. 1 distillate, No. 2 distillate fuel oil, diesel fuel, biodiesel and its by-products (such as glycerin), kerosene, No. 4 fuel oil, No. 5 residual oil, Residual fuel oil No. 6, fuel depot - Type C fuel oil and others commonly known to those skilled in the art. The liquid fuel can be atomized by any of a number of devices conventionally known to those skilled in the art.

The first oxidant conduit 20 has an inlet 21 for receiving oxidant gas, a first portion 23 downstream of the inlet 21, a curved portion 25 downstream of the first portion 23, and a second portion 27 downstream of the curved portion 25. . The oxidant gas can be industrial grade oxygen.

The upstream and downstream are defined relative to the expected fluid flow, for example, the fuel or oxidant. The upstream end corresponds to the end closest to the inlet where fluid is introduced into the apparatus and the downstream end is correspondingly closest to the outlet or nozzle end where the fluid exits the apparatus.

The inlet 21 can include a quick disconnect accessory or other accessory suitable for inspecting the supply of oxidant gas to the burner.

The first portion 23 can have a circular cross section. The first portion 23 can also have a spacer to ensure concentric properties between the first portion of the first oxidant conduit and the first portion of the fuel conduit.

The curved portion 25 has an angle of 45 to 120, α. The angle, α, can be from 60° to 110°. This angle is defined as the compensation angle of the angle. The angle, which is less than 180°, is the angle defined between the straight segment defined by the first portion of the catheter and the straight segment of the second portion of the catheter. The angle with respect to the first oxidant conduit is an angle defined between a straight segment defined by the first portion of the first oxidant conduit and a straight segment of the second portion of the first oxidant conduit. The angle shown in Figs. 1 and 2, α, is the compensation angle with respect to the angle of the first oxidant conduit. A bend of 0° is equivalent to no bending, that is, straight. A 180° bend angle is equivalent to a “U-shaped” bend.

The bend in the curved portion 25 can be smooth, having a radius as shown in FIG. 2, or as shown in FIG. 1, which can have an acute angle.

The second portion 27 of the first oxidant conduit 20 forms an end at the outlet end 29 and has a flow axis 22 and length, L. The second portion 27 can have a circular cross section.

The flow axis corresponds to a line passing through the direction of flow through the center of the geometry of the section of the conduit, wherein the sections are in a plane perpendicular to the line. The flow axis can include a curve. With regard to this burner, at least one section of the flow shaft is a straight section.

For the purposes of this disclosure, the length of the second portion of the first oxidant conduit, L, corresponds to a straight line segment of the flow axis between the curved portion and the outlet end shown in Figures 1 and 2 .

The fuel conduit 40 has an inlet 41 for receiving fuel, a first portion 43 downstream of the inlet 41, a curved portion 45, and a second portion 47.

The inlet 41 can include a quick disconnect accessory or other accessory suitable for inspecting the supply of oxidant gas to the burner.

As shown in FIGS. 1 and 2, the first portion 43 of the fuel conduit 40 is disposed in a fixed spaced relationship with the first portion 23 of the first oxidant conduit 20 and is disposed substantially concentrically therein. The curved portion 45 is disposed in a fixed spaced relationship with the curved portion 25 and is disposed substantially concentrically therein.

The bend in the curved portion 45 can be smooth, having a radius as shown in Figure 2, or having an acute angle as shown in Figure 1. The curved portion 45 is compatible with the curved portion 25.

The second portion 27 of the first oxidant conduit 20 forms an end at the outlet end 29 and has a flow axis 22 and length, L. The second portion 27 can have a circular cross section.

The second portion 47 forms an end at the outlet end 49 and has a flow axis 42. The second portion 47 is disposed in a fixed spaced relationship with the second portion 27 of the first oxidant conduit 20 and is disposed substantially concentrically therein. The second portion 47 can have a circular cross section.

The second portion 47 of the fuel conduit can be concentric with the second portion 27 of the first oxidant conduit 20 such that both the flow shaft 42 and the flow shaft 22 are straight and substantially parallel or substantially coincident. The flow shaft 42 and the flow shaft 22 are coincident in FIG.

The phrase "parallel" means extending in the same direction, wherever equal distances are met and not met. With respect to the flow axis 22 and the flow axis 42, substantially parallel means a maximum separation distance deviation of 2 cm.

The phrase "coincident" means occupying the same space or location. With respect to the flow shaft 22 and the flow shaft 42, substantially overlapping means superposition within a range of 2 cm.

An oxidant passage 50 is formed or defined between the second portion 47 of the fuel conduit 40 and the second portion 27 of the first oxidant conduit 20. The oxidant passage 50 has an inlet section 51, a transition section 53 downstream of the inlet section 51 and an outlet section 55 downstream of the transition section 53. The inlet section 51 has a cross-sectional area, A _i , which has a cross-sectional area, A _o . The cross-sectional area, A _{o , is} designed to provide an oxidant gas velocity of from about 30 m/sec to about 150 m/s when designing the oxidant gas flow rate.

The sharp or significant change in the flow direction of the first oxidant near the injection nozzle can be described by the relationship between the length of the first cooling fluid jacket, L, and the outer equivalent diameter, D. It is desirable for us to maximize the ratio L/D to minimize non-uniformity in the first oxidant velocity profile at the injection nozzle because velocity non-uniformity is the primary cause of accelerated fuel near the injection nozzle, which may This causes excessive flame temperatures and, as a result, the burner is damaged or malfunctions. However, a short length is required in the limited space that can be achieved in order to fit the burner assembly into the regenerator crucible of the glass kiln. It is estimated that the maximum allowable L/D based on the available space is 7.0.

One solution to achieve an acceptable flow distribution with a short L/D is to place the static mixing device in the second portion of the first oxidant passage. Static mixing devices are static obstructions placed in the flow field that can contribute to flow redistribution by substantially increasing the turbulent mixing and diffusion, substantially through the dissipation of static pressure. A common example of a static mixing device is a perforated plate; that is, a plate that crosses the flow section, the plate containing a plurality of small holes that traverse the plate, and the flow must pass through the plate.

Unfortunately, both the dissipation of static pressure and the generation of turbulent mixing/diffusion are undesired flow characteristics in this case. First, increasing the turbulence of the oxidant stream results in a more rapid mixing between the oxidant and the fuel, which causes problems with excessive flame temperatures near the burner nozzle to deteriorate. Second, the dissipation of static pressure results in a higher supply pressure requirement for the oxidant. In some cases, this higher supply pressure requirement may not be met, but in other cases it was established because of the need to set up and operate one or more gas compressors to add considerable capital and operating costs. With regard to a particular embodiment of the combustor, the combustor includes a second oxidant conduit in fixed spaced relationship with the first oxidant conduit: . Specific embodiments of a burner that does not include the second oxidant conduit: .

It is preferred to uniformly distribute and straighten the flow of the oxidant, and prevent the oxidant from prematurely mixing with the fuel in the furnace without the characteristics of the aforementioned undesirable static mixing device. The characteristics of the burner are reduced from the inlet section. The cross-sectional area of the oxidant passage 50 from 51 to the outlet section 55. This reduction in the cross-sectional area of the first oxidant passage is achieved through the transition section 53. In order to improve the first oxidant flow distribution, we want to maximize the ratio of inlet to outlet cross-sectional area. However, for a specific first oxidant speed at the outlet, increase the ratio It is necessary to increase the size of the inlet cross-sectional area. Due to the limited space available in the regenerator, the actual limit for the value above this ratio is . About this burner, .

As shown enlarged in Figures 1, 2 and 3, the second portion 27 of the oxidant conduit 20 can have a convex inner surface in the transition section 53 of the oxidant passage 50.

As shown enlarged in Figures 1, 2 and 3, the second portion 47 of the fuel conduit 40 can have a concave outer surface in the transition section 53 of the oxidant passage 50. These convex and concave curvatures help to straighten the flow of the oxidant so that when it approaches the outlet end 29 it aligns with the axis 22 of the first oxidant stream while reducing the generation and diffusion of the turbulence.

The second portion 47 of the fuel conduit 40 forms or defines a fuel passage 60. The fuel passage 60 has an inlet section 61, a transition section 63 downstream of the inlet section 61, and an outlet section 65 downstream of the transition section 63. The inlet section of the second portion of the fuel conduit has a cross-sectional area, A _fi , and the outlet section of the second portion of the fuel conduit has a cross-sectional area, A _fo .

Similar to the second portion of the first oxidant conduit, tends to straighten the flow of the fuel, and the burner characteristic that prevents the oxidant from mixing with the acceleration of the fuel in the furnace is reduced from the inlet section 61 to The cross-sectional area of the fuel passage 60 of the outlet section 65. In order to improve the fuel flow distribution, we want to maximize the ratio of the inlet to outlet cross-sectional area. However, for the specific fuel speed at the exit, increase the ratio It is necessary to increase the size of the inlet cross-sectional area. Due to the limited space available in the regenerator, the actual limit for the value above this ratio is Equal to 5. About this burner, or . The cross-sectional area, A _fo , is designed to provide a fuel velocity of from about 25 m/s to about 150 m/s, depending on the desired ignition rate (i.e., fuel flow rate).

As shown in FIGS. 1 and 2, the second portion 47 of the fuel conduit 40 may have a concave inner surface and a convex inner surface in the transition portion of the fuel passage 60, wherein the convex inner surface is at the fuel Downstream of the concave inner surface of the conduit 60. This geometry helps to facilitate realignment of the flow at the inner surface of the fuel passage with the flow shaft 42 while minimizing disturbance vortex generation and diffusion in the fuel flow. By minimizing the flow of the first oxidant and fuel along their respective axes and simultaneously the generation and diffusion of the turbulence, these characteristics will reduce the rate of mixing as the fuel and oxidant are discharged into the furnace. As previously mentioned, this is important to prevent high temperature damage caused by short oxygen/fuel flames in the metal components of the burner.

As shown in FIGS. 1 and 2, the outlet end 29 of the second portion 27 of the oxidant conduit 20 projects from the outlet end 49 of the second portion 47 of the fuel conduit 40. The outlet end 29 can protrude from the outlet end 49 by 0.2 cm to 3 cm. Highlighting means protruding or extending outward from the surrounding surface or surrounding environment.

The outlet end 49 of the fuel conduit 40 is recessed from the outlet end 29 of the oxidant conduit 20 to prevent the outlet end 49 from being exposed to radiation from the burner and the high temperature environment of the glass kiln. The oxidant conduit 20 including the oxidant conduit outlet end 29 is cooled by circulation of a cooling fluid through the first cooling fluid jacket 10.

On the other hand, the fuel conduit 40 is cooled by the flow of oxidant through the oxidant passage. By recessing the outlet end 49, the outlet end 49 will be exposed to less heat radiation and overheating can be avoided. In the case where the outlet end 49 is too depressed, the fuel and oxidant may react within the combustor, causing damage to the combustor due to overheating of the oxidant conduit. An appropriate balance between shielding the outlet end 49 from thermal radiation and mixing the fuel and oxidant is provided by projecting the outlet end 29 from the outlet end 49 by 0.2 cm to 3 cm.

The burner can also include oxidant classification. Oxidant grading in the context of the present disclosure means that a portion of the combustion oxygen is retained from the first oxidant stream such that it can be delivered at a later "stage" of combustion of the fuel. As shown in Figure 1, the grading nozzle can be part of a burner placed in the regenerator crucible, a so-called spur nozzle, and/or as shown in Figure 2, the grading nozzle can be placed A separate section below the heat accumulator, the so-called underarm nozzle. It has been found that oxidant grading provides a means of adjusting the flame in the furnace.

The graded oxygen can lower the peak temperature of the oxygen/fuel flame. Reducing the peak temperature will reduce the risk of damage to the burner due to high temperatures and also reduce the rate of fuel and oxidant mixing. Reducing the fuel and oxidant mixing rate will slow the combustion process, thereby resulting in a longer flame, which is more desirable. Furthermore, the classification creates a fuel-rich or oxygen-poor combustion zone within the flame. The fuel-rich zone promotes the formation of carbon-rich solids (oily fumes) that promote radiant heat transfer from the flame to the glass melt and also result in lower NOx emissions. However, there is a practical limit to the degree of grading that can be used safely and effectively. This limit is often set by the momentum of the flame, which decreases the momentum of the flame as the fractionated oxygen increases. If the momentum of the flame is too low, the flame will become unstable in the furnace and may, for example, rise up toward the top of the furnace where it may damage the top refractory material.

The graded oxygen configuration and orientation also affects the flame from the burner. The graded oxidant introduced directly below the first oxidant/fuel nozzle has suitable characteristics. For example, the graded oxidant introduced at this location is mixed with fuel just downstream of the burner nozzle and is thus substantially not diluted by the flue gas. Furthermore, grading at this location effectively enhances the combustion of the portion of the main fuel burner below the flame. This causes the radiant energy from the flame to preferentially direct the glass melt downstream, rather than upward toward the top of the furnace. If the crucible is involved in overheating, the staged nozzle in the crucible may be directed downstream to the crucible where it provides convective cooling of the surface. Alternatively, if there is not enough space for the burner nozzle and the nozzle to be accommodated in the crucible at the same time, the graded oxygen nozzle can be placed elsewhere, for example, below the crucible but above the glass melt. surface.

The oxidant grading comprising both the underside of the regenerator and in the regenerator crucible imparts to the operator an effect on the heating of the glass melt, the overheating of the regenerator, the refractory, and the release of contaminant emissions (e.g., NOx). The experiment was carried out in a helium test furnace. The experimental results confirmed the substantial effect of the amount and position of the oxidant classification on heat transfer, temperature and roof temperature. For example, Figure 5 indicates that a much larger heat flux can be achieved at the bottom of the furnace by 80% of the sulphur sulphur grading ratio "no grading" and 80% of the underarm classification. While these data provide a representative trend, the optimal oxidizer grading amount and location is best determined by the particular furnace geometry and operating conditions.

As shown in FIG. 2, the burner can include a submerged oxidant grading nozzle 90 disposed in a fixed spaced relationship with the second portion 27 of the first oxidant conduit 20. The oxidant grading nozzle is used to direct the oxidant stream under the flame, which is generated by introducing fuel and oxidant from the fuel conduit 40 and the first oxidant conduit 20, respectively.

The underarm oxidant staged nozzle 90 has an inlet 91 for receiving the first oxidant gas or the second oxidant gas. The first oxidant gas and the second oxidant gas may be industrial grade oxygen from the same or different sources.

The inlet 91 can include a quick disconnect attachment or other accessory suitable for inspecting the supply of oxidant gas supplied to the underarm oxidant staged nozzle 90.

The underarm oxidant staged nozzle 90 may not require a cooling fluid jacket. The oxidant gas flow through the underarm oxidant staged nozzle may be sufficient to keep the nozzle of the underarm oxidant staged nozzle cool. The oxidant gas introduced into the underarm oxidant staged nozzle 90 is generally the same as the oxidant gas introduced into the first oxidant conduit 20, for example, industrial grade oxygen. However, the oxidant gas introduced into the underarm oxidant staged nozzle may be different from the oxidant gas introduced into the first oxidant conduit 20.

The burner may include a sputum grading nozzle of the crucible shown in FIG. 1 as a second oxidant conduit 80 disposed in a fixed spaced relationship with the second portion 27 of the first oxidant conduit 20. The second oxidant conduit 80 is utilized to direct the flow of oxidant below the flame.

Since the oxidant grading nozzle of the crucible is located in the regenerator crucible, it must be cooled. The second oxidant conduit 80 can be disposed in a fixed spaced relationship with the first cooling fluid jacket 10 or any of the second cooling fluid jackets 70 illustrated in FIG. 1 and disposed substantially concentrically therein.

The burner may additionally include any second cooling fluid jacket 70 and a second oxidant conduit 80 disposed in a fixed spaced relationship with the optional second cooling fluid jacket 70 and disposed substantially concentrically therein. The second cooling fluid jacket 70 may have to prevent the nozzle of the oxidant nozzle from overheating due to the flame and radiant heating of the furnace. Water or other cooling fluid is introduced into the inlet 71 of the optional second cooling fluid jacket 70 and flows around the second oxidant conduit 80, which includes the area around the oxidant discharge end. Water or other cooling fluid is withdrawn from the outlet 73 of the optional second cooling fluid jacket 70.

The second oxidant conduit 80 has an inlet 81 for receiving the oxidant gas or the second oxidant gas, a first portion 83 downstream of the inlet 81, a curved portion 85 downstream of the first portion 83, and a curved portion 85 at the curved portion 85. The second portion 87 downstream. The first oxidant gas and the second oxidant gas may be industrial grade oxygen from the same or different sources.

The inlet 21 may include a quick disconnect accessory or other accessory suitable for inspecting the oxidant gas supply to the oxidant nozzle for the burner.

The first portion 83 can have a circular cross section and can be attached in a tangential manner, for example by welding, to the outer surface of the first portion of the first oxidant nozzle.

The curved portion 85 has an angle, β, wherein the angle, β, is within 15° of the angle, α. The angle, β, can be from 60° to 110°. The second portion 87 of the second oxidant conduit 80 can be inclined upward or downward relative to the second portion 27 of the first oxidant conduit 20. The angle with respect to the second oxidant conduit 80 is defined as being between the straight segment of the first portion 81 of the second oxidant conduit 80 and the straight portion of the second portion 85 of the second oxidant conduit 80. The angle, β, is the compensation angle with respect to the angle of the second oxidant conduit.

The second portion 87 of the second oxidant conduit 80 forms a tip in the nozzle and has a flow axis 82. The second portion 87 of the second oxidant conduit 80 is in a fixed spaced relationship with the second portion 27 of the first oxidant conduit 20. The optional second cooling fluid jacket 70 and the second oxidant conduit 80 can be welded together or attached as part of the burner assembly.

The corner, β, can be within 2° of the angle, α,. The flow axis 82 of the second portion 87 of the second oxidant conduit 80 can be substantially parallel to the flow axis 22 of the second portion 27 of the first oxidant conduit 20. With respect to the flow axis 82 and the flow axis 22, substantially parallel means spaced apart and equidistantly spaced within 10% of the maximum separation distance.

As shown in Figure 1, the outlet end 29 of the second portion 27 of the first oxidant conduit 20 can protrude from the outlet 89 of the nozzle. The outlet end 29 can protrude from the outlet 89 by 0.2 cm to 3 cm. The nozzle of the second oxidant conduit 80 can be recessed relative to the outlet end 29 of the second portion 27 of the first oxidant conduit 20 such that the first cooling jacket and/or the second portion 27 of the first oxidant conduit 20 can shield the The nozzle is not exposed to the flame and/or the furnace.

As shown in detail in Figures 1 and 4, the nozzle of the second portion 87 of the second oxidant conduit 80 has an inlet 88, a transition section and an outlet 89. The inlet 88 can have a circular cross section and a cross-sectional area, A _ni , and the outlet 89 has a non-circular cross section and a cross-sectional area, A _no . The outlet 89 of the nozzle may have a width to height ("W" to "H") ratio of 1.5 to 5. For the purposes of this disclosure, the aspect ratio of the outlet 89 is measured at the discharge face of the nozzle. The width has a larger size relative to the height.

About this nozzle, It can be 1.25 to 5. An area ratio greater than the specified lower limit is essential to minimize oxidant flow non-uniformity at the nozzle exit, and oxidant flow non-uniformity can result in separate or reverse flow, increasing the risk of nozzle corrosion, clogging, and premature failure. In order to avoid an excessively high second oxidant velocity or an unacceptably large second oxidant conduit, an area ratio smaller than the upper limit is required.

The nozzle can have a convergence height and a divergence width. This level of convergence helps to reduce the cross-sectional area necessary to prevent flow separation. The divergence width increases the lateral width of the exposed secondary stream such that it is wider than the flame produced by the first oxidant and fuel. This will increase the uniformity of mixing under the grading oxidant and the underside of the flame. The second portion 87 of the second oxidant conduit 80 can have a convex inner surface adjacent the outlet 89. The convex inner surface enables the effluent stream to be rapidly and smoothly converted into an orientation parallel to the main flow axis 82. The divergence half angle of the width can be 5° to 15°.

Nozzles are often referred to as "convergent" (reduced from a width to a smaller size depending on the direction of flow) or "diverge" (from a smaller dimension to a larger dimension depending on the direction of flow). The de Laval nozzle has a converging section followed by a diverging section and is often referred to as a converging-diverging nozzle.

The converging nozzle accelerates the subsonic fluid. If the nozzle pressure ratio is high enough, the flow will reach a subsonic speed at the narrowest point (i.e., the nozzle throat). In this case, the nozzle is said to be "blocking".

The nozzles described herein are different from the lava type nozzles. In contrast to the nozzle having a divergence width and a convergence height, the lava type nozzle has a converging section followed by a diverging section.

The burner is designed to be inserted into a heat accumulator cartridge as shown in FIG. A hole must be cut into the neck of the heat accumulator to provide a position for insertion into the burner. The hole can be cut into the top, bottom (base) or side of the neck. Preferably, the hole is cut at the bottom of the neck portion.

The burner is insertable through the hole cut through the bottom of the neck, preferably in a substantially vertical orientation as shown in FIG. The burner may include a mounting plate 95 that sets and attaches the burner to the neck portion. The burner discharges the fuel and oxidant oxygen into the furnace combustion space in a substantially horizontal plane.

The burner can be operated in a variety of ways to control the temperature and heat flux distribution in the glass tank and in the heat accumulator. This is achieved in principle by adjusting the distribution of oxygen, the strategic application of which provides for the customization of flame length, brightness and stability, and also contributes to the cooling of the crucible surface.

The combustor can introduce gaseous fuel through the fuel conduit 40 through two or more of the first oxidant gas conduit 20, the oxidant grading nozzle (second oxidant conduit 80), and the underarm oxidant grading nozzle 90. Many introduce one or more oxidant gases to operate.

The invention also relates to a furnace 100, a portion of which is shown in FIG. Although the furnace according to the invention is shown to contain a burner according to Fig. 2, the burner according to Fig. 1 can also be used in conjunction with the furnace and it will be apparent to those skilled in the art that the description of the burner according to Fig. 1 can be adapted. The furnace includes a heat accumulator 125, a furnace combustion chamber 135, and a heat accumulator neck 105 that connects the heat accumulator 125 to the furnace combustion chamber 135. The regenerator jaw neck 105 defines a weir 110 and a weir opening 115 in the wall 120 of the oven 100. The furnace also contains a burner according to the above characteristics. The burner passes through the regenerator jaw neck 105 and into the crucible 110, and the burner is configured to direct fuel and oxidant into the furnace 100.

The heat accumulator neck portion 105 includes a dome (top), a base (bottom) and a side wall, which are often constructed of refractory bricks. The regenerator jaw defines a passage or weir between the regenerator and the opening or opening of the furnace. As used herein, the crucible is a channel and is distinguishable from the opening of the crucible.

The heat accumulator is a heat recovery device utilizing regenerative heat transfer and is well known in the art. Details of the heat accumulator can be found in Wolfgang Trier, "Glass Furnaces, Design Construction and Operation" by KL Loewenstein, Society of Glass Technology, Snow, Earl, UK, 2000, and by Fay Tooley (editor) "The Handbook of Glass Manufacture", Volume 3, Volumes 1 and 2, found in Ashlee Publishing Company (New York), 1984.

As used herein, the regenerator jaw neck is any conduit that is used or previously used to transfer combustion air from the regenerator to the combustion space in the furnace.

The furnace can include a burner that includes any or all of the above characteristics with respect to the burner.

In one embodiment, as shown in Figure 1, a one-stage grading nozzle can be used in the furnace.

In one embodiment, as shown in Figure 2, a conduit 90 passes through the furnace wall 120 below the crucible opening 115 and is configured to introduce the oxidant into the furnace. The conduit 90 is a submerged oxidant grading nozzle. The conduit is "under" the opening if the pipe that is pulled vertically upward from the nozzle intersects the weir. Vertically means completely straight up or down.

The furnace can include both a sulphurizing agent grading nozzle and an underarm oxidizing agent grading nozzle.

The furnace also includes a molten pot disposed below and adjacent to the combustion chamber of the furnace, a fill end for introducing glass forming components into the molten bath, and a discharge end for removing glass product from the molten pot. The glass forming component is filled into the molten bath basin of the furnace and melted by the heat of the combustion flame in the combustion chamber of the furnace. Molten glass flows from the packed end to the discharge end and is withdrawn from the furnace as a product. The extracted molten glass is subjected to a forming operation to form the glass into a form of a glass plate, a glass fiber, a container or other desired product.

The furnace also contains an exhaust gas enthalpy in the furnace wall to extract combustion products from the furnace combustion chamber. Fuel and oxidant are introduced into the furnace combustion chamber via a burner in the neck of the heat accumulator, combusted to form a flame and transfer heat to the glass forming components and molten glass. The combustion products from the reaction of the fuel and oxidant are removed from the combustion chamber of the furnace through the exhaust vent.

The invention also relates to a method of heating a furnace, for example during the repair of the heat accumulator. After a long period of operation of the furnace, the heat transfer packing or inspection equipment in the regenerator may be blocked or deteriorated by the condensed volatiles of the glass kiln. The furnace still has to be heated when the air fuel enthalpy is stopped in order to repair the heat accumulator. It is preferred to provide sufficient heat for maintaining glass production.

This method can also be used to extend the life of the furnace without the need to repair the degraded regenerator or increase the production rate of the current furnace.

The burner described above can be used in a method of heating a furnace while repairing the heat accumulator to extend the life of the furnace without repairing the heat accumulator and/or increasing the production rate of the current furnace.

A method of heating a furnace includes blocking air flow to the crucible; terminating the combustion flow to an air fuel burner associated with the crucible; establishing the burner such that the burner passes through the regenerator jaw neck and enters the crucible; The coolant passes through the first cooling fluid jacket; the first oxidant gas is introduced into the furnace through the first oxidant conduit; and the fuel or different fuel used during the previous air fuel operation is introduced into the furnace through the fuel conduit.

The method also includes combusting the selected fuel with the first oxidant gas to form a combustion product; and removing the combustion products from the furnace combustion chamber through an exhaust pipe.

During the regenerator repair, it is necessary to stop the air passing through the portion of the accumulator inspection device assembly so that the degraded inspection device can be removed and an alternative inspection device set up. The heat accumulator can be either an open box design or a divided grid design. Air flow can be blocked or blocked at the bottom of the heat accumulator. It is also expedient to block or block the flow of air at the upstream end of the heat accumulator.

The regenerator jaw neck can be cut or modified to provide a hole for setting up the burner. The hole in the neck of the heat accumulator can be at the bottom or base of the neck of the heat accumulator shown in FIG. The hole can also be cut into either side of the neck of the heat accumulator or the vault or top of the neck of the heat accumulator.

The burner can be set up such that the burner passes through the regenerator jaw neck and into the crucible. The distance from the outlet end of the second portion of the first oxidant conduit to any of the neck walls and the distance from the outlet end of the second portion of the fuel conduit from any of the neck walls can be set by the position of the mounting plate 95 .

Typically, a coolant, preferably water, will pass through the first cooling fluid jacket during installation of the burner within the neck of the regenerator to prevent overheating of the burner during set up.

Once established, the first oxidant gas will be introduced into the furnace through the first oxidant conduit and fuel will be introduced into the furnace through the fuel conduit. The fuel may be the same as the fuel that was previously operated by the air fuel, or different fuels may be used if necessary. The fuel can be natural gas.

The method can additionally include introducing the first oxidant gas or the second oxidant gas into the furnace through a second oxidant conduit.

The method may additionally include introducing a quantity of air through the heat accumulator. This air can pass through the heat accumulator or come from another source. The air thus introduced has at least three beneficial effects. First, it cleans the enthalpy of flue gas and particulate recirculation, thereby minimizing corrosion and accumulated particulates within the crucible. Second, it adds momentum to the flame. Finally, it reduces the oxidant flowing to the burner, which in turn reduces operating costs and slows down the rate of combustion near the burner nozzle. The slower burning rate will generally expand and enhance the bright areas of the flame, thereby increasing the radiant heat transfer. Up to 25% of the stoichiometric oxygen demand of the burner can be supplied via the flow of air through the crucible. Part of the oxygen demand is provided by the air passing through the helium, and from 95% to about 75% of the stoichiometric oxidant required for complete combustion of the fuel to the combustor can be by the first oxidant gas and/or The second oxidant gas is supplied.

The heat accumulator can be repaired at that time, while the operation of the burner provides heat to the furnace and continues to produce glass.

Otherwise the furnace can be operated continuously in this mode without repairing the heat accumulator until the furnace activity is over.

Some limitations regarding the range of parameters of the burner are determined by the geometry of the burner and crucible of the regenerative glass kiln (i.e., available space). To help determine other limitations of these ranges, computational fluid dynamics (CFD) modeling was applied in the manner described in the following examples.

Example

The CFD model was used to separate and examine the effects of design and operating parameters on the mechanical and thermal phenomena of the combustor fluid. The burner and associated second oxidant illustrated in Figure 1 are used as a base modelling configuration. The parameters that produce changes during the period of modeling are provided in Table 1, and their respective ranges. Note that although the graded oxidant flow rate, which is the total percentage of the (first plus second) oxidant flow, is not a design parameter for the burner, it is still included herein because of variations in this embodiment. Help to further emphasize the impact of other parameters. Assume that the fuel is natural gas, with its imitation of 100% methane.

For practical reasons, only the most significant CFD results are presented.

The burner dimensionless length, L/D, is varied by the maximum value of the first oxidant and fuel surface flow cross-sectional area ratio (see Table 1). The results are summarized in Figures 6 to 9.

For example, the effect of L/D on peak flame temperature is illustrated in Figure 6. Note that although the trend for this 20% grading case shows a gradual and relatively small increase in temperature as L/D decreases, the peak flame for the 80% grading case when L/D is reduced from 2.7 to 1.4 for 80% oxidant The temperature increases by nearly 100 K and then decreases as L/D drops further to 0.8. Since the peak flame temperature is increased by less than 100 K for an L/D of 0.8 to 2.7, and the L/D greater than 2.7 may have a lower peak flame temperature, it is suitable for an L/D of 0.8 to 7. The burner can operate in the L/D range beyond 0.8 to 7.

Figure 7 gives a closer examination of the flame temperature for a case involving 80% grading, which compares the flame temperature distribution with L/D equal to 0.8, 1.4 and 2.7. The first thing to note is that the peak temperatures of all three cases occur fairly close to the burner nozzle; thus, the deviation of the peak value may expose the burner metal to high temperature damage. Furthermore, as far as L/D is equal to 1.4 and 2.7, the flame temperature is initially increased, reaching a sharp peak at a distance of approximately 0.5 m from the nozzle exit. However, as far as L/D is equal to 0.8, the peak temperature occurs at a distance of less than 0.2 m from the nozzle outlet, thus further increasing the risk of overheating of the nozzle. Also of interest is the case where the L/D is equal to 0.8. The flame temperature reaches the lower limit immediately after reaching the peak, reaching a local minimum, which is between 150 and 200K lower than the temperature of the other two cases. These characteristics suggest that a more extreme flame property shift occurs between L/D equal to 1.4 and 0.8 than L/D equals 2.7 and 1.4.

The explanation of the flame property offset is inferred from the nozzle exit velocity profile of the L/D equal to 1.4 and 0.8 cases provided in Figures 8a and 8b, respectively. In particular, although the path of the fuel/first oxidant mixture remains substantially unchanged for the second case, the path of the second oxidant changes significantly as L/D changes. That is, the second oxidant pathway is substantially parallel to the first oxidant/fuel stream as far as L/D is equal to 1.4. However, when L/D drops to 0.8, the graded oxidant flows, there is not a sufficient development length in the second oxidant nozzle, and it is nearly 4 degrees upward toward the main fire. This results in rapid convergence between the flame and the second oxidant, which, when combined with a larger amount of the second oxidant (80% of the total oxidant as a graded oxidant), produces accelerated mixing near the burner tip, causing the The peak temperature is closer to the nozzle and the subsequent minimum temperature becomes lower than in other cases. The practical effect of these findings is that when the burner contains a second oxidant conduit, the minimum value of L/D should be greater than or equal to 1.4. However, since the characteristics of the fuel/first oxidant stream are not greatly affected by the change from L/D equal to 1.4 to 0.8, when the burner does not contain the second oxidant conduit, the minimum value of L/D should be greater than or equal to 0.8.

The effect of L/D on the length of the flame, illustrated in Figure 9, will reinforce the conclusions described in Figures 6-8. This graph shows why the L/D reduction results in a shortening of the flame, perhaps due to insufficient development of the reactant velocity profile within the burner and the staged nozzle, resulting in accelerated mixing. The flame shortening effect between the case of L/D between 1.4 and 0.8 for this 80% oxidant classification is particularly severe and can be again attributed to the rapid convergence between the aforementioned primary and secondary nozzle flows.

The first oxidant area ratio was varied by a burner-free length of 0.8 and 1.4, L/D. The peak flame temperature is shown to be sensitive to the first oxidant area ratio. Figure 10 shows that L/D is equal to 1.4 and 20% and 80% oxidant grading is treated as the peak temperature The function. When the area ratio From 1.9 to 1.0, an 80% grading occurs with a peak temperature increase of 190 K, whereas a 20% grading occurs with a peak temperature increase of 230 K. Regarding the latter case, when The peak temperature rises steeper from 1.3 to 1.0. The case of L/D equal to 0.8 in Fig. 11 shows similar results. As shown in Figure 10, when When the temperature drops below 1.3, the peak temperature increases sharply. The highest peak flame temperature for all cases is A value in the range of 2600 to 2650 K is reached when it is equal to 1.0.

Other comparisons are presented in Figure 12 A case of the flame temperature distribution of the 80% classification case equal to 1.0 and 1.9. The temperature distribution for the second case again shows the characteristic peak near the burner exit. Note that the location of the spike will always be from When it is equal to 1.9, the distance from the burner nozzle is shifted by approximately 0.4 m to Equal to 1.0 is approximately 0.2 m from the nozzle. Because it is a combination of peak temperature and peak position that defines the relative risk of nozzle overheating, the conclusion is that less than 1.3 should be avoided. value.

The mechanism by which the effect of varying the area ratio of the oxidant changes the flame resistance is a cross-sectional view through the velocity of the first oxidant outlet. In other words, reduce the ratio Improper distribution of the first oxidant flow at the exit of the burner nozzle will be increased, thereby creating excessive turbulence and shear forces that increase the peak flame temperature and shorten the flame length. One way to measure the amount of improperly assigned velocity is to calculate the velocity deviation, which is defined as the standard deviation of the local velocity obtained from the average of the cross-section. In accordance with the teachings of the present invention, a higher velocity deviation corresponds to a greater degree of non-uniformity resulting in an undesirably higher mixing rate between the fuel and the first oxidant. Table 2 lists the area ratio corresponding to the first oxidant Equal to 1.0, 1.3, and 1.9; L/D is equal to 1.4; 20% graded speed deviation. The magnitude of the deviation, normalized to the average section speed percentage, indicating when the area ratio The first oxidant non-uniformity doubled from 1.9 to 1.0. Again, with Compared to a substantial increase from 1.3 to 1.0, it shows A relatively small increase in speed deviation from 1.9 to 1.3, which further indicates that the first oxidant area ratio must be maintained at or above 1.3 .

Regarding the fuel area ratio, Decreasing this parameter to a range of 1.9 to 1.0 has a qualitatively similar effect on the peak flame temperature as changing the first oxidant area ratio (to the same range). However, this effect is small in size. For example, with L/D equal to 0.8, a fuel area ratio reduced from 1.9 to 1.0 produces a 70 K increase in peak flame temperature, while a flame temperature increase of 250 K is produced by the same reduction in the first oxidant area ratio (see figure). 11).

The lower sensitivity of the flame characteristic to the fuel nozzle area ratio can be traced back to the fact that the fuel nozzle exit velocity profile is not like the first oxidant outlet velocity profile, as compared to the sensitivity to the first oxidant area ratio. It is as sensitive as the area ratio change. As indicated in the document in Table 3, the fuel area ratio . The fuel velocity deviation at the nozzle outlet equal to 1.0 and 1.9 is less than half the equivalent value for the first oxidant (see Table 2). Fuel area ratio less than 1.0 Not intended because it tends to be unstable with the flow separation effect. Thus, based on the CFD modeling, any fuel nozzle area ratio greater than or equal to 1.0, It is acceptable in this invention. However, flame property measurements and observations made during laboratory prototype testing indicate the application of a fuel area ratio greater than 1.37, and the concave to convex profile illustrated in Figure 3 will further improve the burner. efficacy.

The ratio of the flow cross-sectional area of the second oxidant conduit, The second oxidant velocity profile exiting the nozzle is strongly influenced, which in turn affects both the performance and durability of the burner system. Conditions of interest for the present invention, 1.0= =1.55, CFD modeling results confirm the strong impact on velocity distribution. Figure 13 shows when the area ratio, The velocity deviation of the second oxidant will increase sharply as it falls below a value of approximately 1.25, as indicated by the increased slope in the curve. Although these results imply that the effect on combustion performance is small within this range, the collapse of the nozzle exit velocity profile at an area ratio below this threshold results in a very low exit velocity zone, such very low exit velocity. The zone tends to be unstable and can lead to separation or reverse flow. This will increase the risk of nozzle corrosion and blockage and may result in more frequent maintenance and higher failure rates. For its part, the minimum acceptable area ratio for the second oxidant nozzle of the present invention Is 1.25.

A _fi ‧‧‧section section of the entrance section

A _fo ‧‧‧section section of the exit section

A _i ‧‧‧ entrance section cross-sectional area

A _o ‧‧‧section section of the exit section

A _ni ‧‧‧inlet cross-sectional area

A _no ‧‧‧export cross-sectional area

‧‧‧‧Bend angle of the bend

‧‧‧‧Bend angle of the bend

D‧‧‧First cooling fluid jacket outer equivalent diameter

W‧‧‧Nozzle exit width

H‧‧‧Nozzle exit height

L‧‧‧First cooling fluid jacket length

1‧‧‧ burner

10‧‧‧First cooling fluid jacket

13‧‧‧Exit of the first cooling fluid jacket

11‧‧‧ Entrance to the first cooling fluid jacket

20‧‧‧First oxidant conduit

twenty one. . . Entrance for receiving oxidant gas

twenty two. . . Second part flow axis

twenty three. . . First part

25. . . Bending part

27. . . Second part

29. . . Second end of the outlet

40. . . Fuel conduit

41. . . Entrance for receiving fuel

42. . . Second part flow axis

43. . . First part

45. . . Bending part

47. . . Second part

49. . . Second end of the outlet

50. . . Oxidant channel

51. . . Entrance section

53. . . Transition

55. . . Export section

60. . . Fuel passage

61. . . Entrance section

63. . . Transition

65. . . Export section

70. . . Second cooling fluid jacket

71. . . Entrance

73. . . Export

80. . . Second oxidant conduit

81. . . Entrance

82. . . Second part flow axis

83. . . First part

85. . . Bending part

87. . . Second part

88. . . Nozzle inlet

89. . . Nozzle outlet

90. . . Underarm oxidant graded nozzle

91. . . Entrance

95. . . Mounting plate

100. . . stove

101. . . burner

105. . . Heat accumulator neck

110. . . port

115. . . Opening

120. . . Furnace wall

125. . . Heat accumulator

135. . . Furnace combustion chamber

Figure 1 shows a tunneling burner with any sulphuric acid grading nozzle.

Figure 2 shows a piercing burner in the neck of a regenerator set up in a furnace with a submerged oxidant staged nozzle.

Figure 3 shows an enlarged schematic view of the first oxidant conduit and the discharge end of the fuel conduit.

Figure 4 shows an enlarged schematic view of the discharge end of the underarm oxidant staged nozzle.

Figure 5 is a graph of normalized heat flux as a function of distance from a burner nozzle in a test furnace.

Figure 6 is a graph showing the results of modeling the peak flame temperature as a function of dimensionless nozzle length.

Figure 7 is a graph showing the results of modeling as a function of the flame temperature as a function of the distance from the burner nozzle exit.

Figure 8a is a velocity contour map derived from the modeled results.

Figure 8b is a velocity contour map derived from the modeled results.

Figure 9 is a graph showing the results of modeling the flame length as a function of dimensionless nozzle length.

Figure 10 is a graph showing the results of modeling as a function of temperature as a ratio of oxygen passage area.

Figure 11 is a graph showing the results of modeling as a function of temperature as a ratio of oxygen passage area.

Figure 12 is a graph showing the results of modeling as a function of the length of the flame as a distance from the exit of the burner nozzle.

Figure 13 is a graph showing the results of modeling as a function of the second oxidant velocity deviation as a function of the second oxidant channel area ratio.

‧‧‧‧Bend angle of the bend

‧‧‧‧Bend angle of the bend

D‧‧‧First cooling fluid jacket outer equivalent diameter

1‧‧‧ burner

L‧‧‧First cooling fluid jacket length

10‧‧‧First cooling fluid jacket

11‧‧‧ Entrance to the first cooling fluid jacket

13‧‧‧Exit of the first cooling fluid jacket

20‧‧‧First oxidant conduit

21‧‧‧Inlet for receiving oxidant gas

22‧‧‧Second part flow axis

23‧‧‧ first part

25‧‧‧Bending parts

27‧‧‧Second part

29‧‧‧Exit end of the second part

40‧‧‧fuel conduit

41‧‧‧ Entrance for receiving fuel

42‧‧‧Second part flow axis

43‧‧‧First part

45‧‧‧Bending parts

47‧‧‧Second part

49‧‧‧Exit end of the second part

50‧‧‧Oxidant channel

51‧‧‧ entrance section

53‧‧‧Transition

55‧‧‧Exit section

60‧‧‧ fuel passage

61‧‧‧ entrance section

63‧‧‧Transition

65‧‧‧Exit section

70‧‧‧Second cooling fluid jacket

71‧‧‧ entrance

73‧‧‧Export

80‧‧‧Second oxidant conduit

81‧‧‧ entrance

82‧‧‧Second part flow axis

83‧‧‧ first part

85‧‧‧Bending parts

87‧‧‧Second part

88‧‧‧Nozzle entrance

89‧‧‧Nozzle exit

Claims (27)

A burner comprising: a first cooling fluid jacket having an outer equivalent diameter, D; a first oxidant conduit in fixed spaced relationship with the first cooling fluid jacket and disposed substantially concentrically therein, The first oxidant conduit has an inlet; a first portion downstream of the inlet of the first oxidant conduit; and a curved portion downstream of the first portion of the first oxidant conduit, the curved portion of the first oxidant conduit has a 45° to a corner of 120°, α, and a second portion downstream of the curved portion of the first oxidant conduit, the second portion of the first oxidant conduit forming a tip at the outlet end and having a flow axis and length, L; a fuel conduit having an inlet; a first portion downstream of the inlet of the fuel conduit, wherein the first portion of the fuel conduit is in fixed spaced relationship with the first portion of the first oxidant conduit and is disposed substantially concentrically a curved portion, wherein the curved portion of the fuel conduit is in a fixed spaced relationship with the curved portion of the first oxidant conduit and substantially the same Centered therein; and a second portion having an end at the outlet end and having a flow axis, wherein the second portion of the fuel conduit is in a fixed spaced relationship with the second portion of the first oxidant conduit and is substantially concentrically disposed Having therein an oxidant passage between a second portion of the fuel conduit and a second portion of the first oxidant conduit; wherein the oxidant passage has an inlet section, a transition section downstream of the inlet section, and at the transition An outlet section downstream of the section, wherein the inlet section has a cross-sectional area, A _i , the outlet section has a cross-sectional area, A _o , and and . The burner of claim 1, wherein the second portion of the fuel conduit defines a fuel passage, wherein the fuel passage has an inlet section, a transition section downstream of the inlet section, and an outlet section downstream of the transition section Wherein the inlet section of the second portion of the fuel conduit has a cross-sectional area, A _fi , and the outlet section of the second portion of the fuel conduit has a cross-sectional area, A _fo , wherein The burner of claim 1, wherein the second portion of the fuel conduit defines a fuel passage, wherein the fuel passage has an inlet section, a transition section downstream of the inlet section, and an outlet section downstream of the transition section Wherein the inlet section of the second portion of the fuel conduit has a cross-sectional area, A _fi , and the outlet section of the second portion of the fuel conduit has a cross-sectional area, A _fo , wherein The burner of claim 2, wherein the second portion of the fuel conduit has a concave inner surface and a convex inner surface in the transition section of the fuel passage, wherein the convex inner surface of the fuel conduit Downstream of the concave inner surface of the fuel conduit. The burner of claim 1, wherein the outlet end of the second portion of the first oxidant conduit projects from the second portion of the fuel conduit by from 0.2 cm to 3 cm. The burner of claim 1, further comprising: an optional cooling fluid jacket; and a second oxidant conduit fixed to at least one of the first cooling fluid jacket and the second cooling fluid jacket a second oxidant conduit having an inlet, a first portion downstream of the inlet of the second oxidant conduit, and a curved portion downstream of the first portion of the second oxidant conduit, a curved portion of the second oxidant conduit having an angle β, the angle β is within 15° of the angle α; and a second portion downstream of the curved portion of the second oxidant conduit, the second oxidant a second portion of the conduit forming a tip in the nozzle and having a flow axis, the second portion of the second oxidant conduit being in a fixed spaced relationship from the second portion of the first oxidant conduit; . The burner of claim 6, wherein the angle, β is within 2° of the angle, α, and wherein the flow axis of the second portion of the second oxidant conduit is substantially parallel to the A flow axis of the second portion of the first oxidant conduit. The burner of claim 6, wherein the nozzle has an inlet and an outlet, and wherein the outlet end of the second portion of the first oxidant conduit protrudes from the nozzle outlet of the second portion of the second oxidant conduit. Cm to 3cm. The burner of claim 6, wherein the nozzle of the second portion of the second oxidant conduit has an inlet and an outlet, and wherein the inlet has a circular cross section and a cross-sectional area, A _ni , and the outlet has A non-circular cross section and a cross-sectional area, A _no , wherein the outlet of the nozzle has an aspect ratio of 1.5 to 5. Such as the burner of claim 9 of the patent scope, wherein . The burner of claim 9, wherein the nozzle has a convergence height and a divergence width. A burner according to claim 9 wherein the nozzle has a concave surface transition between a circular cross section and a non-circular cross section. The burner of claim 1, wherein the second portion of the first oxidant conduit has a convex inner surface in the transition of the oxidant passage. The burner of claim 1, wherein the second portion of the fuel conduit has a concave outer surface in the transition of the oxidant passage. A burner according to claim 6 wherein 60° < a < 110° and 60° < β < 110°. The burner of claim 1, wherein the second portion of the first oxidant conduit has a circular cross section. The burner of claim 1, wherein the second portion of the fuel conduit has a circular cross section. The burner of claim 1, wherein the flow axis of the second portion of the first oxidant conduit is straight and substantially parallel or substantially coincident with the flow axis of the second portion of the fuel conduit. A furnace comprising: a heat accumulator; a furnace combustion chamber; a regenerator crucible, the regenerator connected to the furnace combustion chamber, the regenerator neck defining a wall in the furnace wall And a burner according to any one of claims 1 to 18, wherein the burner passes through the regenerator neck and enters the crucible, and the burner is configured to introduce fuel and oxidant The stove burns the cabin. The furnace of claim 19, further comprising: a molten trough disposed below the combustion chamber of the furnace, the molten trough having a filling end for introducing a glass forming component into the melting trough and from the melting trough The discharge end of the glass product is removed; and an exhaust gas enthalpy in the wall or another wall of the furnace is used to extract combustion products from the combustion chamber of the furnace. A furnace comprising: a heat accumulator; a furnace combustion chamber; a regenerator crucible, the regenerator connected to the furnace combustion chamber, the regenerator neck defining a wall in the furnace wall And a burner according to claim 6, wherein the first cooling jacket, the first oxidant conduit and the fuel conduit pass through the regenerator neck and enter the crucible, the first oxidant The conduit is configured to direct an oxidant into the furnace, the fuel conduit is configured to direct fuel into the furnace, and wherein the second oxidant conduit passes through the furnace wall at a location below the bore opening, the second oxidant conduit is configured The oxidant can be introduced into the furnace. The furnace of claim 21, further comprising: a melting trough disposed below the combustion chamber of the furnace, the molten trough having a filling end for introducing a glass forming component into the melting trough and removing the molten trough from the melting tank The discharge end of the glass product; and the exhaust gas enthalpy in the wall or the other wall of the furnace for extracting combustion products from the combustion chamber of the furnace. A method of heating a furnace having a heat accumulator coupled to a furnace combustion chamber heat accumulator neck, the heat accumulator neck defining a weir and a weir opening in a wall of the furnace, the method comprising: blocking Flowing of the air to the crucible; terminating the flow of a fuel to the air-fuel burner associated with the crucible; establishing a combustor as defined in any one of claims 1 to 18 such that the burner passes through the accumulator Necking the neck and entering the crucible; passing the coolant through the first cooling fluid jacket and, if present, through the second cooling fluid jacket; introducing the first oxidant gas through the first oxidant conduit into the furnace combustion chamber; The fuel conduit introduces the fuel or another fuel into the furnace combustion chamber; the fuel or another fuel is combusted with the first oxidant gas to form a combustion product; and the combustion product is withdrawn from the furnace combustion chamber through an exhaust pipe. The method of claim 23, further comprising continuously burning air through the crucible in an amount of more than 5% to less than or equal to 25% of the combustion of the fuel or another fuel passing through the combustor The amount of stoichiometric air required. The method of claim 24, wherein the first oxidant gas comprises 28% to 100% by volume of oxygen. The method of claim 24, wherein the burner is defined by any one of claims 5 to 12 and 18, and additionally comprising: passing the first oxidant gas through the second oxidant conduit Or a second oxidant gas is introduced into the furnace combustion chamber. The method of claim 26, wherein the second oxidant gas comprises 28% to 100% by volume of oxygen.