JP4621966B2 - Gas bleeder - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gas extraction device that extracts exhaust gas from exhaust gas containing dust discharged from a combustion facility or the like.
[0002]
[Prior art]
Exhaust gas discharged from combustion facilities such as boilers and waste incinerators contains harmful components such as sulfur oxides and nitrogen oxides. In order to release these exhaust gases to the atmosphere, it is necessary to make them harmless with a flue gas treatment device such as a flue gas desulfurization device or a flue gas denitration device.
[0003]
A general combustion facility will be described with reference to the drawings. FIG. 4 is a conceptual diagram of a general combustion facility.
In the combustion facility 200, the fuel stored in the asphalt tank 201 is heated by the heater 202 and burned by the boiler 203. The burned gas is mixed with dust derived from fuel. The dust-mixed gas is absorbed by the absorption tower 207 through the gas duct 101, the denitration device 204, the preheater 205, and the dust collector 206, and is released from the chimney 208 to the atmosphere.
[0004]
For example, SO ₂ and SO ₃ are included in the gas passing through the gas duct 101.
In order to prevent SOx from condensing and corroding the gas duct 101, the gas temperature is maintained at a temperature above the acid dew point. Since the acid dew point decreases when the SO ₃ content decreases, the temperature of the duct of the flue gas treatment apparatus can be lowered. However, the conventional analyzer so could not be measured continuously SO _3, maintained the temperature of the duct by predicting the content of SO ₃ tolerate. Therefore, the temperature of the gas duct 101 has to be increased as compared with the case where the SO ₃ content can be accurately grasped.
Further, the treatment is performed by absorbing SO ₃ into ammonia. When the content of SO ₃ is reduced, the amount of ammonia can be reduced and the ammonia consumption can be reduced. However, the conventional analyzer so could not be measured continuously SO _3, was supplied to the processing apparatus ammonia in anticipation overlook content of SO _3.
[0005]
For this reason, the development of analyzers for sulfur oxides, nitrogen oxides and the like in exhaust gas discharged from combustion facilities and smoke treatment devices has been actively conducted.
One of these analyzers is a SO ₃ gas continuous analyzer. Conventional analysis methods could not measure SO ₃ gas continuously in real time.
Therefore, the applicant has developed a measuring device capable of continuously measuring SO ₃ . In Japanese Patent Application No. 374103, the applicant has a suction pipe for sucking exhaust gas from a flue and a discharge pipe for discharging exhaust gas into the flue, and a cavity having two transparent windows facing each other. A light source for irradiating light into the cavity, a reflection mirror disposed outside the cavity, and for reciprocating the light from the light source into the upper air cavity a plurality of times, and the wavelength of the light after the reciprocation The invention of an SO ₃ concentration meter comprising a calculating means for calculating the SO ₃ concentration in the exhaust gas by spectroscopic analysis of light of 200 nm to 260 nm was filed.
[0006]
With the above configuration, the SO ₃ concentration in the exhaust gas can be measured by reciprocating the light from the light source a plurality of times into the cavity where the exhaust gas is sucked from the flue and performing spectral analysis of the light after the reciprocation.
At this time, a filter is provided in the middle of the suction pipe to remove gas dust. When the exhaust gas contains dust, dust entering the cavity is prevented from scattering light from the light source and causing measurement errors.
[0007]
If the above gas analyzer is used, it is possible to continuously analyze sulfur oxides and nitrogen oxides in the exhaust gas discharged from the combustion equipment and the flue gas treatment device, such as boilers and waste incinerators. The combustion facility can be operated appropriately.
For example, in the case of exhaust gas containing SO ₂ and SO ₃ at the same time, the component ratio of SO ₂ and SO ₃ can be measured continuously, the temperature of the acid dew point can be accurately grasped, and SO ₂ and SO 3 can be accurately measured. Corrosion of the duct can be prevented by appropriately controlling the temperature of the duct so as not to condense with ₃ .
Further, if the amount of SO ₃ is continuously measured, the amount of ammonia for the treatment of SO ₃ can be appropriately managed.
[0008]
[Problems to be solved by the invention]
By the way, dust having catalytic ability may be mixed in the exhaust gas.
In the case of a gas analyzer using a conventional filter, dust is captured by a filter of a gas bleeder that bleeds gas. Dust remains clogged in the filter. When the dust has catalytic ability for the component to be analyzed, the component of the gas that has passed through the filter changes. When the gas component changes, there is a problem that the measurement data of the gas analyzer is different from the gas component that actually passes through the gas duct.
For example, vanadium pentoxide is one of the main components of dust. Vanadium pentoxide has a catalytic ability to generate SO ₃ by reacting SO ₂ and O ₂ at a predetermined temperature. When vanadium pentoxide dust is trapped in the eyes of a filter provided in the middle of the suction pipe, when SO ₂ and SO ₃ mixed gas passes through the filter, a part of SO ₂ is O _2. since the reaction to become sO ₃ and the concentration of sO ₃ in the gas increases. The ratio of SO ₂ and SO ₃ which analyzed the gas analyzer becomes different from the true ratio of SO ₂ and SO ₃ in the gas flowing through the gas duct.
As in this example, if the measurement data of the gas analyzer cannot analyze the true gas component of the gas passing through the gas duct, it is possible to appropriately operate the combustion equipment such as the boiler and the garbage incinerator as described above. become unable.
[0009]
The present invention has been devised in view of the problems described above, and instead of the conventional gas extraction device, dust contained in the gas is continuously removed and dust having catalytic ability is mixed. However, an object of the present invention is to provide a gas extraction device that can extract gas without changing the gas component.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, a gas bleeder for extracting sample gas from a gas duct through which dust-mixed gas flows according to the present invention has a gas chamber having a gas inlet into which gas flows and a gas outlet from which gas flows out. A porous filter that removes dust from the gas and allows the sample gas to pass therethrough, a sample gas chamber having a sample gas outlet through which the sample gas flows out, and a vibration means that vibrates the porous filter, A porous filter partitions the gas chamber from the sample gas chamber ;
The vibration means has an upper expansion joint and a lower expansion joint that can freely expand and contract in the vertical direction .
[0011]
According to the configuration of the present invention, the gas mixed with dust flows into the gas chamber from the gas inlet and flows out from the gas outlet. Part of the gas in the gas chamber passes through the porous filter to remove dust, and moves to the sample gas chamber. The sample gas flows out from the sample gas outlet. Since the vibrating means vibrates the porous filter and shakes off the dust, the dust is not collected in the porous filter, and the gas component is not changed even if the dust has catalytic ability.
[0012]
Further, in the gas bleeder according to the present invention, the surface of the porous filter is parallel to the flow direction of the gas flowing in the gas chamber.
According to the configuration of the present invention, the surface of the porous filter is parallel to the gas flow direction, and the dust in the gas hardly collides with the surface of the porous filter. Therefore, the surface of the porous filter hardly captures the dust.
[0013]
In the gas bleeder according to the present invention, the gas flowing in the gas chamber further flows from top to bottom.
With the configuration of the present invention, the gas flows from the top to the bottom of the gas chamber, and the dust contained in the gas falls on the gravity, so that the surface of the porous filter is more difficult to capture the dust.
[0014]
Furthermore, the gas bleeder according to the present invention includes a gas inflow pipe and a gas outflow pipe that are arranged coaxially with the end portions facing each other, and the gas inflow pipe forms the gas inflow port. The gas outflow pipe forms the gas outlet, and the sample gas chamber communicates with an airtight sample gas container in which the gas inflow pipe and the gas outflow pipe communicate with each other, and an outer wall of the sample gas container. A pipe, the sample gas outlet pipe forms the sample gas outlet, the porous filter is a cylindrical filter, and one end of the cylindrical filter communicates with the gas inlet pipe, and the cylindrical filter It was assumed that the other end communicated with the gas outflow pipe.
According to the configuration of the present invention, gas flows in from the gas inflow pipe, passes through the inside of the porous filter cylinder, and flows out from the gas outflow pipe, and a part of the gas is removed from the dust by the porous filter. Since the sample gas enters the gas container and flows out from the sample gas outflow pipe, the structure is simple, the dust is difficult to accumulate, and the gas component is not changed even if the dust has catalytic ability.
[0015]
Furthermore, the gas bleeder according to the present invention includes a voltage-driven vibrator in which the vibration means is fixed to the porous filter.
With the configuration of the present invention, the voltage-driven vibrator directly vibrates the porous filter, so that dust trapped in the porous filter is shaken off from the porous filter, and the dust has catalytic ability. Do not change the gas component.
[0016]
Furthermore, in the gas bleeder according to the present invention, the vibration means has a mechanical vibrator fixed to the wall forming the sample gas chamber or the gas chamber.
With the above-described configuration of the present invention, the mechanical vibrator directly vibrates the sample gas chamber or the gas chamber, so that dust accumulated in the sample gas chamber or the gas chamber can flow out on the gas flow. The gas component is not changed even if the dust has catalytic ability.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred first embodiment of the present invention will be described with reference to the drawings. In each figure, common portions are denoted by the same reference numerals, and redundant description is omitted.
[0018]
The structure of the gas analyzer with a gas bleeder according to the first embodiment of the present invention will be described. FIG. 1 is a conceptual diagram of a first embodiment of the present invention. FIG. 3 is a conceptual diagram of a gas analyzer provided with the gas bleeder of the first embodiment of the present invention.
[0019]
First, the structure of the gas analyzer will be briefly described. The gas analyzer 100 includes a gas extraction device 102, a preheating temperature controller 104, a preheater 105, a cavity 106, a circulation pump 107, a light source 108, a reflection mirror 109, a spectroscope 110, a light detection element 111, a calculator 112, and a heater. 113 and a temperature controller 114.
[0020]
The gas bleeder 102 is a device that bleeds the gas 1 containing dust flowing through the gas duct 101, removes the dust from the bleed gas 2, and sends the sampling gas 4 to the preheater 105. The preheater 105 is a device that is controlled by the preheat controller 104 and preheats the sampling gas 4 to a temperature necessary for measurement, and sends the preheated gas to the cavity 106. The cavity 106 is a room for sealing a gas having a predetermined temperature, and has two transparent windows facing each other. The circulation pump 107 allows the extracted sampling gas to continuously pass through the cavity 106. The light source 108 is for irradiating light of a desired frequency into the cavity 106. The reflection mirror 109 is a mirror for reciprocating light from the light source 108 a plurality of times in the cavity 106, and is provided facing the transparent window. The spectroscope 110 is a device that splits incident light. The light detection element 111 is an element that converts the dispersed light into an electric signal, and is provided inside the spectrometer 110. The calculator 112 is a device that calculates the concentration of the gas component (for example, the concentration of SO ₃ ) based on the electrical signal output from the light detection element 111. The heater 113 is a device that is controlled by the temperature controller 114 and maintains the gas temperature in the cavity 106 at a desired temperature.
[0021]
Next, the operation of the gas analyzer will be briefly described. The gas 1 containing dust flows through the gas duct 101. The gas 1 is extracted by the gas extraction device 102 and becomes the sample gas 4 from which dust is removed. The sample gas 4 is preheated to a predetermined temperature by the preheater 105 and enters the cavity 106. The light from the light source 108 passes through the cavity 106 and is split by the spectroscope 110. The split light is converted into an electric signal by the light detection element 111. The calculator 112 calculates a gas component from the electrical signal. The sample gas 4 is returned to the gas duct 101 by the circulation pump 107.
[0022]
Next, the gas bleeder according to the first embodiment will be described in detail.
The gas extraction device 102 includes a gas chamber 10, a sample gas chamber 20, a porous filter 30, a vibration means 40, a gas duct 60, and an extraction pump 70.
The gas chamber 10 is a room through which gas containing dust extracted from the gas duct passes, and has a gas inlet 11 and a gas outlet 12. The gas inlet 11 is formed by a gas inflow pipe 13. The gas outlet 12 is formed by a gas outlet pipe 14. The gas inflow pipe 13 is a pipe for flowing gas into the gas chamber, and is a circular pipe having a predetermined diameter D. The gas outflow pipe 14 is a pipe through which gas flows out from the gas chamber, and is a circular pipe having a predetermined diameter D. The axes of the gas inflow pipe 13 and the gas outflow pipe 14 coincide with each other, and the axes are upright. The lower end of the gas inflow pipe 13 and the upper end of the gas outflow pipe 14 face each other with a predetermined distance.
[0023]
The porous filter 30 is a filter that removes the dust 5 in the gas and allows only the sample gas 4 to pass therethrough. The porous filter 30 is preferably a porous plate made of a material (for example, stainless steel or glass) that has a predetermined strength at high temperatures, has corrosion resistance, and does not have catalytic ability. The porous filter 30 is a circular tube having the same cross section as the gas inflow pipe 13 and the gas outflow pipe 14. The upper end of the circular pipe is connected to the lower end of the gas inflow pipe 13. The lower end of the circular pipe is connected to the upper end of the gas outflow pipe 14.
[0024]
The sample gas chamber 20 is a chamber through which the sample gas 4 that has passed through the porous filter 30 passes, and has a sample gas outlet 21. The sample gas chamber 20 is a space surrounded by the upper flange 22a, the cylinder 22b, and the lower flange 22c. The upper flange 22 a is an annular plate, and the inner hole is fixed to the outer periphery of the gas inflow pipe 13. The lower flange 22 c is an annular plate, and the inner hole is fixed to the outer periphery of the gas outflow pipe 14. The cylinder 22b is a cylindrical structure and has an upper end fixed to the outer periphery of the upper flange 22a and a lower end fixed to the outer periphery of the lower flange 22c. A sample gas outflow pipe 23 communicates with one place of the cylinder 22b.
[0025]
The vibration means 40 includes a voltage drive vibrator 41 and a drive device 42. The voltage drive vibrator 41 is, for example, a piezo element, and is fixed to the outer periphery of the porous filter 30.
The surface of the porous filter 30 is vibrated by repeating contraction and expansion due to a change in voltage of a predetermined frequency. The driving device 42 is an electric device that drives the voltage-driven vibrator 41 and applies a voltage fluctuation of a predetermined frequency to the voltage-driven vibrator 41.
[0026]
The gas duct 60 is a pipe for sucking gas containing dust from the gas duct and returning it to the gas duct via the gas chamber. The gas duct 60 includes an extraction duct 60a, a suction duct 60b, and a discharge duct 60c.
[0027]
The extraction pump 70 is a pump that extracts gas from the gas duct 101. The bleed duct 60 a communicates the gas duct 101 and the gas inflow pipe 13. A suction duct 60 b communicates the gas outlet pipe 14 and the suction port of the extraction pump 70. A discharge duct 60 c communicates the discharge port of the extraction pump 70 and the gas duct 101.
[0028]
The operation of the gas bleeder will be described below. The extraction pump 70 is activated, and the gas 1 including dust in the gas duct enters the gas inlet 11 via the extraction duct 60a. The gas 2 enters the gas chamber 20 from the gas inlet 11. Part of the gas 2 is dust removed by the porous filter 30, becomes the sampling gas 4, and enters the sampling gas chamber 20. The sampling gas 4 flows out from the sampling gas outlet and is sent to the gas analyzer. The dust removed by the porous filter 30 enters the suction port of the extraction pump 70 through the gas outlet 12 and the suction duct 60b together with the remaining gas. Driven by the drive device 42 of the vibration means 40, the voltage drive vibrator 41 vibrates and the porous filter 30 vibrates. The dust trapped in the porous filter 30 is separated from the porous filter 30 by the vibration, and further falls to the gas outlet 12 by gravity. The dust 5 and the gas 3 gather at the gas outlet 12, are pressurized by the extraction pump 70, and return to the gas duct 101.
[0029]
Next, the structure of the gas analyzer with a gas bleeder according to the second embodiment of the present invention will be described. Since the structure and operation other than the gas bleeder are the same, only different parts will be described. The gas bleeder according to the second embodiment of the present invention will be described in detail. FIG. 2 is a conceptual diagram of the first embodiment of the present invention.
[0030]
Since the parts other than the vibration device 50 are the same, only different parts will be described.
The vibration device 50 includes an upper expansion joint 51, a lower expansion joint 52, a mechanical vibration device 53, and a drive device 54.
The upper expansion joint 51 is an expansion joint that can freely expand and contract in the vertical direction, and is connected to the gas inflow pipe 13.
The lower expansion joint 52 is an expansion joint that can freely expand and contract in the vertical direction, and is connected to the gas outflow pipe 14.
The mechanical vibrator 53 is a device that mechanically vibrates the sample gas chamber, and is, for example, an eccentric rotor or an electromagnetic solenoid. The mechanical vibrator 53 vibrates the sample gas chamber up and down.
The drive device 54 is a device that drives the mechanical shaker 53.
[0031]
Since the operation of the gas bleeder of the second embodiment is the same as that of the first embodiment, a description thereof will be omitted.
[0032]
If the gas bleeder of the above-mentioned embodiment is used, the gas from which dust has been removed can be sent to the gas analyzer, and the gas analyzer can perform highly accurate gas analysis.
Moreover, since dust can be prevented from accumulating in the porous filter, even when the dust has a catalytic effect, the gas can be prevented from changing due to catalytic action, and the gas analyzer can perform highly accurate gas analysis. .
Moreover, it is possible to select the type of the vibrator and perform the vibration with the optimum vibration frequency and vibration mode, and the optimum vibration can be performed according to the physical properties of the dust trapped in the porous filter.
[0033]
The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the scope of the invention.
[0034]
【The invention's effect】
As described above, the gas extraction device for extracting the sample gas from the gas duct through which the dust-mixed gas of the present invention flows has the following effects due to its configuration.
Gas mixed with dust flows into the gas chamber from the gas inlet and flows out from the gas outlet. Part of the gas in the gas chamber passes through the porous filter to remove dust, and moves to the sample gas chamber. The sample gas flows out from the sample gas outlet. Since the vibrating means vibrates the porous filter and shakes off the dust, the dust is not collected in the porous filter, and the gas component is not changed even if the dust has catalytic ability.
In addition, since the surface of the porous filter is parallel to the gas flow direction and the dust in the gas rarely collides with the surface of the porous filter, the surface of the porous filter hardly captures the dust.
Further, the gas flowing in the gas chamber flows from the top to the bottom, and the dust contained in the gas falls on the gravity, so that the surface of the porous filter is more difficult to capture the dust.
In addition, gas flows in from the gas inflow pipe, passes through the inside of the porous filter cylinder, and flows out from the gas outflow pipe, and part of the gas is removed from the dust by the porous filter and enters the sample gas container. Since the sample gas flows out from the sample gas outflow pipe, the dust is not easily collected with a simple structure, and the gas component is not changed even if the dust has catalytic ability.
In addition, since the voltage-driven vibrator directly vibrates the porous filter, dust trapped in the porous filter is shaken off from the porous filter, and the gas component is changed even if the dust has catalytic ability. I won't let you.
Further, since the mechanical vibrator directly vibrates the sample gas chamber or the gas chamber, the dust accumulated in the sample gas chamber or the gas chamber can be put out on the gas flow and the dust can be discharged as a catalyst. Even if it has the capability, the gas component is not changed.
Therefore, it is possible to provide a gas bleeder that can continuously remove dust contained in gas and bleed gas without changing the gas component even when dust having catalytic ability is mixed.
[0035]
[Brief description of the drawings]
FIG. 1 is a conceptual diagram of a first embodiment of the present invention.
FIG. 2 is a conceptual diagram of a second embodiment of the present invention.
FIG. 3 is a conceptual diagram of a gas analyzer provided with an embodiment of the present invention.
FIG. 4 is a conceptual diagram of an example of combustion equipment.
[Explanation of symbols]
1 Gas 2 Gas 3 Gas 4 Sample Gas 5 Dust 10 Gas Chamber 11 Gas Inlet 12 Gas Outlet 13 Gas Inlet Pipe 14 Gas Outlet Pipe 20 Sample Gas Chamber 21 Sample Gas Outlet 22 Sample Gas Container 23 Sample Gas Outlet Pipe 30 Porous Quality filter 40 excitation means (first embodiment)
41 Voltage Driven Vibrator 42 Drive Device 50 Exciting Means (Second Embodiment)
51 Upper telescopic joint 52 Lower telescopic joint 53 Mechanical vibrator 54 Drive device 60 Gas duct 60a Extraction duct 60b Suction duct 60c Discharge duct 70 Extraction pump 100 Gas analysis device 101 Gas duct 102 Gas extraction device 103 Sample gas duct 104 Preheat controller 105 Preheater 106 Cavity 107 Circulating Pump 108 Light Source 109 Reflector Mirror 110 Spectroscope 111 Photodetector 112 Calculator 113 Heater 114 Temperature Controller 200 Combustion Device 201 Asphalt Tank 202 Heater 203 Boiler 204 Denitration Device 205 Preheater 206 Dust Collector 207 Absorption Tower 208 Chimney

Claims (6)

A gas extraction device for extracting a sample gas from a gas duct through which a gas mixed with dust flows, wherein a gas chamber having a gas inlet into which the gas flows in and a gas outlet through which the gas flows out, and removing dust from the gas A porous filter for allowing the sample gas to pass through, a sample gas chamber having a sample gas outlet through which the sample gas flows out, and an oscillating means for vibrating the porous filter, wherein the porous filter includes the gas chamber and the gas chamber. Partitions the sample gas chamber ,
The vibration extraction means has an upper expansion joint and a lower expansion joint that can freely expand and contract in the vertical direction.   The gas bleeder according to claim 1, wherein a surface of the porous filter is parallel to a flow direction of the gas flowing in the gas chamber.   The gas bleeder according to claim 1 or 2, wherein the gas flowing in the gas chamber flows from top to bottom.   The gas chamber has a gas inflow pipe and a gas outflow pipe that are arranged coaxially with the ends facing each other, the gas inflow pipe forms the gas inlet, and the gas outlet pipe connects the gas outlet. The sample gas chamber has an airtight sample gas container in which the gas inflow pipe and the gas outflow pipe communicate with each other, and a sample gas outflow pipe in communication with the outer wall of the sample gas container. Forms the sample gas outlet, the porous filter is a cylindrical filter, one end of the cylindrical filter communicates with the gas inflow pipe, and the other end of the cylindrical filter communicates with the gas outflow pipe The gas bleeder according to any one of claims 1 to 3, wherein   The gas bleeder according to any one of claims 1 to 4, wherein the exciting means includes a voltage-driven vibrator fixed to the porous filter.   6. The gas bleeder according to claim 1, wherein the vibration means includes a mechanical vibrator fixed to the sample gas chamber or a wall forming the gas chamber.

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