Burner, system and method for hydrogen-enhanced pulverized coal ignition

Abstract

A burner includes a first pulverized coal entrained fluid flow conduit; an inner hydrogen conduit; and a hydrogen oxidant conduit located between the first pulverized coal entrained fluid flow conduit and the inner hydrogen conduit; an outlet of the inner hydrogen conduit is located at a first distance from an outlet of the hydrogen oxidant conduit such that hydrogen output from the outlet of the inner hydrogen conduit reaches the outlet of the hydrogen oxidant conduit through a portion of the hydrogen oxidant conduit; the outlet of the hydrogen oxidant conduit is a second distance away from the outlet of the first pulverized coal entrained fluid flow conduit; the first pulverized coal entrained fluid flow conduit is configured such that the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit pass through a portion of the first pulverized coal entrained fluid flow conduit to be output from the burner.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. non-provisional patent application No. 17 / 863,228, filed on July 12, 2022. Technical Field

[0003] The present invention relates to boilers, burners, burners for such devices, the operation of such devices and the operation of burners used in conjunction with such devices. Background Art

[0004] Boilers and other types of burners may include a combustion chamber in which pulverized coal is burned. Examples of such devices and systems that may utilize such devices may be understood from U.S. Patent Application Publication No. 2010 / 0007794 and U.S. Patent Nos. 4,495,874, 6,968,791, 7,717,701, 8,578,892, 8,636,500, 8,689,710, 9,243,799, and 9,709,269.

[0005] Traditionally, in pulverized coal boilers, diesel, propane or natural gas is used for ignition at the start of combustion. Such fuel sources help initiate combustion because these fuels can be ignited more easily than pulverized coal.

[0006] In some cases, plasma ignition systems can be used in pulverized coal boilers. Plasma ignition systems are generally designed to generate high-energy plasma from a plasma torch at the burner tip to initiate fuel ignition and flame generation. Plasma torches generally use high-voltage electricity as their energy source. Summary of the invention

[0007] It is determined that pulverized coal fired boilers have historically utilized light fuel oil for cold boiler ignition and heating. However, this method results in undesirable particle and carbon monoxide (CO) emissions and has relatively high operating costs. Plasma torches have also been used in such boilers, but their capital cost is high, frequent maintenance is required, water cooling is required, and operational flexibility is limited. The embodiments of the boiler, burner, burner nozzle, method for operating the burner nozzle, and method for operating the boiler and / or burner of the present invention can provide significant improvements to these methods by reducing maintenance and capital costs and operating costs, while also promoting a more environmentally friendly combustion of the fuel, which can at least reduce the particles included in the emissions. In some specific implementations, in addition to providing reduced particles in the emissions, NOx emissions can also be reduced while reducing CO formation. The embodiments can be configured to utilize enhanced combustion dynamics to provide improved performance and provide a more environmentally friendly operation of the boiler.

[0008] For example, embodiments may provide a significant reduction in particulate matter because utilizing hydrogen as a secondary fuel may avoid the formation of particles compared to using diesel or fuel oil. Additionally, the ability to avoid the use of diesel or fuel oil may avoid the need for on-site storage tanks for such fuels, which may further avoid environmental issues associated with fuel storage and avoid accidental spills of such fuels.

[0009] In addition, it is determined that the embodiment can allow improved operation and provide improved ease of use and maintainability while maintaining low capital and operating costs. For example, most large power plants that can use one or more pulverized coal burners have stored hydrogen on site to be used as a turbine generator cooling medium. The embodiment can also be suitable for utilizing this on-site hydrogen to use hydrogen as a fuel for boilers. In addition, the embodiment can utilize a relatively low-cost burner with a turndown ratio that can be equal to or greater than 10:1, can require minimal maintenance, and provide improved durability. Such advantages can provide a significant improvement to conventional burner technology, which also provides a significant improvement in the environmentally friendly operation of the boiler, burner and / or burner of such an embodiment.

[0010] In a first aspect, a burner for a combustion chamber is provided. An embodiment of the burner may include a first pulverized coal entrained fluid flow conduit, an inner hydrogen conduit, and a hydrogen oxidant conduit located between the first pulverized coal entrained fluid flow conduit and the inner hydrogen conduit. The outlet of the inner hydrogen conduit may be located at a first distance from the outlet of the hydrogen oxidant conduit, so that hydrogen output from the outlet of the inner hydrogen conduit passes through a portion of the hydrogen oxidant conduit to reach the outlet of the hydrogen oxidant conduit. The outlet of the hydrogen oxidant conduit may be a second distance from the outlet of the first pulverized coal entrained fluid flow conduit, so that hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit pass through a portion of the first pulverized coal entrained fluid flow conduit to be output from the burner.

[0011] In a second aspect, the first pulverized coal entrained fluid flow conduit may include an annular conduit for pulverized coal flow entrained in a fluid (e.g., air, oxygen-enriched air, a mixture of air and hydrogen, a mixture of oxygen-enriched air and hydrogen, etc.), and the hydrogen oxidant conduit may include an annular conduit for a hydrogen oxidant flow (e.g., air, oxygen-enriched air, other types of oxidant flows including oxygen concentrations within a preselected oxygen concentration range, etc.). In such embodiments, the inner hydrogen conduit may have a circular or elliptical cross-sectional shape with a single central passage for hydrogen flow; or, for such embodiments, another type of cross-sectional shape.

[0012] In a third aspect, the secondary oxidant conduit can be located near the periphery of the first pulverized coal entrainment fluid flow conduit so that the secondary oxidant flow passes through the burner and enters the combustion chamber. At least one swirler can be located in the secondary oxidant conduit so that the secondary oxidant flow swirls within the combustion chamber. The secondary oxidant can be secondary air, oxygen-enriched air, or other types of oxidant flows including an oxygen concentration within a preselected oxygen concentration range.

[0013] In a fourth aspect, the second pulverized coal entrainment fluid flow conduit can be located near the periphery of the first pulverized coal entrainment fluid flow conduit, so that the first pulverized coal entrainment fluid flow conduit is between the second pulverized coal entrainment fluid flow conduit and the hydrogen oxidant conduit. The secondary oxidant conduit can be located near the periphery of the second pulverized coal entrainment fluid flow conduit so that the secondary oxidant flow passes through the burner and enters the combustion chamber.

[0014] In a fifth aspect, a mixing conduit may be located in the portion of the first pulverized coal entrained fluid flow conduit, and the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit pass through the mixing conduit to be output from the burner (e.g., the hydrogen and hydrogen oxidant may pass through the mixing conduit before being output from the burner). In such embodiments, a flow splitter may be optionally provided. The flow splitter may be positioned to surround the outer peripheral portion of the outlet region of the hydrogen oxidant flow conduit in the first pulverized coal entrained fluid flow conduit to split the first pulverized coal entrained fluid flow into a first inner flow portion and a second outer flow portion, the first inner flow portion including coal particles therein, so that the first portion is directed to the inlet of the mixing conduit to pass through the mixing conduit, and the second outer flow portion passes along the outside of the mixing conduit. The flow splitter may be attached to the mixing conduit to be integrated with the mixing conduit, or may be fastened, welded or otherwise bonded to the mixing conduit. In some embodiments, the splitter can be located at a position within the first pulverized coal entrained fluid flow conduit so that it is between the first pulverized coal entrained fluid flow conduit and the hydrogen oxidant conduit, adjacent to the outlet of the hydrogen oxidant conduit, so as to transfer the first inner flow portion along the channel defined between the splitter and the hydrogen oxidant conduit, thereby mixing the pulverized coal in the first inner portion with the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit in the mixing conduit.

[0015] In the sixth aspect, the outlet of the hydrogen oxidant conduit can be a tapered outlet having a tapered portion, and a gap can be defined between the outlet of the hydrogen oxidant conduit and the mixing conduit, so that the first portion of the pulverized coal passing through the first pulverized coal entraining fluid flow conduit passes through the gap to mix with the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit in the mixing conduit, while the second portion of the pulverized coal passing through the first pulverized coal entraining fluid flow conduit passes along the outside of the mixing conduit.

[0016] In a seventh aspect, the outlet of the hydrogen oxidant conduit may be an enlarged outlet having an enlarged portion, and a gap may be defined between the outlet of the hydrogen oxidant conduit and the mixing conduit, so that a first portion of the pulverized coal passing through the first pulverized coal entrained fluid flow conduit passes through the gap to mix with hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit within the mixing conduit, while a second portion of the pulverized coal passing through the first pulverized coal entrained fluid flow conduit passes along the outside of the mixing conduit. This arrangement may result in the outermost portion of the enlarged outlet portion of the outlet of the hydrogen oxidant conduit extending beyond the inlet of the mixing conduit. This may result in the enlarged outlet portion protruding into the first pulverized coal entrained fluid flow conduit, and may affect how the flow of a portion of the pulverized coal entrained in the fluid is transferred to the inlet of the mixing conduit and toward the outlet of the first pulverized coal entrained fluid flow conduit. In some embodiments, the gap can be sized and configured so that coal particles of a first size are located within a first portion of the pulverized coal passing through the gap, while coal particles of a second size that are larger than the first size do not pass through the gap, but instead pass along the outside of the mixing conduit as they pass through the first pulverized coal entrainment fluid flow conduit to reach the outlet of the conduit for output from the burner.

[0017] In an eighth aspect, a first pulverized coal entrained fluid flow conduit may be positioned to receive a flow of pulverized coal entrained within a fluid including hydrogen. Hydrogen may be injected into the flow of pulverized coal entrained within the fluid prior to supplying the fluid (e.g., air, oxygen-enriched air, other fluid) to the first pulverized coal entrained fluid flow conduit. A control valve may be provided to help control the amount of hydrogen injected. The control valve may be adjustable from a closed position capable of stopping hydrogen injection and at least one open position for providing hydrogen injection at one or more hydrogen injection rates.

[0018] In a ninth aspect, a flow divider may be located between the first pulverized coal entraining fluid flow conduit and the hydrogen oxidant conduit, adjacent to the outlet of the hydrogen oxidant conduit, to divert a portion of the pulverized coal along a passage defined between the flow divider and the hydrogen oxidant conduit, thereby mixing the portion of the pulverized coal with hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit within the mixing conduit. In some embodiments, the mixing conduit may be provided downstream of the outlet of the inner hydrogen conduit and / or the outlet of the hydrogen oxidant conduit.

[0019] In a tenth aspect, a boiler is provided. The boiler may utilize at least one burner, the at least one burner including the first aspect discussed above and one or more aspects of the second to ninth aspects. For example, the boiler may include at least one burner positioned to generate at least one flame in a combustion chamber. The at least one burner may include a first burner, the first burner including a first pulverized coal entrained fluid flow conduit, an inner hydrogen conduit, and a hydrogen oxidant conduit located between the first pulverized coal entrained fluid flow conduit and the inner hydrogen conduit. The outlet of the inner hydrogen conduit may be located at a first distance from the outlet of the hydrogen oxidant conduit, so that the hydrogen output from the outlet of the inner hydrogen conduit passes through a portion of the hydrogen oxidant conduit to reach the outlet of the hydrogen oxidant conduit. The outlet of the hydrogen oxidant conduit may be a second distance from the outlet of the first pulverized coal entrained fluid flow conduit, so that the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit pass through a portion of the first pulverized coal entrained fluid flow conduit to be output from the burner.

[0020] In an eleventh aspect, the boiler further comprises a pulverized coal source connected to the inlet of the first pulverized coal entrained fluid flow conduit, a hydrogen source connected to the inlet of the inner hydrogen conduit, and an oxidant stream source connected to the inlet of the hydrogen oxidant conduit. The hydrogen source may include a container containing hydrogen or a processing unit that outputs a hydrogen stream. The pulverized coal source may include, for example, a container for storing pulverized coal or a pulverizing unit that outputs pulverized coal. The oxidant stream source may include air, a processing unit (e.g., a compressor or other type of processing unit) that outputs oxygen-enriched air or a fluid having an oxygen concentration within a preselected oxygen concentration range, or other oxygen sources.

[0021] In a twelfth aspect, the boiler may include a secondary oxidant conduit located near the periphery of the first pulverized coal entrained fluid flow conduit so that the secondary oxidant flow passes through the burner and enters the combustion chamber. The secondary oxidant may be provided by an oxidant source (e.g., air, a secondary air source, an air compressor, a processing unit that outputs an oxidant flow, etc.).

[0022] In a thirteenth aspect, the second pulverized coal entrained fluid flow conduit can be located near the periphery of the first pulverized coal entrained fluid flow conduit, so that the first pulverized coal entrained fluid flow conduit is between the second pulverized coal entrained fluid flow conduit and the hydrogen oxidant conduit. The secondary oxidant conduit can be located near the periphery of the second pulverized coal entrained fluid flow conduit so that the secondary oxidant flows through the burner and into the combustion chamber. The secondary oxidant can be provided by an oxidant source (e.g., air, a secondary air source, etc.). The pulverized coal source is connected to the inlet of the second pulverized coal entrained fluid flow conduit. The source can be the same source as the source used to supply pulverized coal to the first pulverized coal entrained fluid flow conduit, or can be a second independent pulverized coal source.

[0023] In the fourteenth aspect, the boiler may include a mixing conduit located in the portion of the first pulverized coal entrained fluid flow conduit, and the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit pass through the mixing conduit to be output from the burner (for example, the hydrogen and hydrogen oxidant may pass through the mixing conduit before being output from the burner). In such embodiments, a flow splitter may be optionally provided. The flow splitter may be positioned to surround the outer peripheral portion of the outlet region of the hydrogen oxidant flow conduit in the first pulverized coal entrained fluid flow conduit to split the first pulverized coal entrained fluid flow into a first inner flow portion and a second outer flow portion, the first inner flow portion being directed to the inlet of the mixing conduit to pass through the mixing conduit, and the second outer flow portion passing along the outside of the mixing conduit. The flow splitter may be attached to the mixing conduit to be integrated with the mixing conduit, or may be fastened, welded or bonded to the mixing conduit in other ways. In some embodiments, a splitter can be located between the first pulverized coal entraining fluid flow conduit and the hydrogen oxidant conduit, adjacent to the outlet of the hydrogen oxidant conduit, to divert the first inner flow portion along a channel defined between the splitter and the hydrogen oxidant conduit, thereby mixing the pulverized coal in the first inner portion with the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit in the mixing conduit.

[0024] In the fifteenth aspect, the boiler can be configured so that the outlet of the hydrogen oxidant conduit is a tapered outlet having a tapered portion, and a gap is defined between the outlet of the hydrogen oxidant conduit and the mixing conduit, so that the first part of the pulverized coal passing through the first pulverized coal entraining fluid flow conduit passes through the gap to mix with the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit in the mixing conduit, while the second part of the pulverized coal passing through the first pulverized coal entraining fluid flow conduit passes along the outside of the mixing conduit.

[0025] In the sixteenth aspect, the boiler can be arranged so that the outlet of the hydrogen oxidant conduit is an expanded outlet with an expanded portion. In such embodiments, the outlet of the hydrogen oxidant conduit can be an expanded outlet with an expanded portion (e.g., the outlet of the hydrogen oxidant conduit can be widened from a widened position until the distal end of the hydrogen oxidant outlet, so that the outlet is wider at the distal end than at the widened position upstream of the distal end of the outlet). A gap can be defined between the outlet of the hydrogen oxidant conduit and the mixing conduit so that the first part of the pulverized coal passing through the first pulverized coal entrained fluid flow conduit passes through the gap to mix with the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit in the mixing conduit, while the second part of the pulverized coal passing through the first pulverized coal entrained fluid flow conduit passes along the outside of the mixing conduit. This arrangement can cause the outermost part of the expanded outlet portion of the outlet of the hydrogen oxidant conduit to extend beyond the inlet of the mixing conduit. This may cause the enlarged outlet portion to protrude into the first pulverized coal entraining fluid flow conduit and may affect how a portion of the pulverized coal flow entrained in the fluid is transferred into the inlet of the mixing conduit and toward the outlet of the first pulverized coal entraining fluid flow conduit.

[0026] In the seventeenth aspect, the splitter can be located between the first pulverized coal entraining fluid flow conduit and the hydrogen oxidant conduit, adjacent to the outlet of the hydrogen oxidant conduit, to transfer a portion of the pulverized coal along a channel defined between the splitter and the hydrogen oxidant conduit, thereby mixing the portion of the pulverized coal with the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit in the mixing conduit.

[0027] In an eighteenth aspect, the boiler can be arranged such that a first pulverized coal entrained fluid flow conduit is positioned to receive a flow of pulverized coal entrained within a fluid including hydrogen. Hydrogen can be injected into the flow of pulverized coal entrained within the fluid prior to supplying the flow to the first pulverized coal entrained fluid flow conduit. As discussed above, a control valve can also be utilized to adjust the injection rate of hydrogen supplied to the flow.

[0028] In the nineteenth aspect, a method for generating a flame in a combustion chamber of a combustion device is provided. An embodiment of the method may utilize an aspect of the burner discussed above and other aspects of the burner discussed herein, or an aspect of the boiler discussed above and other aspects discussed herein. An embodiment of the method may include supplying hydrogen, a hydrogen oxidant flow, and a first pulverized coal entrained in the oxidant flow to the burner, so that the hydrogen passes through an inner hydrogen conduit of the burner, the hydrogen oxidant flow passes through a hydrogen oxidant conduit of the burner located between the first pulverized coal entrained fluid flow conduit and the inner hydrogen conduit, and the first pulverized coal entrained in the oxidant flow passes through the first pulverized coal entrained fluid flow conduit. The method may also include outputting hydrogen from the outlet of the inner hydrogen conduit, so that when the hydrogen is transferred from the outlet of the inner hydrogen conduit to the outlet of the hydrogen oxidant conduit, the hydrogen passes through a first distance, so that the hydrogen output from the outlet of the inner hydrogen conduit reaches the outlet of the hydrogen oxidant conduit through a portion of the hydrogen oxidant conduit. An embodiment of the method may additionally include outputting a hydrogen gas flow and a hydrogen oxidant flow from an outlet of the hydrogen oxidant conduit such that when the hydrogen is transferred from the outlet of the hydrogen oxidant conduit to the outlet of the first pulverized coal entrained fluid flow conduit, the hydrogen gas flow and the hydrogen oxidant flow pass through a second distance such that the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit pass through a portion of the first pulverized coal entrained fluid flow conduit, thereby forming an ignition flame emitted from the outlet of the burner.

[0029] In the twentieth aspect, the method may further include splitting a first portion of the first pulverized coal entrained in the oxidant stream from a second portion of the first pulverized coal entrained in the oxidant stream, such that the first portion of the first pulverized coal entrained in the oxidant stream mixes with the hydrogen gas stream and the hydrogen oxidant stream as the hydrogen gas stream and the hydrogen oxidant stream pass along a second distance in the burner to form an ignition flame, while the second portion of the first pulverized coal entrained in the oxidant stream passes through the first pulverized coal entraining fluid flow conduit to be output into the combustion chamber. For example, embodiments of the twentieth aspect may utilize embodiments including a mixing conduit and / or a flow splitter as discussed herein.

[0030] In the twenty-first aspect, the method may also include injecting hydrogen into the first pulverized coal entrained in the oxidant flow before the first pulverized coal entrained in the oxidant flow is supplied to the burner, so that the first pulverized coal entrained in the oxidant flow passing through the first pulverized coal entrained fluid flow conduit includes hydrogen, pulverized coal and oxidant.

[0031] In a twenty-second aspect, a burner for a combustion chamber is provided, the burner comprising a first pulverized coal entrained fluid flow conduit, an inner hydrogen conduit, and a hydrogen oxidant conduit located between the first pulverized coal entrained fluid flow conduit and the inner hydrogen conduit. A mixing conduit may be located in the first pulverized coal entrained fluid flow conduit, so that hydrogen output from an outlet of the inner hydrogen conduit and hydrogen oxidant output from an outlet of the hydrogen oxidant conduit can pass through the mixing conduit to mix with a first portion of the pulverized coal flow entrained in the fluid that can pass through the first pulverized coal entrained fluid flow conduit, thereby being output from the burner as a mixture surrounding a flame formed by combustion of hydrogen, hydrogen oxidant, and a portion of the pulverized coal within the first portion of the pulverized coal flow entrained in the fluid. The mixing conduit can be located in the first pulverized coal entrained fluid flow conduit, so that the second part of the pulverized coal flow entrained in the fluid passing through the first pulverized coal entrained fluid flow conduit can be separated from the first part of the pulverized coal flow entrained in the fluid via the mixing conduit, so that the second part is discharged from the burner together with the flame and the unburned part of the mixture of hydrogen, hydrogen oxidant and the first part of the pulverized coal flow entrained in the fluid.

[0032] In a twenty-third aspect, embodiments of the burner may include a secondary oxidant conduit located near the periphery of the first pulverized coal entraining fluid flow conduit to allow the secondary oxidant flow to pass through the burner and into the combustion chamber. The outlet of the inner hydrogen conduit may be located at an axial distance X relative to the outlet of the hydrogen oxidant conduit. H2 and the inner hydrogen conduit may have a diameter D H2 , and there is a gap having a gap distance between the inlet of the mixing conduit and the outlet of the hydrogen oxidant conduit, the gap separating the inlet of the mixing conduit from the outlet of the hydrogen oxidant conduit, wherein:

[0033] (i) -1≤X H2 / D H2 ≤5, and / or

[0034] (ii)0.05≤((2*dg*r1) / (r4 2 -r1 2 ))≤0.15;

[0035] Where dg is the gap distance, r1 is the radius of the inner hydrogen conduit, r2 is the radius of the hydrogen oxidant conduit, r3 is the radius of the first pulverized coal entraining fluid flow conduit, and r4 is the radius of the secondary oxidant conduit.

[0036] In such embodiments, the outlet of the hydrogen oxidant conduit can be an expanded outlet with an expanded portion (e.g., the outlet of the hydrogen oxidant conduit can be widened from a widened position until the distal end of the hydrogen oxidant outlet, so that the outlet is wider at the distal end than at the widened position upstream of the distal end of the outlet). This arrangement can cause the outermost portion of the expanded outlet portion of the outlet of the hydrogen oxidant conduit to extend beyond the inlet of the mixing conduit. This can cause the expanded outlet portion to protrude into the first pulverized coal entrained fluid flow conduit, and can affect how a portion of the pulverized coal flow entrained in the fluid is transferred to the inlet of the mixing conduit and toward the outlet of the first pulverized coal entrained fluid flow conduit. The gap defined between the outlet of the hydrogen oxidant conduit and the mixing conduit can be configured so that a first portion of the pulverized coal passing through the first pulverized coal entrained fluid flow conduit passes through the gap to mix with hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit in the mixing conduit, while a second portion of the pulverized coal passing through the first pulverized coal entrained fluid flow conduit passes along the outside of the mixing conduit. The second portion of the pulverized coal entraining fluid flow may include coal of a larger particle size than the first portion of the pulverized coal entraining fluid flow that passes through the gap to be delivered into the mixing conduit.

[0037] In the twenty-fourth aspect, the axial distance XH2 may be the axial distance between the outlet of the hydrogen oxidant conduit and the inlet of the mixing conduit.

[0038] In the twenty-fifth aspect, the axial distance XH2 can be less than 0, so that the outlet of the inner hydrogen conduit is located at a first distance from the outlet of the hydrogen oxidant conduit, so that the hydrogen output from the outlet of the inner hydrogen conduit passes through a portion of the hydrogen oxidant conduit to reach the outlet of the hydrogen oxidant conduit.

[0039] In the twenty-sixth aspect, the axial distance XH2 can be 0, so that the outlet of the inner hydrogen conduit coincides with the outlet of the hydrogen oxidant conduit.

[0040] In the twenty-seventh aspect, the axial distance XH2 can be greater than 0, such that the outlet of the inner hydrogen conduit is located within the mixing conduit.

[0041] In the twenty-eighth aspect, an embodiment of the burner may include a secondary oxidant conduit located near the periphery of the first pulverized coal entrained fluid flow conduit so that the secondary oxidant flow passes through the burner and enters the combustion chamber. The burner may also include a mixing conduit located in the portion of the first pulverized coal entrained fluid flow conduit, and the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit pass through the mixing conduit to be output from the burner (for example, the hydrogen and hydrogen oxidant may pass through the mixing conduit before being output from the burner). The outlet of the inner hydrogen conduit may be spaced apart from the outlet of the hydrogen oxidant conduit by an axial length LH2. The inner hydrogen conduit may also have a diameter DH2. The inlet of the mixing conduit may be spaced apart from the inlet distance Gc from the tapered position of the outlet of the hydrogen oxidant conduit, and the hydrogen oxidant conduit begins to taper at the tapered position until the outlet of the hydrogen oxidant conduit. In addition, the burner may be arranged and configured such that:

[0042] (i)1≤L H2 / D H2 ≤5, and / or

[0043] (ii)0.05≤((2*G c *r1) / (r4 2 -r1 2 ))≤0.15;

[0044] Where r1 is the radius of the inner hydrogen conduit, r2 is the radius of the hydrogen oxidant conduit, r3 is the radius of the first pulverized coal entraining fluid flow conduit, and r4 is the radius of the secondary oxidant conduit.

[0045] The twenty-eighth aspect can be used in combination with the aspects discussed above (eg, the first to fourth aspects, the tenth to fourteenth aspects, etc.).

[0046] In the twenty-ninth aspect, the inlet distance Gc may be the axial length of the gap between the inlet of the mixing conduit and the tapered position of the hydrogen oxidant conduit.

[0047] In the thirtieth aspect, the burner may include a secondary oxidant conduit and a mixing conduit, the secondary oxidant conduit being located near the periphery of the first pulverized coal entrained fluid flow conduit so that the secondary oxidant flows through the burner and into the combustion chamber, the mixing conduit being located in the portion of the first pulverized coal entrained fluid flow conduit, the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit passing through the mixing conduit to be output from the burner (e.g., the hydrogen and hydrogen oxidant may pass through the mixing conduit before being output from the burner). The inlet of the mixing conduit may be spaced apart from the outlet of the hydrogen oxidant conduit by a gap having a gap distance. The outlet of the inner hydrogen conduit may have an axial distance XH2 relative to the outlet of the hydrogen oxidant conduit. The inner hydrogen conduit may also have a diameter DH2. The inlet of the mixing conduit may be spaced apart from the outlet of the hydrogen oxidant conduit by a gap distance, and wherein:

[0048] (i) -1≤X H2 / D H2 ≤5, and / or

[0049] (ii)0.05≤((2*dg*r1) / (r4 2 -r1 2 ))≤0.15;

[0050] Where dg is the gap distance, r1 is the radius of the inner hydrogen conduit, r2 is the radius of the hydrogen oxidant conduit, r3 is the radius of the first pulverized coal entraining fluid flow conduit, and r4 is the radius of the secondary oxidant conduit.

[0051] In the thirty-first aspect, the gap distance dg can be the axial distance between the outlet of the hydrogen oxidant conduit and the inlet of the mixing conduit.

[0052] In the thirty-second aspect, 32. A mixing conduit may be located in the portion of the first pulverized coal entrained fluid flow conduit, and the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit pass through the mixing conduit to be output from the burner (for example, the hydrogen and hydrogen oxidant may pass through the mixing conduit before being output from the burner). The inlet of the mixing conduit may be spaced apart from the outlet of the hydrogen oxidant conduit by a gap having a gap distance. The flow splitter may be positioned to surround the outer peripheral portion of the outlet region of the hydrogen oxidant flow conduit in the first pulverized coal entrained fluid flow conduit to split the first pulverized coal entrained fluid flow into a first inner flow portion and a second outer flow portion, the first inner flow portion being guided to the inlet of the mixing conduit to pass through the mixing conduit, and the second outer flow portion passing along the outside of the mixing conduit. The outlet of the inner hydrogen conduit may be spaced apart from the outlet of the hydrogen oxidant conduit by an axial length LH2, and the inner hydrogen conduit may also have a diameter DH2. The inlet of the mixing conduit may be spaced apart from the outlet of the hydrogen oxidant conduit by a gap distance. In addition, the burner may be arranged such that:

[0053] (i)1≤L H2 / D H2 ≤5, and

[0054] (ii)0.05≤((r6 2 -r5 2 ) / (r8 2 -r7 2 ))≤0.25;

[0055] Wherein r5 is the outer radius of the hydrogen conduit, r6 is the inner radius of the splitter, r7 is the outer radius of the splitter, and r8 is the inner radius of the first pulverized coal entraining fluid flow conduit.

[0056] In the thirty-third aspect, a flow divider may be located between the first pulverized coal entrained fluid flow conduit and the hydrogen oxidant conduit, adjacent to the outlet of the hydrogen oxidant conduit, to divert the first inner flow portion along a passage defined between the flow divider and the hydrogen oxidant conduit, thereby mixing the pulverized coal of the first inner portion with the hydrogen and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit in the mixing conduit.

[0057] In the thirty-fourth aspect, the boiler may include at least one burner positioned to generate at least one flame in the combustion chamber. The at least one burner may include a first burner configured as a burner of any of the above aspects. For example, the first burner may be a burner of the twenty-second aspect. Other embodiments of the boiler may have a first burner including other features of aspects twenty-second to thirty-third, may be a burner of the first aspect, or may be a burner including features of the first aspect and features from one or more of aspects two to seventeen.

[0058] In some embodiments, the boiler may include a pulverized coal source connected to an inlet of the first pulverized coal entrained fluid flow conduit, a hydrogen source connected to an inlet of the internal hydrogen conduit, and an oxidant stream source connected to an inlet of the hydrogen oxidant conduit. In some embodiments of the boiler, a hydrogen source positioned to inject hydrogen into the pulverized coal stream entrained within the fluid may also be provided, such that the first pulverized coal entrained fluid flow conduit is positioned to receive the pulverized coal stream entrained within the fluid, such that the fluid includes the oxidant and hydrogen from the hydrogen source.

[0059] It should be understood that different embodiments may utilize one or more of the first to thirty-fourth aspects to create additional embodiments having different combinations of these aspects for use in embodiments of a burner, a boiler, a combustion apparatus, a method for operating at least one burner, a method for operating a boiler, or a method for operating a burner.

[0060] The aspects discussed above can be configured and arranged so that there is a gap distance dg, a radius r1 as the radius of the inner hydrogen conduit, a radius r2 as the radius of the hydrogen oxidant conduit, a radius r3 as the radius of the first pulverized coal entrained fluid flow conduit, and a radius r4 as the radius of the secondary oxidant conduit. In such a configuration, the radius of each conduit can be the distance of the inner side of the outer wall of the conduit from the central axis of the hydrogen conduit or the central axis of the burner. The inner side of the outer wall of each conduit can be a side of the outer wall of the conduit, and a portion of the fluid and / or particles flowing through the conduit can be directly contacted along this side when it flows through the conduit. For example, the central axis can be a central axis extending linearly in an axial direction perpendicular to the burner plane or substantially perpendicular to the burner plane (for example, within a range of 5° vertical or within a range of 7° vertical, etc.). The first radius r1 can be a linear measurement distance between the central axis and the inner side of the outer wall of the hydrogen conduit. The second radius r2 can be a linear measurement distance between the central axis and the inner side of the outer wall of the hydrogen oxidant conduit. The third radius r3 can be a linear measurement distance between the central axis and the inner side of the outer wall of the first pulverized coal entrained fluid flow conduit. The fourth radius r4 may be a linear measurement distance between the central axis and the inside of the outer wall of the secondary oxidant conduit. The gap distance dg may be a linear measurement distance between the outlet of the hydrogen oxidant conduit and the inlet of the mixing conduit (e.g., the axial distance between the inlet of the mixing conduit and the outlet of the hydrogen oxidant conduit, which separates the outlet of the hydrogen oxidant conduit from the inlet of the mixing conduit).

[0061] Some aspects discussed above may be configured and arranged such that there is a radius r5 as the outer radius of the hydrogen conduit, a radius r6 as the inner radius of the diverter, a radius r7 as the outer radius of the diverter, and a radius r8 as the inner radius of the first pulverized coal entrained fluid flow conduit. Each radius r5-r8 may be the distance of a portion of the conduit or diverter from the central axis of the hydrogen conduit or the central axis of the burner. As discussed above, the central axis may be a central axis extending linearly in an axial direction perpendicular to the burner plane or substantially perpendicular to the burner plane (e.g., within a range of 5° vertical or within a range of 7° vertical, etc.). In such a configuration, the radius r5 may be the linear measurement distance of the inner side of the outer wall of the hydrogen oxidant conduit from the central axis (the radius r5 may also be considered as the radius of the hydrogen oxidant conduit (similar to the radius r2 discussed above). The radius r6 may be the linear measurement distance between the central axis and the inner side of the diverter. The radius r7 may be the linear measurement distance between the outer side of the diverter and the central axis. The radius r8 may be the linear measurement distance between the inner side of the outer wall of the first pulverized coal entrained fluid flow conduit and the central axis.

[0062] The ratio (r62-r521) / (r82-r72)) can be considered as the ratio of the cross-sectional area Ar. The ratio Ar can be the ratio of the cross-sectional area between the inner coal flow channel and the outer coal flow channel separated by the splitter, and the ratio can be assumed to be equal to the ratio of the first inner flow portion and the second outer flow portion of the first pulverized coal entraining fluid flow formed via the splitter.

[0063] The axial distance XH2 and the axial length LH2 are discussed above. The axial distance XH2 may be a linear extension distance measured along the central axis of the burner or hydrogen conduit between two locations (e.g., the outlet of the hydrogen conduit and the outlet of the hydrogen oxidant conduit). The axial length LH2 may be a linear extension distance measured along the central axis of the burner or hydrogen conduit between two locations (e.g., the outlet of the hydrogen conduit and the outlet of the hydrogen oxidant conduit).

[0064] Other details, objects and advantages of boilers, burners, burners, methods for operating burners, methods for operating boilers and / or burners, and methods of making and using the same will become apparent as the following description of certain exemplary embodiments thereof proceeds. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Exemplary embodiments of boilers, burners, burners, methods for operating burners, methods for operating boilers and / or burners, and methods of making and using the same are shown in the drawings included herein. It should be understood that like reference symbols used in the drawings may identify like components.

[0066] Figure 1 is a schematic diagram of a first exemplary embodiment of a boiler 1 having a burner therein, the boiler comprising one or more burner nozzles 5 configured to output one or more flames 4 into a combustion chamber 3 of the boiler 1 .

[0067] Figure 2 is a schematic cross-sectional view of a first exemplary embodiment of a burner 5 that may be utilized in a first exemplary embodiment of a boiler.

[0068] Figure 3 is a schematic partial view of a burner outlet region of a first exemplary embodiment of a burner.

[0069] Figure 4 is a schematic partial view of a burner outlet region of a first exemplary embodiment of a burner for generating at least one flame in a combustion chamber 3 of a burner of a boiler 1 .

[0070] Figure 5 is similar to Figure 30026] FIG1 is a schematic partial view of a burner outlet region of a first exemplary embodiment of a burner of FIG1 and illustrates an exemplary swirler shown in phantom that may be included in the burner.

[0071] Figure 6 It can be similar to Figure 2 A schematic diagram of a first exemplary embodiment of a burner utilized in a first exemplary embodiment of a boiler of the type shown in FIG. 1 includes a schematic diagram of a feed stream supplied to the burner. A hydrogen feed for including hydrogen into a pulverized coal stream mixed with a primary air stream (e.g., air, a primary oxidant stream for mixing with solid particles of pulverized coal, etc.) is shown in dashed lines.

[0072] Figure 7 is a schematic cross-sectional view of a second exemplary embodiment of a burner 5 that may be utilized in the first exemplary embodiment of the boiler.

[0073] Figure 8 is a schematic partial view of a burner outlet region of a second exemplary embodiment of a burner 5 for generating at least one flame in a combustion chamber 3 of a burner of a boiler 1 .

[0074] Fig. 9 is similar to Figure 8 Schematic partial view of the burner outlet region of a second exemplary embodiment of a burner 5 .

[0075] Fig.10 is a schematic cross-sectional view of a third exemplary embodiment of a burner 5 that may be utilized in the first exemplary embodiment of the boiler.

[0076] Fig.11 is a schematic partial view of the burner outlet region of a third exemplary embodiment of a burner 5 for generating at least one flame in the combustion chamber 3 of a burner of a boiler 1, wherein a hydrogen duct 10 is extended so that its outlet 10o is in the same position as the outlet 11o of an internal hydrogen oxidant duct 11.

[0077] Fig.12 is similar to Fig.11 Schematic partial view of the burner outlet region of a third exemplary embodiment of a burner 5 .

[0078] Fig.13 is similar to Fig.11 and 12 Schematic partial view of the burner outlet region of a third exemplary embodiment of a burner 5 , illustrating an exemplary arrangement in which the hydrogen conduit 10 extends beyond the outlet 11o of the inner hydrogen oxidant conduit 11 to a position within the mixing conduit 31 .

[0079] Fig.14 is similar to Fig.11 , 12 13 and 14 are schematic partial views of the burner outlet region of a third exemplary embodiment of the burner 5, illustrating an exemplary arrangement in which the hydrogen conduit 10 is located within the inner hydrogen oxidant conduit 11 such that the outlet 11o of the inner hydrogen oxidant conduit 11 is located between the inlet 31i of the mixing conduit 31 and the outlet 10o of the hydrogen conduit 10.

[0080] Fig.15 is a schematic partial view of a burner outlet region of a fourth exemplary embodiment of a burner.

[0081] Fig.16 is similar to Fig.15 Schematic partial view of the burner outlet region of a fourth exemplary embodiment of a burner.

[0082] Fig.17 is a schematic diagram of a fifth exemplary embodiment of a burner that can be utilized in the first exemplary embodiment of the boiler, including a schematic diagram of a feed stream supplied to the burner. A hydrogen feed for including hydrogen into a pulverized coal stream mixed with a primary air stream (e.g., air, a primary oxidant stream for mixing with solid particles of pulverized coal, etc.) is shown in dashed lines.

[0083] Fig.18 is a schematic partial view of a burner outlet region of a fifth exemplary embodiment of a burner.

[0084] Fig.19 is a flow chart illustrating an exemplary method for generating at least one flame in combustion chamber 3 .

[0085] Fig. 20 is a graph illustrating test results of tests performed on an exemplary embodiment of a burner using an exemplary embodiment of the method for generating at least one flame in a combustion chamber 3 .

[0086] Fig.21 is a table illustrating test results of tests performed on an exemplary embodiment of a burner using an exemplary embodiment of the method for generating at least one flame in a combustion chamber 3 . DETAILED DESCRIPTION

[0087] refer to Figures 1 to 19, the boiler 1 may include a burner having a combustion chamber 3. Fuel may be supplied to the combustion chamber via at least one burner 5 (e.g., a single burner 5, a plurality of burners 5, etc.) and burned therein. Each burner 5 may be connected to a wind box 2, which may be connected to the boiler 1 or included in the boiler 1. One or more burners 5 may be connected to the wind box 2 to receive secondary air or another type of secondary oxidant stream (e.g., air, oxygen-enriched air, other oxygen-containing fluid streams), thereby outputting a secondary oxidant stream having fuel and at least one primary oxidant stream included together with the fuel. In some configurations, the wind box 2 may also be arranged to provide one or more other oxidant streams to the burner 5. Other oxidant stream sources that may be connected to the burner 5 may also be present.

[0088] Each burner 5 can be configured to output one or more burner streams from the outlet 5a of the burner to burn at least one fuel, thereby generating at least one flame 4 in the combustion chamber 3. The generated flame 4 formed in the combustion chamber 3 can cause the hot gas including the combustion product to be transferred out of the combustion chamber and transferred to the flue 8 or other conduit of the boiler 3 for heating water to form steam and / or heating another fluid. The steam or other heated fluid formed can be supplied to other processing units. For example, the steam formed can be supplied to at least one turbine for power generation, and the other heated fluids can be utilized in other plant units (e.g., using hot fluids in heat exchangers, etc.).

[0089] The combustion gas may be output from the boiler output 8a as at least one flue gas stream. The flue gas output from the boiler 1 may be supplied to other downstream processing units (e.g., heat exchangers, scrubbers, filtration units, carbon capture units, etc.) to use the output fluid in other plant processes and / or fluid treatments, thereby discharging the output stream as an exhaust stream to the atmosphere.

[0090] The boiler 1 may utilize a plurality of different burners or a single burner 5. When utilizing a plurality of burners 5, the burner array may be positioned at different locations, or may be positioned in aligned locations to meet a set of specific preselected design criteria, thereby helping to promote a desired combustion process or temperature distribution within the combustion chamber. Each burner 5 may be an embodiment of the burners discussed herein. In some implementations, one or more burners may all utilize the same configuration (e.g., Figures 2 to 6 , 7 to 9, 17 to 18, or other embodiments discussed herein). In other specific implementations, the burner 5 can have a different configuration (for example, one or more burners can be Figures 2 to 6 In one embodiment, one or more other burners may be Figures 7 to 9 In one embodiment, one or more other burners may be Figures 10 to 14embodiments, and / or one or more burners may be Figures 17 to 18 implementation plans, etc.).

[0091] Each burner 5 may have a burner outlet 5a. The flame 4 may be generated and discharged from the outlet 5a via a burner plane 5p of the burner 5. For example, the burner plane 5p may be adjacent to a wall of the combustion chamber 3 where the burner is mounted.

[0092] If available from Figures 2 to 18 As best understood, each burner 5 may have a specific structure to facilitate the supply of both hydrogen and pulverized coal into the combustion chamber 3 for combustion of the fuel, thereby forming at least one flame 4 and generating hot gases including combustion products resulting from the combustion of the fuel and the formation of the flame 4. The burner 5 may be configured to utilize at least one hydrogen stream to assist in igniting the pulverized coal at boiler startup to assist in flame generation, thereby forming a flame 4 having, for example, improved stability, reduced nitrogen oxide (NOx) formation, helping to minimize particulate formation from fuel combustion, and overall improved performance. Hydrogen may also be utilized to assist in providing improved flame stability, helping to maintain low NOx formation, reducing particulate and CO2 emissions, and also providing improved operating performance after boiler startup when the boiler is operating under steady-state conditions or other non-startup conditions.

[0093] For example, improved start-up of the flame 4 can be performed with reduced particulate and CO2 emissions formed during the fuel combustion process, which is used to start the fuel combustion in the combustion chamber 3 to form one or more flames 4 therein and generate flue gases including combustion products. The combustion gases formed can include significantly fewer particles compared to conventional boilers that can use diesel fuel or oil fuel as secondary fuel. The embodiment of the burner can be modified so that hydrogen can also be supplied via the burner 5 during steady-state operation of the boiler to help provide improved flame stability and reduce particulates formed during the combustion process.

[0094] Utilizing hydrogen as a secondary fuel for the burner can be configured to extend the turndown operation of the boiler 1 and improve the load following capability of the boiler 1. For example, embodiments can provide a turndown ratio of 10:1 or greater. It can also help facilitate emissions improvements by reducing NOx formation and NOx emissions and reducing particulate and CO2 emissions. In addition, embodiments can provide a highly durable burner that can be manufactured at a relatively low capital cost while requiring little, if any, routine maintenance, which can also help improve the operating performance of the boiler 1 and / or the burner 5.

[0095] Embodiments of the burner 5 may include a burner outlet 5a that may discharge a hydrogen gas stream having a hydrogen (or H2) concentration of at least 30 volume percent (vol%), a primary hydrogen oxidant stream having an oxygen (or O2) concentration greater than or equal to the oxygen concentration typically present in air (approximately 20.8 vol%) and preferably between approximately 20.8 vol% and 50 vol%, and at least one pulverized coal mixture stream (e.g., solid particles of coal) entrained in a coal transport fluid (e.g., air, nitrogen, air mixed with nitrogen, carbon dioxide, oxygen-enriched air, air mixed with hydrogen, oxygen-enriched air mixed with hydrogen, etc.), wherein the ratio of coal to coal oxidant in the transport fluid is in the range of approximately 0.1 lb. to 10 lb. of coal per pound (lb.) of coal oxidant fluid. At least one secondary oxidant stream (e.g., air, oxygen-enriched air, etc.) may also be output from the burner outlet 5a.

[0096] At a concentration of 0.1 lb. coal per lb. coal oxidant fluid, which may be output from the burner 5, the coal oxidant may be considered a lean mixture, which may be more difficult to ignite. In contrast, a concentration of 10 lb. coal per lb. coal oxidant fluid may be considered a thick mixture, which may be more difficult to transport pneumatically at lower dilution levels.

[0097] The secondary oxidant flow 21f can be a secondary air flow (most preferably), an oxygen-enriched air flow, or other oxygen-containing oxidant flow of a gaseous fluid, which can be supplied to the secondary oxidant conduit 21 to be discharged from the outlet 21o of the secondary oxidant conduit 21. In some embodiments, the secondary oxidant flow can be an air flow provided by a blower or a compressor (not shown), which can compress the air flow to be supplied toward one or more burners 5 and / or to the wind box 2.

[0098] There may be one or more swirlers 21s located in the secondary oxidant conduit 21. Each swirler 21s may be a body located in or adjacent to the conduit, so that the secondary oxidant flow 21f swirls around or around the central axis or longitudinal axis of the burner due to passing along the body of the swirler 21s, so that the output of the secondary oxidant flow swirls in the combustion chamber 3 after being discharged from the outlet 21o of the secondary oxidant conduit 21 located at the outlet 5a of the burner 5 or adjacent to the outlet.

[0099] The secondary oxidant conduit 21 may be an annular conduit positioned to surround at least one pulverized coal entraining fluid flow conduit (e.g., the first pulverized coal entraining fluid flow conduit 19). Fig.17 and 18 As shown in the exemplary embodiment of FIG. 1 , the secondary oxidant conduit 21 may be located around the outer periphery of the second pulverized coal entraining fluid flow conduit 29. As another example, as Figures 2 to 16As shown in the embodiment of FIG. 1 , the secondary oxidant conduit 21 may be located around the periphery of the first pulverized coal entraining fluid flow conduit 19 .

[0100] The first pulverized coal entraining fluid flow conduit 19 may include an inlet 19i at which pulverized coal mixed with air or other transport fluid (e.g., oxygen-enriched air, etc.) may be supplied to the first pulverized coal entraining fluid flow conduit 19, so that a first flow 19f of the mixture of pulverized coal and the transport fluid (e.g., coal particles entrained in air, oxygen-enriched air, other oxidant fluid stream, etc.) may pass through the first pulverized coal entraining fluid flow conduit 19 to be discharged at the outlet 5a of the burner 5. The first pulverized coal entraining fluid flow conduit 19 may also have an outlet 19o adjacent to the outlet 5a of the burner, through which at least a portion of the first flow 19f of the mixture of pulverized coal and the transport fluid may be output from the first pulverized coal entraining fluid flow conduit 19. For example, the outlet 19o may be located at the terminal outlet 5a of the burner 5. In some embodiments, the first pulverized coal flow entrained in the gaseous transport fluid passing through the first pulverized coal entraining fluid flow conduit 19 may also include hydrogen mixed therein (see, e.g., Figure 6 and 12 H2 hybrid option shown in ).

[0101] The first pulverized coal entraining fluid flow conduit 19 may be an annular conduit positioned to surround the inner hydrogen conduit 10 and the inner hydrogen oxidant conduit 11. For example, Figures 2 to 18 As shown in the exemplary embodiment of FIG. 1 , the first pulverized coal entraining fluid flow conduit 19 may be located around the outer circumference of the inner hydrogen oxidant conduit 11 .

[0102] like Figures 2 to 18 As shown in the exemplary embodiment of FIG. 1 , the hydrogen conduit 10 may be located within the inner hydrogen oxidant conduit 11, such that the inner hydrogen oxidant conduit 11 is located around the outer periphery of the inner hydrogen conduit 10. In such an embodiment, the inner hydrogen oxidant conduit 11 may be located between the hydrogen conduit 10 and the first pulverized coal entrained fluid flow conduit 19. The hydrogen conduit 10 may be the innermost conduit of the burner 5, or the inner center conduit of the burner 5.

[0103] In embodiments utilizing a second pulverized coal entraining fluid flow conduit 29 (e.g., Figures 17 to 18 In embodiments such as those of the present invention, the second pulverized coal entraining fluid flow conduit 29 may be located between the first pulverized coal entraining fluid flow conduit 19 and the secondary oxidant conduit 21. In embodiments that do not utilize the second pulverized coal entraining fluid flow conduit 29 (e.g., Figures 1 to 11 In the embodiment of the present invention, the first pulverized coal entraining fluid flow conduit 19 can be located between the inner hydrogen oxidant conduit 11 and the secondary oxidant conduit 21.

[0104] The secondary oxidant conduit 21 may be the outermost conduit, through which an oxygen-containing fluid (e.g., a gaseous air flow, an oxygen-enriched gaseous air flow, etc.) passes through the burner 5 as a secondary oxidant flow 21f to be supplied to the combustion chamber 3 via the outlet 5a of the burner 5. The hydrogen conduit 10 may be the central conduit or the innermost conduit, through which a hydrogen fluid flow passes through the burner as a hydrogen flow 10f, which is transferred from the inlet 10i of the hydrogen conduit 10 to the outlet 10o to be supplied to the combustion chamber 3 via the outlet 5a of the burner 5. Other conduits of the burner 5 may be considered as intermediate conduits located between the hydrogen conduit 10 and the secondary oxidant conduit 21.

[0105] The various conduits may be of different sizes and have different spacings relative to each other. For example, the hydrogen conduit 10 may have a radius r1 and a diameter DH2. The inner hydrogen oxidant conduit 11 may have a radius r2, the first pulverized coal entrained fluid flow conduit 19 may have a radius r3, and the secondary oxidant conduit 21 may have a radius r4. The second pulverized coal entrained fluid flow conduit 29 may also have a radius. The radius of each conduit may be the distance from the inner side of the outer wall of the conduit to the central axis 10ca of the hydrogen conduit 10 (e.g., at Fig. 9 The inner side of the outer wall of each conduit may be a side of the outer wall of the conduit along which a portion of the fluid and / or particles flowing through the conduit may directly contact as it flows through the conduit. For example, the central axis 10ca may be a central axis of the burner extending linearly in an axial direction perpendicular to the burner plane 5p or substantially perpendicular to the burner plane 5p (e.g., within 5° of the vertical or within 7° of the vertical, etc.).

[0106] The inner hydrogen oxidant conduit 11 can receive a hydrogen oxidant stream 11f at its inlet 11i and output the hydrogen oxidant stream 11f at its outlet 11o, so that the hydrogen oxidant stream 11f passes through the burner 5 via the inner hydrogen oxidant conduit 11. The hydrogen oxidant stream 11f can be received at the inlet 11f via the wind box 2 or via an independent hydrogen oxidant supply source that can supply the hydrogen oxidant stream 11f to the inner hydrogen oxidant conduit 11. The independent hydrogen oxidant supply source can be an independent blower or compressor, a liquid oxygen supply container, or a combination of such oxidant sources that are fluidly connected to the inlet 11i of the hydrogen oxidant conduit 11. For example, the hydrogen oxidant stream 11f supplied to the inner hydrogen oxidant conduit 11 can be a part of the compressed air received from the compressor, or can be an oxygen-enriched air stream. In some embodiments, at least one swirler 11f may be located near the outlet 11o of the inner hydrogen oxidant conduit 11, so that the oxidant flow passing through the inner hydrogen oxidant conduit swirls around the longitudinal axis of the burner by passing along the swirler 11s, so that the hydrogen oxidant flow 11f output from the outlet swirls in the combustion chamber 3. Preferably, the swirling flow of the hydrogen oxidant swirls in the same direction as the secondary oxidant output from the secondary oxidant conduit 21.

[0107] The hydrogen conduit 10 may receive a hydrogen fluid stream (e.g., hydrogen) at its inlet 10i to be output into the combustor 3 via the outlet 10o of the hydrogen conduit 10 and the outlet 5a of the burner, such that a hydrogen gas stream 10f passes through the burner 5 via the hydrogen conduit 10. The hydrogen gas stream 10f may be received from a container containing hydrogen gas, or may be received from another plant processing element that may output a hydrogen gas stream.

[0108] The hydrogen conduit 10 and the hydrogen oxidant conduit 11 can be positioned so that a pilot flame 4h can be formed when the hydrogen and oxidant flows output from the outlets 11o and 10o are transferred into the combustion chamber 3. The pilot flame 4h can be generated as an inner flame adjacent to the burner outlet 5a to facilitate the ignition and combustion of the coal output from the first pulverized coal entrainment fluid flow conduit 19 and the second pulverized coal entrainment fluid flow conduit 29 (when present), thereby forming a flame 4 in the combustion chamber. The formed flame 4 can be emitted outward from the pilot flame 4h in the combustion chamber 3. For example, in some cases, the formed flame can surround or surround the pilot flame 4h in the combustion chamber. The secondary oxidant conduit 21 can output an additional oxidant flow to help further facilitate the combustion of coal and hydrogen in the combustion chamber and the generation of a stable flame 4, and help define a central recirculation area 3a in the combustion chamber 3.

[0109] In some embodiments, at least one swirler 10s may be located near the outlet 10o of the inner hydrogen conduit 10, so that the hydrogen gas flow 10f (e.g., hydrogen or H2 gas flow, gas flow including hydrogen, H2, etc.) passing through the hydrogen conduit 10 is swirled by passing along the swirler 10s, so that the hydrogen gas flow 10f output from the outlet 10o is swirled in the combustion chamber 3. It should be understood that the embodiments of the burner 5 may not utilize the swirlers 10s and 11s in the hydrogen conduit 10 and the inner hydrogen oxidant conduit 11, utilize the swirlers 10s and 11s in the hydrogen conduit 10 and the inner hydrogen oxidant conduit 11, or utilize only the swirler 10s in the hydrogen conduit 10, or utilize only the swirler 11s in the inner hydrogen oxidant conduit 11. The use of these swirlers 10s, 11s may be combined with the swirlers in other conduits (e.g., the secondary oxidant conduit 21). The non-use of these cyclones 11s, 10s may also be used in embodiments in which one or more cyclones 21s are included in the secondary oxidant conduit 21.

[0110] When in some embodiments (e.g., Figures 17 to 18 When utilized in the embodiment of the present invention, the second pulverized coal entrained fluid flow conduit 29 can receive the second pulverized coal flow entrained in the transport fluid 29f at its inlet 29i, so that the second pulverized coal flow 29f entrained in the gaseous oxidant passes through the burner 5 via the second pulverized coal entrained fluid flow conduit 29 to be output via the outlet 29o of the second pulverized coal entrained fluid flow conduit 29. In some embodiments, the second pulverized coal flow entrained in the transport fluid 29f may also include hydrogen. Examples of the transport fluid of the second pulverized coal flow 29f entrained in the transport fluid may include a gaseous oxidant (e.g., air, oxygen-enriched air, oxygen-enriched flue gas, etc.) or a non-oxidant-containing gas flow (e.g., nitrogen, carbon dioxide, a mixture of nitrogen and carbon dioxide gases, etc.).

[0111] If available from Figures 2 to 6 As best understood, embodiments of the burner 5 may have an outlet 5a configured such that a hydrogen gas stream 10f output from the hydrogen conduit 10 passes along a first distance d1 to pass from the outlet 10o of the hydrogen conduit to reach the outlet 11o of the inner hydrogen oxidant conduit 11, which may permit the hydrogen to begin mixing with the oxidant stream output from the hydrogen oxidant conduit 11. After passing the first distance d1, these streams 10f, 11f may pass out the outlet 11o of the hydrogen oxidant conduit 11 and travel a second distance d2 to reach the outlet 19o of the first pulverized coal entraining fluid flow conduit 19. The second distance d2 may be preselected to permit a preselected amount of mixing between the hydrogen gas stream and the hydrogen oxidant stream and the coal stream entrained with the primary oxidant stream of the first stream 19f of a mixture of pulverized coal and transport fluid passing through the first pulverized coal entraining fluid flow conduit 19 toward the outlet 19o of the conduit.

[0112] Along this second distance d2, the streams of coal, hydrogen, and oxidant may interface with each other and mix. The presence of the cyclones 11s and 10s may facilitate such mixing, which may occur as these streams pass along the first distance d1 and the second distance d2. Figure 4 As best seen, the pilot flame 4h may be formed due to the mixing of the hydrogen flow and the hydrogen oxidant flow, which may be initiated during the travel of these flows along the first distance d1.

[0113] The initiation of ignition of the pilot flame 4h may occur at the exit plane of the inner hydrogen conduit 10 (e.g., at the exit 10o). The first distance d1 may be sized and configured to allow the pilot flame 4h to partially develop so that it becomes hotter and more chemically active before contacting the pulverized coal stream, which initially occurs at the exit plane of the inner hydrogen oxidant conduit 11 (e.g., at the exit 11o). The first distance d1 and the second distance d2 may be defined and configured to avoid being too long, thereby avoiding overheating of the conduit wall while still facilitating improved flame development.

[0114] The pilot flame 4h can help heat the solid coal particles cp in the first flow 19f of the mixture of pulverized coal and transport fluid, so that some of these particles are ignited as ignited coal particles icp to start forming a larger flame 4 that can be emitted from the pilot flame 4h. When these flows pass through the combustion chamber 3, these flows can be mixed with the secondary oxidant flow 21f output from the outlet 21o of the secondary oxidant conduit 21. The generated flame 4 and the output of these flows can define a recirculation area 3a in the combustion chamber 3. The recirculation area 3a can facilitate the further combustion of the coal particles cp in the combustion chamber 3 to stably generate a flame 4 defined by the pilot flame 4h and the ignited coal particles icp burning around the pilot flame 4h. Combustion products (e.g., carbon dioxide, steam, etc.) formed by the combustion of coal and hydrogen fuel can be transferred out of the combustion chamber toward the outlet of the boiler 1. Other coal particles that have not yet been ignited can circulate in the recirculation area 3a for subsequent combustion because these particles are exposed to the generated flame 4.

[0115] Since the recirculation flow path is affected by the secondary oxidant swirl output from the secondary oxidant outlet 21o, the use of the swirler 21s can help provide cascade ignition of the coal in the recirculation region. This cascade ignition effect can be further enhanced by using the swirlers 11s and / or 10s discussed above, that is, by having such swirlers promote the swirling of the hydrogen flow 10f and / or the hydrogen oxidant flow 11f output from the burner, so that the secondary oxidant flow swirls in the same direction as these other swirls in the combustion chamber 3.

[0116] The first distance d1 and the second distance d2 may be parts of a third distance d3, which may be a distance from the outlet 10o of the hydrogen conduit 10 to the distal end of the burner outlet 5a. The first distance d1 may be a distance less than the second distance d2. In some embodiments, the first distance d1 and the second distance d2 may be the same distance. In some embodiments, the ratio of the first distance to the second distance (e.g., d1 / d2) may be less than 1 and greater than 0.1, or less than 1 and greater than 0.5.

[0117] The first distance d1 and the second distance d2 may also be related to the radius of the annular gap associated with the inner hydrogen oxidant conduit 11 and the first pulverized coal conduit 19. For example, the radius r2 of the inner hydrogen oxidant conduit and the radius r3 of the first pulverized coal conduit may be related to the first distance and the second distance and used to specify a specific size or length for these distances. For example, the ratios d1 / r2 and d2 / r3 may be selected so that neither of these ratios is greater than 5 (e.g., d1 / r2 is less than or equal to 5 and greater than 0, and d2 / r3 is less than or equal to 5 and greater than 0).

[0118] As mentioned above, the first distance d1 and the second distance d2 can be selected to help facilitate the improvement of the pilot flame development. These distances can also help to transfer a smaller portion of coal to the pilot flame 4h, while a larger portion of coal is exported as unignited coal particles. In some embodiments, the chemical energy of the hydrogen stream used to form the pilot flame 4h can be at least ten times greater than the chemical energy of the transfer coal part mixed into the pilot flame 4h. As discussed below, this transfer of the coal part can also be provided by using a splitter 41 and / or a mixing conduit 31. Other embodiments can utilize the different transfers of coal particles to provide different chemical energy ratios for the hydrogen and transfer coal parts used to form the pilot flame 4h. Transferring coal to the pilot flame can enhance the pilot flame 4h to improve its firepower, thereby improving the pilot flame to effectively ignite the excess coal leaving the burner outlet 5a to form the ability of the larger flame emitted from the burner in the combustion chamber 3.

[0119] If available from Figure 6It is best understood that the first stream 19f of the mixture of pulverized coal and transport fluid may also include hydrogen mixed therein. For example, the first stream 19f of the mixture of pulverized coal and transport fluid may include hydrogen and air or oxygen-enriched air and pulverized coal particles. Hydrogen supply H2 can be supplied to mix with pulverized coal and oxidant fluid (e.g., gaseous air, gaseous oxygen-enriched air, air flow output from a compressor). For example, a hydrogen source (e.g., hydrogen from a container or hydrogen output from a processing unit of a plant including a boiler 1, etc.) can be supplied to the first stream 19f of the mixture of pulverized coal and transport fluid. This supply can occur before the first stream 19f is supplied to the inlet 19i of the first pulverized coal entrained fluid flow conduit 19. In some embodiments, the mixing of hydrogen H2 can be carried out via a mixing device located upstream of the inlet 19i or via hydrogen supplied to the supply conduit, and a mixture of solid coal particles entrained in air or other primary oxidant fluids passes through the supply conduit to include hydrogen in the supply of the first stream forming the mixture of pulverized coal and transport fluid, so that the mixture also includes hydrogen. A control valve CV may be located between a supply conduit of a coal supply stream entrained in the primary oxidant fluid and a source of hydrogen H2. The control valve may be adjustable between a closed position in which no hydrogen is added to the coal entrained oxidant supply stream and an open position in which hydrogen is added. The control valve may have a plurality of open positions so that different feed rates of hydrogen may be delivered to a first stream 19f of a mixture of pulverized coal and transport fluid that is fed toward an inlet 19i of a first pulverized coal entrained fluid flow conduit 19.

[0120] If available from Figure 6 As best seen, the hydrogen supplied to the inlet 10i of the hydrogen conduit 10 may be supplied from a separate hydrogen supply conduit. A control valve CV may be located between the source of hydrogen and the inlet 10i of the hydrogen conduit inlet 10i. The control valve may be adjustable between a closed position in which no hydrogen is supplied to the hydrogen conduit 10 and at least one open position in which hydrogen may be delivered to the inlet 10i of the hydrogen conduit 10. The control valve CV may have a plurality of open positions so that different supply rates of hydrogen may be delivered to the hydrogen conduit 10 of the burner 5. For example, the adjustment of the hydrogen flow may be made to take into account specific operating conditions of the boiler 1.

[0121] Embodiments of the burner 5 may include additional structure in the outlet 5a of the burner 5 to facilitate the formation of the pilot flame 4h and to generate a larger flame 4 within the combustion chamber 3 that may emanate from the pilot flame 4. Figures 7 to 16 An example of such a burner 5 is illustrated in the embodiment shown in FIG.

[0122] For example, the burner 5 may include a tapered outlet 11o of the inner hydrogen oxidant conduit 11. The distal end of the outlet may have a tapered portion 32 that is tapered so that it is narrower than the upstream middle portion of the conduit through which the hydrogen oxidant stream 11f passes. The tapering of the outlet 11o of the tapered portion 32 may begin at a tapered position 11t upstream of the outlet 11o. The tapering of the tapered portion 32 may end at or near the distal end of the outlet 11o to define the tapered portion 32.

[0123] The burner 5 may further include a mixing duct that is spaced apart from the distal end of the tapered portion 32 of the tapered outlet 11o of the inner hydrogen oxidant duct 11 by a gap 33 defined between the outlet 11o and the inlet of the mixing duct 31. The mixing duct 31 may be located between the outlet 19o of the first pulverized coal entrained fluid flow duct 19 and the tapered outlet 11o of the inner hydrogen oxidant duct 11. For example, the mixing duct 31 may be positioned along a flow path within the second distance d2 along which the hydrogen gas stream 10f and the hydrogen oxidant stream 11f may travel when the streams pass out of the outlet 11o of the hydrogen oxidant duct 11 and travel the second distance d2 to reach the outlet 19o of the first pulverized coal entrained fluid flow duct 19.

[0124] The gap 33 may be defined to facilitate mixing of a portion of the first flow 19f of the mixture of pulverized coal and transport fluid passing through the first pulverized coal entraining fluid flow conduit 19. The defined gap 33 may be in fluid communication with the first pulverized coal entraining fluid flow conduit 19 so that a portion of the first flow 19f is passed into the inlet 31i of the intermediate mixing conduit 31. The solid coal particles cp entrained in the primary oxidant (and hydrogen added thereto, if included) may be mixed with the hydrogen gas stream 10f and the hydrogen oxidant stream 11f supplied to the mixing conduit via the inlet 31i of the mixing conduit 31 to facilitate expansion or enhancement of the pilot flame 4h, which may include igniting the coal particles icp. The portion of the first flow 19f that is passed into the gap 33 to be supplied to the mixing conduit 31 may also be mixed with and / or pass along the hydrogen gas stream 10f and the hydrogen oxidant stream 11f directed into the mixing conduit 31 while the streams move along the gap distance dg.

[0125] The gap distance dg may be the distance between the outlet 11o of the inner hydrogen oxidant conduit 11 and the inlet 31i of the mixing conduit 31 (e.g., the axial distance between the inlet 31i and the outlet 11o that separates the outlet 11o from the mixing conduit inlet 31i). In such embodiments that may have this gap distance dg, the gap distance dg may be a portion of the second distance d2 and a portion of the third distance d3.

[0126] The formed pilot flame may heat other coal particles output from the first pulverized coal entraining fluid flow conduit 19 in the combustion chamber 3 to form a flame 4 around the pilot flame 4h. If hydrogen is included in the first stream 19f, the hydrogen may also be ignited in the combustion chamber due to the pilot flame 4h to form a flame 4 in the combustion chamber 3. Including hydrogen in the first stream 19f may be advantageous because hydrogen will typically ignite before coal due to its low ignition energy and high reactivity, so that the ignition hydrogen in the first stream may then contribute to the rapid ignition of the coal in the first stream 19f.

[0127] The flame 4 may emanate into the combustion chamber 3 and away from the burner outlet 5a. A recirculation zone 3a within the combustion chamber 3 may also be defined in the combustion chamber to facilitate circulation of the coal particles cp to further ignite the unignited coal to improve flame stability and combustion in the combustion chamber 3.

[0128] If available from Fig. 9 As best seen, the mixing conduit 31, the inner hydrogen oxidant conduit 11, and the hydrogen conduit 10 may be arranged to help provide a desired inflow of coal particles into the mixing conduit 31 to help generate a stronger, more stable flame 4 without extinguishing the flame, while also helping to avoid overheating of certain components (e.g., conduit walls that separate the hydrogen oxidant from the first flow 19f, etc.). For example, the outlet 10o of the hydrogen conduit 10 may be spaced an axial length LH2 from the tapered outlet 11o of the inner hydrogen oxidant conduit 11. The axial length LH2 may be a linear extension distance measured along a central axis 10ca between the outlet 10o of the hydrogen conduit 10 and the outlet 11o of the hydrogen oxidant conduit 11.

[0129] The hydrogen conduit 10 may also have a diameter DH2 (which may also be considered a width) through which the hydrogen passes as it passes through the hydrogen conduit 10. The inlet 31i of the mixing conduit 31 may be positioned a mixing conduit inlet distance Gc from a tapered location 11t of the inner hydrogen oxidant conduit 11 where the conduit begins to taper to its distal outlet 11o.

[0130] The mixing conduit inlet distance Gc may be the axial length between the inlet 31i of the mixing conduit 31 and the tapered position 11t of the inner hydrogen conduit 11 where the conduit begins to taper until its outlet 11o.

[0131] This exemplary arrangement and component configuration may be designed and configured to satisfy the following conditions:

[0132] (i)1≤L H2 / D H2 ≤5, and / or

[0133] (ii)0.05≤((2*G c *r1) / (r42 -r1 2 ))≤0.15;

[0134] Where r1 is the radius of the hydrogen conduit 10 , r2 is the radius of the inner hydrogen oxidant conduit 11 , r3 is the radius of the first pulverized coal entraining fluid flow conduit 19 , and r4 is the radius of the secondary oxidant conduit 21 .

[0135] Under conditions where LH2 / DH2 is less than 1, it has been found that the inflow of coal particles through the gap 33 may negatively affect the initial development of the pilot flame and may result in the extinguishing of the pilot flame. For situations where LH2 / DH2 is greater than 5, it has been found that the suction that can be generated for the inflow of coal particles from the first flow 19f may be too small and may severely restrict the inflow of coal particles. It is believed that gas expansion may be the main reason for this reduced suction effect that exists under this condition. In addition, the additional flame expansion that may be caused by LH2 / DH2 being greater than 5 can cause overheating of the conduit wall or other structure that can separate the hydrogen oxidant flow through the inner hydrogen oxidant conduit 11 from the first flow 19f of the mixture of pulverized coal and transport fluid through the first pulverized coal entrainment fluid flow conduit 19.

[0136] Some embodiments may be configured such that the diameter or width of the mixing conduit is smaller than the diameter or width of the inner hydrogen oxidant conduit 11. This may result in a portion of the outlet 11o of the inner hydrogen oxidant conduit protruding into the first pulverized coal entraining fluid flow conduit 19 and may affect how the first flow 19f is passed into the inlet 31i of the intermediate mixing conduit 31 and toward the outlet 19o of the first pulverized coal entraining fluid flow conduit 19. The effects that may be provided on the first flow 19f in this arrangement may be similar to those described below with respect to Figures 10 to 14 Discussion of the impact of implementation plans.

[0137] If available from Figures 10 to 14 It is understood that the outlet 11o of the inner hydrogen oxidant conduit 11 may include an expanded outlet portion 35 instead of a tapered portion. The distal end of the outlet 11o may have a widened expanded outlet portion 35 that is widened so that it is wider than the upstream middle portion of the conduit through which the hydrogen oxidant flow 11f passes (for example, the outlet area may be larger than the cross-sectional area of ​​the hydrogen oxidant conduit 11 upstream of the outlet 11o). For example, the outlet of the hydrogen oxidant conduit 11o may widen from a widened position until the distal end of the hydrogen oxidant outlet 11o, so that the outlet is wider at the distal end than at the widened position upstream of the distal end of the outlet 11o. As can be seen from Fig.11As best seen, this arrangement can result in the outermost portion of the enlarged outlet portion 35 of the outlet 11o extending beyond the inlet 31i of the mixing conduit 31. This can result in the enlarged outlet portion 35 protruding into the first pulverized coal entraining fluid flow conduit 19 and can affect how the first flow 19f is transferred into the inlet 31i of the intermediate mixing conduit 31 and toward the outlet 19o of the first pulverized coal entraining fluid flow conduit 19.

[0138] For example, the combination of the gap 33 in fluid communication with the first pulverized coal entraining fluid flow conduit 19 and the protruding portion of the outlet 11o extending into the first pulverized coal entraining fluid flow conduit 19 can help generate a split of the first flow 19f of the mixture of pulverized coal and the transport fluid. The split can result in a first portion of the first flow 19f including smaller-sized coal particles SP, which can pass through the gap 33 and enter the inlet 31i of the intermediate mixing conduit 31 to mix with the hydrogen gas flow 10f and the hydrogen oxidant flow 11f supplied to the mixing conduit 31. A second portion of the first flow 19f including larger-sized coal particles LP can pass through the first pulverized coal entraining fluid flow conduit 19 and along the outside of the intermediate mixing conduit 31.

[0139] Such positioning of the enlarged outlet 11o and the gap 33 can also help all of the output hydrogen gas stream 10f and the hydrogen oxidant stream 11f pass through the mixing conduit 31. For example, the first portion of the first stream 19f including the smaller particles SP driven through the gap 33 can help force all of the hydrogen gas and hydrogen oxidant of the hydrogen gas stream 10f and the hydrogen oxidant stream 11f to pass through the mixing conduit 31.

[0140] The gap 33 and the outlet 11o of the inner hydrogen oxidant conduit 11 can be positioned so that the flow of fine coal particles (e.g., smaller particles SP) and the associated portion of the first coal transport fluid carrying these particles through the gap 33 is driven by suction, which can be generated by the discharge velocity of hydrogen and hydrogen oxidant passing from the outlet 11o of the inner hydrogen oxidant conduit 11 toward the mixing conduit 31. This discharge velocity can facilitate the formation of a high-speed ignition flame 4h. To help provide this suction effect, the discharge velocity of the flow output from the outlet 11o of the inner hydrogen oxidant conduit can be greater than 45 meters per second (e.g., greater than or equal to 50 meters per second, greater than or equal to 100 meters per second, etc., while also being less than 400 meters per second or other upper limits that are not practical for a given design, etc.). In order to provide additional assistance to produce this suction effect on the first flow 19f of the mixture of pulverized coal and transport fluid near the gap 33, the outlet plane of the outlet 11o can be positioned so that it does not significantly retreat from the upstream end of the gap 33. For certain embodiments, the pumping effect can be adjusted by adjusting the velocity of hydrogen output from outlet 11o of the inner hydrogen oxidant conduit and the relative position between gap 33 and (i) outlet 10o of hydrogen conduit 10 and / or (ii) outlet 11o of the inner hydrogen oxidant conduit.

[0141] The suction that occurs can result in mixing of a portion of the first portion of the first flow 19f including the smaller particles SP, which is passed into the gap 33 to be fed into the mixing conduit 31, and also mixed with and / or passed along the hydrogen flow 10f and the hydrogen oxidant flow 11f directed into the mixing conduit 31 while these flows move along the gap distance dg. As described above, the gap distance dg can be the distance between the outlet 11o of the inner hydrogen oxidant conduit 11 and the inlet 31i of the mixing conduit 31 that separates these structures.

[0142] When the hydrogen gas flow and the hydrogen oxidant flow travel along the second distance d2 in the first pulverized coal entrained fluid flow conduit 19 and the mixing conduit 31 located therein, a pilot flame 4h can be formed. Smaller particle size coal can also be ignited to increase the chemical energy contained in the pilot flame. Smaller particle size may be advantageous for the pilot flame 4h because smaller particles ignite faster than larger particles of the same chemical composition. Larger size coal particles can be output from the outlet 19o of the first pulverized coal entrained fluid flow conduit 19 and transferred to the combustion chamber to ignite in the combustion chamber 3, thereby forming a flame that can be emitted from the burner outlet 5a around the pilot flame 4h. It can be imagined that transferring smaller size particles SP to the mixing conduit 31 can easily and quickly strengthen the pilot flame 4h due to the smaller volume and size of the particles. Then, the increased chemical and thermal energy of the enhanced pilot flame is used to more effectively burn the larger particles LP output to the combustion chamber 3.

[0143] If available from Figures 11 to 14 As best seen, embodiments utilizing an enlarged outlet portion 35 may be configured such that the outlet 10o of the hydrogen conduit 10 is located at different locations to provide different types of mixing of hydrogen, hydrogen oxidant, and a portion of the first stream 19f having coal particles entrained in the fluid, which may include oxidant and / or hydrogen, within the mixing conduit 31. The outlet 10o may be located at an axial distance XH2 relative to the outlet 11o of the inner hydrogen oxidant conduit 11. The axial distance XH2 may be a linear extension distance measured along a central axis 10ca between the outlet 10o of the hydrogen conduit 10 and the outlet 11o of the hydrogen oxidant conduit 11.

[0144] exist Fig.14 In the embodiment, the axial distance XH2 is less than 0 (for example, the outlet 11o is located downstream of the outlet 10o, so that the axial distance XH2 is -1 mm or less, -2 mm or less, -1 cm or less, etc.). Fig.12 In the embodiment of , the axial distance XH2 is 0, because the outlet 10o coincides with the outlet 11o (for example, the two outlets terminate at the same position, so that the axial distance XH2 is 0mm, 0cm, etc.). Fig.13 In an embodiment, the axial distance XH2 is greater than 0 (for example, the axial distance XH2 is greater than 0.1 mm or greater than 0.1 cm, greater than 1 mm, etc.).

[0145] Figures 10 to 14 These exemplary arrangements and component configurations may be designed and configured to satisfy the following conditions:

[0146] (i) -1≤X H2 / D H2 ≤5, and / or

[0147] (ii)0.05≤((2*dg*r1) / (r4 2 -r1 2 ))≤0.15;

[0148] Wherein dg is the gap distance dg, which may be the axial distance between the outlet 11o of the inner hydrogen oxidant conduit 11 and the inlet 31i of the mixing conduit 31, r1 is the radius of the hydrogen conduit 10, r2 is the radius of the inner hydrogen oxidant conduit 11, r3 is the radius of the first pulverized coal entraining fluid flow conduit 19, and r4 is the radius of the secondary oxidant conduit 21.

[0149] It should be understood that the linear measurement distance of the above-mentioned radius r1-r4 can be the distance extending vertically from the central axis 10ca to a specific inner side of the outer wall of the catheter.

[0150] Utilizing the above conditions can help optimize the implementation for a particular set of design criteria. It has been found that implementations utilizing an enlarged outlet portion 35 may require greater suction than implementations utilizing another type of outlet 11o configuration (e.g., a tapered outlet or a uniform diameter outlet) because the coal particle inflow may require a sharper bend in the particle flow path to pass into the gap 33 toward the inlet 31i of the mixing conduit 31. For the same suction, the mass flow of coal particles for implementations utilizing an enlarged outlet portion 35 may be lower than for implementations utilizing a tapered outlet 11o or a uniform diameter outlet 11o. In addition, the size distribution of particles supplied to the mixing conduit 31 through the gap 33 to allow the coal particles to flow in can be finer (e.g., a smaller size distribution), which can result in a higher ratio of particle surface area to mass. This can facilitate faster ignition of coal particles via the pilot flame, thereby helping to strengthen the pilot flame and improve its stability. This can also mean that the extinguishing of the pilot flame will not be as rapid as discussed above. Figures 7 to 9 On the contrary, for Figures 10 to 14 The design of the embodiment, arrangement and configuration to help meet the preselected particle extraction level may be a more important factor.

[0151] For some embodiments, it may be preferred to position the outlet 10o of the hydrogen conduit 10 downstream of the outlet 11o of the inner hydrogen oxidant conduit 11 (e.g., an axial distance XH2 greater than 0) because such positioning can help generate a desired level of suction due to the jet wake of the hydrogen output from the outlet 10o of the hydrogen conduit 10.

[0152] for Figures 10 to 14 In embodiments, it has been found that for XH2 / DH2 greater than 5, the jet wake suction may be reduced and the hydrogen conduit 10 may be more susceptible to coal particle impact and erosion. It has also been found that for XH2 / DH2 less than -1, the pressure that may be generated by the output of the hydrogen jet from the outlet 10o of the hydrogen conduit may cause the suction to be reduced and hinder the entrainment of coal particles (e.g., the coal particles are passed into the gap and the inlet 33i of the mixing conduit and are entrained in the fluid flow within the mixing conduit, etc.).

[0153] Figures 15 to 16Another burner outlet 5a arrangement is illustrated, which may utilize a flow splitter 41 that defines a radial gap to split a first flow 19f of a mixture of pulverized coal and a transport fluid (e.g., coal mixed with an oxidant stream such as air or oxygen-enriched air and optionally hydrogen as discussed above) into a first inner flow portion 19fi and a second outer flow portion 19fo. The flow splitter 41 may be a portion of a mixing conduit that is positioned to surround the outer peripheral portion of the outlet region of the hydrogen oxidant flow conduit 11, or may be a portion attached to or located near the mixing conduit 11. For example, the flow splitter 41 may be located around the outlet 11o of the hydrogen oxidant conduit 11 within the first pulverized coal entrained fluid flow conduit 19 to split the first flow 19f so that the inner flow portion 19fi of the first flow is supplied through a passage 41a defined between the inner side of the body of the flow splitter 41 and the outer side of the inner hydrogen oxidant conduit 11 and enters the mixing conduit 31. The mixing conduit 31 has an outlet 31o located downstream of the outlet 11o of the hydrogen oxidant conduit 11. The flows of hydrogen, hydrogen oxidant and inner flow portion 19fi (which may be considered the first portion of the first flow 19f) may pass through the mixing conduit 31 so that the flows mix therein and form the pilot flame 4h.

[0154] The outlet 31o of the mixing conduit 31 can provide a converging terminal to facilitate faster mixing of the inner flow portion 19fi with the pilot flame 4h. For example, the outlet 31o of the mixing conduit can be narrower than its inlet 31i or the middle portion between its inlet 31i and its outlet 31o to provide this converging terminal. In other configurations, the mixing conduit 31 can include a tapered configuration in which the cross-sectional area through which the fluid and coal particles flow is larger at its inlet 31i and smaller at its outlet 31o and / or middle portion to facilitate faster mixing of the coal particles from the inner flow portion 19fi with the pilot flame 4h and the hydrogen and hydrogen oxidant passing through the mixing conduit 31.

[0155] An outer flow portion 19fo of the first flow 19f (which may also be considered a second portion of the first flow 19f) may pass through the first pulverized coal entraining fluid flow conduit 19 along the outside of the mixing conduit 31 so that this flow portion remains separated from the hydrogen flow and hydrogen oxidant flow passing through the mixing conduit 31.

[0156] The flow divider 41, the mixing conduit 31, the inner hydrogen oxidant conduit 11, and the hydrogen conduit 10 can be arranged to help provide the desired inflow of coal particles to help generate a stronger, more stable flame 4 without extinguishing the flame, while also helping to avoid overheating of certain components (e.g., the conduit wall that separates the hydrogen oxidant from the first flow 19f, etc.). For example, the outlet 10o of the hydrogen conduit 10 can be separated from the outlet 11o of the inner hydrogen oxidant conduit 11 by an axial length LH2. The hydrogen conduit 10 can also have a diameter DH2 (which can also be considered a width) through which the hydrogen passes as it passes through the hydrogen conduit 10. The conduits can also be arranged and positioned so that their different radii (e.g., r1, r2, r3, and r4) help promote the desired level of radial mixing of the coal particles.

[0157] For example, Figures 15 to 16 The exemplary arrangements and component configurations of the embodiments may be designed and configured to satisfy the following conditions:

[0158] (i)1≤L H2 / D H2 ≤5, and

[0159] (ii)0.05≤((r6 2 -r5 2 ) / (r8 2 -r7 2 ))≤0.25;

[0160] The radius r5 is the outer radius of the hydrogen conduit 10 , the radius r6 is the inner radius of the splitter 41 , the radius r7 is the outer radius of the splitter 41 , and the radius r8 is the inner radius of the first pulverized coal entraining fluid flow conduit 19 .

[0161] In such a configuration, the radius r5 can be a linear measurement distance from the inner side of the outer wall of the hydrogen oxidant conduit 11 to the central axis 10ca (the radius r5 can also be considered as the radius of the hydrogen oxidant conduit 11 (similar to the radius r2 discussed above). The radius r6 can be a linear measurement distance between the central axis 10ca and the inner side of the diverter 41. The radius r7 can be a linear measurement distance between the outer side of the diverter 41 and the central axis 10ca. The radius r8 can be a linear measurement distance between the inner side of the outer wall of the first pulverized coal entrainment fluid flow conduit 19 and the central axis 10ca. Each of the above-mentioned linear measurement distances of the radii r5-r8 can be a linear distance extending vertically from the central axis 10ca.

[0162] The ratio (r62-r521) / (r82-r72)) may be considered as a ratio of cross-sectional areas Ar. The ratio Ar may be a ratio of cross-sectional areas between the inner coal flow passage and the outer coal flow passage separated by the flow divider 41.

[0163] Under conditions where LH2 / DH2 is less than 1, it has been found that the coal particle inflow through the passage 41a may be too high and may negatively impact the initial development of the pilot flame and may result in the extinguishing of the pilot flame. For situations where LH2 / DH2 is greater than 5, it has been found that the suction that can be generated for the coal particle inflow from the first flow 19f may be too small and may severely restrict the coal particle inflow. It is believed that gas expansion may be the primary cause of this reduced suction effect that exists under this condition. Furthermore, the additional flame expansion that may result from LH2 / DH2 being greater than 5 may result in overheating of the conduit wall or other structure that may separate the hydrogen oxidant flow through the inner hydrogen oxidant conduit 11 from the first flow 19f of the mixture of pulverized coal and transport fluid through the first pulverized coal entrainment fluid flow conduit 19.

[0164] Fig.17 and 18 Another embodiment of the burner is illustrated, which can utilize a first pulverized coal entraining fluid flow conduit 19 and a second pulverized coal entraining fluid flow conduit 29. Fig.17 As best seen, the supply of coal entrained in the primary transport gas may be supplied from at least one primary fuel source 45 toward the inlets 19i and 29i of the first pulverized coal entraining fluid flow conduit 19 and the second pulverized coal entraining fluid flow conduit 29. The primary fuel source 45 may be considered to be a source of pulverized coal or a source of pulverized coal entrained in a primary oxidant (e.g., air, oxygen-enriched air, etc.). An adjustable diverter valve AVS may be located between the primary fuel source 45 and the inlets 19i, 29i to regulate the flow of coal entrained in the primary oxidant supplied toward the inlets. The adjustable diverter valve AVS may be positioned such that the flow of the supply of coal entrained in the primary oxidant is diverted such that a first portion of the supply is supplied to the inlet 19i of the first pulverized coal entraining fluid flow conduit 19 and a second portion of the supply is supplied to the inlet 29i of the second pulverized coal entraining fluid flow conduit 29. In some configurations, these portions may be diverted such that a majority of the coal and primary oxidant are supplied to the outer second pulverized coal entraining fluid flow conduit 29. For example, 5%-40%, 10%-40%, 15%-30% or 10%-20% of the coal entrained in the primary oxidant can be supplied to the first pulverized coal entraining fluid flow conduit 19, and the remainder of the fuel (e.g., 60%-95%, 60%-90%, 85%-70%, 80%-90%, etc.) can be supplied to the second pulverized coal entraining fluid flow conduit 29.

[0165] In other embodiments, there may be a second coal source 45a (shown in phantom) that may be used to supply coal to the second pulverized coal entraining fluid flow conduit 29 via a second coal source supply conduit 45f that is connected to the supply conduit to supply a flow of pulverized coal to the inlet 29i of the second pulverized coal entraining fluid flow conduit 29. When the first coal source 45 is used to provide coal to the first pulverized coal entraining fluid flow conduit 19, such coal supply may be made from the second coal source 45a. In some embodiments, the first coal source 45 may be used to provide coal to both the first pulverized coal entraining fluid flow conduit 19 and the second pulverized coal entraining fluid flow conduit 29, and the second coal source 45a may be used to mix additional coal from another coal source into the supply to the second pulverized coal entraining fluid flow conduit 29.

[0166] The second coal source 45a can provide a coal source having coal that is different from the first coal source. For example, the second coal source 45a can have coal with a larger particle size distribution or a smaller particle size distribution, and / or also include different types of coal with different compositions and / or different combustion properties. The option of utilizing multiple sources of different types of coal can help provide operational flexibility and allow for adjustment of how coal is fed to the combustion chamber to allow for improved flame generation and stability within the combustion chamber.

[0167] Hydrogen may also be included in the fuel supply to the first pulverized coal entraining fluid flow conduit 19 and / or the second pulverized coal entraining fluid flow conduit 29. This arrangement may be Fig.17 Best understood. Similar to the above discussion Figure 6 The control valve CV arrangement shown in FIG. 1 can supply hydrogen to be mixed into the supply to be supplied to the inlet 19i of the first pulverized coal entraining fluid flow conduit 19. This same type of arrangement can be used to supply hydrogen to the second pulverized coal entraining fluid flow conduit 29, or to supply hydrogen to both supplies to be supplied to the first pulverized coal entraining fluid flow conduit 19 and the second pulverized coal entraining fluid flow conduit 29.

[0168] exist Figures 17 to 18 In some arrangements, hydrogen may not be supplied or injected into the second pulverized coal entraining fluid flow conduit 29, and hydrogen may be injected or included only in the first pulverized coal entraining fluid flow conduit 19. In such configurations, utilizing hydrogen only in the first coal entraining fluid flow conduit 19 (as well as utilizing hydrogen via the inner hydrogen conduit 10) may be more advantageously used to ignite the "inner" coal flow, which may then further enhance the pilot flame.

[0169] In other arrangements that may include hydrogen injected into the second stream 29f, the second stream 29f of the mixture of pulverized coal and transport fluid may include hydrogen and air or oxygen-enriched air and pulverized coal particles. Hydrogen supply H2 may be supplied to mix with pulverized coal and oxidant fluid (e.g., gaseous air, gaseous oxygen-enriched air, air stream output from a compressor). For example, a hydrogen source (e.g., hydrogen from a container or hydrogen output from a processing unit of a plant including a boiler 1, etc.) may be supplied to the second stream 29f of the mixture of pulverized coal and transport fluid. This supply may occur before the second stream 29f is supplied to the inlet 29i of the second pulverized coal entrained fluid flow conduit 29. In some embodiments, the mixing of hydrogen H2 may be carried out via a mixing device located upstream of the inlet 29i or via hydrogen supplied to the supply conduit, and a mixture of solid coal particles entrained in air or other primary oxidant fluids passes through the supply conduit to include hydrogen in the supply of the first stream forming a mixture of pulverized coal and transport fluid, so that the mixture also includes hydrogen. A control valve CV may be located between a supply conduit of a coal supply stream entrained in the primary oxidant fluid and a source of hydrogen H2. The control valve may be adjustable between a closed position in which no hydrogen is added to the coal entrained oxidant supply stream and an open position in which hydrogen is added. The control valve may have a plurality of open positions so that different supply rates of hydrogen may be delivered to a second stream 29f of a mixture of pulverized coal and transport fluid that is supplied toward an inlet 29i of a second pulverized coal entrained fluid flow conduit 29.

[0170] refer to Fig.17 The use of the second pulverized coal entraining fluid flow conduit 29 can allow different flow rates of coal entrained in the primary oxidant to be used at different locations relative to the formed pilot flame 4h. This can help provide further adjustability in outputting coal, oxidant and hydrogen to the combustion chamber via the burner 5 to generate a flame, thereby providing a stable flame, and improved operating performance, CO2 emissions and particle generation are reduced.

[0171] For example, the second pulverized coal entraining fluid flow conduit 29 may be utilized such that a greater or lesser flow rate of oxygen-entrained coal is output from outlet 29o into the combustion chamber as compared to the outlet of the first pulverized coal entraining fluid flow conduit 19. Such output of different coal flow rates from different outputs may allow for adjustment of flame generation to account for different fuel types, operating conditions in the boiler, formation of a desired recirculation zone 3a within the combustion chamber, and other operating parameters.

[0172] Embodiments of the burner 5 may permit replacement of pre-existing conventional installations utilizing diesel, propane, or natural gas. This may permit elimination of on-site storage of such fuels, as well as avoid the utilization of higher soot content flames that generate high particulate emissions that are not well captured in electrostatic precipitators or other filtration devices. This may improve emissions output from the boiler, as well as reduce fire hazards that may exist due to baghouses or other particulate retention devices used in such filtration devices.

[0173] In addition, embodiments of the burner 5 may permit the use of hydrogen as a pilot flame fuel. This may provide greater load regulation flexibility and faster ramp rates. For example, hydrogen fuel supplied via the internal hydrogen conduit 10 may provide enhanced ignitability to generate a pilot flame that may adapt to higher flow rates more quickly, thereby increasing the rate at which the flame temperature within the combustion chamber 3 may increase.

[0174] In addition, embodiments of the burner can provide significant advantages over plasma torches or other conventional devices that require the use of a cooling water circuit. Compared to these types of devices, embodiments of the burner 5 can be more durable (e.g., for a boiler, having a significantly longer useful life cycle), while also providing greater operational flexibility and reduced maintenance.

[0175] The utilization of hydrogen that can be provided by embodiments of the burner 5 can also allow the use of hydrogen storage infrastructure that may already exist in conventional plants. For example, hydrogen is often used for generator cooling. Pre-existing hydrogen storage infrastructure can be used to supply hydrogen to the hydrogen conduit to allow embodiments of the burner 5 to be more easily retrofitted into pre-existing boilers.

[0176] Hydrogen as a fuel source for pilot flame generation can also provide a more reactive fuel with a higher flame temperature than diesel, propane or natural gas. This can permit faster and more efficient combustion of coal or other fossil fuels.

[0177] Embodiments of the burner 5 may also permit relatively low hydrogen utilization to provide the generated flame. This may permit the boiler 1 to have improved cold start operation by using hydrogen to generate the pilot flame 4h, while also providing enhanced regulation during periods of lower demand on the boiler 1. For example, enhanced regulation features may be provided by regulating the flow rate of hydrogen output from the burner to account for lower demand. In addition, embodiments of the burner may be relatively inexpensive and include lower capital costs compared to conventional devices such as plasma torches.

[0178] Embodiments of the burner were used in confidential testing that was conducted to evaluate operational improvements that embodiments of the burner 5 may provide. In the first test, a burner having Figures 2 to 6A second test was conducted to evaluate the Figures 7 to 9 A third test was conducted to further evaluate the Figures 2 to 6 For these tests, the burner was installed in a pulverized coal test furnace for testing.

[0179] Table 1 below shows the use of Figures 2 to 6 The test results of a first test performed on an embodiment of the embodiment are shown.

[0180] Table 1: Test results of the test of the first exemplary embodiment of the burner

[0181]

[0182] Table 2 below shows the use of Figures 7 to 9 2 is a test result of a second test performed on an embodiment of the embodiment shown in FIG.

[0183] Table 2: Test results of the test of the second exemplary embodiment of the burner

[0184]

[0185]

[0186] As can be understood from the above, the test results of the two embodiments are very satisfactory. Relative to the results shown in Table 1, the results shown in Table 2 demonstrate higher efficiency (e.g., lower CO emissions, lower hydrogen flow rate). For example, CO emissions are an indicator that a portion of coal is not completely burned, and are generally closely related to the level of unburned carbon leaving the boiler. Therefore, the reduction in CO emissions that can be provided indicates that more coal is burned, and less unburned coal leaves the boiler (e.g., the boiler operates more efficiently and burns more coal).

[0187] It is believed that the second test of the second exemplary embodiment of the burner nozzle obtained improved test results because the controlled diversion of the coal and primary oxidant flow is present just upstream of the outlet 5a of the burner nozzle, which can be provided via the gap 33 and / or the mixing conduit 31. The portion of coal diverted to the hydrogen flow 10f and the hydrogen oxidant flow 11f output from the hydrogen oxidant conduit outlet 11o is a complex function of the hydrogen velocity leaving the central conduit, the diameter of the hydrogen oxidant conduit, the gap size, the coal particle size distribution, and the velocity of the coal / primary oxidant flow. For the test results given in Table 2, the calculated range of diverted coal is between about 0.3% and 8% of the total coal flow rate entering the burner nozzle, while the hydrogen nozzle velocity varies between about 40 m / s and 300 m / s, respectively. Because the burner size and coal supply are fixed for these same tests, it is found that the controlling factor that dominates the diverted coal portion during these tests is the hydrogen nozzle velocity. The tests conducted show that in order to optimize performance according to the first set of design criteria, the maximum hydrogen nozzle velocity can be determined according to the maximum percentage required to divert the coal flow. Test results indicate that additional diverted coal mixed with hydrogen via the mixing conduit 31 can help enhance the pilot flame 4h generated via the hydrogen flow and hydrogen oxidant flow, increase the flame power, and thereby improve its ability to effectively ignite and burn the remaining coal exiting the burner outlet 5a.

[0188] It has been found that a suitable maximum value of the diverted coal flow that may be required during the initial startup of a coal-fired boiler to meet a certain set of preselected design criteria may be no greater than about 25% of the total burner coal flow rate, and a preferred maximum range may be between about 5% and 15% of the total burner coal flow rate. The remainder or undiverted portion of the coal flow (e.g., 75% or more of the total burner coal flow rate, or 85%-95% of the total burner coal flow rate) passes along the outside of the mixing conduit 31 so that it is not mixed with hydrogen before being output from the burner outlet 5a.

[0189] Fig. 20 and 21 This demonstrates the use of a Figures 2 to 6 2. Test results of an additional third test performed on an embodiment of the embodiment shown in FIG. Figures 20 to 21 The test results are from using Figures 2 to 6 These tests were conducted to determine the effectiveness of using high concentrations of oxygen in the hydrogen oxidant (eg, hydrogen oxidant conduit 11) to enhance flame stability, particularly after startup during part load operation of a coal-fired boiler.

[0190] The results of the third test conducted are summarized in Fig.21For this third test conducted, no hydrogen was used. No hydrogen was utilized in this test because the tests conducted were conducted after startup so that the combustion chamber wall temperatures were similar to the temperatures of the boiler at reduced operating loads. The oxygen concentration in the hydrogen oxidant stream output from the hydrogen oxidant conduit 11 was systematically reduced from 40 vol% to 20.9 vol% by increasing the flow rate of nitrogen (N2) in the hydrogen oxidant stream while keeping the flow rate of oxygen (O2) fixed at approximately 7.5% of the total oxidant oxygen (O2) used for combustion (the remainder being oxygen in the primary and secondary air through the secondary air conduit 21 and the first coal entrainment fluid flow conduit 19). As the oxygen (O2) concentration decreased during the test, the stability of the coal flame weakened until flame blowout occurred at an oxygen concentration of 20.9 vol%.

[0191] The reason for the improved flame stability at higher oxygen concentrations observed in the tests conducted is believed to be the significant reduction in the coal ignition energy. Ignition energy data were independently obtained for bituminous coal with 35% volatile matter and are summarized in Fig. 20 During testing, it was found that the required ignition energy decreased by about 100 times when the oxidant oxygen (O2) concentration was increased from 20.9 vol% to 45 vol%. The decrease was most dramatic when the oxygen concentration was just above that in air, and gradually approached a limiting low value as the oxygen concentration increased. Tests that have been conducted have shown that an oxygen concentration in the hydrogen oxidant flow through the inner hydrogen oxidant conduit 11 of greater than about 35 vol% may be sufficient to maintain partial load coal burner flame stability under blow-out conditions with air as the hydrogen oxidant. The results also show that the increased oxygen concentration can also reduce hydrogen consumption during startup operations.

[0192] These test results further illustrate that embodiments of the burner can provide significantly improved operation while also providing improved emissions with fewer particulates while permitting implementations to incur lower operating and capital costs.

[0193] The embodiments of the burner 5 discussed herein may also be used in methods of operating a boiler 1 and other types of combustion devices that may include a combustion chamber 3. For example, embodiments of the method may be used in conjunction with a combustion chamber that utilizes particulate coal material as a primary fuel to form at least one flame 4 in the combustion chamber 3. Fig.19An example of this method is illustrated. For example, in a first step S1, a boiler 1 or other device having a combustion chamber 3 can be started by supplying a flow of hydrogen, a hydrogen oxidant, pulverized coal entrained in the oxidant, and a secondary oxidant to at least one burner to generate at least one flame 4 in the combustion chamber 3. In a second step S2 of the method, a first portion of the pulverized coal supplied to the burner can be mixed with a hydrogen flow and a hydrogen oxidant flow passing through the burner, while these flows are located within the burner, near the outlet 5a of the burner 5, to generate a pilot flame 4h, while a second portion of the pulverized coal passes through the burner and is output to the combustion chamber via the burner outlet 5a. The generated pilot flame 4h can be emitted from the outlet 5a of the burner and enter the combustion chamber to facilitate the combustion of the second portion of the coal in the combustion chamber, thereby generating a flame in the combustion chamber 3. After the combustion chamber has reached a preselected threshold operating temperature or is within a preselected operating temperature range, in a third step S3, the flow rate of hydrogen, pulverized coal and / or oxidant flow supplied to one or more of the burners 5 can be adjusted to take into account demand, flame stability, flame temperature and / or other operating parameters.

[0194] The third step S3 may include several different actions. For example, the third step S3 may include stopping the injection of hydrogen into the combustion chamber after the combustion chamber is at the desired temperature and / or after the flame formed in the combustion chamber has sufficient flame stability. Then, the injection of hydrogen may also be restarted during boiler operation to facilitate a lower boiler load with enhanced flame stability, which may be desired, for example, before boiler regulation. In addition (or alternatively), before rising from one boiler load to another higher boiler load, the injection of hydrogen may be restarted, or the rate of hydrogen supplied to the burner 5 to be output from the burner 5 may be increased. This increase or restart of the hydrogen injection may help to speed up the ramp rate of the temperature in the combustion chamber.

[0195] As yet another example, during part load operation, the third step S3 may include supplying a hydrogen oxidant stream to the burner without further injecting hydrogen. The hydrogen oxidant stream may include a high concentration of oxygen to help improve part load operation without further use of hydrogen injection. As discussed above, utilizing this enhanced oxygen concentration in the hydrogen oxidant stream may be used to enhance flame stability during part load operation without injecting hydrogen into or outputting hydrogen from the burner (e.g., via the internal hydrogen conduit 10).

[0196] The embodiment of the method can also utilize other elements or steps. For example, it is possible to facilitate the mixing of pulverized coal with these flows by making the hydrogen gas flow and the hydrogen oxidant flow pass along the second distance d2 when they move toward the outlet 5a or by using a mixing conduit 31 and / or a flow divider 41. As another example, the pulverized coal flow can be split into a first part and a second part, while also selecting the particle size by transferring the smaller size particles in the coal particle flow to the hydrogen gas flow and the hydrogen oxidant flow. For example, this can be provided by utilizing the enlarged outlet of the gap 33 and the hydrogen oxidant conduit as discussed above. As another example, as discussed above, before the flow is supplied to the burner to be used in combination with the primary hydrogen flow through the inner hydrogen conduit 10, hydrogen can be mixed with the pulverized coal entrained in the primary oxidant. The pulverized coal in this flow can then be transferred so that when the primary hydrogen flow output from the hydrogen conduit 10 and the hydrogen oxidant flow output from the hydrogen oxidant conduit 11 pass along the second distance d2 toward the outlet 5a of the burner 5, the first part is mixed with these flows.

[0197] Embodiments of the method may also include other steps. For example, before the first step S1, an embodiment of the burner may be retrofitted into a pulverized coal boiler. For example, an old conventional burner may be replaced with an embodiment of the burner 5. In addition, a conduit may be adjusted or provided to supply at least one hydrogen stream, oxidant stream and / or at least one pulverized coal entrained in an oxidant stream or other type of transport fluid to the installed burner. Embodiments of this type of method may also be considered as methods for installing a burner into a boiler to improve the operation of the boiler or for retrofitting a boiler to include at least one new burner.

[0198] As another example, the method may also include building a new boiler for the plant and including an embodiment of the burner in the new boiler. Embodiments of this type of method may also be considered as a method for installing a new boiler.

[0199] Embodiments of the method, boiler 1, and burner 5 may be configured to include process control elements positioned and configured to monitor and control operations (e.g., temperature and pressure sensors, flow sensors, an automated process control system having at least one workstation including a processor, non-transitory memory, and at least one transceiver for communicating with the sensor elements, valves, and a controller for providing a user interface for the automated process control system that may be run at the workstation and / or another computer device of the system, etc.). The automated process control system may be used to help monitor and control the operation of the boiler 1 and / or burner 5. This process control system may also facilitate specific implementations of embodiments using the boiler 1 and / or burner 5.

[0200] As another example, the coal transport fluid in which the coal particles are entrained can be a suitable gas or gas mixture that can entrain coal particles to supply coal to the combustion chamber. The transport fluid may include an oxidant component or may not include any oxidant component. Examples of transport fluids for entraining coal particles in the first stream 19f of the mixture of pulverized coal and transport fluid may include air, nitrogen, air mixed with nitrogen, carbon dioxide, oxygen-enriched air, air mixed with hydrogen, oxygen-enriched air mixed with hydrogen, flue gas including combustion products, or other suitable gas streams that may include gas mixtures or single gases. Examples of transport fluids for entraining coal particles in the second stream of the mixture of pulverized coal and transport fluid may include air, nitrogen, air mixed with nitrogen, carbon dioxide, oxygen-enriched air, air mixed with hydrogen, oxygen-enriched air mixed with hydrogen, flue gas including combustion products, or other suitable gas streams that may include gas mixtures or single gases.

[0201] It should be understood that the embodiments explicitly shown and discussed herein can be modified to meet a set of specific design goals or a set of specific design criteria. For example, embodiments of the burner 5 can utilize other suitable preselected flow rates of the flow of oxidant, hydrogen, and pulverized coal or flow rates within a preselected supply flow rate range to meet a set of specific design criteria. As another example, the distances of the first distance d1, the second distance d2, and the third distance d3 and / or the values ​​of one or more radii (e.g., radius r1, radius r2, radius r3, radius r4, etc.) or other dimensional design parameters discussed herein can be different values ​​to meet a set of specific design criteria taking into account the combustion chamber size design, the desired flow rate, the coal supply type, and other design considerations.

[0202] As another example, it is contemplated that a specific feature described separately or as part of an embodiment may be combined with other separately described features or parts of other embodiments. Therefore, the elements and actions of the various embodiments described herein may be combined to provide additional embodiments. Therefore, although certain exemplary embodiments of boilers, burners, methods for operating burners, methods for operating boilers and / or burners, and methods for making and using the same have been shown and described above, it should be clearly understood that the present invention is not limited thereto, but may be otherwise differently implemented and practiced within the scope of the appended claims.

Claims

1. A burner for a combustion chamber, the burner comprising: a first pulverized coal entraining fluid flow conduit; Internal hydrogen conduit; and a hydrogen oxidant conduit positioned between the first pulverized coal entraining fluid flow conduit and the inner hydrogen conduit; The outlet of the inner hydrogen conduit is positioned at a first distance from the outlet of the hydrogen oxidant conduit so that hydrogen output from the outlet of the inner hydrogen conduit passes through a portion of the hydrogen oxidant conduit to reach the outlet of the hydrogen oxidant conduit; and The outlet of the hydrogen oxidant conduit is a second distance away from the outlet of the first pulverized coal entrained fluid flow conduit, so that the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit pass through a portion of the first pulverized coal entrained fluid flow conduit to be output from the burner.

2. The burner of claim 1, wherein the first pulverized coal entrainment fluid flow conduit comprises an annular conduit and the hydrogen oxidant conduit comprises an annular conduit.

3. The burner according to claim 2, comprising: A secondary oxidant conduit is positioned near the periphery of the first pulverized coal entraining fluid flow conduit so that the secondary oxidant flow passes through the burner and enters the combustion chamber, and at least one swirler is positioned in the secondary oxidant conduit so that the secondary oxidant flow swirls in the combustion chamber.

4. The burner according to claim 2, comprising: a second pulverized coal entraining fluid flow conduit, the second pulverized coal entraining fluid flow conduit being positioned proximate a periphery of the first pulverized coal entraining fluid flow conduit such that the first pulverized coal entraining fluid flow conduit is interposed between the second pulverized coal entraining fluid flow conduit and the hydrogen oxidant conduit; and A secondary oxidant conduit is positioned near the periphery of the second pulverized coal entraining fluid flow conduit to allow secondary oxidant flow through the burner and into the combustion chamber.

5. The burner according to claim 1, comprising: A mixing conduit is positioned in the portion of the first pulverized coal entraining fluid flow conduit, and the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit pass through the mixing conduit to be output from the burner.

6. A burner according to claim 5, wherein the outlet of the hydrogen oxidant conduit is a tapered outlet having a tapered portion, and a gap is defined between the outlet of the hydrogen oxidant conduit and the mixing conduit, so that a first portion of the pulverized coal passing through the first pulverized coal entraining fluid flow conduit passes through the gap to be mixed with the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit in the mixing conduit, while a second portion of the pulverized coal passing through the first pulverized coal entraining fluid flow conduit passes along the outside of the mixing conduit.

7. A burner according to claim 5, wherein the outlet of the hydrogen oxidant conduit is an enlarged outlet having an enlarged portion, and a gap is defined between the outlet of the hydrogen oxidant conduit and the mixing conduit, so that a first portion of the pulverized coal passing through the first pulverized coal entraining fluid flow conduit passes through the gap to be mixed with the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit in the mixing conduit, while a second portion of the pulverized coal passing through the first pulverized coal entraining fluid flow conduit passes along the outside of the mixing conduit.

8. The burner of claim 1, wherein the first pulverized coal entrained fluid flow conduit is positioned to receive a flow of pulverized coal entrained within a fluid comprising hydrogen.

9. The burner according to claim 5, comprising: A flow divider is positioned between the first pulverized coal entraining fluid flow conduit and the hydrogen oxidant conduit, adjacent to the outlet of the hydrogen oxidant conduit, to transfer a portion of the pulverized coal along a channel defined between the flow divider and the hydrogen oxidant conduit, thereby mixing the portion of the pulverized coal with the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit in the mixing conduit.

10. The burner according to claim 1, comprising: a secondary oxidant conduit positioned adjacent a periphery of the first pulverized coal entraining fluid flow conduit to allow secondary oxidant flow through the burner and into the combustion chamber; and a mixing conduit positioned in the portion of the first pulverized coal entraining fluid flow conduit through which the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit pass before being output from the burner; The outlet of the inner hydrogen conduit is spaced apart from the outlet of the hydrogen oxidant conduit by an axial length L H2 The inner hydrogen conduit also has a diameter D H2 ; The inlet of the mixing conduit is spaced from the outlet of the hydrogen oxidant conduit by a distance G. c , the hydrogen oxidant conduit begins to taper at the tapered position until the outlet of the hydrogen oxidant conduit; and in: (i)1≤L H2 / D H2 ≤5, and / or (ii)0.05≤((2*G c *r1) / (r4 2 -r1 2 ))≤0.15; Wherein r1 is the radius of the inner hydrogen conduit, r2 is the radius of the hydrogen oxidant conduit, r3 is the radius of the first pulverized coal entraining fluid flow conduit, and r4 is the radius of the secondary oxidant conduit.

11. The burner according to claim 10, wherein the inlet distance G c is the axial length of the gap between the inlet of the mixing conduit and the tapered location of the hydrogen oxidant conduit.

12. The burner according to claim 1, comprising: a secondary oxidant conduit positioned adjacent a periphery of the first pulverized coal entraining fluid flow conduit to allow secondary oxidant flow through the burner and into the combustion chamber; and a mixing conduit positioned in the portion of the first pulverized coal entraining fluid flow conduit, the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit passing through the mixing conduit before being output from the burner, the inlet of the mixing conduit being spaced apart from the outlet of the hydrogen oxidant conduit by a gap having a gap distance; The outlet of the inner hydrogen conduit has an axial distance X relative to the outlet of the hydrogen oxidant conduit. H2 The inner hydrogen conduit also has a diameter D H2 ; The inlet of the mixing conduit is spaced the gap distance from the outlet of the hydrogen oxidant conduit; and in: (i) -1≤X H2 / D H2 ≤5, and / or (ii)0.05≤((2*dg*r1) / (r4 2 -r1 2 ))≤0.15; Wherein dg is the gap distance, r1 is the radius of the inner hydrogen conduit, r2 is the radius of the hydrogen oxidant conduit, r3 is the radius of the first pulverized coal entraining fluid flow conduit, and r4 is the radius of the secondary oxidant conduit.

13. The burner of claim 12, wherein the gap distance is an axial distance between the outlet of the hydrogen oxidant conduit and the inlet of the mixing conduit.

14. The burner according to claim 1, comprising: a mixing conduit positioned in the portion of the first pulverized coal entraining fluid flow conduit, the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit passing through the mixing conduit to be output from the burner, the inlet of the mixing conduit being spaced apart from the outlet of the hydrogen oxidant conduit by a gap having a gap distance; a flow splitter positioned to surround an outer peripheral portion of an outlet region of the hydrogen oxidant flow conduit in the first pulverized coal entrained fluid flow conduit to split the first pulverized coal entrained fluid flow into a first inner flow portion and a second outer flow portion, the first inner flow portion being guided to the inlet of the mixing conduit to pass through the mixing conduit, and the second outer flow portion passing along an outer side of the mixing conduit; The outlet of the inner hydrogen conduit is spaced apart from the outlet of the hydrogen oxidant conduit by an axial length L H2 The inner hydrogen conduit also has a diameter D H2 ; The inlet of the mixing conduit is spaced the gap distance from the outlet of the hydrogen oxidant conduit; and in: (i)1≤L H2 / D H2 ≤5, and <h2 style=";text-align:left;direction:ltr">(ii) 0.05≤((r6<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> -r5<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> ) / (r8<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> -r7<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> ))≤0.25; Wherein r5 is the outer radius of the hydrogen conduit, r6 is the inner radius of the splitter, r7 is the outer radius of the splitter, and r8 is the inner radius of the first pulverized coal entraining fluid flow conduit.

15. A burner according to claim 14, wherein the splitter is positioned between the first pulverized coal entraining fluid flow conduit and the hydrogen oxidant conduit, adjacent to the outlet of the hydrogen oxidant conduit, to transfer the first inner flow portion along a channel defined between the splitter and the hydrogen oxidant conduit, thereby mixing the pulverized coal of the first inner portion with the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit in the mixing conduit.

16. A boiler, comprising: At least one burner positioned to generate at least one flame within the combustion chamber, the at least one burner comprising a first burner, the first burner being the burner of claim 1.

17. The boiler according to claim 16, further comprising: a pulverized coal source connected to an inlet of the first pulverized coal entraining fluid flow conduit; a hydrogen source connected to the inlet of the inner hydrogen conduit; and An oxidant flow source is connected to the inlet of the hydrogen oxidant conduit.

18. The boiler according to claim 16, comprising: A hydrogen source is positioned to inject hydrogen into a flow of pulverized coal entrained within a fluid, and wherein the first pulverized coal entrained fluid flow conduit is positioned to receive the flow of pulverized coal entrained within the fluid, the fluid comprising an oxidant and the hydrogen from the hydrogen source.

19. A method for generating a flame in a combustion chamber of a combustion device, the method comprising: supplying hydrogen, a hydrogen oxidant flow, and first pulverized coal entrained in the oxidant flow to a burner, such that the hydrogen passes through an inner hydrogen conduit of the burner, the hydrogen oxidant flow passes through a hydrogen oxidant conduit of the burner positioned between a first pulverized coal entraining fluid flow conduit and the inner hydrogen conduit, and the first pulverized coal entrained in the oxidant flow passes through the first pulverized coal entraining fluid flow conduit; outputting the hydrogen from an outlet of the inner hydrogen conduit such that when the hydrogen passes from the outlet of the inner hydrogen conduit to the outlet of the hydrogen oxidant conduit, the hydrogen passes through a first distance such that the hydrogen output from the outlet of the inner hydrogen conduit passes through a portion of the hydrogen oxidant conduit to reach the outlet of the hydrogen oxidant conduit; and The hydrogen and the hydrogen oxidant flow are output from the outlet of the hydrogen oxidant conduit so that when the hydrogen is transferred from the outlet of the hydrogen oxidant conduit to the outlet of the first pulverized coal entrained fluid flow conduit, the hydrogen and the hydrogen oxidant flow pass through a second distance so that the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit pass through a portion of the first pulverized coal entrained fluid flow conduit, thereby forming an ignition flame emitted from the outlet of the burner.

20. The method according to claim 19, comprising: A first portion of the first pulverized coal entrained in the oxidant flow is separated from a second portion of the first pulverized coal entrained in the oxidant flow, so that the first portion of the first pulverized coal entrained in the oxidant flow is mixed with the hydrogen and the hydrogen oxidant flow when the hydrogen and the hydrogen oxidant flow pass along the second distance in the burner to form the ignition flame, and at the same time, the second portion of the first pulverized coal entrained in the oxidant flow passes through the first pulverized coal entraining fluid flow conduit to be output into the combustion chamber.

21. The method according to claim 19, comprising: Before the first pulverized coal entrained in the oxidant flow is supplied to the burner, hydrogen is injected into the first pulverized coal entrained in the oxidant flow, so that the first pulverized coal entrained in the oxidant flow passing through the first pulverized coal entrainment fluid flow conduit includes hydrogen, pulverized coal and oxidant.

22. A burner for a combustion chamber, the burner comprising: a first pulverized coal entraining fluid flow conduit; Internal hydrogen conduit; and a hydrogen oxidant conduit positioned between the first pulverized coal entraining fluid flow conduit and the inner hydrogen conduit; a mixing conduit positioned in the first pulverized coal entrained fluid flow conduit so that hydrogen output from the outlet of the inner hydrogen conduit and hydrogen oxidant output from the outlet of the hydrogen oxidant conduit can pass through the mixing conduit to mix with a first portion of the pulverized coal flow entrained in the fluid capable of passing through the first pulverized coal entrained fluid flow conduit to be output from the burner as a mixture surrounding a flame formed by combustion of the hydrogen, the hydrogen oxidant and a portion of the pulverized coal within the first portion of the pulverized coal flow entrained in the fluid; The mixing conduit is positioned in the first pulverized coal entraining fluid flow conduit so that the second portion of the pulverized coal flow entrained in the fluid passing through the first pulverized coal entraining fluid flow conduit can be separated from the first portion of the pulverized coal flow entrained in the fluid via the mixing conduit, so that the second portion is discharged from the burner together with the flame and the unburned portion of the mixture of hydrogen, hydrogen oxidant and the first portion of the pulverized coal flow entrained in the fluid.

23. The burner according to claim 22, comprising: a secondary oxidant conduit positioned about a periphery of the first pulverized coal entraining fluid flow conduit to allow secondary oxidant flow through the burner and into the combustion chamber; and wherein the outlet of the inner hydrogen conduit is located at an axial distance X relative to the outlet of the hydrogen oxidant conduit H2 and the inner hydrogen conduit has a diameter D H2 , and there is a gap having a gap distance between the inlet of the mixing conduit and the outlet of the hydrogen oxidant conduit, the gap separating the inlet of the mixing conduit from the outlet of the hydrogen oxidant conduit, wherein: (i) -1≤X H2 / D H2 ≤5, and / or (ii)0.05≤((2*dg*r1) / (r4 2 -r1 2 ))≤0.15; Wherein dg is the gap distance, r1 is the radius of the inner hydrogen conduit, r2 is the radius of the hydrogen oxidant conduit, r3 is the radius of the first pulverized coal entraining fluid flow conduit, and r4 is the radius of the secondary oxidant conduit.

24. The burner according to claim 23, wherein the axial distance X H2 is the axial distance between the outlet of the hydrogen oxidant conduit and the inlet of the mixing conduit.

25. The burner according to claim 24, wherein the axial distance X H2 is less than 0, so that the outlet of the inner hydrogen conduit is positioned at a first distance from the outlet of the hydrogen oxidant conduit, so that the hydrogen output from the outlet of the inner hydrogen conduit passes through a portion of the hydrogen oxidant conduit to reach the outlet of the hydrogen oxidant conduit.

26. The burner according to claim 24, wherein the axial distance X H2 is 0, so that the outlet of the inner hydrogen conduit coincides with the outlet of the hydrogen oxidant conduit.

27. The burner according to claim 24, wherein the axial distance X H2 is greater than 0, so that the outlet of the inner hydrogen conduit is located inside the mixing conduit.

Images