EXHAUST GAS TREATMENT DEVICE WITH A BURNER FOR GENERATING A FLAME FOR THE COMBUSTION OF PROCESS GAS

Abstract

The invention relates to a burner as well as to a waste gas treatment device for 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.

Claims

1. A waste gas treatment device (22), comprising: a combustion chamber (32) that has at least one feed (16) through which a process gas to be thermally treated is introduced into the combustion chamber (32) and at least one discharge (31) from which thermally treated waste gases are discharged out of the combustion chamber (32); and at least one burner (1) for generating a flame (33) for the combustion of process gas in the combustion chamber (32) comprising: feed lines (5, 6) for a fuel gas and for an oxidizing agent configured so that the fuel gas and oxidizing agent flow into a pre-mixing chamber (12) to form a gas mixture, wherein each of the fuel gas and the oxidizing agent are fed into the pre-mixing chamber (12) of the burner (1) in a substantially cylindrical pipe (2, 3) configured as outer (2) and inner (3) pipes of different lengths that are concentric relative to each other with the outer pipe (2) extending axially beyond the length of the inner pipe (3), and with the fuel gas being carried in one of the outer pipe (2) or in the inner pipe (3), and the oxidizing agent being carried in the other of the outer pipe (2) or in the inner pipe (3), wherein the inner pipe (3) and the outer pipe (2) each are electrically conductive, and wherein the premixing chamber (12) is within the outer pipe (2) at or near an outlet end of the outer pipe (2), and wherein the inner pipe (3) has a lower end, an insulator (7) configured to electrically insulate the inner pipe (3) from the outer pipe (2), an ignition device (10, 11) for igniting the gas mixture contained in the pre-mixing chamber (12), wherein the ignition device (10, 11) has at least one projection (10) arranged on the lower end of the inner pipe (3) and oriented towards an outlet of the burner (1) in order to generate an ignition spark from the inner pipe (3) to the outer pipe (2) in the pre-mixing chamber (12), and a sensor (4) for detecting and/or monitoring the flame (33) arranged at one end of the burner (1) situated opposite from the pre-mixing chamber (12).

2. The waste gas treatment device (22) according to claim 1, wherein the burner (1) as assembled is situated above the combustion chamber (32), and approximately perpendicular to the waste gas treatment device (22).

3. The waste gas treatment device (22) according to claim 1 wherein a feed line for a flushing gas, especially nitrogen, is configured so that the flushing gas flows over porous sintered elements (18) at the ends of the feed means (16) for the process gas in order to displace particles.

4. The waste gas treatment device (22) according to claim 1, further comprising liquid feed lines (23) on the side wall of the combustion chamber (32).

5. The waste gas treatment device (22) according to claim 1, wherein at least one feed line (25) is provided for a reaction gas that may comprise an oxidizing agent and/or a reducing agent.

6. The waste gas treatment device (22) according to claim 1, wherein at least two burners (1) are arranged on the combustion chamber (32), and each burner (1) is associated with a separate feed (37, 38) for the fuel gas or for the oxidizing agent, respectively.

7. The waste gas treatment device (22) according to claim 1, further comprising: a regulation and/or control unit (39) to regulate and/or control the feed (37, 38) for the fuel gas or for the oxidizing agent, especially as a function of a signal from the sensor (4) that is arranged on one of the burners (1) and that serves to detect and/or monitor the flame (33) of the respective one of the burners (1).

8. The waste gas treatment device (22) according to claim 6 wherein the at least one sensor (4) is an ionization electrode (40).

9. The waste gas treatment device (22) according to claim 1, wherein the sensor (4) is an optical sensor with an optical viewing field, and wherein the flame (33) falls within the optical viewing field of the sensor (4).

10. The waste gas treatment device (22) according to claim 9, wherein the burner (1) has a longitudinal axis and wherein the optical sensor (4) has a viewing axis that coincides approximately with the longitudinal axis of the burner (1) so that the sensor (4) detects and monitors the flame (33) through the inner pipe (3) of the burner (1).

11. The waste gas treatment device (22) according to claim 9, wherein a glass pane (8) is arranged between the burner (1) and the sensor (4).

12. The waste gas treatment device (22) according to claim 1, further comprising: a tubular connecting piece (34) between the outer pipe (2) and the sensor (4) which tubular connecting piece (34) holds the feed line (5) to the inner pipe (3) for the fuel gas or for the oxidizing agent.

13. The waste gas treatment device (22) according to claim 12, wherein a glass pane (8) is arranged at one end of the substantially cylindrical connecting piece (34), and the inner pipe (3) and/or the outer pipe (2) that is electrically insulated by an insulator (7) is arranged at the other end.

14. The waste gas treatment device (22) according to claim 12, wherein the connector for the ignition device (11) is provided between the connecting piece (34) and the outer pipe (2) of the burner (1).

15. The waste gas treatment device (22) according to claim 1, wherein the burner (1) further comprises a flame holder (13) in the pre-mixing chamber (12) configured to generate turbulence.

16. The waste gas treatment device (22) according to claim 1, further comprising: a temperature-resistant wire (14) arranged in the pre-mixing chamber (12) of the burner (1) and projecting into the optical viewing field of the sensor (4).

17. The waste gas treatment device (22) according to claim 1, wherein the ignition device (10, 11) further comprises at least one projection (35) that is arranged on the outer pipe (2) and that is oriented towards the inside in order to generate an ignition spark between the inner pipe (3) and the outer pipe (2).

18. The waste gas treatment device (22) according to claim 1, wherein the ignition device (10, 11) as an alternative to the projection (10) has an electrode (36) in the pre-mixing chamber (12) of the burner (1) that is configured to generate an ignition spark in the pre-mixing chamber (12) of the burner (1).

19. The waste gas treatment device (22) according to claim 1, further comprising: a flame holder (13) in the pre-mixing chamber (12) of the burner in order to generate turbulence.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0067] The foregoing summary, as well as the following detailed description of the disclosure, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the disclosure, there is shown in the drawings embodiments which are presently preferred. It should be understood, however, that the disclosure is not limited to the precise arrangements and instrumentalities shown.

[0068] In this context, the following is shown, at times schematically:

[0069] FIG. 1 a burner with an ignition device and with a sensor,

[0070] FIG. 2 to FIG. 10 the burner as shown in FIG. 1 in various embodiments,

[0071] FIG. 11 a module for a waste gas treatment device with a burner as shown in FIG. 1 to FIG. 10,

[0072] FIG. 12 a module for the waste gas treatment device with a plunger, a sintered element and a feed line for flushing gas,

[0073] FIG. 13 a module for the waste gas treatment device with a feed line for a cleaning medium, having a nozzle,

[0074] FIG. 14 the waste gas treatment device with a quenching area as well as a discharge means for thermally treated waste gases,

[0075] FIG. 15 and FIG. 16 additional embodiments of the waste gas treatment device,

[0076] FIG. 17 a waste gas treatment device with a subsequent scrubbing station and a liquid circulation system,

[0077] FIG. 18 another embodiment of the waste gas treatment device with two burners and separate feed means,

[0078] FIG. 19 another depiction of the waste gas treatment device as shown in FIG. 18, and

[0079] FIG. 20 a burner with flame monitoring configured in the form of an ionization electrode.

DESCRIPTION OF THE DISCLOSURE

[0080] For the sake of clarity, identical components or those having the same effect are provided with the same reference numerals in the following figures, making reference to an embodiment.

[0081] FIG. 1 shows a burner 1 for generating a flame 33 for the combustion of process gas, especially contaminants, in a combustion chamber.

[0082] The feed lines 5, 6 serve to allow a fuel gas and an oxidizing agent to flow into a pre-mixing chamber 12.

[0083] An ignition device 10, 11 is provided for igniting the gas mixture present in the pre-mixing chamber 12.

[0084] FIG. 1 likewise shows a sensor 4 for detecting and/or monitoring the flame 33 that is arranged on the burner 1, especially at one end of the burner 1 situated opposite from the pre-mixing chamber 12.

[0085] As shown in FIG. 1 as well as in FIGS. 2 to 10, the fuel gas and the oxidizing agent are each fed into the pre-mixing chamber 12 of the burner 1 in an essentially cylindrical pipe 2, 3. The cylindrical pipes 2, 3 are configured as an outer pipe 2 and an inner pipe 3 that are concentric relative to each other, whereby the outer pipe 2 and the inner pipe 3 are arranged at a radial distance from each other. Depending on the application purpose, the fuel gas can be conveyed in the outer pipe 2 or in the inner pipe 3 and the oxidizing agent can be correspondingly conveyed in the outer pipe 2 or in the inner pipe 3.

[0086] In the present embodiment, the inner pipe 3 and the outer pipe 2 are electrically conductive and electrically insulated from each other by means of an insulator 7.

[0087] In the embodiment as shown in FIGS. 8, 9 and 10 as well as in FIGS. 1 to 6, the outer pipe 2 is electrically grounded and the inner pipe 3 is connected to an ignition adapter or ignition transformer via a connector 11 for high voltage in order to generate an ignition spark from the inner pipe 3 to the outer pipe 2. In this manner, an ignition spark can be systematically generated at the end of the inner pipe 3 in the transition area to the mixing chamber 12. For electric safety reasons, the outer pipe 2 should be grounded and the inner pipe 3 should carry the ignition voltage.

[0088] It can be provided for the inner pipe 3 to be configured as an electrode for measuring an ionization current in the pre-mixing chamber 12. When the inner pipe 3 is installed so as to be electrically insulated, it is not only possible for the ignition voltage to be carried through it but also for a flame signal to be generated in the form of a rectified current component by means of an applied alternating voltage—as long as there has been no ignition. Moreover, the electric detection can be employed as a redundant signal with an eye towards increasing the safety of the burner 1. As shown in FIGS. 1 to 10, for purposes of mechanically stabilizing or centering the pipes 2, 3, at least one spacer 9 can be provided between the inner pipe 3 and the outer pipe 2. These spacers 9 are configured so as to be electrically insulating, since otherwise it would not be possible to generate a spark between the pipes 2, 3.

[0089] The embodiments as shown in FIGS. 1 to 10 illustrate that a tubular connecting piece 34 is provided between the outer pipe 2 and the sensor 4, and it has the feed line 5 to the inner pipe 3 for the fuel gas or for the oxidizing agent. A glass pane 8, especially a quartz glass pane, and the sensor 4 are arranged at one end of the essentially cylindrical connecting piece 34, while the inner pipe 3 and/or the outer pipe 2, which are electrically insulated by an insulator 7, are arranged at the other end. The connecting piece 34 serves primarily to establish the electrically insulated connection of the gas feed line and of the sensor. It can be electrically grounded.

[0090] In the present embodiment, the sensor 4 is configured as an optical sensor, especially a UV or IR sensor, whereby the flame 33 falls within the viewing field of the sensor 4. The optical sensor 4 is electrically insulated vis-à-vis the inner pipe 3.

[0091] As can also be seen in FIGS. 1 to 10, the viewing axis of the sensor 4 coincides approximately with the longitudinal axis of the burner 1, so that the sensor element is aimed through the inner pipe 3. Therefore, the sensor 4 detects and monitors the flame 33 right through the inner pipe 3 of the burner 1.

[0092] The embodiment as shown in FIG. 10 illustrates that a temperature-resistant wire 14, especially a glow wire, is arranged in the pre-mixing chamber 12 and it projects into the optical viewing field of the sensor 4.

[0093] As shown in FIGS. 1 to 6 and 8 to 10, the connector 11, particularly for the high voltage that is to be applied, is provided between the connecting piece 34 and the outer pipe 2.

[0094] The ignition device 10, 11 has at least one projection 10 that is arranged on the lower end of the inner pipe 3 and that is especially oriented towards the outside.

[0095] As shown in FIG. 5, FIG. 6 and FIG. 9, it can also be provided for the ignition device 11 to have at least one projection 35 that is arranged on the outer pipe 2 and that is especially oriented towards the inside, in order to generate an ignition spark between the inner pipe 3 and the outer pipe 2.

[0096] This projection 35 can be configured so as to be, for example, prong-like or pointed, as shown in FIG. 5, or else rod-like, as shown in FIG. 6. As set forth in the invention, other geometric shapes are, of course, also conceivable. FIG. 9 shows, for example, projections 35 that are oriented upwards.

[0097] As shown in FIG. 7, the ignition device 10, 11 has an electrode 36 that is arranged in the pre-mixing chamber 12 and that serves to generate an ignition spark in the pre-mixing chamber 12. In this embodiment, the ignition voltage is not applied via a pipe 2, 3 that carries gas, but rather via the electrode 36 that is inserted in such a way as to be insulated and that opens up in the pre-mixing chamber 12, and the ignition spark is generated against the grounded inner pipe 3.

[0098] It can be provided for the outer pipe 2 to be made of electrically insulating ceramic, at least in the area of the pre-mixing chamber 12.

[0099] The embodiment as shown in FIG. 8 and FIG. 9 illustrates that a flame holder 13 can be provided in the pre-mixing chamber 12 in order to generate turbulence.

[0100] In the embodiment as shown in FIG. 1, the projection 10 is formed on the inner pipe 3 as a central projection, in contrast to which FIG. 2 shows an embodiment in which the projection 10 is formed by points or tines that are oriented towards the outside. As shown in FIG. 3, these points can run at a slant. The configuration of the projections allows the flow of gases into the pre-mixing chamber 12 and thus also allows the shape of the flame 33 to be influenced.

[0101] FIGS. 11 to 17 show a waste gas treatment device 22, or a so-called reactor, which has at least one burner 1 arranged in a combustion chamber 32 for generating a flame 33 for the combustion of process gas, preferably noxious gases. In particular, this can be a burner 1 as described above.

[0102] The waste gas treatment device 22 has at least one feed means 16 for the process gas and at least one discharge means 31 for the thermally treated gases.

[0103] In this context, the burner 1 and the noxious gas feed means 16 are integrated into a module 15. Here, for instance, the burner 1 can be positioned in the center, and the feed means 16 for the process gas can be positioned around the burner 1 in this compact module 15. This translates into a reduction in the number of screwed connections needed on the cover of the waste gas treatment device 22, and the feed means 16 for the process gas can be brought very close to the burner 1 or to the flame 33.

[0104] The design entailing a vertically installed burner simplifies the use of optical detectors that have moving parts such as, for example, closure flaps or so-called shutters for self-monitoring.

[0105] Particularly FIGS. 11 to 13 illustrate a module 15 as a part of the waste gas treatment device 22 shown in detail in FIG. 17.

[0106] As shown in FIGS. 11 to 13 as well as in FIGS. 16 and 17, when the burner 1 in its assembled position, it is situated above the combustion chamber 32, especially approximately perpendicular to the waste gas treatment device 22.

[0107] In the present embodiment as shown in FIG. 12, at least one feed line 19 is provided for a flushing gas, especially for nitrogen. The flushing gas can flow in over porous sintered elements 18 at the ends of the feed means 16 for the process gas in order to displace particles. Especially at the outlet leading into the waste gas treatment device, deposits build up due to returning moisture, oxidant or even due to heat, and these can be flushed away with the flushing gas.

[0108] The typical applications make use of gases that, when heated or reacted with oxygen or moisture, form solids that can be deposited on all surfaces. Mechanical cleaning implements such as, for instance, scrapers, can be employed to remove such deposits from the interior surfaces of the reactor. These implements, however, are susceptible to malfunction. For this reason, the burner 1 according to the invention is preferably used in a reactor or in a waste gas treatment device 22 having a wall over which liquid flows.

[0109] As shown in FIGS. 14 to 17, liquid feed means 23 are provided, especially on the side wall of the combustion chamber 32, for the waste gas treatment device 22 or for the reactor over whose wall a liquid flows. In order to protect the feed means 16 for the process gas or the noxious gas inlets from splashing liquid, a small collar 24 can be installed on the side wall in front of the liquid feed lines 23, as can be seen in FIGS. 14 to 16.

[0110] For better thermal insulation, the cover of the waste gas treatment device 22 can be configured with a double wall. An elevated surface temperature on the inside of the cover reduces the probability that deposits of solids will build up. A flushing gas such as, for instance, nitrogen can be fed in through the double-walled cover, and this gas flows over porous sintered elements at the ends of the noxious gas feed lines in order to displace particles.

[0111] According to the embodiment shown in FIG. 13, it is provided for a nozzle 20 to be installed in the noxious gas inlet 16 and, at certain points in time or if the pressure rises in the noxious gas line 16, it generates a gas pulse to blast away deposits on the wall. Cleaning with a liquid jet from a nozzle 20 installed in the noxious gas inlet 16 on a feed means 21 for cleaning media is also possible. In order to prevent deposits on the cover of the waste gas treatment device 22, a flushing gas can flow in from the edge of the cover all the way to the middle of the cover.

[0112] Even though the burner 1 allows a variation of the fuel gas-oxidant ratio, for certain processes it might be necessary to feed additional oxidant, for instance, air or oxygen or a reducing agent such as fuel gas, into the combustion chamber 32. Such feed lines 25 for reaction gases can be installed in the cover of the reactor 22.

[0113] As shown in FIG. 15, there is at least one feed line 25 for a reaction gas, especially for an oxidizing agent and/or a reducing agent.

[0114] It can be seen in FIG. 14 that the discharge means 31 for the thermally treated waste gases of the waste gas treatment device 22 opens up into a quenching area 30 for purposes of quickly cooling off the gas after the combustion.

[0115] FIG. 17 shows a scrubbing station that has a wet scrubber 26, a heat exchanger 28 and a pump 29 and that is downstream from the waste gas treatment device 22. In this washing station, soluble gases and also particles such as, for instance, solids and acids formed during the combustion, are scrubbed out with a scrubbing liquid. The scrubbing liquid is conveyed by means of the pump 29 into the scrubbing segment and into the waste gas treatment device via the heat exchanger 28 and via means—not shown here—for regulating and measuring the throughput flow, and the scrubbing liquid then flows back into a storage tank. The storage tank has feed lines for fresh water and for alkaline solution for regulating the pH value and a drain for emptying purposes as well as sensors for the filling level, for the pH value and for the temperature. The scrubbing station can be connected to exhaust unit so a negative pressure can be generated in the waste gas treatment device 22.

[0116] Thanks to the compact design of the burner, configurations with several burners 1 on a waste gas treatment device 22 or on a reactor are also possible. For this purpose, for instance, the noxious gas feed means 16 are arranged in the middle of the reactor cover, and two or more burners 1 are arranged along an outer circle around these feed means, preferably with a slight slant of the flame 33 towards the middle. The burners 1 can also be slanted in such a way that they create an eddy in the reactor 22, thus allowing a more stable flow and better mixing in the reactor 22. FIGS. 14 and 15 show embodiments with two burners 1. Several, especially two, burners 1 are also provided in the embodiments shown in FIGS. 18 to 20.

[0117] Since the ignition and flame detection are integrated into the burner according to the invention, other designs are conceivable in which, as shown in FIG. 15, one or more burners 1 extend into the reactor 22 through the side wall over which a liquid flows, said burners 1 acting from the side upon the noxious gas stream that is fed in from above through the cover.

[0118] If the reactor is to be designed with a particularly slender configuration, it is also possible to implement a design in which the burner 1 is arranged in the middle of the cover of the reactor, and the noxious gas feed means passes through the side wall of the reactor 22, as can be seen in FIG. 16.

[0119] Another embodiment of the waste gas treatment device can be seen in FIGS. 18 to 20. This shows a method for waste gas disposal involving a combustion reactor or a waste gas treatment device 22 on which there are at least two burners 1. In this manner, if one of the burners 1 fails, the reactor 22 can continue to operate with at least one additional burner 1.

[0120] As can be seen in FIG. 18 and FIG. 19, the two burners 1 have feed means 37, 38 for the fuel gas or the oxidizing agent that are independent from each other, so that the fuel gas or the oxidizing agent for each burner 1 can be regulated independently of each other by means of a regulation and/or control unit 39. Moreover, the burners 1 can also be ignited independently of each other by means of separate ignition devices. Each burner 1 has its own pre-mixing chamber 12.

[0121] Furthermore, each burner 1 in the embodiments shown in FIGS. 18 to 20 has flame monitoring that is separate and independent from the other burners 1, whereby the flame monitoring is preferably integrated into the burner 1 in such a way that it detects only the flame of the one burner but not the flame of the other burner 1 or of the combustion reaction in the combustion reactor 22.

[0122] In the present embodiment as shown in FIG. 20, the flame monitoring is configured as an ionization electrode 40 so that the appertaining sensor detects the flame formation in the pre-mixing chamber 12 of the associated burner 1. The electrode 40 can be inserted through the burner 1, preferably through the inner pipe 3, into the flame 33. When it comes to the flame monitoring of several burners 1, electric flame monitoring can be more advantageous than optical flame monitoring since it systematically monitors the flame 33 of the associated burner 1.

[0123] It is also conceivable to have an embodiment variant with a burner as shown in FIG. 10, whereby the glow wire 14 is arranged in the pre-mixing chamber 12, and an optical sensor, especially an IR sensor, is arranged on the opposite end of the burner 1. For this variant, it is advantageous for the reactor or the waste gas treatment device 22 to have a surface over which water flows, at least in the viewing direction of the sensor 4, so that no glowing surface in the reactor 22 can interfere with the flame detection.

[0124] If the flame 33 from a burner 1 is extinguished, thanks to the independent flame monitoring, only the supply of fuel gas or oxidizing agent—that is to say, the feed means 37, 38—for this particular burner 1 is blocked, which is done by means of the regulation and/or control unit 39. The other burners 1 are not affected by this.

[0125] The oxidant here can be oxygen, oxygen-rich air, or air.

[0126] As can likewise be seen in FIG. 18, the noxious gas feed means 16 are equipped with a bypass valve 27. The feed means 37, 38 for the fuel gas or for the oxidizing agent has a flushing gas connector 41 downstream from the last shut-off valve of the regulation or control unit 39 for the fuel gas or for the oxidizing agent.

[0127] The method for waste gas disposal as shown in FIGS. 18 to 20 will be described in greater detail below. A failure of a burner 1 is detected by means of the sensor 4 of the flame monitoring, and the feed of fuel gas and oxidizing agent is interrupted by the regulation or control unit 39. After the failure of the burner 1, a comparison of the sensor signals serves to check whether the second or additional burners 1 is/are still active.

[0128] In the eventuality that other burners 1 are still active, the burner 1 that has failed is re-ignited by means of its own ignition device, without any interruption in the waste gas disposal. The bypass valve 27 upstream from the reactor 22 remains connected in the direction of the reactor 22. If both or all of the burners 1 have failed, the bypass valve 27 is deployed to feed the noxious gas into a bypass 42 and a signal is provided with which the upstream process can be switched off.

[0129] In the case of a failure of a burner 1, the fuel gas stream to the other burner 1 can be temporarily increased. When a burner 1 fails or is switched off, a flushing stream can be fed via the flushing gas connector 41 through this burner 1 in order to keep the burner 1 free of moisture, particles and corrosive substances.

[0130] This embodiment shown in FIGS. 18 and 19 provides redundancy during the operation of the burner 1, thus avoiding high downtime costs for the process plants when a burner malfunctions. The burners 1 can be arranged at any desired distance from each other and in any desired orientation since they are not required for through-ignition.

LIST OF REFERENCE NUMERALS

[0131] 1 burner [0132] 2 outer pipe [0133] 3 inner pipe [0134] 4 sensor [0135] 5 feed line to the inner pipe [0136] 6 feed line to the outer pipe [0137] 7 insulator [0138] 8 glass pane/quartz glass pane [0139] 9 spacer [0140] 10 projection [0141] 11 connector for high voltage [0142] 12 pre-mixing chamber [0143] 13 flame holder [0144] 14 glow wire [0145] 15 module [0146] 16 feed means for process gas [0147] 18 sintered element [0148] 19 feed line for flushing gas [0149] 20 nozzle [0150] 21 feed means for cleaning medium [0151] 22 waste gas treatment device [0152] 23 liquid feed means [0153] 24 collar [0154] 25 feed line for reaction gases [0155] 26 wet scrubbers [0156] 27 bypass valve [0157] 28 heat exchanger [0158] 29 pump [0159] 30 quenching area [0160] 31 discharge means for thermally treated waste gases [0161] 32 combustion chamber [0162] 33 flame [0163] 34 tubular connecting piece [0164] 35 projection of the outer pipe [0165] 36 electrode [0166] 37 feed means [0167] 38 feed means [0168] 39 regulation and/or control unit [0169] 40 ionization electrode [0170] 41 flushing gas connector [0171] 42 bypass