Flame-based detector with ignition acceleration port

Abstract

The flame base detector (102) comprises a housing (104), a burner (106), a fuel passage (108), an air passage (110), a collector (114), an ignition device (116), an ignition acceleration port (122), and an outlet (128). The ignition acceleration port (122) guides the gas near the ignition device (116), thereby accelerating combustion.

Description

Technical Field

[0001] Cross-reference to Related Applications None applicable

[0002] The present invention generally relates to flame-based detectors and methods for manufacturing and using such detectors.

Background Art

[0003] Flame-based detectors are used to detect the analyte of a sample present in a fluid stream. There are two such detectors: a flame ionization detector (FID; hydrogen flame ionization detector) and a flame photometric detector (FPD).

[0004] The flame ionization detector operates by burning the analyte of the analysis target to form ions. When used in chromatographic analytical equipment, the sample analyte eluting from the separation column is mixed with a combustible gas such as hydrogen and passed through a burner. Air is also introduced around the burner, and when the burner is ignited, a stable flame is formed by the combustion of the fuel and air continuously supplied to the burner. An ion collector such as an electrode is placed downstream of the burner to collect the ions formed in the flame. Also, a measuring instrument is connected to the ion collector to measure the change in the current generated by the ions contacting the ion collector. The generation of these ions is proportional to the concentration of organic species in the sample introduced into the FID.

[0005] Flame photometers operate similarly to flame ionization detectors, but rely more on the chemiluminescence reaction of the test substance than on the ionization reaction. Typically, FPDs are used to detect the presence or absence of sulfur or phosphorus in a sample. Similar to FIDs, FPDs mix the sample with flammable fuel and air in a flame. When the test substance, such as sulfur and phosphorus, burns in the flame, it transforms into a luminescent species. Instead of collecting ions, FPDs collect the light emitted when the test substance luminescents in the flame. FPDs contain photomultiplier tubes (PMTs) that collect the light (photons) emitted when the test substance burns in the flame. This emission from excited species can be used to determine the concentration of the test substance and to quantify the concentration of specific excited species. FPDs often incorporate photomultiplier tubes (PMTs), and a wavelength-selective filter positioned between the FPD's flame and the PMT measures the number of photons and, consequently, the intensity of the light emitted from phosphorus and sulfur-containing compounds.

[0006] U.S. Patent No. 4,346,055 discloses a flame ionization detector in which an ignition device is mounted above the collector body downstream of the jet. Ignition occurs when the hydrogen-air gas reaches a hot filament at a suitable concentration. However, the device is inconvenient because the FID exhaust gas contains corrosive substances such as sulfides from the analytical sample, which can corrode the ignition device or its components (such as the filament), and such corrosion can make ignition of the burner more difficult.

[0007] One example of a current method for igniting a flame-based detector involves closing the channel supplying makeup gas to the detector, opening the hydrogen channel, and opening the air channel. Burner ignition can be complicated by various device states or procedures. Furthermore, the difficulty is exacerbated because the operator is not usually aware of all the conditions present during an ignition attempt. If the device itself is in a state that is not suitable or has little margin for ignition, the operator may need to repeat ignition attempts to succeed, and since they are not aware of the reasons for the failures, the ignition procedure can become significantly longer and more difficult than desired.

[0008] This can become even more problematic when attempting to reignite the detector in the event of flame extinction during continuous chromatograph operation. For example, if the flame goes out during analysis, immediate reignition is necessary to quickly restart the detector; otherwise, a significant portion of the analysis results may be compromised or lost. Therefore, there is a need to improve the reliability and ease of flame ignition in flame-based detectors. There is also a need to reduce maintenance and extend the lifespan of such detectors. [Overview of the project]

[0009] In one aspect of the present invention, a flame-based detector is provided. This flame-based detector comprises a housing, a burner disposed in the upstream region of the housing, a fuel passage for supplying combustible fuel to the burner, an air passage for supplying air to the burner, and an ion collector or a photon collector. The flame-based detector also comprises an ignition device in the downstream region of the housing, and an ignition acceleration port located near the ignition device and configured to direct an ignition-accelerating gas toward the ignition device.

[0010] In another embodiment, a detection system is provided, comprising a flame-based detector as described herein, a measuring instrument configured to measure a signal from a collector, and a controller in signal communication with one or more other components of the detection system.

[0011] In yet another embodiment, a method for igniting a flame-based detector is provided. This method includes supplying fuel and air to the detector so that the fuel and air flow to an ignition device, flowing an ignition-promoting gas toward the ignition device of the detector, and igniting a flame in the flame-based detector.

[0012] The above and other features and advantages of the device and method will become apparent from the following detailed description, in conjunction with the attached claims. [Brief explanation of the drawing]

[0013] [Figure 1] This is a cross-sectional view of a typical embodiment of a flame-based detector. [Figure 2] This is a diagram of a typical embodiment of a detection system equipped with a flame-based detector. [Figure 3] This figure shows one embodiment of a flame-based detector having an ignition-promoting gas conduit and an ignition-promoting port that communicates with the fluid. [Modes for carrying out the invention]

[0014] This instruction will be best understood when read in conjunction with the attached drawings, as detailed below. These features are not necessarily drawn to actual size. For practical purposes, the same reference number represents the same feature.

[0015] The flame-based detector includes an ignition-enhancing port, which is mounted in a housing and configured to blow an ignition-enhancing gas onto the igniter. The ignition-enhancing port intermittently blows the gas onto the igniter, thereby increasing the contact area between the hydrogen-air mixture and the hot filament. By increasing the contact area between the hydrogen-air mixture and the hot filament, the mixture can be ignited by the heat from the igniter, provided that the corrosion and / or deformation of the igniter (e.g., the filament) is minor. The flame-based detector offers several advantages, including an increased probability of successful ignition and / or an improved ignition success rate throughout the detector's entire lifespan. Furthermore, because reliable and / or rapid ignition can be achieved despite corrosion or deformation, the lifespan of the igniter is extended, reducing the frequency of igniter maintenance and / or replacement.

[0016] Figure 1 shows a cross-section of one embodiment of a flame-based detector according to the present invention. More specifically, Figure 1 shows an exemplary flame ionization detector (FID; hydrogen flame ionization detector) 102, but it is understood that a flame photometric detector (FPD) may also have many of the same components. The flame ionization detector comprises a housing 104 having an upstream region 104a and a downstream region 104b. The housing 104 may comprise one or more components, such as two or more liquid-tightly connected tubes. Suitable materials for the housing include metals such as stainless steel and titanium, alloys, ceramics, or combinations thereof.

[0017] The flame base detector also includes a burner 106 located in the upstream region of the housing. The burner may be made from a single, solid material or from an assembly of burner components. The burner may be manufactured by machining, 3D printing, or casting. The material that can be used to manufacture the burner may be any metal, alloy, or polymer that is wear-resistant and can withstand high temperatures, such as about 200°C to about 1000°C. For example, this material may be a high-performance alloy containing elements such as chromium, manganese, nickel, copper, titanium, molybdenum, silicon, columbium, tantalum, carbon, phosphorus, sulfur, nitrogen, iron, or a combination thereof. For example, the high-performance alloy may be a NITRONIC alloy, commercially available from HP Alloys, Tipton, Ind.

[0018] The flame-based detector includes a fuel channel 108 for supplying combustible fuel to the burner. In most cases, the sample after it has left the column during analysis also flows through the fuel channel 108, so the fuel channel is not considered to be limited to a fuel-only channel. The fuel can be hydrogen or a mixture of hydrogen and a diluent. The fuel channel 108 can be integrated with the burner 106 as shown in Figure 1, or it may be a separate component. The flame-based detector also includes an air channel 110 for supplying air to the burner. Similarly, the air channel 110 can be integrated with the burner 106, or it may be a separate component. The air and fuel mix in the burner 106 to produce a flame.

[0019] The flame-based detector comprises a signal collector extending from an upstream to a downstream region within the housing. The signal collector may be an ion collector 114 in an FID or a photon collector in an FPD. The ion collector is typically positioned adjacent to the flame generated by the ignition of an air-fuel mixture in a burner. The ion collector may comprise one or more polarization electrodes that collect ions generated as the sample passes through the flame. The collection of ions generates an ionization current. This current is proportional to the rate at which carbon atoms enter the flame and therefore serves as a measure of the hydrocarbon concentration in the sample. The ion collector is electrically coupled to a circuit extending through the housing so that signals can be transmitted. These concentrations and related information may be stored and analyzed separately, or output to a display device such as a measuring instrument.

[0020] In some embodiments, the FID comprises a pair of positive and negative electrodes used to provide a potential difference in the FID. Typically, the burner acts as the positive electrode, and the collector, located above the flame, is the negative electrode. Thus, ions are attracted to the collector, and when they collide with it, they induce a measurable current. The measurable current roughly corresponds to the proportion of reduced carbon atoms in the flame. The detector's response is determined by the number of carbon atoms (ions) that collide with the detector per unit time. This makes the detector useful because it is more sensitive to mass than to concentration, as the detector's response is not significantly affected by changes in the carrier gas flow rate.

[0021] In some embodiments, the ion collector is made of stainless steel, titanium, tungsten, palladium, platinum, or a combination thereof. The ion collector can have any suitable size or shape, including but not limited to tubes, cylinders, plates, etc.

[0022] Flame-based detectors typically include an ignition device used for initial ignition and re-ignition of the flame. The flame-based detector includes an ignition device 116 in the downstream region 104b of the housing. As the ignition device 116, any of a variety of ignition devices capable of causing combustion of the combustible fuel supplied to the burner may be possible. In some embodiments, the ignition device includes a filament such as a NiCr wire that can be heated to a temperature sufficient to ignite the fuel / air mixture. The filament can be electrically connected to a power source, which may be the same as or different from the power source of other components of the detector. The ignition device can be present within the housing or may be present within an ignition device mounting member 118 attached to the housing 104.

[0023] Typically, an ignition device such as a filament is attached downstream of the burner in the housing 104. In the burner, when hydrogen appears, it usually begins to mix with the air introduced ambiently. The gas burns when it reaches the high-temperature filament in the downstream region of the housing. Generally, the normal gas flow rate is such that the resulting flame front cannot propagate at a speed sufficient for it to move upstream towards the burner. Thus, the flow of one or more of the gases is reduced. When the air-to-hydrogen ratio becomes sufficiently small, the flame front propagates at a speed large enough to move upstream in the low-speed gas and ignites the burner. At this point, the flow of gases such as air increases to a speed desirable for the analysis and operation of the flame-based detector. When the burner is ignited, the flame generally stays in place. However, if it goes out for some reason, the process is repeated.

[0024] The flame photometric detector is ignited in the same way as the flame ionization detector. However, in the FPD, since a flame containing substantially more hydrogen than air is used, usually, in order to prevent an explosion during flame ignition, ignition is assisted by increasing the air flow while keeping the hydrogen flow constant.

[0025] In a flame-based detector, if the user desires to ignite the burner 106 of the detector 102, a fuel such as hydrogen is flowed into the housing through the fuel passage, typically reaching the desired level in a few seconds. Air is then flowed into the housing. The fuel-air mixture 125 passes through the collector 114 and then flows to the ignition device 116 of the detector 102. If the ignition device 116 is hot enough and a sufficient amount of the fuel-air mixture 125 is in contact, the combustion of the fuel-air mixture 125 produces a blast 117, which can travel to the burner 106.

[0026] In some embodiments, the flame-based detector includes an ignition promotion port 122. As shown in FIG. 1, the ignition promotion port 122 is disposed within the housing 104 of the detector 102 and is spaced apart and arranged relative to the ignition device to supply a gas that promotes ignition of the fuel / air mixture by the ignition device 116. When ignition is desired, a combustible fuel is flowed to the burner. Air is likewise flowed, and as the air flow gradually increases, the concentrations of hydrogen and air reach a range where ignition of the fuel / air mixture becomes easy, while in the case of corrosion or deformation of the ignition device, ignition is not easy. When the concentrations are within that range, the ignition promotion gas can be blown against the fuel / air mixture gas to contact the highest temperature filament possible by blowing the ignition promotion gas against the fuel / air mixture gas to the ignition device. Since the ignition promotion port 122 is open, the ignition promotion gas 124 flows into the housing 104. In some embodiments, the ignition promotion gas is flowed while the fuel / air mixture is being supplied to the detector. For example, by opening the ignition promotion port, the ignition promotion gas can start flowing into the housing. After a desired period, the air flow is changed to a specific value set by the user, and the ignition promotion port is closed. In some embodiments, the ignition promotion gas continues to be flowed or is flowed before the fuel / air mixture is supplied to the detector. For example, the ignition promotion gas 124 can be flowed into the housing 104 before the fuel / air mixture is supplied to the detector and / or before ignition is desired. In such embodiments, the ignition promotion gas 124 can be flowed at a pressure and / or flow rate desirable for promoting ignition, or can be flowed at a reduced pressure and / or flow rate and then increased when ignition is desired. The reduction in the pressure and / or flow rate of the ignition promotion gas 124 can be achieved by partially closing the ignition promotion port 122 or a valve fluidly connected to the ignition promotion port 122.

[0027] The ignition-promoting gas may be fuel and / or air, another combustible gas, or another non-combustible gas that promotes ignition by pushing the fuel and / or air toward the ignition device. The ignition-promoting gas causes the fuel / air mixture to be blown toward the ignition device and / or increases the amount or proportion of the fuel / air mixture in contact with the ignition device.

[0028] The ignition accelerator port may have any suitable size or shape. In some embodiments, the ignition accelerator port is circular or oval, and the diameter or longest dimension of the ignition accelerator port is about 0.3 mm to about 1.0 mm. In some embodiments, the pressure of the ignition accelerator gas is about 5 psi to about 80 psi, but can be increased or decreased based on the pressure of the fuel / air mixture or other considerations. In some embodiments, the flow rate of the ignition accelerator gas is at least about 18 ml / min, at least about 24 ml / min, or at least about 36 ml / min, or about 180 ml / min or less, about 135 ml / min or less, or about 90 ml / min or less. It is also conceivable that any combination of the above minimum and maximum values ​​may form a range. It is also conceivable that the flow rate may be increased or decreased based on the exhaust gas flow or other considerations.

[0029] In some embodiments, the ignition accelerator port 122 is located directly opposite the igniter 116, or downstream or upstream of the igniter (e.g., about 1 mm to about 25 mm upstream or downstream). The ignition accelerator gas can flow directly toward the igniter or at an angle. The igniter and the ignition accelerator port may be located on opposite sides of the housing (for example, if the inside of the housing is substantially circular, the igniter may be located at 0° on the inner circumference of the housing, and the ignition accelerator port may be located at about 180°, about 90°, about 135°, about 165° to about 195°, or at other angles). In some embodiments, the flame base detector has one, two, three, four or more ignition accelerator ports. If there are multiple ignition accelerator ports, they may be located uniformly on the inner circumference of the housing (e.g., about 90°, about 180°, and about 270°) or unevenly.

[0030] Any gas, preferably a non-flammable gas, can be used as the ignition-promoting gas. In some embodiments, the ignition-promoting gas is air. In such embodiments, the ignition-promoting gas port can be fluidly connected to the same air source as the burner or to a different air source. In some embodiments, the ignition-promoting gas is air, carbon dioxide (CO2), nitrogen (N2), argon (Ar), xenon (Xe), nitrous oxide (N2O), helium (He), hydrogen (H), or chlorofluorocarbon (CFC), and the ignition-promoting port can be fluidly connected to a source of such a gas.

[0031] The ignition-enhancing port can be configured to facilitate a laminar flow of ignition-enhancing gas toward the igniter. The flame base detector may also have other features for forming or assisting in the formation of the ignition-enhancing gas flow. In some embodiments, the flame base detector comprises one or more flame-expanding plates adjacent to the ignition-enhancing port. The flame-expanding plates can be positioned to direct or shape the flow of ignition-enhancing gas exiting the port, and / or to confine or redirect the ignition-enhancing gas toward the igniter.

[0032] In some embodiments, the flame-based detector includes an outlet 128 in the downstream region 104b of the housing 104 for discharging exhaust gas from the housing 104. The outlet 128 may include an opening that allows the exhaust gas to flow out of the housing and may comprise one or more components such as a valve, seal, mounting member, or adapter. In some embodiments, the outlet 128 includes a flame arrestor that can be press-fitted into the opening in the downstream region of the housing. A typical flame arrestor has sufficient thermal conductivity to remove heat from a flame attempting to move through a narrow passage. The detector may also include an exhaust pipe mounting member to facilitate the connection of piping, such as a conduit for collecting exhaust gas.

[0033] Detection system In another embodiment, the disclosure provides a detection system comprising a flame-based detector and one or more connecting components. For example, the detection system may include a controller operably connected to the flame-based detector and controlling the flow of a sample, combustible fuel, and / or air by the operation of one or more valves between each gas source and the flame-based detector. The detection system may further include valves, flow regulators, conduits, and other components between each gas source and the flame-based detector. As an example, one embodiment of the detection system includes various gas sources, fluid delivery components, power supplies and / or voltage differential sources, as well as various measuring instruments and sensors. In the use herein, a gas source includes a gas-filled container (such as a canister or tank), which may or may not be pressurized. For example, a tank of pressurized hydrogen gas can be used as a fuel source. The gas source may also include a panel connected to a gas distribution system as commonly found in a laboratory. The sample source is generally a channel from a chromatography column, or includes such a channel.

[0034] Figure 2 shows one embodiment of a detection system 201 comprising a flame-based detector 202 having a housing 204, a burner 206, and an ion collector 214. A fuel supply conduit 208 supplies combustible fuel from a fuel source 254 to the burner 206, and an air supply conduit 211 supplies air from an air source 256 to the burner 206. When a flame 212 is ignited above the burner 206, ions pass through the ion collector 214, which is electrically connected by one or more electrical contacts extending through the housing 204 to a measuring instrument 242 (such as a high-impedance picometer) capable of measuring the ions collected by the collector 214. Exhaust gas from the collector can be discharged from the housing 204 through an outlet 228 and, optionally, a flame arrestor 229.

[0035] Furthermore, the ignition device 216 is mounted on the inner wall of the housing 204 (or can be located in a recess / mounting member as shown and described in Figure 1). The ignition device 216 is electrically connected to a current source 240, and current can be supplied to the ignition device 216 when heating to the combustion temperature is desired. The detection system may also include a controller 270 that is in signal communication with one or more other components of the detection system.

[0036] Furthermore, the ignition accelerator port 222 is fluidly connected to the ignition accelerator gas source 252 by an ignition accelerator gas valve 257, which can operate to start, stop, increase, or decrease the flow of the ignition accelerator gas. In the embodiment shown in Figure 2, the ignition accelerator port 222 can receive air from an air source 256 and / or ignition accelerator gas from 252 by the operation of the ignition accelerator gas valve 257.

[0037] Alternatively, air from the air source 256 may be used as the ignition accelerating gas. That is, the same air source 256 that supplies air to the burner 206 also supplies air to the ignition accelerating port 222, so the detection system does not need to have a separate ignition accelerating gas source. Or, if the detection system 201 has an ignition accelerating gas source 252, the air source 256 for the burner 206 does not need to be fluidly connected to the ignition accelerating port 222. In such embodiments, the ignition accelerating gas source 252 may be air or another gas. In embodiments where the ignition accelerating gas is not air, the ignition accelerating gas source 252 may include carbon dioxide (CO2), nitrogen (N2), argon (Ar), xenon (Xe), nitrous oxide (N2O), helium (He), hydrogen (H), or chlorofluorocarbons (CFCs). In some embodiments, the detection system includes a makeup gas source, and the makeup gas is also used as the ignition accelerating gas. In this embodiment, the makeup gas source is fluidly connected to the ignition acceleration port.

[0038] The controller 270 may use one or more computing devices (e.g., personal computers) and may comprise one or more types of hardware, firmware, and / or software, as well as one or more memories and databases. The controller 270 is in signal communication with other systems, devices, or components of the detection system 201 (for example, partially represented by dashed lines in Figure 2). More specifically, in Figure 2, the controller 270 is in signal communication with the measuring instrument 242, the ignition accelerator source 252 or ignition accelerator gas valve 257, and the current source 240. The controller 270 is also in signal communication with the air source 256, the fuel source 254, or valves connected to such sources that control the flow from them. In some embodiments, it is possible to add or remove components with which the controller 270 is in communication.

[0039] This detection system may comprise a combustible fuel source 254, an air source 256, an eluted sample from a chromatographic column, a measurement system, and various other components. Each gas source is equipped with a measurement system capable of measuring specific amounts of hydrogen 254, air 256, and / or the eluted sample, respectively, prior to supplying the mixture to the burner 206. The measurement system can also combine the measured hydrogen, air, and / or the eluted sample as a specific mixture prior to delivering the sample to the burner 206. For example, the measurement system can measure hydrogen 254 and combine it with the eluted sample prior to supplying the mixture to the burner 206.

[0040] The controller 270 can be configured to receive data from the measuring instrument 242 and determine the concentrations of ions and test substances in the sample based on this data. The display method for the test substance can be selected by the manufacturer or user of the detection system 201, but it is often displayed as a graph with time on the x-axis and detector response on the y-axis.

[0041] In some embodiments, the flame-based detector or detection system is included in analytical instruments such as chromatographic analyzers. For example, the detection system 201 is fluidly connectable to a gas chromatography column 280. The chromatographic analyzer may further include other chromatographic components such as a sample injector 282 or an oven surrounding the chromatography column.

[0042] Figures 3A and 3B show one embodiment of a flame base detector 302 having an ignition-promoting port 322 that is in fluid communication with an ignition-promoting gas conduit 321. More specifically, the ignition-promoting member 323 is attached to the housing 304 by fasteners 325, although other clamps or mounting means may also be used. The ignition-promoting member 323 has one or more bores for providing a flow path and / or receiving the conduit. As shown in Figure 3B, the ignition-promoting member 323 includes a central bore 327 for receiving the ignition-promoting gas conduit 321. Alternatively, the need for the member 323 can be eliminated by directly attaching the conduit 321 to the 304 by brazing, welding, etc.

[0043] Figure 3B also shows that a sealing material 329 may be placed at the end of member 323 such that a liquid-tight seal is formed at the position where the bore 327 flows the ignition-promoting gas into the ignition-promoting port 322. The detector 302 also includes an ignition device mounting member 318 that is inserted into the housing 304 and connected to the port or current line 319.

[0044] How to ignite a flame-based detector Another aspect of the present invention provides a method for igniting a flame-based detector, which facilitates the ignition of a burner. This method may include supplying fuel and air to the detector so that the fuel and air flow to an ignition device, flowing an ignition-promoting gas toward the ignition device of the detector, and igniting a flame in the flame-based detector. In some embodiments, the ignition-promoting gas of the flame-based detector is flowed and stopped over one or more cycles during the ignition period. For example, a cycle includes flowing the ignition-promoting gas for about 0.05 seconds to about 0.1, 0.3, or 0.5 seconds, and stopping the ignition-promoting gas for about 0.5 seconds to about 1, 3, or 5 seconds. The cycle may be stopped upon ignition of the burner, completion of the current cycle, or interruption of the current cycle. The method may also include supplying air to the detector through an air passage and gradually increasing the flow of air to the detector. In some embodiments, this method includes stopping the flow of ignition-promoting gas after the air-increasing period, immediately after the end of the air-increasing period, or within a few seconds, by closing the ignition-promoting port or the like.

[0045] Definition of Terms It should be understood that the technical terms used herein are for the purpose of describing specific embodiments only and are not intended to be limiting in any way. The definitions of these terms are an addition to the technical and scientific meanings of the definition terms as generally understood and accepted in the art of the subject matter of this teaching.

[0046] The term "connected" means that two components are fluidly connected, physically connected, or both. The term "fluidically connected" means that two components are in fluid communication, and includes not only direct connections between these two components, but also indirect connections where one or more other components are present in the flow path between the two components. For example, a first component and a second component are fluidly connected if, when fluid flows from the first component to the second component or vice versa, the outlet of the first component is physically connected to the inlet of the second component, or a conduit connects the first and second components, or one or more intervening elements such as a valve, pump, or other structure are present between the two components. Components can be physically connected by any preferred method, such as the use of fittings, brazing, and other techniques. Generally, liquid-tight physical connections and / or physical connections that minimize dead volume are desirable for this device.

[0047] Two or more systems, devices, or components are “signal-connected” if they can communicate with each other by signals traveling through some kind of signal path. A signal path can be physical, electrical, magnetic, electromagnetic, electrochemical, optical, wired, or wireless. A signal path can also include additional systems, devices, or components.

[0048] The term "flow path" generally refers to any structure configured to allow fluid flow. A flow path may be a tube or channel formed in a substrate. A flow path may be formed by, or include, one or more tubes or channels that are in fluid communication. While a flow path typically has one inlet and one outlet, in some embodiments it may have multiple inlets and / or outlets. The shape of a flow path may vary widely and include circular, rectangular, square, D-shaped, trapezoidal, or other polygonal cross-sections. A flow path may include various shapes (for example, rectangular in one part and trapezoidal in another). In some embodiments, the cross-sectional area of ​​the flow path is substantially constant.

[0049] The term "port" encompasses any opening or structure that allows fluid to pass through (including inlets, outlets, conduits, openings, or other openings). The term "conduit" generally encompasses any structure, such as tubes, that defines a flow path for fluid to move from one point (e.g., the inlet of a conduit) to another point (e.g., the outlet of a conduit), although conduits can also deliver fluid to intermediate points. Conduits can be flexible, rigid, or both, to some extent or in part. Typically, conduits are relatively long and / or linear, providing a flow path from one component (e.g., a gas source) to another.

[0050] In some embodiments, the detector includes a suitable sealing material. For example, the ignition facilitator may have a suitable sealing material, such as an elastic material that is essentially impermeable to fluids, in the form of an O-ring, in one or more openings. In some embodiments, the mounting member or other component of the detector includes one or more recesses for receiving the suitable sealing material. The suitable sealing material can be any suitable shape, such as a toroidal O-ring, a rectangular cross-section gasket, a metal gasket, or another type of suitable material. In some embodiments where the suitable sealing material is in the form of an O-ring, the O-ring shall be compressed by 15% to 25% or 20% to form a liquid-tight seal. Alternatively, a flat or cylindrical gasket may be used as the suitable sealing material instead of an O-ring, and the desired compression ratio may differ. In some embodiments, the suitable sealing material can be made of various rubbers (e.g., fluoropolymer, Buna-N, EPDM, or, in extreme cases, a metal with a suitable coating (plating)) depending on the temperature and gas used in the detector. The suitable sealing material may also be coated with a chemically inert coating where materially feasible.

[0051] In this disclosure, the terms “substantial” or “substantially” mean within the limits or extent acceptable to a person skilled in the art. The terms “approximately” and “about” mean within the limits or amount acceptable to a person skilled in the art. The term “about” generally represents ±15% of a specified number. For example, “about 10” could mean a range of 8.5 to 11.5. For example, “approximately the same” means that the items being compared are considered to be the same by a person skilled in the art. Where a range of values ​​is described in this disclosure, unless otherwise explicitly specified in the context, it is understood that each midpoint between the upper and lower limits of that range is also specifically disclosed to one-tenth of the lower limit. Any smaller range between any stated value or midpoint within the range and any other stated value or midpoint within the range is also included in this disclosure. These smaller upper and lower limits may be independently included in or excluded from the scope, and each of these smaller limits is also included in the disclosure, in accordance with any specifically excluded limits of the scope described. If the scope described includes one or both limits, the scope excluding one or both of those included limits is also included in the disclosure.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this disclosure pertains. Any methods and materials similar to or equivalent to those described herein may be used in carrying out or testing the teachings herein, but only some exemplary methods and materials are described here. All patents and publications referenced herein are expressly incorporated herein.

[0053] In use herein and in the claims, the terms “a,” “an,” and “the” include both singular and plural referents unless otherwise specified in the context. For example, “a component” includes one component and multiple components. The terms “first” and “second” conduits (or other “first” and “second” elements) are terms used to distinguish different elements, not terms that impose numerical limitations. Furthermore, a device having first and second elements may also include third, fourth, fifth, and so on, unless otherwise specified.

[0054] In consideration of this disclosure, the method can be implemented in accordance with the teachings provided. Furthermore, various components, materials, structures, and parameters are included only as examples and illustrations and are not limiting in any way. In consideration of this disclosure, the teachings can be implemented in other applications, and the components, materials, structures, and equipment for realizing these applications can still be determined within the scope of the claims.

[0055] Exemplary Embodiments Exemplary embodiments provided in accordance with the subject matter of this disclosure include, but are not limited to, the following:

[0056] Embodiment 1. A flame base detector comprising a housing having an upstream region and a downstream region; a burner disposed in the upstream region of the housing; a fuel passage for supplying combustible fuel to the burner; an air passage for supplying air to the burner; a collector which is a collector in the housing and is an ion collector or a photon collector; an ignition device in the downstream region; an ignition acceleration port located near the ignition device and configured to direct an ignition acceleration gas toward the ignition device; and an exhaust port in the downstream region of the housing for discharging exhaust gas from the housing.

[0057] Embodiment 2. The flame-based detector according to Embodiment 1, wherein the ignition device is a filament mounted inside or downstream of the collector tube.

[0058] Embodiment 3. The flame base detector according to Embodiment 2, further comprising an ignition device mounting member connected to a housing, wherein the filament is located inside the ignition device mounting member.

[0059] Embodiment 4. The flame base detector according to Embodiment 1, further comprising an ignition promoting member connected to the housing.

[0060] Embodiment 5. A flame base detector according to any one of Embodiments 1 to 4, wherein the ignition acceleration port is configured to blow a protective gas directly onto the ignition device.

[0061] Embodiment 6. A flame base detector according to any one of Embodiments 1 to 5, wherein the ignition device and ignition acceleration port are located on the sides of the housing facing each other.

[0062] Embodiment 7. A flame base detector according to any one of Embodiments 1 to 4, wherein the ignition acceleration port is located at a distance of approximately 1 mm to approximately 25 mm from the ignition device.

[0063] Embodiment 8. A flame base detector according to any one of Embodiments 1 to 4, wherein the ignition acceleration port is angled and located at a distance of approximately 1 mm to approximately 25 mm upstream or downstream of the ignition device.

[0064] Embodiment 9. A flame-based detector according to any one of Embodiments 1 to 8, wherein the ignition acceleration port is circular or oval.

[0065] Embodiment 10. A flame-based detector according to any one of Embodiments 1 to 9, wherein the ignition acceleration port has a diameter or longest dimension of approximately 0.3 mm to approximately 1.0 mm.

[0066] Embodiment 11. A flame-based detector according to any one of Embodiments 1 to 10, comprising a plurality of ignition-promoting ports uniformly arranged on the inner circumference of the housing.

[0067] Embodiment 12. A flame-based detector according to any one of Embodiments 1 to 11, wherein the burner comprises a nozzle for forming a jet containing fuel and air.

[0068] Embodiment 13. A flame-based detector according to any one of Embodiments 1 to 12, wherein the collector is an ion collector.

[0069] Embodiment 14. A flame-based detector according to any one of Embodiments 1 to 12, wherein the collector is a photon collector.

[0070] Embodiment 15. The flame-based detector according to Embodiment 14, comprising a photomultiplier tube (PMT).

[0071] Embodiment 16. A detection system comprising a flame-based detector as described in any one of Embodiments 1 to 15, a measuring instrument configured to measure a signal from a collector, and a controller in signal communication with one or more other components of the detection system.

[0072] Embodiment 17. The detection system according to Embodiment 16, further comprising a combustible fuel source fluidly connected to a fuel flow path and an air source fluidly connected to a fuel flow path.

[0073] Embodiment 18. The detection system according to Embodiment 16 or 17, wherein an air source is fluidly connected to an ignition acceleration port.

[0074] Embodiment 19. The detection system according to any one of embodiments 16 to 18, further comprising an ignition-promoting gas source fluidly connected to an ignition-promoting port.

[0075] Embodiment 20. The detection system according to any one of embodiments 16 to 19, further comprising an ignition-promoting gas valve that is in signal communication with a controller and is fluidly connected to an air source and / or an ignition-promoting gas source.

[0076] Embodiment 21. A method for igniting a flame-based detector according to any one of Embodiments 1 to 15, comprising: supplying fuel and air to the detector so that the fuel and air flow to an ignition device; flowing an ignition-promoting gas toward the ignition device of the detector; and igniting a flame in the flame-based detector.

[0077] Embodiment 22. The method according to Embodiment 21, further comprising intermittently flowing an ignition-promoting gas during the ignition period.

[0078] Embodiment 23. The method according to Embodiment 22, wherein the ignition-promoting gas is flowed and stopped over one or more cycles during the ignition period, the cycle comprising flowing the ignition-promoting gas for about 0.05 seconds to about 0.3 seconds and stopping the ignition-promoting gas for about 0.5 seconds to about 3 seconds.

[0079] Embodiment 24. The method according to any one of Embodiments 21 to 23, comprising increasing the airflow to the detector over the entire air increase period and essentially stopping the flow of the ignition-promoting gas immediately after the end of the air increase period.

[0080] Embodiment 25. The method according to any one of Embodiments 21 to 24, wherein an ignition-promoting gas is flowed into the ignition-promoting port at a flow rate of approximately 18 ml / min to approximately 90 ml / min.

[0081] Embodiment 26. The method according to any one of Embodiments 21 to 25, wherein the ignition promoting gas is selected from the group consisting of carbon dioxide (CO2), nitrogen (N2), argon (Ar), xenon (Xe), nitrous oxide (N2O), helium (He), hydrogen (H), chlorofluorocarbons (CFCs), and mixtures thereof.

[0082] The above description relating to exemplary or preferred embodiments should be considered as examples only and not as limiting the invention as defined by the embodiments. Naturally, many variations and combinations of the above features are available without departing from the invention as shown in the embodiments. Such variations are not considered departures from the scope of the invention and are all included within the scope of the incidental embodiments. All of the contents of all references cited herein are incorporated herein by reference.

Claims

1. Flame-based detector, A housing having an upstream area and a downstream area, A burner disposed within the upstream region of the housing, A fuel passage for supplying combustible fuel to the burner, An air passage for supplying air to the burner, A collector within the housing, which is an ion collector or a photon collector, An ignition device provided in the downstream region, An ignition accelerator port located near the ignition device and configured to direct the ignition accelerator gas toward the ignition device, A flame-based detector comprising an outlet for discharging exhaust gas from the housing in the downstream region of the housing.

2. The flame base detector according to claim 1, wherein the ignition device is a filament installed inside or downstream of the collector tube.

3. The flame base detector according to claim 2, further comprising an ignition device mounting member connected to the housing, wherein the filament is located inside the ignition device mounting member.

4. The flame base detector according to claim 1, further comprising an ignition promoting member connected to the housing.

5. The flame base detector according to claim 1, wherein the ignition acceleration port is configured to blow the ignition acceleration gas directly onto the ignition device.

6. The flame base detector according to claim 1, wherein the ignition device and the ignition acceleration port are arranged on opposite sides of the housing.

7. The flame base detector according to claim 1, wherein the ignition acceleration port is located upstream or downstream of the ignition device at a distance of approximately 1 mm to approximately 25 mm.

8. The flame base detector according to claim 1, wherein the ignition acceleration port is angled with respect to the orientation of the ignition device and is located upstream or downstream of the ignition device at a distance of about 1 mm to about 25 mm.

9. The flame base detector according to claim 1, wherein the ignition acceleration port has a diameter or longest dimension of approximately 0.3 mm to approximately 1.0 mm.

10. The flame base detector according to claim 1, further comprising a plurality of ignition-promoting ports arranged on the inner circumference of the housing.

11. The flame-based detector according to claim 1, wherein the burner comprises a nozzle for forming a jet containing fuel and air.

12. The flame-based detector according to claim 1, wherein the collector is an ion collector.

13. The flame-based detector according to claim 1, wherein the collector is a photon collector.

14. A flame-based detector according to claim 13, comprising a photomultiplier tube (PMT).

15. A detection system comprising: a flame-based detector according to claim 1; a measuring instrument configured to measure a signal from the collector; and a controller in signal communication with one or more other components of the detection system.

16. The detection system according to claim 15, further comprising a combustible fuel source fluidly connected to the fuel flow path and an air source fluidly connected to the fuel flow path.

17. The detection system according to claim 15, wherein the air source is fluidly connected to the ignition acceleration port.

18. The detection system according to claim 15, further comprising an ignition-promoting gas source fluidly connected to the ignition-promoting port.

19. The detection system according to claim 15, further comprising an ignition-promoting gas valve that communicates with the controller via signals and is fluidly connected to the air source and / or the ignition-promoting gas source.

20. A method for igniting a flame base detector according to claim 1, Fuel and air are supplied to the detector so that the fuel and air flow to the ignition device, The ignition-promoting gas is flowed toward the ignition device of the detector, The flame is ignited in the flame base detector, Methods that include...

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