Inlet head
The inlet head assembly with integrated burner and nozzles for direct ignition addresses deposit and corrosion issues in abatement apparatuses, achieving efficient combustion and reduced fuel consumption by integrating a standing flame and sheath flow compositions.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- EDWARDS LTD
- Filing Date
- 2025-11-04
- Publication Date
- 2026-05-15
AI Technical Summary
Existing abatement apparatuses face issues with deposit formation and corrosion due to harsh environments caused by effluent gas streams containing particulates and aerosols, leading to flow path blockages and increased fuel consumption, while maintaining abatement efficacy is desired.
An inlet head assembly with integrated burner element and nozzles for direct ignition of effluent gas streams, utilizing a standing flame to initiate combustion efficiently, reducing fuel requirements and minimizing deposit formation through sheath flow compositions like nitrogen and air.
The solution provides efficient combustion of effluent gases with reduced fuel consumption, minimizes deposit formation, and facilitates easier maintenance by integrating components within the inlet head assembly, enhancing abatement apparatus efficiency.
Smart Images
Figure GB2025052406_15052026_PF_FP_ABST
Abstract
Description
[0001] Inlet Head
[0002] Field
[0003] The present invention relates to an inlet head assembly for capping a combustion chamber of an abatement apparatus. The present invention also relates to an abatement apparatus, and to a method for abating an effluent gas stream.
[0004] Background
[0005] Abatement systems are known and are typically used for the treatment of effluent gas streams from a manufacturing process tool. The process tool may be used in, for example, semiconductor or flat panel display fabrication processes. Typically, before the effluent gas stream is vented to the atmosphere, it must be treated to remove selected components therefrom.
[0006] Some known abatement apparatus use combustion to remove compounds from the effluent gas stream. The abatement system may comprise a combustion chamber. An inlet head assembly may be arranged at the inlet of the combustion chamber. A fuel gas is mixed with the effluent gas stream and that gas stream mixture is conveyed through the inlet head assembly into an abatement chamber for abatement therein. The treated gas stream exiting the abatement apparatus may then be vented to the atmosphere or may undergo further abatement steps.
[0007] The abatement of an effluent gas stream is a harsh environment for components. The effluent gas stream may contain particulates and aerosols. This may result in the formation of deposits within the combustion chamber. Particularly, deposits may form within the inlet head assembly. The deposits may block or restrict flow paths within the system.
[0008] Additionally, the abatement apparatus may comprise components (e.g. spray nozzles) that introduce liquids and vapours into the abatement apparatus. This may accelerate corrosion of components of the abatement apparatus.
[0009] Additionally, there is a desire to provide a more efficient abatement apparatus. Particularly, there is a desire to reduce the fuel consumption of the abatement apparatus, whilst maintaining or improving abatement efficacy. The present invention aims to solve, at least in part, these and other problems associated with the prior art.
[0010] Summary
[0011] In an aspect, the present invention provides an inlet head assembly for capping a combustion chamber of an abatement apparatus. The inlet head assembly comprises a head plate. The inlet head assembly further comprises a plurality of inlet nozzles extending through the head plate. Each inlet nozzle is configured to convey an effluent gas stream into the combustion chamber. The inlet head assembly further comprises an ignition nozzle extending through the head plate.
[0012] The inlet head assembly further comprises a burner element arranged within the head plate between the inlet nozzles. The burner element is configured to convey a fuel gas composition into the combustion chamber. The ignition nozzle is configured to ignite the fuel gas composition exiting the burner element to provide a standing flame. Said standing flame is configured to initiate combustion of the effluent gas stream exiting the inlet nozzles.
[0013] The present invention may be configured to initiate combustion of the effluent gas stream exiting the inlet nozzles to abate one or more components of the effluent gas stream. Preferably, the effluent gas stream may be the exhaust from a semiconductor manufacturing process tool.
[0014] When arranged at an inlet of a combustion chamber of the abatement apparatus, the inlet head assembly may provide a portion of the internal surface of the combustion chamber. An inner face of the head plate may provide said portion. The inner face may face towards the combustion chamber when in use. The inner face may provide an internal surface of the combustion chamber. Preferably, the inner face may be a surface of the generally planar portion of the head plate.
[0015] The head plate may be substantially cylindrical. A central axis of the head plate may be substantially coaxial with a central axis of the combustion chamber. The head plate may be coupled to inlet of a housing defining a portion of the combustion chamber. The head plate may comprise a flange configured to be coupled to the housing.
[0016] The burner element may be integral with the head plate. Preferably, the burner element may be arranged within the head plate. The burner element may extend through the head plate. A surface of the burner element may define a portion of the internal surface of the combustion chamber. Preferably, said surface may be flush with, or substantially parallel to, the inner face of the head plate.
[0017] The inlet nozzles may be configured to be fluidly connected to a process tool. In use, one or more of the inlet nozzles may convey an effluent gas stream from one or more process tools. By way of example, the process tool(s) may be used in the fabrication of semiconductor components and / or flat panel displays. Each inlet nozzle may be configured to deliver an effluent gas stream into the combustion chamber.
[0018] The inlet nozzle(s) may comprise further inject ports configured to introduce gases to the effluent gas stream. Each inlet nozzle may comprise an effluent stream conduit configured to convey the effluent gas stream into the inlet nozzle. Each inlet nozzle may further comprise an inlet conduit fluidly coupled with the effluent stream conduit and configured to convey the effluent stream received from the effluent stream conduit to an abatement chamber of the abatement apparatus. The inlet conduit of the inlet nozzle may be coaxial with the central axis of the conduit of the head plate.
[0019] Each of the inlet nozzles may further comprise an inject configured to inject gas (e.g., a fuel, an oxidant, or another compound) into the effluent stream within the inlet nozzle. For example, the inlet nozzle may comprise an inject configured to inject a gas composition into the effluent stream conduit. Additionally, or alternatively, each inlet nozzle may comprise an inject configured to inject a gas composition into the inlet conduit. Said inject may be a lance, preferably a lance coaxially arranged within the inlet conduit.
[0020] Additionally, or alternatively, each inlet nozzle may comprise a coaxial flow conduit. The coaxial flow conduit may surround the inlet conduit of the inlet nozzle. The coaxial flow conduit may be an annular conduit (i.e. provide an annular cross-sectioned flow path). The coaxial flow conduit may have an annular exit orifice. The coaxial flow conduit may be configured to deliver a gas composition that substantially surrounds the effluent gas stream exiting the inlet nozzle. Said gas composition may be a fuel gas. Additionally, or alternatively, each inlet nozzle may comprise a sheath flow conduit. The sheath flow conduit may surround the inlet conduit of the inlet nozzle. The sheath flow conduit may surround the coaxial flow conduit, if present. The sheath flow conduit may be a substantially annular cross-sectioned conduit. The sheath flow conduit may have a substantially annular exit orifice. The sheath flow conduit may be configured to deliver a sheath flow composition that may surround the effluent gas stream exiting the inlet nozzle. The sheath flow composition may comprise, for example, nitrogen and / or air, such as compressed dry air. The sheath flow composition may advantageously reduce the temperature of the inlet nozzle, and reduce the likelihood of the formation of deposits.
[0021] Preferably, the inlet nozzles of the inlet head assembly may be swept inlet nozzles. Swept inlet nozzles may be defined as the inlet nozzles as set out in WO 2021 / 245371 A1 , which is incorporated herein by reference.
[0022] The effluent gas stream may be conveyed from process tool. The composition of the effluent gas stream may differ between the inlet nozzles, or it may be substantially the same. It will be appreciated that the composition of the effluent gas stream may depend on the process occurring in the process tool, and may vary over time. The effluent gas stream may include one or more fuel gas compositions configured to aid combustion. The effluent gas stream may include a carrier gas configured to maintain forward flow of fluid through the inlet nozzles.
[0023] The ignition nozzle may be configured to ignite the burner element. The ignition nozzle may be configured to provide point ignition for the burner element. The ignition nozzle may be a separate component to the burner element. The ignition nozzle may be arranged within the head plate adjacent to the burner element. In some embodiments, the ignition nozzle may comprise a pilot flame that is configured to ignite the burner element. The pilot flame of the ignition nozzle may be ignited by a spark generator.
[0024] The inlet nozzles may be arranged adjacent to the burner element.
[0025] The fuel gas composition may be conveyed into the combustion chamber by the burner element at a rate of from about 8 Ipm to about 40 Ipm. The flow rate of the fuel gas composition into the combustion chamber may be fixed or may be variable during operation. In some embodiments, the fuel gas composition may comprise one or more hydrocarbon and an oxidant. In an example, the fuel gas composition may comprise a mixture of a hydrocarbon and air. The hydrocarbon may methane or propane. It will be appreciated that the fuel gas composition is not limited to these examples. In some embodiments, the standing flame may be lit throughout the duration of operation. In other words, whenever an effluent gas stream is conveyed through an inlet nozzle into the combustion chamber, the standing flame may be lit.
[0026] The burner element may be configured to simultaneously initiate the combustion of the effluent gas stream through all of the inlet nozzles. Each of the inlet nozzles may be ignited directly from the burner element. In contrast, in inlet head assemblies of the prior art, an ignition source (e.g. pilot) may ignite the a single nozzle, which may light the other nozzles via chain ignition. Alternatively, some abatement apparatus of the prior art may have a separate burner arranged downstream of the inlet head assembly configured to ignite the inlet nozzles. This may be undesirable as it is an additional component within the abatement apparatus.
[0027] Advantageously, the present invention may reduce the fuel requirements of the inlet head assembly in comparison with inlet heads of the prior art. The burner element may provide a more efficient ignition mechanism. Each of the inlet nozzles may be ignited directly from the burner element. The inlet head assembly may provide a simple design with relatively few components, enabling easier maintenance. Additionally, the burner element of the present invention may be integrated within the inlet head assembly, rather than being a separate component.
[0028] The inlet nozzles may be arranged about the outer circumference of the burner element. The inlet nozzles may be arranged substantially evenly about the outer circumference of the burner element. The distance between each inlet nozzle and the burner element may be substantially uniform. The inlet nozzles may be arranged in a substantially circular arrangement about the burner element.
[0029] Additionally, or alternatively, each of the inlet nozzles may be arranged to extend through the head plate substantially parallel with a central axis of the inlet head assembly. Preferably, the main direction of flow of the effluent gas stream exiting each of the inlet nozzles may be substantially parallel to the effluent gas stream exiting the other effluent gas streams. The inlet nozzles may be substantially configured to be oriented substantially vertically when in use.
[0030] Advantageously, the present invention may allow for simultaneous ignition of all of the inlet nozzles via the burner element, even when the inlet nozzles are arranged substantially in parallel with respect to each other. Typically, the inlet head assembly may comprise from about 2 to about 12 inlet nozzles. Preferably, the inlet head assembly may comprise from about 4 to about 8 inlet nozzles. For example, the inlet head assembly may comprise 6 inlet nozzles. Each inlet nozzle may be substantially the same.
[0031] Typically, the burner element may be arranged on the central axis of the inlet head assembly. The burner element may be arranged on the central axis of the head plate. The burner element may be an annular burner element. The burner element may be arranged such that a central axis of the burner element is coaxial with the central axis of the inlet head assembly and / or the central axis of the head plate.
[0032] Typically, the ignition nozzle may be adjacent to the burner element. Preferably, the ignition nozzle may be arranged within the head plate to be angled with respect to the burner element.
[0033] Typically, a surface of the head plate may be configured to define at least a portion of the combustion chamber. Preferably, said surface of the head plate may be substantially planar. Additionally, or alternatively, the surface of the head plate may extend substantially transverse to the direction of flow of the effluent gas stream from an inlet nozzle.
[0034] In a preferred embodiment, a substantially planar inner face of the head plate may define a portion of the combustion chamber. The inlet nozzles may extend through the head plate in a direction that is substantially transverse to the substantially planar inner face. The inlet nozzles may extend substantially parallel to each other, and to the central axis of the head plate. The burner may be aligned with the central axis of the head plate.
[0035] Typically, the burner element may comprise a distribution chamber within the head plate. The burner element may further comprise a fuel supply port. The fuel supply port may be configured to convey the fuel gas composition into the distribution chamber. The burner element may further comprise an outlet port configured to convey the fuel gas composition from the distribution chamber into the combustion chamber.
[0036] The outer wall of the distribution chamber may be defined by the head plate. Preferably, the distribution chamber may be plenum. The plenum may be a generally toroidal plenum. Such embodiments may provide a passage through the centre of the generally toroidal plenum. The passage may be coaxial with the central axis of the inlet head assembly. The passage may enable feedthrough of, for example, wiring or a drive shaft. In an embodiment, a drive shaft of a scraper may pass through the passage of the generally toroidal plenum. The scraper may be configured to scrape deposits from the inner surface of the head plate to prevent build-up.
[0037] The distribution chamber may be connected to a plurality of fuel supply ports. Alternatively, the distribution chamber may be connected to a single fuel supply port. The fuel supply port(s) may be arranged at or towards a first end of the distribution chamber. The outlet port may be arranged at or towards a second end of the distribution chamber, which may be opposite the first end. The distribution chamber may disperse the fuel gas composition to provide a more even flow of fuel gas composition throughout the entire outlet port, regardless of the position of the fuel supply port(s).
[0038] Typically, the outlet port of the burner element may be substantially annular. Preferably, the substantially annular outlet port may be configured to produce a ring- shaped standing flame. It will be appreciated that the substantially annular burner element conduit may be circular, oval, square, or another cross-section. It will be appreciated that the shape of the substantially annular burner element may depend on the arrangement of the inlet nozzles. The substantially annular burner element may be continuous or discontinuous. The substantially annular burner element may be functionally continuous in the sense that it produces a substantially continuous standing flame.
[0039] The annular outlet port may be arranged about the central axis of the head plate. The annular outlet port may be defined by an inner surface and an outer surface. The inner surface and outer surface may extend substantially parallel to each other. The inner surface may be defined by a component of the burner element. The outer surface may be defined by a component of the burner element, or by a surface of the head plate.
[0040] In a preferred embodiment, the burner element may comprise a generally tubular outer wall, and a generally tubular inner wall. The generally tubular outer wall and generally tubular inner wall may be arranged substantially coaxially. The generally tubular outer wall may be arranged radially outside the generally tubular inner wall. The gap between the generally tubular outer wall and the generally tubular inner wall may define the annular outlet port. The gap between the generally tubular outer wall and the generally tubular inner wall may be substantially uniform about the circumference of the annular outlet port. The gap may be configured to convey fuel gas composition into the combustion chamber. By way of example, the size of the gap measured in a radial direction, may be from about 0.5 mm to about 5 mm, preferably about 1 mm.
[0041] In some embodiments, the outlet port may be castellated to define a plurality of subports through which the fuel gas composition is conveyed into the combustion chamber. Preferably, the outlet port may be annular and castellated. For the purposes of the present invention, the outlet port being castellated may be defined as comprising one or more castellations (i.e. protrusions) extending across the outlet port.
[0042] The castellated outlet port may comprise from about 2 to about 12 sub-ports. Preferably, the castellated outlet port may comprise from about 4 to about 8 sub-ports. For example, the castellated outlet port may comprise 6 sub-ports. Preferably the number of sub-ports may equal the number of inlet nozzles of the inlet head assembly.
[0043] Each castellation may extend substantially across the gap defining the outlet port, preferably the across the entire width of the gap defining the outlet port. The castellations may be arranged about at least part of the circumference of the annular outlet port. Preferably, the castellations may be arranged about at least half of the circumference of the annular outlet port. More preferably, the castellations may be arranged about the entire circumference of the annular outlet port.
[0044] In embodiments wherein the annular outlet port is defined by a generally tubular inner wall and a generally tubular outer wall, the generally tubular inner wall and / or the generally tubular outer wall may define the castellations. In an embodiment, the generally tubular inner wall may comprise a radially outwardly extending flange. The generally tubular outer wall may comprise castellations extending substantially longitudinally to meet the radially outwardly extending flange.
[0045] The sub-ports may be regularly spaced of the castellated outlet port. The sub-ports of the castellated outlet port may be arranged to align with the positions of the inlet nozzles about the central axis of the head plate. Advantageously, a castellated outlet port may reduce fuel usage of the burner element. Additionally, the castellated outlet port may allow for a targeted standing flame to be produced, which may aid in igniting the inlet nozzle(s).
[0046] Typically, the annular outlet port may be configured to convey the fuel gas composition into the combustion chamber in a direction that is substantially parallel to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle. In such embodiments, the standing flame may extend substantially parallel to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle. The standing flame may extend substantially parallel to the central axis of the head plate. The standing flame may extend substantially perpendicular to the inner surface of the head plate defining a portion of the combustion chamber.
[0047] In such embodiments, the generally tubular inner wall and generally tubular outer wall may extend substantially parallel to the central axis of the head plate.
[0048] Alternatively, the annular outlet port may be configured to convey the fuel gas composition into the combustion chamber in a direction that is substantially perpendicular to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle. In such embodiments, the standing flame may extend substantially perpendicular to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle. The standing flame may extend substantially perpendicular to the central axis of the head plate. The standing flame may extend substantially parallel to the inner surface of the head plate defining a portion of the combustion chamber. The standing flame may extend substantially radially outwardly from the burner element.
[0049] In such embodiments, the generally tubular inner wall may comprise a generally radially outwardly extending flange configured to direct the fuel gas composition generally radially outwardly as it exits the outlet port.
[0050] Alternatively, the annular outlet port may be configured to convey the fuel gas composition into the combustion chamber in a direction that is from about 5° to about 85° relative to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle. Preferably, the annular outlet port may be configured to convey the fuel gas composition into the combustion chamber in a direction that is from about 20° to about 70° relative to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle. Advantageously, the present invention may provide a variety of different configurations of outlet port, enabling the direction of the standing flame to be selected. This may increase the number of applications (e.g. effluent gas compositions) for which the inlet head assembly may be used.
[0051] Typically, the burner may be configured to convey the fuel gas composition in a generally radially outward direction.
[0052] The inlet head assembly may further comprise a thermocouple. In some embodiments, the inlet head assembly may comprise a plurality of thermocouples. The thermocouple may extend through the head plate. The thermocouple may be configured to monitor the temperature within the combustion chamber. The thermocouple may be connected to a controller. The controller may be configured to stop the operation of the abatement apparatus if the temperature registered by the thermocouple exceeds or falls below a threshold value. In some embodiments, the controller may be configured to stop the operation of the abatement apparatus if the temperature registered by the thermocouple is outside of an operating temperature range. The threshold value and / or operating temperature range may depend on a range of factors. By way of example, factors may include the configuration of the inlet head assembly, the composition of the effluent gas stream, and / or the process step occurring in the process tool.
[0053] The inlet head assembly may further comprise a scraper. The scraper may be configured to scrape deposits from the inner surface of the head plate to prevent buildup.
[0054] In a further aspect, the present invention provides an abatement apparatus comprising a combustion chamber with an inlet head assembly according to any aspect or embodiment described herein capping said combustion chamber.
[0055] The abatement apparatus may comprise an abatement chamber. The abatement chamber may be a combustion chamber. The abatement apparatus may be an Atlas as produced by Edwards limited. The combustion chamber may be configured to treat, process or abate the effluent gas stream. The abatement apparatus may comprise a weir stage. The weir stage may comprise a conduit through which the gas may flow, wherein the conduit may be surrounded by liquid curtain (i.e. a weir). The liquid may be water, or a scrubbing liquid.
[0056] In embodiments, the abatement apparatus may comprise a quench stage. The quench stage may comprise one or more nozzles configured to spray a quench liquid in a direction transverse to the main flow direction of the gas to be scrubbed, which is conveyed through said quench liquid.
[0057] The abatement apparatus may comprise a wet scrubber. Preferably, the wet scrubber may be arranged downstream of the combustion chamber and the weir stage is arranged between the combustion chamber and the wet scrubber.
[0058] In some embodiments, the quench stage may be arranged downstream of the weir stage.
[0059] Advantageously, the quench stage and / or weir stage may cool the gases as they pass between the combustion chamber and the wet scrubber tower.
[0060] In a further aspect, the present invention provides a method for abating an effluent gas stream. The method comprises the steps of: a. providing an abatement apparatus according to an aspect or embodiment described herein, b. conveying a fuel gas composition into the combustion chamber through the burner element; c. igniting the fuel gas composition via the ignition nozzle to provide a standing flame; d. conveying the effluent gas stream into the combustion chamber through one or more of the inlet nozzles, wherein combustion of the effluent gas stream is initiated by the standing flame. Step (b) of the method may further comprise conveying the fuel gas composition into the distribution chamber through the fuel supply port, then conveying the fuel gas composition from the plenum into the combustion chamber through the substantially annular outlet port.
[0061] For the avoidance of doubt, all aspects and embodiments described herein may be combined, mutatis mutandis.
[0062] Brief Description of Figures
[0063] Preferred features of the present invention will now be described, by way of example, with reference to the accompanying figures, in which:
[0064] Figure 1 illustrates a cross-sectional view of an inlet head assembly according to an embodiment of the present invention;
[0065] Figure 2 illustrates an exploded view of a portion of an inlet head assembly according to an embodiment of the present invention;
[0066] Figure 3 illustrates an exploded view of a burner element of an inlet head assembly according to an embodiment of the present invention;
[0067] Figures 4A-B illustrate views of a base of an inlet head assembly according to an embodiment of the present invention;
[0068] Figure 5A-C illustrates cross-sectional views of a portion of burner elements for inlet head assemblies in accordance with embodiments of the present invention.
[0069] Figure 6 shows a flow chart of a method in accordance with an embodiment of the present invention.
[0070] Detailed Description
[0071] Figure 1 shows a cross-sectional view of an inlet head assembly (1) in accordance with an embodiment of the present invention. The inlet head assembly (1 ) is suitable for capping a combustion chamber of an abatement apparatus (not shown).
[0072] The inlet head assembly (1 ) comprises a head plate (2). When in use, an inner face (6) of the head plate (2) provides a portion of the internal surface of the combustion chamber. The head plate (2) is substantially cylindrical. A central axis (A) of the head plate (2) is configured to be coaxial with a central axis of the combustion chamber. The head plate (2) comprises a flange configured to be coupled to the housing (not shown) that defines the remainder of the combustion chamber.
[0073] The inlet head assembly (1 ) further comprises a plurality of inlet nozzles (3) extending through the head plate. In this embodiment, the inlet head assembly comprises six inlet nozzles (3). However, owing to the cross-sectional view, only two inlet nozzles (3) are visible. Each inlet nozzle (3) is configured to convey an effluent gas stream into the combustion chamber of the abatement apparatus. Each inlet nozzle (3) is arranged within, and extends through, the head plate (2) of the inlet head assembly (1 ). Each inlet nozzle (3) may extend through the head plate to or near to the inner face (6) of the head plate (2). Further features of the inlet nozzles (3) can be found elsewhere herein.
[0074] The inlet head assembly (1 ) further comprises a burner element (5) arranged within the head plate (2) between the inlet nozzles (3). In this embodiment, the burner element (5) is arranged coaxially with a central axis of the head plate (2). The inlet nozzles (3) are arranged through the head plate (2) about the burner element (5). The burner element (5) is configured to convey a fuel gas composition into the combustion chamber. In this arrangement, a surface of the burner element (5) defines a portion of the combustion chamber of the abatement apparatus when in use.
[0075] The inlet head assembly (1 ) further comprises an ignition nozzle (4) extending through the head plate (2). The ignition nozzle (4) is configured to ignite the fuel gas composition exiting the burner element (5) to provide a standing flame. Said standing flame is configured to initiate combustion of the effluent gas stream exiting the inlet nozzles (3). The ignition nozzle (4) is configured to provide point ignition for the burner element. In this embodiment, the ignition nozzle (4) extends through the head plate (2) at an angle relative to the central axis (A) of the head plate (2).
[0076] The burner element (5) comprises a distribution chamber (7) within the head plate (2). In this embodiment, the distribution chamber (7) is a generally toroidal plenum. The burner element (5) comprises a fuel supply port (8). The fuel supply port (8) is configured to convey the fuel gas composition into the distribution chamber (7). The burner element (5) further comprises an outlet port (9) configured to convey the fuel gas composition from the distribution chamber (7) into the combustion chamber. The outlet port (9) of the burner element (5) is annular. The outlet port (9) is coaxial with the central axis (A) of the head plate (2).
[0077] In this embodiment, the inlet head assembly (1 ) further comprises a scraper (10). The scraper (10) is configured to rotate. A blade (11 ) of the scraper (10) is configured to remove deposits from the inner surface of the head plate to prevent build-up.
[0078] In this embodiment, the inlet nozzles (3) all extend through the head plate (2) substantially parallel to the central axis (A) of the head plate. All of the inlet nozzles (3) are arranged to extend through the head plate (2) substantially parallel with respect to each other.
[0079] Figure 2 shows an exploded view of a portion of an inlet head assembly according to an embodiment of the present invention. The inlet head assembly may be part of that as illustrated in Figure 1 .
[0080] In this embodiment, the head plate (2) may comprise a plurality of interconnected components. The head plate (2) comprises a first portion (12), a second portion (13), and a third portion (14). The first portion (12) comprises the inner face (6) that provides a portion of the internal surface of the combustion chamber. The first portion (12) is configured to be arranged within the third portion (14). The first portion (12) may be an insulation body. The second portion (13) is located between the first portion (12) and third portion (14). The second portion (13) may be an insulation gasket. The third portion (14) comprises the flange (7) configured to be coupled to the housing (not shown) that defines the remainder of the combustion chamber.
[0081] When assembled, the head plate (2) comprises conduits (15) extending therethrough. The conduits (15) are each configured to receive an inlet nozzle (3) of the inlet head assembly during use. In this case, the head plate (2) comprises six conduits (15), as the inlet head assembly comprises six inlet nozzles.
[0082] In this embodiment, the head plate (2) further comprises a burner element (5) received therein.
[0083] Figure 3 illustrates an exploded view of a burner element (5) of an inlet head assembly according to an embodiment of the present invention. The burner element (5) may be that as shown in Figures 1 and 2. In this embodiment, the burner element (5) comprises a plurality of interconnected components. The burner element (5) comprises a frame component (16). The frame component (16) is configured to define the distribution chamber (7). The frame component (16) comprises a plurality of interconnected hollows (17) configured to reduce the weight of the component. The frame component (16) further comprises a pair of fuel supply ports (8). The fuel supply ports (8) are configured convey the fuel gas composition into the distribution chamber (7) during use.
[0084] The burner element (5) further comprises a sheath component (18). The sheath component (18) is configured to be connected to the frame component (16). An inner surface of the sheath component, not visible in this figure, defines the outer wall of the outlet port of the burner element (5).
[0085] The burner element (5) further comprises an inner component (19). The inner component (19) is configured to be connected to the sheath component (18). The outer diameter of the inner component (19) is smaller than the diameter of the inner surface of the sheath component (18), providing a radial gap therebetween. The outlet port of the burner element is defined by the gap between the inner component (19) and the sheath component (18). The burner element (5) further comprises a shim (20) configured to sit axially between the sheath component (18) and the inner component (19).
[0086] The design of the shim (20) may be selected to improve the stability of the standing flame at the outlet of the burner element (5) during use. For example, the thickness of the shim (20) may be selected to control the flow of fuel gas through that region of the burner element.
[0087] The burner element (5) further comprises a plug (21 ). The plug (21 ) is configured to be received within the inner component (19). The plug (21 ) is configured to provide an insulating barrier. The plug (21 ) may comprise a ceramic material.
[0088] The burner element (5) further comprises gaskets (22) configured to seal interfaces between components.
[0089] Figures 4A-B illustrate views of a base of an inlet head assembly according to an embodiment of the present invention. Figure 4A shows a first embodiment. The burner element (23) comprises an annular outlet port (24). The annular outlet port (24) is configured to convey the fuel gas composition into the combustion chamber. The burner element (23) is centrally arranged on an inner face (25) of the head plate (26).
[0090] The inner face (25) of the head plate (26) is configured to provide a portion of the surface defining the combustion chamber. The inner face (25) of the head plate (26) may comprise a ceramic material. The head plate (26) further comprises a plurality of conduits (27) extending therethrough. An inlet nozzle (28) is arranged in each of the conduits (27). The head plate (26) further comprises a channel (29) configured to receive an ignition nozzle.
[0091] When in use, the ignition nozzle ignites the fuel gas composition exiting the outlet port (24) of the burner element (23). This produces a standing flame (30). The standing flame (30) is configured to ignite the effluent gas stream entering the combustion chamber through the inlet nozzles (28). In this embodiment, because of the arrangement of the outlet port (24) of the burner element, the standing flame (30) extends generally radially outwardly from the outlet port (24). The standing flame (30) extends substantially parallel to the inner face (25) of the head plate (26). The standing flame (30) extends substantially perpendicular to the main direction of flow of the effluent gas stream exiting the inlet nozzles (28). In this embodiment, the standing flame (30) extends about the entire circumference of the outlet port (24).
[0092] Figure 4B shows a second embodiment, having many of the same features as the embodiment of Figure 4A, for which the same reference numerals will be used.
[0093] In this embodiment, the annular outlet port (31 ) is castellated to define a plurality of sub-ports (32) through which the fuel gas composition is conveyed into the combustion chamber. The sub-ports (32) are arranged about the circumference of the annular outlet port (31 ). The sub-ports (32) are substantially evenly spaced about the circumference of the annular outlet port (31 ). The sub-ports (32) are arranged to align with the positions of the inlet nozzles (28) about the central axis of the head plate (26)
[0094] A standing flame (33) may be present at each sub-port (32) during use. Each standing flame (33) is configured to ignite an effluent gas stream entering the combustion chamber through a corresponding inlet nozzle. Advantageously, the castellated outlet port (31 ) may reduce the fuel usage of the burner element. Figure 5A-C illustrates cross-sectional views of a portion of burner elements for inlet head assemblies in accordance with embodiments of the present invention.
[0095] Figure 5A shows a cross-sectional view of a portion of a first burner element (34). The first burner element (34) comprises an outlet port (35). The inlet nozzles (not shown) are arranged to convey the effluent gas stream into the combustion chamber in a direction substantially parallel to the central axis (A) of the inlet head assembly.
[0096] In this embodiment, the outlet port (35) is arranged to convey the fuel gas composition into the combustion chamber in a direction (Di) that is substantially parallel to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle. In this embodiments, the standing flame extends substantially parallel to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle. The standing flame may extend substantially parallel to the central axis of the head plate. The standing flame may extend substantially perpendicular to the inner surface (36) of the head plate defining a portion of the combustion chamber.
[0097] Figure 5B shows a cross-sectional view of a portion of a second burner element (37). The second burner element (37) comprises an outlet port (38). The inlet nozzles (not shown) are arranged to convey the effluent gas stream into the combustion chamber in a direction substantially perpendicular to the central axis (A) of the inlet head assembly.
[0098] In this embodiment, the outlet port (38) is arranged to convey the fuel gas composition into the combustion chamber in a direction (D2) that is substantially perpendicular to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle. In this embodiments, the standing flame extends substantially perpendicular to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle. The standing flame may extend substantially perpendicular to the central axis of the head plate. The standing flame may extend substantially parallel to the inner surface (39) of the head plate defining a portion of the combustion chamber.
[0099] Figure 5C shows a cross-sectional view of a portion of a third burner element (40). The third burner element (40) comprises an outlet port (41 ). The inlet nozzles (not shown) are arranged to convey the effluent gas stream into the combustion chamber in a direction substantially perpendicular to the central axis (A) of the inlet head assembly. The outlet port (41 ) is configured to convey the fuel gas composition into the combustion chamber in a direction (D3) that is from about 5° to about 85° relative to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle.
[0100] Figure 6 shows a flow chart of a method in accordance with an embodiment of the present invention.
[0101] The method comprises the steps of: a. Providing an abatement apparatus according to an aspect or embodiment described herein (42). b. Conveying a fuel gas composition into the combustion chamber through the burner element (43). c. Igniting the fuel gas composition via the ignition nozzle to provide a standing flame (44). d. Conveying the effluent gas stream into the combustion chamber through one or more of the inlet nozzles, wherein combustion of the effluent gas stream is initiated by the standing flame (45).
[0102] Reference Key
[0103] 1 . Inlet head assembly
[0104] 2. Head plate
[0105] 3. Inlet nozzle
[0106] 4. Ignition nozzle
[0107] 5. Burner element
[0108] 6. Inner face
[0109] 7. Distribution chamber
[0110] 8. Fuel supply port
[0111] 9. Outlet port
[0112] 10. Scraper
[0113] 11. Blade
[0114] 12. First portion
[0115] 13. Second portion
[0116] 14. Third portion
[0117] 15. Conduit
[0118] 16. Frame component
[0119] 17. Hollow
[0120] 18. Sheath component
[0121] 19. Inner component
[0122] 20. Shim
[0123] 21. Plug
[0124] 22. Gasket
[0125] 23. Burner element
[0126] 24. Outlet port
[0127] 25. Inner face
[0128] 26. Head plate
[0129] 27. Conduit
[0130] 28. Inlet nozzle
[0131] 29. Channel
[0132] 30. Standing flame
[0133] 31 . Outlet port
[0134] 32. Sub-port 33. Standing flame
[0135] 34. First burner element
[0136] 35. Outlet port
[0137] 36. Inner surface 37. Second burner element
[0138] 38. Outlet port
[0139] 39. Inner surface
[0140] 40. Third burner element
[0141] 41 . Outlet port 42. Method step
[0142] 43. Method step
[0143] 44. Method step
[0144] 45. Method step
Claims
Claims1 . An inlet head assembly for capping a combustion chamber of an abatement apparatus, the inlet head assembly comprising: a head plate; a plurality of inlet nozzles extending through the head plate, each inlet nozzle being configured to convey an effluent gas stream into the combustion chamber; an ignition nozzle extending through the head plate; wherein the inlet head assembly further comprises a burner element arranged within the head plate between the inlet nozzles and configured to convey a fuel gas composition into the combustion chamber, and wherein the ignition nozzle is configured to ignite the fuel gas composition exiting the burner element to provide a standing flame, and said standing flame is configured to initiate combustion of the effluent gas stream exiting the inlet nozzles.
2. The inlet head assembly according to claim 1 , wherein the inlet nozzles are arranged about the outer circumference of the burner element and / or wherein each of the inlet nozzles is arranged to extend through the head plate substantially parallel with a central axis of the inlet head assembly.
3. The inlet head assembly according to claim 1 or claim 2, comprising from about 2 to about 12 inlet nozzles, preferably from about 4 to about 8 inlet nozzles, for example 6 inlet nozzles.
4. The inlet head assembly according to any preceding claim, wherein the burner element is arranged on the central axis of the inlet head assembly.
5. The inlet head assembly according to any preceding claim, wherein the ignition nozzle is adjacent to the burner element, preferably wherein the ignition nozzle is arranged within the head plate to be angled with respect to the burner element.
6. The inlet head assembly according to any preceding claim, wherein a surface of the head plate is configured to define at least a portion of the combustion chamber, preferably wherein said surface is substantially planar and / or extends substantially transverse to the direction of flow of the effluent gas stream from an inlet nozzle.
7. The inlet head assembly according to any preceding claim, wherein the burner element comprises a distribution chamber within the head plate, a fuel supply port configured to convey the fuel gas composition into the distribution chamber, and an outlet port configured to convey the fuel gas composition from the distribution chamber into the combustion chamber, preferably wherein the distribution chamber is a plenum.
8. The inlet head assembly according to claim 7, wherein the outlet port of the burner element is substantially annular, preferably wherein the annular outlet port is configured to produce a ring-shaped standing flame.
9. The inlet head assembly according to claim 7 or 8, wherein the outlet port is castellated to define a plurality of sub-ports through which the fuel gas composition is conveyed into the combustion chamber.
10. The inlet head assembly according to claim 8 or 9, wherein the annular outlet port is configured to convey the fuel gas composition into the combustion chamber in a direction that is substantially parallel to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle, or a direction that is substantially perpendicular to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle.11 . The inlet head assembly according to claim 8 or 9, wherein the annular outlet port is configured to convey the fuel gas composition into the combustion chamber in a direction that is from about 5° to about 85° relative to the main direction of flow of the effluent gas stream exiting at least one inlet nozzle, preferably from about 20° to about 70°.
12. The inlet head assembly according to any preceding claim, wherein the burner element is configured to convey the fuel gas composition in a generally radially outward direction.
13. An abatement apparatus comprising a combustion chamber with an inlet head assembly according to any preceding claim capping said combustion chamber.
14. A method for abating an effluent gas stream comprising the steps of: a. providing an abatement apparatus according to claim 13, b. conveying a fuel gas composition into the combustion chamber through the burner element; c. igniting the fuel gas composition via the ignition nozzle to provide a standing flame; d. conveying the effluent gas stream into the combustion chamber through one or more of the inlet nozzles, wherein combustion of the effluent gas stream is initiated by the standing flame.
15. The method according to claim 14, wherein step (b) comprises conveying the fuel gas composition into the distribution chamber through the fuel supply port, then conveying the fuel gas composition from the plenum into the combustion chamber through the substantially annular outlet port.