TWI817017B - Burner for generating a flame for the combustion of process gas and exhaust gas treatment device with a burner - Google Patents

Abstract

The invention relates to a burner as well as to a waste gas treatment device for the generating a flame for the combustion of process gas, especially of contaminants, in a combustion chamber, in each case having feed lines for a fuel gas and for an oxidizing agent so that they flow into a pre-mixing chamber, and having an ignition device for igniting the gas mixture contained in the pre-mixing chamber. According to the invention, a sensor for detecting and/or monitoring the flame is provided on the burner, especially at one end of the burner situated opposite from the pre-mixing chamber.

Description

Burners for generating flames for process gas combustion and exhaust gas treatment devices with burners

The present invention relates to a burner for generating a flame for programmed gas combustion and an exhaust gas treatment device having a burner.

Many factories used to process semiconductor materials or to produce photovoltaic cells use gases for film deposition and etching. Reactive and environmentally hazardous process gases and their reaction products generated during the process are usually disposed of in local waste disposal facilities near the treatment plant. These toxic gases are also formed in large quantities, for example, during the production of semiconductor circuits, and due to their toxicity, they cannot be released into the environment without first being treated.

In addition to process gases from such chemical vapor deposition (CVD) or dry etching processes, the present invention can also treat waste gases from other processes that contain pollutants. Such toxic or environmentally harmful gas systems are, for example, SiH ₄ , SiH ₂ Cl ₂ , SiF ₄ , NH ₃ , PH ₃ , BCl ₃ , SF ₆ or NF ₃ .

As the demand for these modified substrates increases, increasing amounts of process gases must be handled to ensure compliance with environmental and health and safety requirements.

For this purpose, a common method consists of combustion treatment followed by washing with a washing liquid. A known procedure is to place a burner in the cover of a combustion reactor and to supply harmful gases through tubes leading to the vicinity of the flame.

The reaction products of heat treatment exist in gas form or solid form. After washing away the water-soluble gases and solid particles, the remaining gaseous reaction products (such as water vapor or _CO2 ) can be released into the environment without any further subsequent processing.

It goes without saying that many combustion methods and reaction chambers have been developed and used in actual practice for thermal reactions. For example, European patent specification EP 0 346 893 B1 discloses an arrangement for cleaning exhaust gases, which consists of a reaction chamber in which a burner is arranged at the bottom, which on the one hand utilizes fuel gases such as hydrogen and oxygen or air or other natural gas and air) operation, and on the other hand receives the exhaust gas to be cleaned. The reaction products produced during combustion contain solid components and water-soluble reaction products.

Korean patent specification KR 1 275 475 B and Chinese examination application 102 644 928 B disclose a heat treatment device for exhaust gas containing harmful substances. Convert these substances into other compounds. The heat treatment device has a combustion chamber, one or more burners, one or more exhaust gas inlets and an exhaust gas outlet.

German patent application DE 10 342 692 A1 discloses a device with a combustion chamber with at least one burner arranged on a cover at the top, so that a flame is directed from top to bottom into the interior of the combustion chamber. There is also a supply line for a washing liquid, whereby a continuous film can be formed over the entire inner circumferential surface of the combustion chamber.

German patent application DE 10 2004 047440 A1 discloses a reactor chamber, which has: an outer wall and an inner wall, wherein the inner wall tapers downward at a specified angle in the form of a funnel; and a device for heat treatment Toxic gas, the device is configured on the reactor chamber to Seal the reactor chamber near the bottom. Inside the inner wall of the reactor chamber, there is a water film flowing downwards evenly.

Japanese published unexamined patent application JP 2017 089985 A discloses an exhaust gas treatment device for heat treatment of exhaust gas, which has a combustion chamber for burning exhaust gas. The ignition device has an air-fuel premixing chamber and a spark plug for generating an ignition flame.

U.S. Patent Application No. 2017 065 934 A1 and U.S. Patent Specification No. 9956525 B2 disclose an equipment for purifying waste gas of an integrated semiconductor, which has a cover with a burner mounted thereon to generate a flame and has a plurality of exhaust gas inlet pipe. A water curtain prevents by-products from accumulating in the equipment.

For safety reasons, combustion reactors are usually equipped with a flame detector. The flame detector is used to monitor the status of the burner so that if the flame goes out, the supply of fuel gas and toxic gas to the reactor is interrupted. Then, the automatic switching three-way valve can transport the toxic gas through the reactor to another reactor or a line used to discharge harmful waste gas. One device of this general type is disclosed in German patent document DE 10 2015 106 718.

Japanese published unexamined patent application JP 2017 089986 A discloses a combustion reactor with a liquid film on the wall, in which a flame detector detects flames directly passing through the liquid film.

US Patent Application No. 2014 0106282 A1 discloses a device with two flame sensors that are guided from the side of a burner through an opening in the wall into a reaction chamber.

One disadvantage of prior art devices is the fact that ionization current monitoring is unstable and error-prone. Especially when oxygen is used as the oxidant, the ionization range is narrowly limited and will shift when the quality of the gas changes, which will lead to an unreliable measurement of the ionization current. In addition, it is necessary to avoid Avoid contact between the electrode and harmful gas combustion products, in other words, particles or acids, which reduce the conductivity of the electrode.

This is the reason why optical detection is proposed. For this purpose, holes should be added to the reaction chamber, but this is difficult to integrate into the existing design. Since there is generally little space available in the lid of the reactor, it is usually no longer possible to drill additional holes in it. In addition, high temperatures in the covered area are harmful to the detector and the accuracy of the measurement results. Since the liquid flows along the inner wall, it becomes more difficult to penetrate a hole through the side wall of the reactor.

Against the background of the above-mentioned disadvantages, the present invention is based on the purpose of thermally treating process gases containing contaminants, in which a reliable and accurate flame detection will be achieved.

This object is achieved by a burner according to claim 1 for generating a flame for process gas combustion.

This object is also achieved by an exhaust gas treatment device with a burner as claimed in claim 18.

The invention relates to a burner for generating a flame in a combustion chamber for the combustion of process gases, in particular pollutants. There is a supply line for a fuel gas and a supply line for the oxidant to flow the combustion gas and the oxidant into a premixing chamber, and there is also an ignition for igniting the gas mixture contained in the premixing chamber. device.

According to the invention, a sensor for detecting and/or monitoring the flame is arranged on the burner, in particular at one end of the burner positioned opposite the premixing chamber.

The arrangement of the sensor or detector as a flame monitor in the burner results in a very compact embodiment. Furthermore, the sensor is only in contact with clean burner gases and the space in front of the sensor is continuously flushed. In prior art arrangements, an additional opening to the combustion chamber was required, and an additional flush flow was always required to protect the sensor. In the present invention, the sensor or detector can be divided into Analyze the entire flame in each state. In contrast to previous technologies, a pilot is not required for ignition purposes since the ignition device is integrated into the burner and a combustible mixture is produced in the premixing chamber.

Due to the formation of particles during the combustion process, it is necessary to flush all connections on an exhaust gas treatment device with a burner (a so-called reactor) to prevent the formation of deposits. For this reason, the number of holes formed in the exhaust gas treatment device or reactor should be kept to a minimum.

In contrast to prior art, the present invention requires neither an ignition burner nor a hole for a flame sensor. In addition, the burner is particularly compact. Therefore, supply lines for toxic gases can be placed very close to the flame.

According to a first advantageous embodiment of the invention, the fuel gas and the oxidant can each be fed into the premixing chamber of the burner in a substantially cylindrical tube, wherein the cylindrical tubes are configured concentrically with respect to each other tube and an inner tube, wherein the outer tube and the inner tube are arranged at a radial distance from each other. This makes the burner easy to assemble and disassemble and, among other things, production costs are reduced and the structure becomes overall more compact.

As explained in the present invention, in addition to cylindrical tubes, tubes with other geometric shapes are also conceivable, such as, for example, polygonal, and especially hexagonal, shapes.

Another advantageous variant of the invention provides that the sensor is an optical sensor, in particular an ultraviolet (UV) or infrared (IR) sensor, wherein the flame falls within the optical field of view of the sensor. Sensors are easy to install and less prone to failure than electrical measurement methods.

Due to optical detection, flames using different types of fuel gases can be detected. In particular, the combustion of hydrogen can also be detected optically.

Different detectors with different spectral ranges are commercially available for a variety of applications, allowing for an overall broad range of applications.

Optical detection allows the burner to be operated with a supply of fuel gas through the outer tube and a supply of oxygen through the inner tube or otherwise with a supply of fuel gas through the inner tube and a supply of oxygen through the outer tube. It is also conceivable to use an IR detector to detect the burning of a thin line in the flame inside the premixing chamber. An IR detector is advantageous if the burner has been mounted in the reactor in such a way that the view of the detector through the supply line is oriented towards, for example, a cold surface flushed by the liquid.

Likewise, it is also fundamentally conceivable to use an electrical detection modality, ie ionization current monitoring.

According to an advantageous embodiment of the invention, the visual axis of the optical sensor approximately coincides with the longitudinal axis of the burner, in particular the sensor detects and monitors the flame passing through the inner tube of the burner. In this way, a large detection area is covered thereby allowing a reliable and comprehensive detection and continuous monitoring of the flame. In prior art burners, the detector had only a limited field of view in the longitudinal direction of the flame.

In a further development of the invention, a glass plate, in particular a quartz glass plate, is arranged between the burner and the sensor, so that the structure is also simplified and therefore more cost-effective. In addition, the quartz glass plate separates the sensor from the fuel gas and also seals the gas supply line. Therefore, the sensor is not in contact with the fuel gas and does not have to be self-sealing.

It is particularly advantageous to carry the fuel gas in the outer or inner tube and the oxidant in the outer or inner tube. Since complete mixing in the premix chamber is not required, the choice of gas type externally can influence to some extent which chemical compositions that come into contact with toxic gases are predominant in the combustion chamber, for example a low-oxygen or a high-oxygen composition. This affects combustion efficiency and the formation of nitrogen oxides.

In a further development of the invention, the inner tube and the outer tube are electrically conductive and are electrically insulated from each other by an insulator. A voltage for an ignition spark can be applied between the tubes so that the mixture can be ignited gas.

According to an advantageous embodiment of the invention, preferably the optical sensor is electrically insulated from the inner tube. When a high voltage is applied to create an ignition spark, the photosensitive sensor does not become charged, thus protecting it from overvoltage damage. This also prevents falsification of measurement values that can be caused by overvoltage.

Another advantageous embodiment of the invention provides that the ignition device has at least one protrusion arranged on the lower end of the inner tube and in particular oriented towards the outside and/or the ignition device has at least one projection arranged on the outer tube and in particular oriented towards the inside. At least one protrusion of an ignition spark is generated between the tube and the outer tube. The burner can be ignited directly by an ignition spark. Ignition requires a relatively low high voltage compared to previous technologies. Ignition works reliably.

According to an improvement of the present invention, the ignition device has an electrode arranged in the premixing chamber and used to generate an ignition spark in the premixing chamber. In this variant, the ignition voltage is applied not via a tube carrying the gas but via an electrode inserted in a manner convenient for insulation and leading into the premixing chamber, and the ignition spark is generated against the grounded outer tube. In the present invention it is advantageous that all burner parts can be grounded and only one insulated supply line has to be implemented in the mixing chamber.

In another variant of the invention, the outer tube is electrically grounded and the inner tube is connected to an ignition adapter or ignition transformer via a connector for high voltage to generate an ignition spark from the inner tube to the outer tube. One of the tubes is connected to ground, while the other (preferably, the inner tube) is connected to a voltage source. In this way, an ignition spark can be generated systematically at the end of the inner tube in the area of transition to the mixing chamber. Electrical insulation can be achieved more easily if it is located in the cold part of the burner. For electrical safety, the outer tube should be grounded and the inner tube should carry the ignition voltage. Otherwise, the risk of ignition voltage being discharged to the outside will be greater.

The inner tube can be configured as an electrode for measuring the ionization current in the premix chamber. When the inner tube is installed to be electrically insulated, not only can the ignition voltage be carried through it, but it can also be carried by an The applied AC voltage produces a flame signal in the form of a rectified current component, as long as there is no ignition. In addition, electrical detection can be used as a redundant signal to improve burner safety.

According to another advantageous embodiment of the invention, the outer tube is made of electrically insulating ceramic, at least in the area of the premixing chamber. The premixing chamber may be formed by the lower end of the outer tube. It is also conceivable that the entire tube is made of insulating ceramic.

In a further development of the invention, a high-temperature resistant wire (a so-called glow wire) is arranged in the premixing chamber and projects into the optical field of view of the sensor. In the premixing chamber, a flame has been formed in the area where the fuel gas and the oxidant are mixed, and this causes the wire to heat up. The wire continues to be heated by the resulting flame until the wire begins to glow, which can then be seen, for example, by an IR detector. If the wire is very thin, it cools quickly after the flame is extinguished, so it can be used as a way to detect the flame. This prevents a so-called afterglow, which would produce an undesirable false positive signal.

According to another advantageous embodiment of the invention, there is provided a flame stabilizer arranged in the premixing chamber to generate turbulence. When air is used instead of oxygen as the oxidant, a flame stabilizer is required. Since then, without a flame stabilizer, the flame speed is so low that the flame will blow out of the premixing chamber. The turbulence generated at the flame stabilizer stabilizes the flame at the flame stabilizer. A flame holder can be electrically connected to the outer tube and can be used to generate an ignition spark.

For mechanical stabilization or centering, at least one spacer can be provided between the inner and outer tubes. Typically, the spacers are configured to be electrically insulating because otherwise a spark would not be generated.

According to a refinement of the invention, a tubular connection is provided between the outer tube and the sensor and has a supply line for carrying fuel gas or oxidant to the inner tube. In this way, the burner can be easily assembled and disassembled, and its size and length can be varied by using different connectors. In addition, the connector is used to establish an electrically insulating connection between the gas supply line and the sensor. It can itself be electrically grounded.

In another embodiment of the invention there is provided a glass plate with a sensor arranged at one end of a substantially cylindrical connector and an inner and/or outer tube arranged at the other end electrically insulated by an insulator . This makes the structure of the burner simpler and more compact.

The structure of the burner can be further improved if a connector for ignition means, especially for high voltages, is provided between the connecting piece and the outer tube.

According to an independent aspect of the invention, there is provided an exhaust gas treatment device or a so-called reactor having at least one burner arranged in a combustion chamber to generate a flame for combustion of process gases, preferably toxic gases.

The device has at least one process gas supply component and at least one heat treatment exhaust gas discharge component.

The integration of the flame detector into the burner allows the exhaust gas treatment device to have a compact shape, and the process gas supply components can be placed very close to the flame in the reactor. This allows the flame to interact more intensely with the process gas.

Since particles are formed during the combustion process, all connections on the exhaust gas treatment device or reactor must be flushed to prevent deposits. For this reason, the number of holes in the reactor should be kept to a minimum.

The present invention requires neither an ignition burner nor a hole for a flame sensor. In addition, the burner is very compact, so the supply line for toxic gases can be placed very close to the flame.

Specifically, the burner and toxic gas supply components can also be integrated into one module. Here, for example, the burner can be positioned centrally and the toxic gas inlets can be positioned around the burner in a compact module. This translates into a reduction in the number of threaded connections required on the reactor lid and allows the toxic gas supply components to be placed in close proximity to the burner or flame.

According to a first advantageous development of the exhaust gas treatment device according to the invention, when the burner is in its assembled position, it is positioned above the combustion chamber, in particular approximately perpendicularly to the exhaust gas treatment device. This ensures that the flame interacts evenly with the toxic gases within the combustion chamber.

The design including a vertically mounted burner simplifies the use of optical detectors with moving parts, such as for example a cover or a so-called shutter for self-monitoring.

According to an advantageous embodiment of the invention, a supply line is provided for a purge gas, in particular nitrogen, wherein the purge gas can flow through a porous sintered element at the end of the process gas supply member to remove particles. In some processes, especially toxic gas outlets into the reactor, deposits accumulate due to resurgence of moisture, oxidants or even due to thermal reactions. However, it may also be advantageous to supply heated flush gas, especially in the case of process gases that tend to condense on cold surfaces.

According to another advantageous embodiment of the invention, a liquid supply line is provided, in particular on a side wall of the combustion chamber. The burner according to the invention may be deployed in an exhaust gas treatment device or in a reactor on whose walls liquid flows. To protect the toxic gas inlet from splashing liquid, a small collar can be installed on the side wall in front of the liquid supply line. For better thermal insulation, the lid of the reactor can be configured with a double wall. An elevated surface temperature on the inside of the cover reduces the likelihood that solid deposits will accumulate. A purge gas (such as, for example, nitrogen) can be supplied through the double wall cover and flowed through the porous sintered element at the end of the toxic gas supply line to dislodge particles.

According to a refinement of the method, a plunger is provided for cleaning deposits on the process gas supply component. However, if deposits accumulate on the walls in a toxic gas inlet, they can be automatically scraped off by the plunger. As another alternative, a nozzle could be installed in the toxic gas inlet and at certain points in time or when the pressure in the toxic gas line increases, it generates a pulse of gas to blow away deposits on the wall. It can also be sprayed from a nozzle installed in the toxic gas inlet. One liquid cleaner. To prevent deposits on the reactor lid, a purge gas can flow from the edge of the lid to the center of the lid.

Due to the compact design of the burners, embodiments with several burners on one exhaust gas treatment device or one reactor are also possible. For this purpose, for example, the poisonous gas supply member is arranged in the middle of the reactor lid, and two or more burners are arranged along an outer circle around these supply members, preferably with the flame slightly inclined towards the middle. The burner can also be tilted in such a way that it creates a vortex in the reactor, thus allowing a more stable flow and better mixing in the reactor.

In the burner according to the invention, ignition and flame detection are integrated so that other designs can be envisaged, in which one or more burners extend into the combustion chamber through the side walls over which the liquid flows, these burners facing from above The toxic air flow supplied through the cover exerts its effect.

To achieve a particularly elongated configuration of the exhaust gas treatment device, the burner can be arranged in the middle of the lid of the reactor and the toxic gas supply means can pass through the side walls of the reactor.

According to another advantageous embodiment of the invention, at least one supply line for a reaction gas, in particular an oxidant and/or a reducing agent, is provided. Even though the combustor allows for varying fuel gas-oxidant ratios, some procedures may require additional oxidant (such as air or oxygen) or reducing agent (such as fuel gas) to be fed into the reactor. These reaction gas supply lines can be installed in the lid of the reactor.

According to another advantageous embodiment of the invention, the exhaust gas treatment device has at least two burners arranged on the combustion chamber, wherein each burner is associated with a separate fuel gas or oxidant supply means. This embodiment provides redundancy during operation of the burner to thereby avoid high downtime costs for the process plant when a burner fails and a burner must be repaired.

An improvement of the present invention provides an adjustment and/or control unit to adjust and/or Or control the fuel gas or oxidant supply means, in particular as a function of a signal from a sensor arranged on the relevant burner and used to detect and/or monitor the flame of the relevant burner.

It may be provided that the sensor is a flame ionization electrode. In this embodiment of the exhaust gas treatment device, the electrodes can be inserted into the flame through the burner, in particular through the inner tube, to prevent the electrodes from becoming dirty. When flame monitoring of several burners is involved, electrical flame monitoring can be more advantageous than optical flame monitoring because it systematically monitors the flame of the associated burners. Optical flame monitoring systems sometimes detect the flames of several burners, making it impossible to determine the status of an individual burner at all or accurately.

Additional objects, advantages, features and application possibilities of the invention will become apparent from the following description of an embodiment of the invention with reference to the accompanying drawing. In the present invention, all described and/or depicted features, by themselves or in any meaningful combination, form the subject matter of the present invention, regardless of their compilation in the claimed patent claims or in the claimed patent claims to which they are referred back.

1: burner

2:Outer tube

3:Inner tube

4: Sensor

5: Supply line to inner tube

6: Supply line to outer pipe

7: Insulator

8:Glass plate/quartz glass plate

9: spacer

10:Protrusion/ignition device/fork tip

11: High voltage connector/ignition device

12: Pre-mixing chamber

13: Flame stabilizer

14:Glow wire/high temperature resistant wire

15:Module

16: Program gas supply component/toxic gas inlet/toxic gas supply component

18: Sintered components

19: Flushing gas supply line

20:Nozzle

21: Cleaning medium supply component

22: Exhaust gas treatment device/reactor

23: Liquid supply member/liquid supply line

24: Collar

25: Reducing gas supply line

26: Wet scrubber

27:Bypass valve

28:Heat exchanger

29:Pump

30:Quenching area

31: Heat treatment exhaust gas emission components

32: Combustion chamber

33: Flame

34: Tubular connector

35:Protrusion of outer tube

36:Electrode

37: Supply components

38: Supply components

39: Regulation and/or control unit

40: Ionization electrode

41: Flush gas connector

42:Bypass

In the present invention, sometimes it is shown schematically as follows: Figure 1 shows a burner with an ignition device and a sensor; Figures 2, 3, 4, 5, 6, 7, 8, 9 and 10 show various implementations. For example, the burner shown in Figure 1; Figure 11 shows a module of an exhaust gas treatment device with a burner shown in Figures 1 to 10; Figure 12 shows a plunger, a sintered element and A module of an exhaust gas treatment device with a purge gas supply line; Figure 13 shows a module of an exhaust gas treatment device including a cleaning medium supply line with a nozzle; Figure 14 shows a module with a quenching zone and a heat treatment exhaust gas discharge member Exhaust gas department treatment device; Figures 15 and 16 show additional embodiments of the exhaust gas treatment device; Figure 17 shows an exhaust gas treatment device with a subsequent washing station and a liquid circulation system; Figure 18 shows an exhaust gas treatment device with two burners and separate supply components Another embodiment of the treatment device; Figure 19 shows another drawing of the exhaust gas treatment device shown in Figure 18; and Figure 20 shows a burner with flame monitoring configured in the form of an ionization electrode.

For the sake of clarity, with reference to an embodiment, the same components or components with the same effects in the following figures have the same reference numerals.

Figure 1 shows a burner 1 for generating a flame 33 for combustion of process gases, in particular pollutants, in a combustion chamber.

Supply lines 5, 6 are used to allow a fuel gas and oxidant to flow into a premixing chamber 12.

An ignition device 10, 11 is provided for igniting the gas mixture present in the premix chamber 12.

Figure 1 also shows a sensor 4 arranged on the burner 1, in particular at one end of the burner 1 positioned opposite the premixing chamber 12, for detecting and/or monitoring the flame 33.

As shown in Figures 1 and 2 to 10, fuel gas and oxidant are each supplied to the premixing chamber 12 of the burner 1 via a substantially cylindrical tube 2, 3. The cylindrical tubes 2, 3 are configured as an outer tube 2 and an inner tube 3 concentric with respect to each other, wherein the outer tube 2 and the inner tube 3 are at a diameter from each other. Distance configuration. Depending on the purpose of the application, the fuel gas can be conveyed in the outer tube 2 or the inner tube 3 and the oxidant can be conveyed in the outer tube 2 or the inner tube 3 correspondingly.

In this embodiment, the inner tube 3 and the outer tube 2 are electrically conductive and are electrically insulated from each other by an insulator 7 .

In the embodiment shown in Figures 8, 9 and 10 and Figures 1 to 6, the outer tube 2 is electrically grounded and the inner tube 3 is connected to an ignition adapter or ignition transformer via a high voltage connector 11 to generate power from the inner tube. One of tube 3 to outer tube 2 ignites the spark. In this way, an ignition spark can be generated systematically at the end of the inner tube 3 in the area of the transition to the premixing chamber 12 . For electrical safety, the outer tube 2 should be grounded and the inner tube 3 should carry the ignition voltage.

An inner tube 3 configured as an electrode to measure an ionization current in the premix chamber 12 may be provided. When the inner tube 3 is installed to be electrically insulated, not only can the ignition voltage be carried through it, but a flame signal can also be generated in the form of a rectified current component by an external AC voltage, as long as there is no ignition. Furthermore, electrical detection can be used as a redundant signal to improve the safety of the burner 1 .

As shown in Figures 1 to 10, in order to mechanically stabilize or center the tubes 2, 3, at least one spacer 9 can be provided between the inner tube 3 and the outer tube 2. The spacers 9 are configured to be electrically insulating, since otherwise a spark would not be generated between the tubes 2, 3.

The embodiment shown in FIGS. 1 to 10 shows that a tubular connection (or a substantially cylindrical connection) 34 is provided between the outer tube 2 and the sensor 4 and has a connection to the inner tube 3 . Fuel gas or oxidant supply line 5. A glass plate 8 , in particular a quartz glass plate, and the sensor 4 are arranged at one end of the tubular connector 34 , while the inner tube 3 and/or the outer tube 2 electrically insulated by an insulator 7 are arranged at the other end. The tubular connector 34 is mainly used to establish an electrically insulating connection between the gas supply line and the sensor. It can be electrically grounded.

In this embodiment, the sensor 4 is configured as an optical sensor, in particular A UV or IR sensor, where the flame 33 falls within the field of view of the sensor 4. The optical sensor 4 is electrically insulated from the inner tube 3 .

As can also be seen in Figures 1 to 10, the visual axis of the sensor 4 substantially coincides with the longitudinal axis of the burner 1, so that the sensor element is aimed through the inner tube 3. Therefore, the sensor 4 directly detects and monitors the flame 33 through the inner tube 3 of the burner 1 .

The embodiment shown in FIG. 10 shows that a high-temperature resistant wire 14 , in particular a glow wire, is arranged in the premixing chamber 12 and protrudes into the optical field of view of the sensor 4 .

As shown in FIGS. 1 to 6 and 8 to 10 , a connector 11 , in particular for applying high voltages, is provided between the tubular connector 34 and the outer tube 2 .

The ignition devices 10 , 11 have at least one projection 10 arranged on the lower end of the inner tube 3 and oriented in particular toward the outside.

As shown in FIGS. 5 , 6 and 9 , it is also possible to provide an ignition device 10 , 11 with at least one protrusion 35 arranged on the outer tube 2 and oriented in particular towards the inside for the purpose of separating the inner tube 3 from the outer tube 2 A spark of fire occurs between them.

This protrusion 35 may be configured, for example, to be interdigitated or pointed (as shown in Figure 5) or otherwise rod-shaped (as shown in Figure 6). As set forth in this disclosure, other geometries are of course also contemplated. For example, Figure 9 shows an upwardly oriented protrusion 35.

As shown in FIG. 7 , the ignition device 10 , 11 has an electrode 36 arranged in the premixing chamber 12 and used to generate an ignition spark in the premixing chamber 12 . In this embodiment, the ignition voltage is applied not via one of the gas-carrying tubes 2 , 3 but via an electrode 36 inserted in a manner convenient for insulation and leading into the premixing chamber 12 and against the grounded outer tube 2 Produce ignition sparks.

It is possible to provide an outer tube 2 made of electrically insulating ceramic at least in the area of the premixing chamber 12 .

The embodiment shown in Figures 8 and 9 illustrates that a flame stabilizer 13 can be provided in the premixing chamber 12 to create turbulence.

In contrast to the embodiment shown in Figure 1 in which the protrusion 10 is formed on the inner tube 3 as a central protrusion, Figure 2 shows an embodiment in which the protrusion 10 is formed by prongs or tines directed towards the outside. As shown in Figure 3, the prongs 10 can run at an inclination. The configuration of the protrusions allows the gas to flow into the premixing chamber 12 and thus also allows the shape of the flame 33 to be influenced.

Figures 11 to 17 show an exhaust gas treatment device 22 or a so-called reactor with at least one burner 1 arranged in a combustion chamber 32 to generate a flame 33 for combustion of process gases, preferably toxic gases. . In particular, this may be one of the burners 1 described above.

The exhaust gas treatment device 22 has at least one process gas supply component 16 and at least one heat treatment gas discharge component 31 .

In the present invention, the burner 1 and the toxic gas supply member 16 are integrated into a module 15 . Here, for example, in this compact module 15, the burner 1 may be positioned centrally and the process gas supply member 16 may be positioned around the burner 1. This translates into a reduction in the number of threaded connections required on the cover of the exhaust gas treatment device 22 and the process gas supply member 16 can be very close to the burner 1 or flame 33 .

Designs involving a vertically mounted burner simplify the use of optical detectors with moving parts, such as for example a cover or a so-called shutter for self-monitoring.

FIGS. 11 to 13 particularly illustrate a module 15 that is part of the exhaust gas treatment device 22 shown in detail in FIG. 17 .

As shown in FIGS. 11 to 13 and 16 and 17 , when the burner 1 is in its assembled position, it is positioned above the combustion chamber 32 , in particular substantially perpendicular to the exhaust gas treatment device. twenty two.

In the present embodiment shown in Figure 12, at least one supply line 19 is provided for a purge gas, in particular nitrogen. Purge gas may flow through the porous sinter element 18 at the end of the process gas supply member 16 to dislodge particles. Especially at the outlet to the exhaust gas treatment device, deposits accumulate due to return moisture, oxidants or even due to heat, and these deposits can be flushed away by the flushing gas.

Typical applications utilize gases that when heated or reacted with oxygen or moisture form solids that can be deposited on all surfaces. Mechanical cleaning tools, such as, for example, scrapers, can be used to remove such deposits from the interior surfaces of the reactor. However, these tools are prone to failure. For this purpose, the burner 1 according to the invention is preferably used in a reactor or an exhaust gas treatment device 22 having a wall over which the liquid flows.

As shown in FIGS. 14 to 17 , liquid supply means 23 are provided in particular on the side walls of the combustion chamber 32 for the exhaust gas treatment device 22 or a reactor over which the liquid flows. To protect the process gas supply member 16 or toxic gas inlet from splashing liquid, a small collar 24 can be installed on the side wall in front of the liquid supply line 23, as can be seen in Figures 14 to 16.

For better thermal insulation, the cover of the exhaust treatment device 22 can be configured with a double wall. An elevated surface temperature on the inside of the cover reduces the likelihood that solid deposits will accumulate. A purge gas (such as, for example, nitrogen) can be supplied through the double wall cover and flowed through the porous sintered element at the end of the toxic gas supply line to dislodge particles.

According to the embodiment shown in Figure 13, a nozzle 20 is provided that is installed in the toxic gas inlet 16 and at certain points in time or when the pressure in the toxic gas line 16 increases, it generates a pulse of gas to blow away Sediments on the wall. It is also possible to use a liquid cleaning sprayed from a nozzle 20 in the toxic gas inlet 16 installed on a cleaning medium supply member 21. To prevent waste Due to the deposition on the cover of the gas treatment device 22, a flushing gas can always flow from the edge of the cover to the middle of the cover.

Even though the combustor 1 allows for varying fuel gas-oxidant ratios, certain procedures may require additional oxidant (such as air or oxygen) or reductant (such as fuel gas) to be supplied into the combustion chamber 32 . The reaction gas supply line 25 can be installed in the cover of the reactor 22 .

As shown in Figure 15, there is a supply line 25 of at least one reaction gas, in particular an oxidant and/or a reducing agent.

As can be seen in Figure 14, the heat treatment exhaust gas discharge member 31 of the exhaust gas treatment device 22 passes into a quenching zone 30 to quickly cool the gas after combustion.

Figure 17 shows a scrubbing station downstream of the exhaust gas treatment device 22 with a wet scrubber 26, a heat exchanger 28 and a pump 29. In this cleaning station, soluble gases and particles such as, for example, solids and acids formed during combustion are washed away by a scrubbing liquid. The washing liquid is delivered to the washing section by the pump 29 and delivered to the exhaust gas treatment device via the heat exchanger 28 and components for regulating and measuring the flow rate (not shown here). Then, the washing liquid returns to a storage tank. . The storage tank has supply lines for fresh water and alkaline solution for pH adjustment and a drain pipe for emptying purposes and sensors for fill level, pH and temperature. The washing station can be connected to the exhaust unit so that a negative pressure can be generated in the exhaust gas treatment device 22 .

Due to the compact design of the burner, several burners 1 can also be configured on an exhaust gas treatment device 22 or a reactor. For this purpose, for example, a poisonous gas supply member 16 is arranged in the middle of the reactor lid, and two or more burners 1 are arranged along an outer circle around these supply members, preferably with the flame 33 towards the middle Slightly tilted. The burner 1 can also be tilted in such a way that it creates a vortex in the reactor 22 thereby allowing a more stable flow and better mixing in the reactor 22 . Figures 14 and 15 show an embodiment with two burners 1. In Figure 18 to The embodiment shown in Figure 20 also provides several, especially two, burners 1.

Since ignition and flame detection are integrated into the burner according to the invention, other designs are conceivable in which, as shown in Figure 15, one or more burners 1 extend to the reaction through a side wall over which liquid flows. In the burner 22, the burner 1 acts from the side on the toxic gas flow supplied from above through the cover.

If the reactor is to be designed with a particularly elongated configuration, it is also possible to implement a design in which the burner 1 is arranged in the middle of the lid of the reactor and the toxic gas supply members pass through the side walls of the reactor 22, as in Figure 16 Visible.

Another embodiment of the exhaust gas treatment device can be seen in FIGS. 18 to 20 . This demonstration relates to an exhaust gas treatment method having a combustion reactor with at least two burners 1 or an exhaust gas treatment device 22 thereon. In this way, if one of the burners 1 fails, the reactor 22 can continue to operate with at least one additional burner 1 .

As can be seen in Figures 18 and 19, the two burners 1 have fuel gas or oxidant supply members 37, 38 that are independent of each other, so that the fuel gas or oxidant of each burner 1 can be adjusted independently of each other by a regulating and/or control unit 39. . Furthermore, the burners 1 can also be ignited independently of each other by individual ignition devices. Each burner 1 itself has a premixing chamber 12 .

In addition, in the embodiment shown in Figures 18 to 20, each burner 1 has a flame monitoring that is separate and independent from other burners 1, wherein the flame monitoring is preferably configured so that it only detects the flame of one burner. A method that does not detect the flame of another burner 1 or the flame of the combustion reaction in the combustion reactor 22 is integrated into the burner 1 .

In the present embodiment shown in FIG. 20 , the flame monitoring is configured as an ionization electrode 40 so that the associated sensor detects the flame formation in the premixing chamber 12 of the associated burner 1 . The electrode 40 can be inserted into the flame 33 through the burner 1, preferably through the inner tube 3. When it comes to if When monitoring the flame of a dry burner 1, electrical flame monitoring can be more advantageous than optical flame monitoring because it systematically monitors the flame 33 of the associated burner 1.

A variant of the embodiment is also conceivable with a burner as shown in FIG. 10 , in which the heating wire 14 is arranged in the premixing chamber 12 and an optical sensor, in particular an IR sensor, is arranged in the combustion chamber. On the opposite end of device 1. For this variant, it is advantageous for the reactor or exhaust gas treatment device 22 to have a surface over which the water flows, at least in the viewing direction of the sensor 4 so that there are no hot surfaces in the reactor 22 that could interfere with flame detection.

If the flame 33 from a burner 1 is extinguished due to independent flame monitoring, only the fuel gas or oxidant supply of this particular burner 1 (i.e. the supply members 37 , 38 ) is blocked, which is controlled by the regulation and/or control unit 39 Finish. Other burners 1 are not affected by this.

The oxidant here can be oxygen, oxygen-enriched air or air.

As can also be seen in Figure 18, the toxic gas supply member 16 is equipped with a bypass valve 27. The fuel gas or oxidant supply means 37 , 38 have a flush gas connection 41 downstream of the last shut-off valve of the fuel gas or oxidant regulating or control unit 39 .

The exhaust gas treatment method shown in Figures 18 to 20 will be described in more detail below. A failure of one of the burners 1 is detected by the flame monitoring sensor 4 and the supply of fuel gas and oxidant is interrupted by the regulating or control unit 39 . After burner 1 fails, one of the sensor signals is compared to check whether the second or additional burner 1 is still active.

If the other burners 1 are still valid, the failed burner 1 will be re-ignited by its own ignition device without any interruption in waste gas disposal. The bypass valve 27 upstream of the reactor 22 remains connected in the direction of the reactor 22 .

If two or all burners 1 fail, a bypass valve 27 is used to feed toxic gases into a bypass 42 and provide a signal that can shut down the upstream process.

If one burner 1 fails, the fuel gas flow to the other burner 1 can be temporarily increased. When a burner 1 fails or is cut off, a flushing flow can be supplied through the burner 1 via the flushing gas connector 41 to protect the burner 1 from moisture, particles and corrosive substances.

This embodiment shown in Figures 18 and 19 provides redundancy during operation of the burner 1 to thereby avoid high downtime costs of the process plant in the event of a burner failure. The burners 1 can be arranged at any desired distance from each other and in any desired orientation, since they do not need to be used for full ignition.

1: burner

2:Outer tube

3:Inner tube

4: Sensor

5: Supply line to inner tube

6: Supply line to outer pipe

7: Insulator

8:Glass plate/quartz glass plate

9: spacer

10:Protrusion/ignition device/fork tip

11: High voltage connector/ignition device

12: Pre-mixing chamber

33: Flame

34: Tubular connector

Claims (23)

A burner (1) for generating a flame (33) for the combustion of process gases, in particular pollutants, in a combustion chamber, the burner having in each case a fuel gas and supply lines (5, 6) for oxidizing agent so that the fuel gas and the oxidizing agent flow into a premixing chamber (12), and have a function for ignition contained in the premixing chamber (12) An ignition device (10, 11) for the gas mixture, the burner (1) is characterized in that a sensor (4) for detecting and/or monitoring the flame (33) is disposed on the burner (1), in particular at one end of the burner (1) positioned opposite the premixing chamber (12), wherein the fuel gas and the oxidant can each be in a substantially cylindrical tube (2, 3) Feed into the premixing chamber (12) of the burner (1), wherein the cylindrical tubes (2, 3) are configured as outer tube (2) and inner tube (3) concentrically with respect to each other ), wherein the outer tube (2) and the inner tube (3) are arranged at a radial distance from each other, and wherein the ignition device (10, 11) has an ignition device (10, 11) arranged on the lower end of the inner tube (3) and in particular facing the outside At least one protrusion (10) is oriented, and/or the ignition device (10, 11) has an arrangement arranged on the outer tube (2) and in particular is oriented inwards to connect the inner tube (3) and the outer tube (2). ) generates at least one protrusion (35) of an ignition spark. The burner (1) of claim 1, wherein the sensor (4) is an optical sensor, especially an ultraviolet (UV) or infrared (IR) sensor, and the flame (33) falls into Within the optical field of view of the sensor (4). The burner (1) of claim 1, wherein the visual axis of the optical sensor (4) is consistent with the burner (1) The longitudinal axes generally coincide with each other. Specifically, the sensor (4) detects and monitors the flame (33) through the inner tube (3) of the burner (1). The burner (1) of claim 1, wherein a glass plate (8), especially a quartz glass plate, is arranged between the burner (1) and the sensor (4). For example, the burner (1) of claim 1, wherein the fuel gas is carried by the outer tube (2) or the inner tube (3), and the oxidant is carried by the outer tube (2) or the inner tube (3). deliver. The burner (1) of claim 1, wherein the inner tube (3) and the outer tube (2) are electrically conductive and are electrically insulated from each other by an insulator (7). The burner (1) of claim 1, wherein the sensor (4) is electrically insulated from the inner tube (3). The burner (1) of claim 1, wherein the ignition device (10, 11) has an electrode arranged in the premixing chamber (12) and used to generate an ignition spark in the premixing chamber (12). (36). The burner (1) of claim 1, wherein the outer tube (2) is electrically grounded and the inner tube (3) is connected to an ignition adapter or ignition transformer via a connector (11) for high voltage from the An ignition spark is generated from the inner tube (3) to the outer tube (2). Burner (1) as claimed in claim 8, wherein the outer tube (2) is made of electrically insulating ceramic at least in the area of the premixing chamber (12). For example, in the burner (1) of claim 1, a high temperature resistant wire (14) is disposed in the premixing chamber (12) and the high temperature resistant wire (14) protrudes to the optical sight of the sensor (4). in the domain. The burner (1) of claim 1, wherein a flame stabilizer (13) is provided in the premixing chamber (12) to generate turbulence. The burner (1) of claim 1, wherein a tubular connector (34) is provided between the outer tube (2) and the sensor (4), and the tubular connector (34) has a connection to the inner tube. The fuel gas or oxidant supply line (5) of the pipe (3). The burner (1) of claim 4, wherein the glass plate (8) with the sensor (4) is arranged at one end of a tubular connector (34) and is electrically insulated by an insulator (7) The inner tube (3) and the outer tube (2) are arranged at the other end. Burner (1) as claimed in claim 13 or 14, wherein one of the ignition means (10), in particular for high voltages, is provided between the tubular connection (34) and the outer tube (2) connector(11). An exhaust gas treatment device (22), which has at least one burner (1) as in any one of claims 1-15, the at least one burner (1) is configured in a combustion chamber (32) to generate a specific Process gas, preferably toxic gas, is burned in a flame (33), the exhaust gas treatment device (22) having at least one supply means (16) for the process gas and at least one discharge means (16) for the thermally treated exhaust gas ( 31). The exhaust gas treatment device (22) of claim 16, wherein when the burner (1) is in its assembled position, the burner (1) is positioned above the combustion chamber (32), in particular substantially perpendicular to the exhaust gas Processing device (22). An exhaust gas treatment device (22) as claimed in claim 16 or 17, wherein a supply line (1) for a flushing gas, in particular nitrogen, is provided, wherein the flushing gas can flow through the process gas supply member (16) Porous sintered elements (18) at the ends to remove particles. The exhaust gas treatment device (22) of claim 16 or 17, wherein a liquid supply line (23) is provided in particular on the side wall of the combustion chamber (32). The exhaust gas treatment device (22) of claim 16 or 17, wherein at least one supply line (25) for a reaction gas, in particular an oxidant and/or a reducing agent, is provided. Such as the exhaust gas treatment device (22) of claim 16 or 17, wherein at least two burners (1) are arranged on the combustion chamber (32), wherein each burner (1) is connected with the fuel gas or the oxidant. A separate supply component (37, 38) is associated. The exhaust gas treatment device (22) of claim 21, wherein a regulation and/or control unit (39) is provided to regulate and/or control the fuel gas or oxidant supply member (37, 38), in particular as a self-contained device configured for the combustion A function of a signal of the sensor (4) on the burner (1) for detecting and/or monitoring the flame (33) of the associated burner (1). The exhaust gas treatment device (22) of claim 21, wherein at least one sensor (4) is an ionization electrode (40).