JP2015127685A - Gas component concentration distribution measurement device and exhaust gas denitrification system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas component concentration distribution measurement device and an exhaust gas denitrification system capable of efficiently performing denitrification.SOLUTION: The gas component concentration distribution measurement device includes: a crank shaped support member 22 which has a crank part 21 of a U-like shape, which is disposed in a direction perpendicular to a flow direction of flue gas in a flue 103; a light transmitting tube 12 which allows a laser beam to transmit therethrough, and which is formed integrally with the crank part 21; a measurement zone L in which a part of the light transmitting tube 12 is segmented being separated by a predetermined distance and is exposed to a measuring area; a laser emission part that emits a laser beam into the light transmitting tube 12; a laser reception part that receives the laser beam passing through the measurement zone L to detect the light intensity of the laser beam out of the light transmitting tube 12; and a rotary part 23 that rotates on the axis of the crank shaped support member 22. By rotating the rotary part 23, the light transmitting tube 12 disposed in the crank part 21 rotates in an area separated away by a predetermined distance from the axis while absorbing the laser beam; thereby the gas component concentration in the exhaust gas is measured.

Description

  The present invention relates to a gas component concentration distribution measuring device and an exhaust gas denitration system.

  Conventionally, a laser gas analyzer is known as an apparatus for measuring the concentration of a specific substance contained in a gas mixture. This laser gas analyzer uses the characteristic that each gaseous gas molecule has a specific light absorption wavelength, irradiates a gas containing a specific substance with laser light, and determines the specific substance from the amount of absorption at that specific wavelength. Is a measure of the concentration.

  The following Patent Document 1 discloses a technique for sucking a gas from a piping unit through which a gas containing ammonia flows and guiding the sucked gas to a laser gas spectrometer to measure the concentration of ammonia contained in the gas. .

Patent Document 2 discloses a sampling pipe inserted into a flue to collect exhaust gas, a flow cell unit connected to the sampling pipe via a heating conduit, and a laser gas analyzer connected to the flow cell unit. An ammonia concentration measuring device is disclosed. In the ammonia concentration measuring device disclosed in Patent Document 2, an adsorbent that adsorbs sulfur trioxide (SO ₃ ) but allows ammonia to pass through the inside of the sampling tube is loaded, and the gas from which sulfur trioxide has been removed from the exhaust gas is added. By introducing it into a laser gas analyzer, the measurement accuracy of ammonia is improved.

JP 2012-8008 A JP 2010-236877 A

The sampling type concentration measuring devices disclosed in Patent Documents 1 and 2 have the following problems.
It is difficult to speed up the measurement when the gas is sucked and led to the measurement pipe.
Since the concentration measurement is performed after the gas is drawn into the measurement pipe, the gas flowing through the pipe and the state of the gas drawn into the measurement pipe (for example, moisture concentration, temperature, etc.) differ, resulting in measurement accuracy. Decreases.
Since the concentration is measured by collecting the circulating gas locally, the concentration distribution cannot be acquired even if the local gas concentration can be measured. Further, if concentration measurement is performed by sequentially changing sampling locations, it is possible to acquire a concentration distribution, but it is necessary to suck and discharge gas at each position, which is complicated and takes time.

  Therefore, for example, when denitrating nitrogen oxides in the exhaust gas of a boiler device, the appearance of an exhaust gas denitration system capable of accurately grasping the gas component concentration distribution and performing efficient denitration is desired.

  In view of the above problems, the present invention provides a gas component concentration distribution measuring apparatus and exhaust gas denitration capable of accurately grasping the gas component concentration distribution and performing efficient denitration when denitrating nitrogen oxides in the exhaust gas. The problem is to provide a system.

  A first invention of the present invention for solving the above-described problem is a flue through which combustion exhaust gas passes, and a U-shaped crank installed in a direction orthogonal to the gas flow direction of the combustion exhaust gas in the flue. A crank-shaped support body having a portion, a light-transmitting tube that is provided integrally with the crank portion, and that passes a laser beam, and a part of the light-transmitting tube is separated by a predetermined distance and exposed to the measurement field of the flue A measurement region, a laser emitting unit for emitting the laser light from the outside of the flue into the light transmission tube, and the laser light that has passed through the measurement region are received outside the flue, and the laser A laser receiving unit for detecting the light intensity of the light, and a rotating unit that rotates about the shaft of the crank-shaped support, and the rotation is performed when measuring the gas component concentration of the combustion exhaust gas. By rotating the part, the light transmission tube provided in the crank part is A gas component characterized by measuring the concentration of the gas composition in the combustion exhaust gas in a measurement region having a predetermined interval at each rotation position by rotating a region away from the recording shaft portion by absorption of a laser beam. It is in the concentration distribution measuring device.

  A second invention is the gas component concentration distribution measuring apparatus according to the first invention, wherein the measurement region is different along the longitudinal direction of the light transmission tube and is located in a part of the partitioned region. It is in.

  According to a third invention, in the first or second invention, the laser light emitting unit and the laser light receiving unit are installed on the same side of one side of the flue, and the light transmission tube is provided from the laser light emitting unit. A first light-transmitting tube that transmits laser light, a reflecting portion that reflects laser light on an end side in the laser traveling direction on the first light-transmitting tube side, and a laser beam reflected by the reflecting portion. A gas component concentration distribution measuring apparatus comprising: a second light transmission cylinder having a measurement region that is light-transmitted and a part of which is separated by a predetermined distance and exposed to the measurement field of the flue. .

  A fourth invention is a denitration apparatus comprising a reducing agent supply means for supplying a reducing agent into combustion exhaust gas, and a partitioned denitration catalyst for denitrating nitrogen oxide (NOx) in the exhaust gas containing the reducing agent. And the gas component concentration distribution measuring device according to any one of the first to third aspects of the present invention, which is provided on at least one of the inlet side and the outlet side of the denitration device and measures the gas component concentration distribution in the exhaust gas. In the exhaust gas denitration system, the gas component concentration distribution is obtained from the measurement result of the gas component concentration distribution measuring device.

A fifth invention is the exhaust gas denitration system according to the fourth invention, wherein the gas component is either one or both of ammonia (NH ₃ ) and nitrogen oxide (NOx).

  According to the present invention, it is possible to omit the installation of a plurality of laser light emitting units by providing a single laser light emitting unit and measuring the laser light emitted from the laser light receiving units, thereby simplifying the laser measuring device. Can be achieved.

FIG. 1 is a schematic view of a boiler apparatus provided with a denitration apparatus according to the present embodiment. FIG. 2 is a schematic perspective view showing the overall configuration of the gas component concentration distribution measuring apparatus installed in the denitration apparatus. FIG. 3 is a schematic side view of the probe means of FIG. FIG. 4 is a schematic diagram of a gas component concentration distribution measuring apparatus according to the second embodiment. FIG. 5 is an enlarged view of the reflecting portion. FIG. 6 is a schematic cross-sectional view of the light transmission tube. FIG. 7 is a schematic view showing a state of rotation of the light transmission tube arranged in the flue. FIG. 8 is a schematic diagram of a gas component concentration distribution measuring apparatus according to the third embodiment. FIG. 9 is a schematic view showing a state of rotation of the light transmission tube arranged in the flue. FIG. 10 is a conceptual diagram of absorption spectroscopy measurement. FIG. 11 is an absorption chart of absorption spectroscopy measurement. FIG. 12 is a diagram showing the relationship between the dust concentration in the exhaust gas and the laser light transmittance. FIG. 13 is a system diagram showing a schematic configuration example of an ammonia injection device of the denitration device according to the present embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by this Example, Moreover, when there exists multiple Example, what comprises combining each Example is also included.

FIG. 1 is a schematic view of a boiler apparatus provided with a denitration apparatus according to the present embodiment.
As shown in FIG. 1, a boiler apparatus 100 equipped with an exhaust gas denitration system according to this embodiment supplies a reducing agent (for example, ammonia: NH ₃ ) into combustion exhaust gas (hereinafter referred to as “exhaust gas”) 102 from a boiler 101. A denitration apparatus 105 having a denitration catalyst 106 for denitrating nitrogen oxide (NOx) containing a reducing agent, and an outlet side of the denitration apparatus 105. A gas component for measuring the ammonia concentration by laser measuring means for the gas component (NH ₃ , NOx) concentration distribution in the exhaust gas 102 in a region corresponding to the denitration catalyst 106 that is provided and orthogonal to the gas flow of the denitration device 105. A measurement result of ammonia concentration of the gas component concentration distribution measuring apparatus 10A (10B, 10C). Ri, and requests the concentration distribution of ammonia sectioned areas. In FIG. 1, reference numeral 107 denotes an air preheater, and 108 denotes a chimney.

  Further, in this embodiment, the control device 20 for obtaining a section with insufficient denitration based on the obtained ammonia concentration distribution, and an adjusting means for adjusting the reducing agent supply amount from the reducing agent supply means corresponding to the section with insufficient denitration. The opening degree setting part 109 which is is provided.

  FIG. 2 is a schematic perspective view showing the overall configuration of the gas component concentration distribution measuring apparatus installed in the denitration apparatus, and FIG. 3 is a schematic side view of the probe means of FIG. As shown in FIGS. 2 and 3, the gas component concentration distribution measuring apparatus 10 </ b> A is installed in a direction perpendicular to the flue 103 through which the exhaust gas 102 passes and the gas flow direction of the combustion exhaust gas 102 in the flue 103. A crank-shaped support body 22 having a crank-shaped crank portion 21, a light-transmitting tube 12 that is provided integrally with the crank portion 21 and passes the laser beam 11, and a part of the light-transmitting tube 12 is separated by a predetermined distance, and smoke The measurement region L exposed to the measurement field on the road 103, the laser light emitting unit 13 for emitting the laser light 11 from the outside of the flue 103 into the light transmission tube 12, and the laser light 11 passing through the measurement region L are smoked. It comprises a laser light receiving portion 14 that receives light outside the road 103 and detects the light intensity of the laser light 11, and a rotating portion 23 that rotates around the shaft portion of the crank-shaped support 22. Gas component concentration When measuring, the rotation region 23 causes the light transmission cylinder 12 provided in the crank portion 21 to rotate in a region away from the shaft portion by a predetermined distance, so that a measurement region L having a predetermined interval at each rotation point is measured. The gas composition (ammonia) concentration in the exhaust gas 102 is measured by absorption of the laser beam 11.

  In the present embodiment, the light transmission tube 12 having a region L separated by a predetermined distance is rotated around the shaft portion rotated by the rotating portion 23 and the crank portion 22 separated from the shaft portion by a predetermined distance is rotated. By rotating, the concentration of the gas composition of the exhaust gas 102 can be measured.

As shown in FIG. 3, the laser light 11 from the laser light emitting unit 13 is transmitted through the light transmission tube 12, passes through the measurement region L at a predetermined interval from the laser light emitting end 12a, and then passes through the laser light receiving end 12b. The light is introduced into the light transmission tube 12 and measured by the laser light receiving unit 14. In the figure, reference numeral 16 denotes a reflection mirror.
Note that the laser light emitting unit 13, the laser light receiving unit 14, and the rotating unit 23 are each connected by an optical fiber 17.

FIG. 2 shows a case where the flue 103 has a rectangular shape composed of a long direction and a short direction, and a plurality of (three in this embodiment) probes are installed.
In this case, the measurement region L may be positioned along a part of the partitioned region so as to be different along the longitudinal direction of the light transmission tube 12.
That is, in the light transmission tube 12 on the left side in the drawing, the measurement region L ₁ is formed on the front side in the drawing, and in the light transmission tube 12 in the middle in the drawing, the measurement region L ₂ is formed on the center side in the drawing, in the right side of the light transmitting tube 12 in the figure, in the figure, the back side to form a measurement area L _3, that each rotate, it is possible to measure a plurality of regions.

  As a result, conventionally, when measuring the concentration distribution at a plurality of locations, a laser beam transmitter and a light receiver are individually provided for each laser beam 11 in the light transmission tube, and measurement is performed individually. However, although a plurality of sets of light transmitters and a plurality of sets of light receivers are required, according to the present invention, since only one laser light emitting unit 13 and laser light receiving unit 14 need be provided, the laser device can be simplified. Can be achieved.

Next, the principle of concentration distribution measurement according to the present embodiment will be described with reference to the drawings.
FIG. 10 is a conceptual diagram of absorption spectroscopy measurement. FIG. 11 is an absorption chart of absorption spectroscopy measurement.
The Lambert-Beer law is known as a relational expression indicating the relationship between the light intensity of the laser beam and the concentration of the measurement object.

As shown in FIG. 10, the Lambert-Beer law is a measurement of the distance of the laser path between the light transmitting point (laser light emitting end 12a) and the light receiving point (laser light receiving end 12b) of the laser beam 11. When the region is L, the irradiation intensity of the laser beam 11 is I ₀ , the received light intensity of the laser beam 11 is I (L), and the concentration of the measurement target (ammonia) existing in the distance L is C ₀ , the following ( 1) The relationship of the formula is established.
I (L) = I ₀ exp (−kC ₀ L) (1)
Here, k is a proportionality coefficient set according to the absorbance of the measurement target.

Assuming that the density average value of the divided area for measuring the density of the measurement object is C ₁ and the distance of the laser path in the divided area (measurement area L where the light transmission tube is divided) is L ₁ , the above equation (1) Can be expressed as the following equation (2).
I (L) = I ₀ exp (−kC ₁ L ₁ ) (2)

When irradiating the laser beam 11 for each preset laser path, the distance of the laser path in the divided region (measurement region that is a place where the light transmission tube is divided) L, the irradiation intensity I ₀ of the laser beam 11 and the laser beam received light intensity I of, since it is known, by the above equation (2) can be calculated the density average value C ₁ of the divided regions is unknown.

  And in gas component concentration distribution measuring apparatus 10A provided with the said structure, the concentration distribution of ammonia of a concentration measurement area | region is acquired with the following procedures.

Further, since the exhaust gas 102 from the boiler 101 contains soot and dust, when the optical path length of the laser light 11 that is the measurement region L is increased, the light transmittance is attenuated due to the effect of soot and dust.
FIG. 12 is a diagram showing the relationship between the dust concentration in the exhaust gas and the laser light transmittance.
In FIG. 12, when the wavelength is 1.5 μm, it is confirmed that measurement is possible with an optical path length of 2.0 m in coal ash having a dust concentration of about 6 g / Nm ³ .
Therefore, when the dust concentration is higher than that, it is preferable to measure with an optical path length of 1.5 m, more preferably around 1 m.

Here, in order to measure the ammonia (NH ₃ ) concentration in the exhaust gas as in this embodiment, a semiconductor laser (semiconductor element: InGaAs can be exemplified. Wavelength: 1.5 μm, output: about 1 mW Can be exemplified).

FIG. 13 is a system diagram showing a schematic configuration example of an ammonia injection device of the denitration device according to the present embodiment.
As shown in FIG. 13, the ammonia injection device 104 includes a total flow control valve 32 in the ammonia main system 31 of the flow path pipe connected to the ammonia supply source. The ammonia main system 22 includes a plurality of (six in the illustrated example) ammonia supply systems 26 branched from the header 24 downstream of the total flow control valve 23.

  Further, as shown in FIG. 13, the ammonia supply system 26 includes a flow control source valve 25 and a plurality of (three in the illustrated example) injection nozzles 27, and is a flow path through which the exhaust gas 102 flows. The injection nozzles 27 are installed inside the flue 103 so as to have a grid-like arrangement. The injection nozzle 27 causes the ammonia supplied from the ammonia supply source through the ammonia main system 22, the header 24, and the ammonia supply system 26 of the flow path piping to flow out into the flue 103 in the form of droplets or gas, and burns Ammonia as a reducing agent is injected into the exhaust gas. In addition, ammonia injected in the form of droplets absorbs heat from high-temperature combustion exhaust gas and is gasified.

  The ammonia gas thus injected into the flue 103 is stirred and mixed with the combustion exhaust gas 102 by passing through the mixer. As a result, ammonia reacts with the nitrogen oxides and passes through the denitration catalyst 106 in the denitration device 105, so that the nitrogen oxides are removed from the combustion exhaust gas by being decomposed into water and nitrogen.

A measured value of the ammonia (NH ₃ ) concentration measured by the gas component concentration distribution measuring device 10 A is input to the opening setting unit 109 via the control device 20. Upon receiving such an ammonia concentration input, the opening setting unit 109 sets the opening (opening control) of the total flow control valve 23 based on the average value of the ammonia concentration, and adjusts the ammonia concentration at a plurality of locations. Based on this, the opening of each flow control source valve 25 is set (opening control). That is, the opening setting unit 109 outputs the opening control signals of the total flow control valve 23 and the flow control source valve 25.

  In this case, the opening degree control of the flow control source valve 25 by the opening degree setting unit 109 is performed based on a control map that defines a correlation between a predetermined ammonia concentration and an opening degree for each flow control source valve 25. In other words, the denitration device 105 is produced by obtaining the correlation data in advance through experiments or the like because various conditions (the channel system of the flue 103, the channel cross-sectional area, the type of fuel, etc.) differ for each boiler 101. The control map is stored in the opening setting unit 109. In this control map, the opening degree of the flow control source valve 25 that differs for each of the plurality of ammonia supply systems 26 with respect to the ammonia concentration at a plurality of positions measured in the section of the ammonia concentration in the flue 103. Are set individually.

  As described above, the gas component concentration distribution measuring apparatus 10A creates an ammonia concentration distribution in the concentration measurement region in the flue 103 on the outlet side of the denitration catalyst 106, and outputs the ammonia concentration distribution to the opening setting unit 109. .

  According to such a denitration device 105, the ammonia concentration distribution on the outlet side of the denitration catalyst 106 in the flue 103 is detected by the gas component concentration distribution measurement device 10 </ b> A, and the detection result is output to the opening setting unit 109. . In the opening setting unit 109, the opening control of the total flow control valve 23 is performed based on the average value of the ammonia concentration, and the flow control source is based on the ammonia concentration distribution obtained by the gas component concentration distribution measuring apparatus 10A. The opening degree control of the valve 25 is performed. Thereby, the ammonia injection amount distributed to each of the plurality of ammonia supply systems 26 can be automatically adjusted according to the measured value of the ammonia concentration having a short time constant while continuing the operation of the denitration apparatus 105.

  At this time, since the opening degree control of the flow control source valve 25 is performed based on a map of a predetermined ammonia concentration and the opening degree of each flow control source valve 25, the ammonia whose total supply amount is defined by the ammonia concentration. The ammonia distribution amount for the ammonia supply system 26 is adjusted according to the opening degree of the flow control source valve 25.

  Thus, since the ammonia concentration distribution is related to the performance deterioration of the denitration catalyst 106, if the ammonia injection amount distribution control by the ammonia injection device 104 is performed based on the ammonia concentration distribution, the downstream side of the denitration device 105. It is possible to control the distribution of leaked ammonia discharged excessively. In addition, since leaked ammonia is a cause of blocking the air preheater 107, if the distribution control of the ammonia injection amount by the ammonia injection device 104 is performed based on the concentration detection, it contributes to the reduction of the blocking frequency of the air preheater 107. It becomes possible.

  According to the denitration apparatus 105 according to the present embodiment, the reducing agent injection amount distributed to a plurality of reducing agent supply systems according to the measured value of the ammonia concentration with a short time constant while continuing the operation of the denitration apparatus 105. Can be automatically adjusted. As a result, it is possible to extend the life of the denitration catalyst 106 and optimize the renewal of the denitration catalyst 106 by optimizing the distribution of reducing agent injection. As a result, in the denitration apparatus 105, it is possible to realize cost reduction and optimization of ammonia consumption accompanying the renewal of the denitration catalyst 106.

  In this embodiment, the gas component concentration distribution measuring device 10A (10B, 10C) is installed on the outlet side of the denitration device 105 and the ammonia concentration is measured, but the gas is supplied to the inlet side and the outlet side of the denitration device 105. Component concentration distribution measuring devices A (10B, 10C) and A (10B, 10C) are provided, and by measuring the ammonia concentration supplied to the denitration catalyst 106 and the leaked ammonia concentration after denitration, the leakage ammonia concentration relative to the supplied ammonia concentration The distribution can also be measured.

  Further, in this embodiment, the ammonia concentration is measured on the outlet side of the denitration device 105, but is not limited to the measurement of the gas component on the outlet side of the denitration device 105, and the flue from the boiler outlet to the denitration device 105 is measured. In any of 103, the gas component on the inlet side may be designed.

  In the present embodiment, as shown in FIG. 1, a control device 20 for controlling the semiconductor laser is installed. The control device 20 is, for example, a computer and includes a CPU, a ROM (Read Only Memory) for storing a program executed by the CPU, a RAM (Random Access Memory) functioning as a work area when each program is executed, A hard disk drive (HDD) as a capacity storage device, a communication interface for connecting to a communication network, an access unit to which an external storage device is mounted, and the like are provided. These units are connected via a bus. Furthermore, the control device 20 may be connected to an input unit such as a keyboard and a mouse and a display unit including a liquid crystal display device that displays data.

  The storage medium for storing the program executed by the CPU is not limited to the ROM. For example, other auxiliary storage devices such as a magnetic disk, a magneto-optical disk, and a semiconductor memory may be used. In the present embodiment, the control device 20 is realized by a single computer, but may be realized by a plurality of computers.

  First, the laser light emitting unit 13 of the semiconductor laser is activated by the control device 20 so as to correspond to the laser path to be measured, and further, the measurement in the laser path is performed after the output of the laser light is stabilized.

  After the measurement in this laser path is completed, the measurement in the next laser path is started. In this way, measurement for each laser path is sequentially performed. Thereafter, laser light is emitted from the laser light emitting unit 13, and the laser light absorbed by the measurement target as the laser light passes through a predetermined laser path is received by the laser light receiving unit 14.

The laser light receiver 14 detects the light intensity from the received light. The detected value of the laser beam is output to the control device 20. At this time, the control device 20 can associate the detection value by the laser light receiving unit 14 with the identification information (P _{1 to} P ₈ ) of the laser path corresponding to the detection value.

  The detection value and the laser path information input to the control device 20 are stored in the control device 20 in association with each other. Furthermore, the control device 20 also stores the irradiation intensity of the laser light from the laser emitting unit 13 during the laser irradiation. Then, the control device 20 creates a NO concentration distribution based on the stored data.

Specifically, the distance between the divided areas on each laser path, the input detection value, and the irradiation intensity of the laser light are read out, and the divided areas are obtained by using the density calculation formula represented by the above expression (2). The concentration of each measurement target is calculated. Then, the density distribution of the density measurement area is created by interpolating the density of each divided area. Thereby, the concentration distribution of the measurement object in the concentration measurement region is obtained.
The density distribution of the density measurement region thus obtained is presented to the user, for example, by being displayed on a display device (not shown) connected to the control device 20.

  And if all the ammonia concentration distribution which leaks is below a predetermined value, a driving | running will be continued on the conditions as it is. In this case, the injection amount of the ammonia injection device 104 is not adjusted.

  On the other hand, when there is a place where the concentration is high in a part of the ammonia concentration distribution, when the determination unit of the control device 20 determines, the information signal is sent to the opening setting unit 109. Then, in the opening setting unit 109, the opening control of the flow control source valve 25 is performed so that ammonia from the ammonia injection device 104 corresponding to the identified high ammonia concentration distribution can be injected. Thereby, the ammonia injection amount distributed to each of the plurality of ammonia supply systems 26 can be automatically adjusted according to the measured value of the ammonia concentration while continuing the operation of the denitration apparatus 105.

  As a result, by measuring each ammonia concentration distribution by the gas component concentration distribution measuring device 10A on the outlet side of the denitration device 105, it can be confirmed whether the denitration is uniformly performed in real time.

Nitrogen oxide (NOx) fluctuations in the exhaust gas occur when the boiler is started up, when the boiler load fluctuations or the type of fuel supplied to the boiler 101 is changed.
Therefore, using this device, when there is a load change, etc., it is determined whether nitrogen oxide is denitrated reliably by measuring the concentration distribution more frequently than the normal number of measurements. You may do it.

FIG. 4 is a schematic diagram of a gas component concentration distribution measuring apparatus according to the second embodiment. FIG. 5 is an enlarged view of the reflecting portion. In addition, about the member which overlaps with the member of Example 1, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.
In the above-described embodiment, the laser light emitting unit 13 and the laser light receiving unit 14 are respectively installed on the left and right sides of the flue. In this embodiment, the laser light emitting unit 13 and the laser light receiving unit 14 are connected to the flue 103. It is installed on the same side of one side (right side in this example), and the laser light receiving / emitting unit 15 is used.

  In this embodiment, the light transmission tube 12 is divided into the first light transmission tube 12A for transmitting the laser light 11 and the laser light 11 on the end side in the laser traveling direction on the first light transmission tube 12A side. A second reflecting portion 18 having a measurement region L that is reflected by the reflecting portion 18 and a laser beam 11 reflected by the reflecting portion 18 is partially separated by a predetermined distance and exposed to the measurement field of the flue 103. And a light transmission tube 12B.

FIG. 6 is a schematic cross-sectional view of the light transmission tube. FIG. 7 is a schematic view showing the state of rotation of the light transmission tube arranged in the flue.
FIG. 6 shows a configuration of the first light transmission tube 12A and a second light transmission tube 12B having an opening 12c that is a measurement region L of a predetermined distance provided integrally with the first light transmission tube 12A. . FIG. 7 shows a state in which the trajectory in the rotation of the first light transmission tube 12A and the second light transmission tube 12B is shown in the rectangular flue 103.
As shown in FIG. 7, the opening 12c of the second light transmission tube 12B is rotated by the rotation unit 23 so as to always face this axis centering on the axis of the rotation unit 23. Therefore, in order to prevent intrusion of dust or the like in the exhaust gas 102 from the opening 12c, it is preferable that this rotation is rotated at an angle of 15 degrees to 165 degrees from the horizontal direction.

FIG. 8 is a schematic diagram of a gas component concentration distribution measuring apparatus according to the third embodiment. FIG. 9 is a schematic view showing a state of rotation of the light transmission tube arranged in the flue. In addition, about the member which overlaps with the member of Example 1 and 2, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.
In the above-described embodiment, the opening 12c always faces the axis, but in this embodiment, the opening 12c is always positioned below (downward in the vertical axis direction).

  As shown in FIG. 8, in this embodiment, a pair of opposed annular parts 31, 31, a triangle support part 32 including three sides 32 a to 32 c that are rotatable in the annular part 31, and a triangle A first light transmission tube 12A that is supported by one side 32a of the support unit 32 and passes the laser light 11, and a reflection unit that reflects the laser light 11 on the end side in the laser traveling direction on the first light transmission tube 12A side. (Not shown) and the laser beam 11 that is integrally supported by the first light transmission cylinder 12A and reflected by the reflecting portion are transmitted, and a part of the lower surface side thereof is separated by a predetermined distance, and the flue 103 And a second light transmission tube 12B having a measurement region L exposed to the measurement field.

  Then, the laser light emitting unit 13 that emits the laser light 11 from the outside of the flue 103 into the first light transmission cylinder 12A and the laser light 11 that transmits the second light transmission cylinder 12B that has passed through the measurement region L A laser light receiving unit 14 that receives light outside the flue 103 and detects the light intensity of the laser light 11 is provided, but is omitted in FIG.

  Further, the annular portions 31, 31 are connected by three support rods 34a to 34c, and the annular portions 31, 31 connected by the connecting portions are supported by the crank portion 21 similar to that shown in FIG. The rotating portion that rotates around the shaft portion of the crank portion 21 rotates around the rotating portion with a predetermined distance.

  When measuring the gas component concentration of the flue gas 102, the rotation of the rotating part causes the light transmission cylinder 12 provided in the crank part 21 to rotate in a region away from the shaft part by a predetermined distance. The concentration of the gas composition in the combustion exhaust gas in the measurement region L having a predetermined interval at the location is measured by absorption of laser light.

  In the present embodiment, the triangle support portion 32 that is rotatable in the annular portions 31 and 31 is arbitrarily rotatable via the rotation portion 33, and a weight provided on the lower surface side of the second light transmission tube 12B. 35, the second light transmission tube 12B is always positioned on the lower side in the vertical axis direction.

  As a result, as shown in FIG. 9, the opening 12c of the second light transmission tube 12B is always located at the lower portion in the vertical axis direction, and is not affected by the dust in the exhaust gas 102.

10A to 10C Gas component concentration distribution measuring device 11 Laser light 12 Transmitting cylinder 12a Laser light emitting end 12b Laser light receiving end 13 Laser light emitting portion 14 Laser light receiving portion 21 Crank portion 22 Crank-like support body 100 Boiler device 101 Boiler 102 Combustion exhaust gas (Exhaust gas)
103 Flue 104 Ammonia injection device 105 Denitration device 106 Denitration catalyst

Claims (5)

The flue through which the flue gas passes,
A crank-shaped support body installed in a direction perpendicular to the gas flow direction of the flue gas of the flue, and having a U-shaped crank portion;
A light-transmitting tube provided integrally with the crank portion and passing a laser beam;
A measurement region in which a part of the light transmission tube is divided by a predetermined distance and exposed to the measurement field of the flue;
A laser light emitting section for emitting the laser light from the outside of the flue into the light transmission tube;
The laser beam that has passed through the measurement region is received outside the flue, and a laser receiving unit that detects the light intensity of the laser beam;
A rotating portion that rotates around the shaft portion of the crank-shaped support,
When measuring the gas component concentration of the combustion exhaust gas, the rotation of the rotating part causes the light transmission cylinder provided in the crank part to rotate in a region that is a predetermined distance away from the shaft part, so A gas component concentration distribution measuring apparatus for measuring a concentration of a gas composition in combustion exhaust gas in a measurement region having an interval by absorption of a laser beam. In claim 1,
The gas component concentration distribution measuring apparatus, wherein the measurement region is different along the longitudinal direction of the light transmission tube and is located in a part of the partitioned region. In claim 1 or 2,
The laser light emitting unit and the laser light receiving unit are installed on the same side of one side of the flue,
The light transmission tube is
A first light transmission tube for transmitting laser light from the laser light emitting unit;
A reflection part for reflecting the laser beam on the end side in the laser traveling direction on the first light transmission tube side;
A second light transmission tube having a measurement region that transmits the laser light reflected by the reflection unit and is partially separated by a predetermined distance and exposed to the measurement field of the flue. Gas component concentration distribution measuring device. Reducing agent supply means for supplying a reducing agent into the combustion exhaust gas;
A denitration apparatus including a denitration catalyst that denitrates nitrogen oxide (NOx) in the exhaust gas containing the reducing agent;
A gas component concentration distribution measuring device according to any one of claims 1 to 3, which is provided on at least one of an inlet side or an outlet side of the denitration device and measures a gas component concentration distribution in exhaust gas;
An exhaust gas denitration system, wherein a gas component concentration distribution is obtained from a measurement result of the gas component concentration distribution measuring device. In claim 4,
The exhaust gas denitration system, wherein the gas component is either one or both of ammonia (NH ₃ ) and nitrogen oxide (NOx).

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