JP4526366B2 - Sampling device for exhaust gas analysis - Google Patents

Description

  The present invention relates to an exhaust gas analysis sampling apparatus that samples and analyzes dust-containing exhaust gas generated in an incinerator or melting furnace.

  Conventionally, as a sampling device for exhaust gas generated in a garbage incinerator, melting furnace, etc., a sampling device for sampling a waste gas around the furnace wall by attaching a sampling means such as a sampling probe to the furnace wall is known. (For example, refer to Patent Documents 1 to 3.)

  However, in the sampling devices as described in Patent Documents 1 and 2, if the filter (filter paper, wire mesh filter, etc.) of the gas sampling means is clogged by dust in the exhaust gas, sampling becomes impossible. Therefore, there is a problem that the exhaust gas sampling and analysis must be interrupted because it is necessary to periodically replace the filter or remove dust. Further, although the sampling device as described in Patent Document 3 has backwashing means for removing dust adhering to the filter, it has only one exhaust gas collecting means. There is a problem that sampling and analysis of exhaust gas must be interrupted during backwashing. In addition, any of the sampling devices described in Patent Documents 1 to 3 can collect only the exhaust gas around the furnace wall, and there is a problem that the analysis result of the exhaust gas is biased. Therefore, in order to cope with these problems, in Patent Document 4, a plurality of heat-resistant porous ceramic filters are arranged so as to protrude into the furnace, and a wide range of exhaust gas sampling in the furnace is not biased. In addition, an exhaust gas analyzer (hereinafter referred to as a conventional device) that is continuously performed has been proposed.

  As shown in FIG. 4, the conventional apparatus 100 includes two sampling tubes 102a and 102b having cylindrical porous ceramic filters 101a and 101b at their ends. Here, the sampling tubes 102a and 102b are fixed to the furnace wall 103 so that the ceramic filters 101a and 101b protrude into the furnace.

  Extraction tubes 104a and 104b are connected to the base ends of the sampling tubes 102a and 102b, respectively. The extraction tubes 104a and 104b are joined to a single junction tube 105 and connected to a drain bin 106. An analyzer 107 is connected to 106. Further, exhaust solenoid valves 104a ′ and 104b ′ are provided slightly before the junction pipe 105 of the extraction pipes 104a and 104b, respectively.

  The extraction pipes 104a and 104b are respectively branched into compressed fluid introduction pipes 108a and 108b through which compressed fluid electromagnetic valves 108a ′ and 108b ′ are inserted, respectively, on the front side of the exhaust gas solenoid valves 104a ′ and 104b ′. These compressed fluid introduction pipes 108 a and 108 b are connected to a compressed fluid supply source 109.

  In such a configuration, the exhaust gas flowing in the furnace is sampled and collected by the ceramic filters 101a and 101b in a wide range in the furnace, and is introduced into the sampling tubes 102a and 102b. The exhaust gas introduced into the sampling tubes 102a and 102b is introduced into the analyzer 107 via the extraction tubes 104a and 104b, the merging tube 105 and the drain bin 106, and is analyzed by the analyzer 107.

  As the exhaust gas is sampled, dust adheres to the surfaces of the ceramic filters 101a and 101b. The dust is removed as follows.

  First, the exhaust gas solenoid valve 104a ′ of either one of the extraction pipes (104a) is closed to block the flow of the exhaust gas sampled by the sampling pipe 102a in the extraction pipe 104a, and from the extraction pipe 104a. The compressed fluid electromagnetic valve 108a ′ of the compressed fluid introduction pipe 108a to be branched is opened.

  Then, the compressed fluid supplied from the compressed fluid supply source 109 is supplied to the internal space of the ceramic filter 101a through the compressed fluid introduction tube 108a, the extraction tube 104a, and the sampling tube 102a, and adheres to the surface of one ceramic filter 101a. Dust is removed. At this time, the exhaust gas in the furnace is sampled by the other ceramic filter 101b and sampling tube 102b.

  After the required time has elapsed, the exhaust gas solenoid valve 104a ′ is opened, the compression fluid solenoid valve 108a ′ is closed, the exhaust gas solenoid valve 104b ′ is closed, and the compression fluid solenoid valve 108b ′ is opened. . In this way, the dust removal of the other ceramic filter 101b is performed this time, and the exhaust gas in the furnace is sampled by the ceramic filter 101a and the sampling pipe 102a. As described above, in the conventional apparatus 100, by providing a plurality of ceramic filters 101a and 101b and alternately removing the deposits, the dust of the ceramic filter 101a (101b) is collected without interrupting the sampling of the exhaust gas. Removal can be performed.

Japanese Patent Laid-Open No. 10-90139 JP 2000-227389 A JP 2002-131198 A JP 2002-139409 A

  However, according to the conventional apparatus 100, although the amount for purging is small, a gas having a component different from the exhaust gas flows into the furnace, which may cause fluctuations in the combustion state. .

  Further, since the conventional apparatus 100 employs a method of alternately removing the dust from the ceramic filters 101a and 101b, a plurality of extraction tubes 104a and 104b are required, and the apparatus configuration is complicated and expensive. There is a problem.

  In addition, when performing highly responsive combustion control, it is preferable to place the ceramic filter 101a (101b) close to the exhaust gas generation source and sample and analyze the exhaust gas immediately after generation. However, when the ceramic filters 101a and 101b are arranged at positions close to the exhaust gas generation source, highly adhesive dust that has been melted by a high temperature atmosphere adheres to the outer surfaces of the ceramic filters 101a and 101b. There is a problem that the dust removing means (compressed fluid supply source 109 or the like) cannot sufficiently remove the dust. For this reason, even when performing highly responsive combustion control, the ceramic filters 101a and 101b have to be arranged at positions away from the exhaust gas generation source.

  The present invention has been made in order to solve such problems, can suppress fluctuations in the combustion state in the furnace, can simplify the configuration of the apparatus and reduce the cost, and can be tacky. It is an object of the present invention to provide an exhaust gas analysis sampling apparatus capable of reliably removing an adhering substance even when a high adhering substance is attached.

In order to achieve the above object, a sampling apparatus for exhaust gas analysis according to the first invention comprises:
A heat-resistant porous filter that protrudes from the furnace or flue and samples the exhaust gas in the furnace or flue, a negative pressure chamber into which the exhaust gas sampled by the porous filter is introduced, and sampling by the porous filter A sampling gas supply pipe for supplying a part of the exhausted gas to the gas analysis unit, and a porous gas filter disposed in the vicinity of a base end of the porous filter in the negative pressure chamber toward the internal space of the porous filter, An exhaust gas analyzer comprising an adhering substance removing means for removing the adhering substance adhering to the filter,
The deposit removing means includes a fluid ejection nozzle that ejects fluid toward the porous filter, and the nozzle is provided with a cylindrical fluid guide portion at the tip of a Laval nozzle portion. It is characterized in that a long and narrow opening is formed in the part in the fluid flow direction.

Next, the sampling apparatus for exhaust gas analysis according to the second invention is:
A heat-resistant porous filter that protrudes from the furnace or flue and samples the exhaust gas in the furnace or flue, a negative pressure chamber into which the exhaust gas sampled by the porous filter is introduced, and sampling by the porous filter A sampling gas supply pipe for supplying a part of the exhausted gas to the gas analysis unit, and a porous gas filter disposed in the vicinity of a base end of the porous filter in the negative pressure chamber toward the internal space of the porous filter, An exhaust gas analyzer comprising an adhering substance removing means for removing the adhering substance adhering to the filter,
The deposit removing means includes a shock wave generating electrode that receives a pulse voltage and generates a shock wave toward the porous filter.

In the first or second aspect, wherein the pressure detecting means for detecting the internal pressure of the negative pressure chamber is provided, wherein the deposit removing means, the negative pressure of the negative pressure chamber by the pressure detecting means is equal to or higher than a predetermined value When it is detected that the pressure has increased, it is preferably activated, and when the negative pressure is less than a predetermined value, it is preferably deactivated (third invention).

  In the third aspect of the present invention, it is preferable that a communication passage communicating the negative pressure chamber and the furnace or the flue, and an eject air injection means for injecting eject air into the furnace or the flue via the communication passage are provided. (4th invention).

  According to the first aspect of the present invention, the deposit removing means includes a nozzle having a Laval nozzle portion and a fluid guide portion, and an elongated opening is formed in the fluid guide portion in the fluid flow direction. Therefore, a supersonic fluid (air) with a straight traveling shock wave can be ejected from the nozzle toward the porous filter, so that a very small amount of fluid can be ejected in a very short time. The deposit on the quality filter can be efficiently removed, and the running cost for removing the deposit can be suppressed.

  In addition, since only a small amount of fluid is injected, it is possible to suppress fluctuations in the combustion state in the furnace. Furthermore, since the fluid ejection time at the time of deposit removal is short, in other words, the deposit removal can be completed in a very short time, so that it is possible to sample the exhaust gas substantially continuously by a single porous filter. Accordingly, it is not necessary to provide a plurality of exhaust gas collecting sections and a plurality of extraction pipes as in the conventional one, and the apparatus configuration can be simplified.

  In addition, because the deposit removal efficiency is good, even if a sticky deposit adheres to the porous filter, the deposit can be reliably removed. As a result, the position of the porous filter can be adjusted. It becomes possible to approach the generation source of the exhaust gas, and the exhaust gas immediately after the generation can be sampled.

  According to the second aspect of the present invention, the deposit on the porous filter is removed by the shock wave generated by the electrical energy, so that the fluid for removing the deposit is not ejected. As a result, fluctuations in the combustion state can be prevented.

  According to the third aspect of the present invention, when the negative pressure in the negative pressure chamber detected by the pressure detection means increases to a predetermined value or more, that is, dust adheres to the porous filter and the exhaust gas introduced into the negative pressure chamber Since the method of operating the deposit removing means is employed only when the flow rate is reduced by a certain level or more, the operation of the deposit removing means can be minimized, and the running cost for removing the deposit is required. There is an effect that can be reduced. If the configuration of the fourth invention is adopted, the negative pressure chamber can be maintained at a negative pressure with a very simple configuration, which can contribute to further reduction in running cost.

  Next, specific embodiments of the sampling apparatus for exhaust gas analysis according to the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 is a schematic configuration diagram of a sampling apparatus for exhaust gas analysis according to the first embodiment of the present invention, and FIG. 2 is a sectional view of a nozzle according to the first embodiment (a) and FIG. AA sectional view (b) is shown respectively.

  A sampling apparatus for exhaust gas analysis (hereinafter referred to as “sampling apparatus”) 1 according to the present embodiment is attached so as to project outward from a furnace wall 2 ′ of an incinerator 2 as shown in FIG. A negative pressure chamber 4 fixed to the part 3 and maintained at a negative pressure inside, and attached to the front surface (incinerator 2 side) of the negative pressure chamber 4 so as to protrude into the incinerator 2 and incinerator 2 is provided with a heat-resistant porous cylindrical ceramic filter (porous filter) 5 that collects dust by sampling the exhaust gas in 2.

  The ceramic filter 5 is closed at the front end and opened at the base end so that the internal space and the internal space of the negative pressure chamber 4 communicate with each other. The ceramic filter 5 samples and collects dust. The exhaust gas introduced into its own internal space is guided into the negative pressure chamber 4. A sampling gas supply pipe 6 for supplying a part of the exhaust gas sampled by the ceramic filter 5 to a gas analyzer (not shown) is disposed in the internal space of the ceramic filter 5 and the negative pressure chamber 4.

  The negative pressure chamber 4 is provided with a pressure detector (pressure detection means) 7 for detecting the internal pressure of the negative pressure chamber 4. This pressure detector 7 is electrically connected to an electromagnetic valve 14 ′ inserted in a pressurized air supply pipe 14, which will be described later, and based on pressure detection data in the negative pressure chamber 4, opening / closing control of the electromagnetic valve 14 ′ is performed. The function to perform is provided.

  On the other hand, an ejector 8 for injecting eject air into the incinerator 2 is provided below the negative pressure chamber 4. The ejector 8 is disposed horizontally below the negative pressure chamber 4 and has a horizontal pipe 9a whose front end is fixed to the furnace wall 2 'and opens into the incinerator 2, and the horizontal pipe 9a and the negative pressure chamber. 4 is connected to a supply source of eject air (in this embodiment, an air header pipe 12 to be described later), and a distal end portion is arranged in the horizontal pipe 9a. An eject air injection pipe (eject air injection means) 10 for injecting eject air from the tip portion toward the incinerator 2 is provided. The horizontal pipe 9a and the connecting pipe 9b correspond to the communication path of the present invention. According to the ejector 8 configured in this manner, the exhaust air in the negative pressure chamber 4 is drawn by ejecting the eject air from the eject air injection pipe 10 into the horizontal pipe 9a. Chamber 4 is maintained at a negative pressure. In the figure, reference numeral 10 'denotes a needle valve for adjusting the ejection amount of eject air.

  In the present embodiment, the sampling device 1 is provided with a dust removing unit (attached matter removing means) 11 for removing dust (attached matter) adhering to the outer surface of the ceramic filter 5 as the exhaust gas is collected. ing. The dust removing unit 11 is arranged toward the internal space of the ceramic filter 5 in the vicinity of the air header pipe 12 as a pressurized air supply source and the base end portion of the ceramic filter 5 in the negative pressure chamber 4. In addition, a nozzle 13 for injecting nozzle injection gas toward the internal space of the ceramic filter 5 and a pressurized air supply with an electromagnetic valve 14 ′ for supplying pressurized air from the air header pipe 12 to the nozzle 13. A tube 14 is provided. The compressed air is supplied from the air header pipe 12 to the nozzle 13 and the nozzle injection gas is injected into the ceramic filter 5 so that dust on the outer surface of the ceramic filter 5 is removed. Yes.

  As shown in FIG. 2A, the nozzle 13 has a cylindrical outer tube 20 and a Laval nozzle portion 21 that is attached to the proximal end portion inside the outer tube 20. The Laval nozzle portion 21 has a distal end portion formed slightly smaller than the inner diameter of the outer tube 20 and a proximal end portion formed substantially the same diameter as the inner diameter of the outer tube 20. The Laval nozzle portion 21 is inserted from the base end side of the outer tube 20 and is supported by the outer tube 20 by being welded to the outer tube 20 at the base end portion.

  Here, the Laval nozzle refers to a medium-thinned nozzle whose middle part is squeezed into a throat. According to such a Laval nozzle, when the air pressure on the base end side is made higher than the air pressure on the tip end side, and the fluid velocity at the throat becomes the sonic velocity, air accompanied by a supersonic shock wave from the tip portion. It is known to be jetted.

  In the present embodiment, the diameter of the throat S is set so that the air velocity at the throat S of the Laval nozzle portion 21 becomes a sonic speed, that is, supersonic pressurized air is injected from the tip of the Laval nozzle portion 21. The distance from the base end of the Laval nozzle portion 21 to the throat S, the distance from the throat S to the tip end of the Laval nozzle portion 21, the diameter of the base end portion opening and the tip end opening of the Laval nozzle portion 21, the base end portion of the Laval nozzle portion 21 The air pressure and the like supplied to the are appropriately adjusted.

  A fluid guide portion 22 is provided at the front end of the Laval nozzle portion 21 at the distal end portion of the outer tube 20. A plurality of elongated suction holes (openings) 23 are formed in the fluid guide portion 22 in the circumferential direction of the outer tube 20 at an equal pitch in the axial direction of the nozzle 13. These suction holes 23 are formed at the side of the nozzle 13 when nozzle injection gas (pressurized air after injection from the Laval nozzle part 21; indicated by symbol a in FIG. 2A) is injected from the Laval nozzle part 21. The air is sucked to form a flow of air (indicated by reference numeral b in FIG. 2A) surrounding the nozzle injection gas a, and the nozzle injection gas a is imparted with a straightness. . In addition, when there is no injection of the nozzle injection gas from the Laval nozzle portion 21, it plays a role of a flow hole for the exhaust gas introduced from the internal space of the ceramic filter 5 into the negative pressure chamber 4. On the other hand, on the base end side of the outer tube 20, a screw portion 24 for attaching the nozzle 13 to the distal end portion of the pressurized air supply tube 14 is provided.

  According to the sampling apparatus 1 configured as described above, the exhaust gas in the vicinity of the ceramic filter 5 is sampled and collected by the ceramic filter 5 due to the pressure difference between the negative pressure chamber 4 and the internal space of the incinerator 2. 5 is introduced into the interior space. In this way, most of the exhaust gas introduced into the ceramic filter 5 is guided to the negative pressure chamber 4 and then drawn into the horizontal pipe 9 a by the ejection of eject air from the ejector 8. However, a part of the gas is supplied to the gas analyzer through the sampling pipe 6. The gas analyzer analyzes the sampled exhaust gas, and the analysis result is used as an index for various controls (combustion control, air supply control, etc.).

  If sampling of the exhaust gas in the incinerator 2 is continuously performed, dust or the like in the exhaust gas adheres to the outer peripheral surface of the ceramic filter 5 and hinders the introduction of the exhaust gas, thereby hindering the analysis of the exhaust gas. become. Therefore, the following dust removal operation is performed to remove dust and the like attached to the outer peripheral surface of the ceramic filter 5.

  When dust in the exhaust gas adheres to the outer peripheral surface of the ceramic filter 5, the exhaust gas from the ceramic filter 5 into the negative pressure chamber 4 is reduced, while the exhaust gas in the negative pressure chamber 4 is ejected from the eject air. Therefore, the negative pressure in the negative pressure chamber 4 gradually increases. When the negative pressure increases to a predetermined value or more, it is determined that “the dust on the outer peripheral surface of the ceramic filter 5 needs to be removed”, and the electromagnetic valve 14 ′ is automatically opened, Pressurized air is supplied to the nozzle 13. Then, a supersonic nozzle injection gas a excellent in straightness with a shock wave is injected from the nozzle 13 toward the internal space of the ceramic filter 5, and the ceramic filter 5 is combined by the combined action of the nozzle injection gas a and the shock wave. Dust and the like adhering to is removed. Note that when the nozzle injection gas a is being injected from the nozzle 13, the sampling of the exhaust gas is temporarily suspended.

  By the injection of the nozzle injection gas a, dust on the outer peripheral surface of the ceramic filter 5 is removed, the amount of exhaust gas flowing into the negative pressure chamber 4 via the ceramic filter 5 is increased, and the negative pressure in the negative pressure chamber 4 is increased. When it recovers below a predetermined value, it is determined that “the state of the ceramic filter 5 has been restored to a normal state”, and the electromagnetic valve 14 ′ is automatically closed. Thereby, the supply of the pressurized air to the nozzle 13 is stopped, and the sampling of the exhaust gas is restarted.

  In this embodiment, the nozzle 13 having the Laval nozzle portion 21 is injected with a supersonic nozzle injection gas a having a straight wave with a shock wave toward the internal space of the ceramic filter 5, and the dust adhered to the ceramic filter 5. Can be efficiently removed, so that the injection amount of the nozzle injection gas a is small, the running cost for dust removal can be reduced, and the pressurized air source (air header pipe 11 etc.) can be made compact. Can be achieved.

  In addition, in this embodiment, based on the negative pressure in the negative pressure chamber 4 detected by the pressure detector 7, it is determined whether or not it is necessary to remove the dust from the ceramic filter 5, and the dust is removed. Only when it is determined that it is necessary, the pressurized air is supplied to the nozzle 13 to remove dust from the ceramic filter 5. And the running cost can be further reduced. In addition, since the amount of nozzle injection gas (pressurized air) flowing into the incinerator 2 is greatly reduced, it is possible to prevent fluctuations in the combustion state in the incinerator 2, It is possible to reduce the burden on exhaust gas treatment equipment such as an air attractor installed on the downstream side of the incinerator 2.

  Further, in the present embodiment, the dust of the ceramic filter 5 can be efficiently removed, so that the time required for the removal operation, that is, the sampling interruption time can be made extremely short. Therefore, even when the exhaust gas is sampled by a single ceramic filter 5, it is possible to sample the exhaust gas substantially continuously. Therefore, like the conventional one, a plurality of sampling tubes and each sampling tube are analyzed. Since a plurality of pipes connecting the devices are not necessary, the configuration of the sampling device can be simplified and the number of parts can be reduced.

  Furthermore, since the sampling apparatus 1 of the present embodiment is excellent in dust removal efficiency as described above, even when highly adhesive dust adheres to the outer peripheral surface of the ceramic filter 5, the adhesiveness is high. Dust can be removed satisfactorily. Therefore, the arrangement position of the ceramic filter 5 can be brought close to the exhaust gas generation source side, and the exhaust gas sampling and analysis immediately after the generation can be continuously performed. Therefore, it is particularly suitable for use in the case of performing combustion control that requires high responsiveness and analyzing exhaust gas immediately after generation.

  Furthermore, in the present embodiment, a configuration is adopted in which the negative pressure chamber 4 is made negative pressure by ejecting eject air from the ejector 8, so that the negative pressure is lower in cost than that using a pump. The chamber 4 can be maintained at a negative pressure.

  In the present embodiment, a double tube structure nozzle 13 having a cylindrical outer tube 20 and a Laval nozzle 21 disposed inside the outer tube 20 is used, but the base end side is formed in a thin shape. As long as the fluid guide part that improves the straightness of the jet air is provided at the tip part, other types of nozzles such as an integrally formed nozzle may be used. Even in this case, the same effect can be obtained.

  Next, in order to confirm the performance of the dust removing unit 11 of the present embodiment, the dust removing unit 11 of the present embodiment and a dust removing unit as a comparison target are prepared, and the ceramic filter 5 of each dust removing unit is prepared. A test was performed to detect the surface pressure of the ceramic filter 5 by injecting nozzle injection gas toward the internal space. The test results are summarized in Table 1. Here, the dust removal unit as the comparison object uses a normal nozzle having neither the Laval nozzle unit 21 nor the fluid guide unit 22, and other configurations such as a negative pressure chamber are the present embodiment. The dust removing unit 11 has the same configuration.

  As apparent from Table 1, the sampling device 1 of the present embodiment has a surface of the ceramic filter 5 in spite of setting the injection time of the nozzle injection gas to one tenth of that of the device using a normal nozzle. It can be seen that the pressure is about 10 times. From this, the sampling apparatus 1 of this embodiment uses the nozzle which has the Laval nozzle part 21 and the fluid guide part 22, and thereby the deposit | attachment of the ceramic filter 5 is far more efficient than what used the normal nozzle. It became clear that it could be removed.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to the drawings.

  FIG. 3 shows a schematic configuration diagram (upper half) of the shock wave generating electrode according to the second embodiment and a circuit diagram (lower half) of the pulse voltage supply unit. In this embodiment, the configuration is basically the same as that of the first embodiment except that a probe and a pulse voltage supply unit are used instead of the nozzle 13 and the pressurized air supply pipe 14 of the first embodiment. Therefore, only the probe and the pulse voltage supply unit will be mainly described, and description of other parts will be omitted.

  In the present embodiment, a probe (shock wave generating electrode) 30 for generating a shock wave from the front end portion is directed toward the internal space of the ceramic filter 5 in the vicinity of the base end portion of the ceramic filter 5 in the negative pressure chamber 4. A pulse voltage supply unit 31 for supplying a pulse voltage to the probe 30 is provided outside the negative pressure chamber 4.

  As shown in FIG. 3, the pulse voltage supply unit 31 is arranged in parallel with an AC power supply 32, a voltage-adjusting slidac 33, a transformer 34, a rectifier 35, a charging resistor 36, and a resistor 37. The amplitude and frequency of the pulse voltage output to the probe 30 are mainly adjusted by adjusting the resistance value of the resistor 37 and the electric capacity of the capacitors 38A and 38B. Can be adjusted appropriately. In addition, the code | symbol 38 in FIG. 3 is a voltmeter, and the code | symbol 40 is an ammeter.

  On the other hand, the probe 30 has an inner conductor (conductive wire) 45 arranged in the axial direction of the probe 30 and a cylindrical outer conductor arranged on the outer periphery of the inner conductor 45 at a predetermined interval in the central shaft portion. 46 and an insulator 47 interposed between the inner conductor 45 and the outer conductor 46 except for the tip of the probe 30. Here, the inner conductor 45 and the outer conductor 46 are respectively connected to the pulse voltage supply unit 31.

  According to the probe 30 configured in this way, by receiving the supply of the pulse voltage from the pulse voltage supply unit 31, the distal end portion 45 ′ of the inner conductor 45 without the insulator 47 and the distal end of the outer conductor 46. A discharge is generated between the portion 46 'and a shock wave SW is generated by this discharge. This shock wave SW advances toward the internal space of the ceramic filter 5 and gives an impact to the ceramic filter 5, whereby dust adhering to the outer peripheral surface of the ceramic filter 5 is removed.

  According to the present embodiment, the dust of the ceramic filter 5 is removed by the shock wave SW generated by the electrical energy, so that pressurized air for dust removal is not supplied into the incinerator 2. Therefore, fluctuations in the combustion state in the incinerator 2 can be prevented more reliably, and the burden on the exhaust gas treatment equipment such as an air attractor installed downstream of the incinerator 2 can be further reduced. .

  Also in the present embodiment, the dust of the ceramic filter 5 can be efficiently removed by the shock wave SW, so that the exhaust gas can be substantially continuously analyzed by one ceramic filter 5 as in the first embodiment. Therefore, the configuration of the sampling device 1 can be simplified.

  In the second embodiment, as in the first embodiment, a method of generating a shock wave SW by supplying a pulse voltage to the probe 30 only when the negative pressure in the negative pressure chamber 4 increases beyond a predetermined value. Can be taken.

  In each of the above embodiments, the example of sampling the exhaust gas in the incinerator 2 using the sampling device has been described. However, the sampling device is installed in the ash melting furnace, the flue, etc., and the ash melting furnace, the flue, etc. Of course, it is possible to analyze the exhaust gas flowing in the interior space of the chamber.

1 is a schematic configuration diagram of a sampling apparatus for exhaust gas analysis according to a first embodiment of the present invention. Sectional drawing (a) of the nozzle which concerns on 1st Embodiment, and AA sectional view taken on the line of Fig.2 (a) The schematic block diagram (upper half part) of the probe which concerns on 2nd Embodiment of this invention, and the circuit diagram of a pulse voltage supply part (lower half part) Schematic configuration diagram of a conventional sampling device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sampling apparatus for exhaust gas analysis 2 Incinerator 4 Negative pressure chamber 5 Ceramic filter 6 Sampling pipe 7 Pressure detector 8 Ejector 9a Horizontal pipe 9b Connecting pipe 10 Eject air injection pipe 11 Dust removal part 12 Header pipe 13 Nozzle 14 'Electromagnetic valve 21 Laval nozzle part 22 Fluid guide part 23 Suction hole 30 Probe 31 Pulse voltage supply part

Claims (4)

A heat-resistant porous filter that protrudes from the furnace or flue and samples the exhaust gas in the furnace or flue, a negative pressure chamber into which the exhaust gas sampled by the porous filter is introduced, and sampling by the porous filter A sampling gas supply pipe for supplying a part of the exhausted gas to the gas analysis unit, and a porous gas filter disposed in the vicinity of a base end of the porous filter in the negative pressure chamber toward the internal space of the porous filter, An exhaust gas analyzer comprising an adhering substance removing means for removing the adhering substance adhering to the filter,
The deposit removing means includes a fluid ejection nozzle that ejects fluid toward the porous filter, and the nozzle is provided with a cylindrical fluid guide portion at the tip of a Laval nozzle portion. A sampling apparatus for exhaust gas analysis, characterized in that an elongated opening is formed in the part in the fluid flow direction. A heat-resistant porous filter that protrudes from the furnace or flue and samples the exhaust gas in the furnace or flue, a negative pressure chamber into which the exhaust gas sampled by the porous filter is introduced, and sampling by the porous filter A sampling gas supply pipe for supplying a part of the exhausted gas to the gas analysis unit, and a porous gas filter disposed in the vicinity of a base end of the porous filter in the negative pressure chamber toward the internal space of the porous filter, An exhaust gas analyzer comprising an adhering substance removing means for removing the adhering substance adhering to the filter,
A sampling apparatus for exhaust gas analysis, wherein the deposit removing means includes a shock wave generating electrode that receives a pulse voltage and generates a shock wave toward the porous filter. Said pressure detecting means for detecting the internal pressure of the negative pressure chamber is provided, wherein the deposit removing means, operating state when the negative pressure of the negative pressure chamber is detected to have increased above a predetermined value by the pressure detecting means The sampling apparatus for exhaust gas analysis according to claim 1 or 2, wherein the sampling apparatus is inactivated when the negative pressure is less than a predetermined value.   The sampling for exhaust gas analysis according to claim 3, further comprising: a communication path that connects the negative pressure chamber and the furnace or the flue; and an eject air injection means that injects eject air into the furnace or the flue through the communication path. apparatus.

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