WO2020110934A1

WO2020110934A1 - Light-scattering-type dust concentration meter for cloudy exhaust gas

Info

Publication number: WO2020110934A1
Application number: PCT/JP2019/045778
Authority: WO
Inventors: 敏文田中
Original assignee: 株式会社田中電気研究所
Priority date: 2018-11-26
Filing date: 2019-11-22
Publication date: 2020-06-04
Also published as: JP2020085664A; FI20206375A1; CN112368564A

Abstract

Provided is a light-scattering-type dust concentration measurement device capable of, in a central area of a flue and over a long and sustained period, continuously and accurately measuring the dust concentration of cloudy exhaust gas including large amounts of mist. The present invention comprises: a dust concentration meter body A comprising a gasification device A1 that is disposed in a flue, takes in cloudy exhaust gas 2 to be measured, and gasifies mist and a dust detection device A2 that has a light emitter for emitting light onto an area where the mist has been gasified and a scattered light detector for detecting scattered light resulting from the reflection of the light by the dust; a dust concentration meter support B that is disposed so as to enter from the outside to the inside of the flue 1 and supports the dust concentration meter body A such that the same is disposed inside the flue 1; and a calculation/control device C for determining the concentration of the dust within the cloudy exhaust gas 2 on the basis of the scattered light intensity detected by the scattered light detector.

Description

Light scattering dust densitometer for cloudy exhaust gas

The present invention relates to a light scattering type dust densitometer, and in particular, mist (droplet particles) and dust (solid particles) are adsorbed and coexistent when the inside of the flue is below the dew point, and the dust in the cloudy exhaust gas The present invention relates to a light-scattering dust densitometer for cloudy exhaust gas capable of continuously, accurately and continuously measuring the concentration in a flue.

Exhaust gas generated at various factories contains harmful substances such as sulfur oxides and nitrogen oxides. For this reason, it is obligatory to install an exhaust gas treatment device such as a desulfurization device or a denitration device in a path (exhaust gas path) through which the exhaust gas is discharged into the atmosphere through the chimney.

On the other hand, there are also prescribed emission concentration regulations for dust. For example, in a paper mill or the like, the mist used in the exhaust gas treatment device is contained in the exhaust gas and becomes white smoke and is discharged from the chimney. In some cases, the local residents see white smoke emitted from the chimney and feel that dust above the regulation value is being emitted, and inquire to the factory.

Therefore, in various factories, a method to clearly show that white smoke is simply due to mist and does not contain dust that exceeds the regulation standard, that is, a method that can always be confirmed to comply with regulations related to dust emission. (Means) were strongly desired.

A light scattering type dust densitometer has been known as a means for measuring dust concentration. However, the conventional light-scattering dust concentration meter can continuously measure the dust concentration in the exhaust gas in real time, but for exhaust gas containing mist after processing with a desulfurization device (cloudy exhaust gas below the dew point) In principle, accurate dust concentration measurement is difficult due to the influence of a large amount of mist. That is, there has been a problem that the light scattering type dust densitometer cannot be applied to the measurement of the dust concentration of the exhaust gas containing the mist.

On the other hand, the inventor of the present application directly and continuously in the flue, for a long time continuously, in other words, for collecting a part of the cloudy exhaust gas in the flue to the inspection room outside the flue Invented a light scattering type dust densitometer capable of continuously and accurately measuring the duct concentration in the cloudy exhaust gas continuously and accurately for a long period of time without using a sampling tube. Patent Document 1, Patent Document 2, Patent Document The patent application shown in 3 has been filed and the patent right has already been acquired.

The light scattering type dust densitometer described in Patent Document 1 is a dust densitometer for measuring the dust concentration in a cloudy exhaust gas in which mist and dust are adsorbed and coexist in the flue, Equipped with a vaporizer that vaporizes the mist, a light irradiator that irradiates the area of the flue where the mist is vaporized, and a scattered light detector that detects the scattered light reflected by the dust from which the mist has been removed. The dust concentration in the cloudy exhaust gas is calculated based on the scattered light intensity detected by the scattered light detector.

The light scattering type dust densitometer described in Patent Document 2 is a dust densitometer that directly measures the dust concentration in the cloudy exhaust gas inside the flue, and the measurement target after separating the measurement target cloudy exhaust gas inside the flue A vaporizer that vaporizes the mist in the cloudy exhaust gas, and an air blower mechanism that forms an air curtain that separates the region in which the mist remains vaporized through the vaporizer from the cloudy exhaust gas that does not pass through the vaporizer downstream of the vaporizer. And the like, and is configured to detect the scattered light reflected by the mist-removed dust in the air curtain to determine the dust concentration in the cloudy exhaust gas.

The light scattering type dust densitometer described in Patent Document 3 takes in the measurement target cloudy exhaust gas in the flue, vaporizes the mist by the vaporizer, and reflects the mist-removed dust in the vaporized region of the mist. In a dust concentration meter that detects scattered light and directly measures the dust concentration in the cloudy exhaust gas in the flue, an intermittent air blow mechanism that intermittently generates air near the intake port of the cloudy exhaust gas to be measured by the vaporizer ( It is equipped with a function to prevent dirt on the entrance side of the vaporizer.

Japanese Patent No. 5453607 Patent No. 59778585 Japanese Patent No. 6204941

Here, in continuous exhaust gas measurement systems such as CEMS (Continuous Emission Monitoring System) in the United States and AMS (Automated Measuring System) in Europe and ISO standards, the continuous exhaust gas measurement system near the inner surface of a flue such as a chimney Considering the influence of the boundary layer of the exhaust gas flow that occurs in the exhaust gas, for example, in the cross-sectional view of the circular shape of the flue, the exhaust gas in the central region with a diameter of 30 cm centering on the axial center of the flue is sampled, It is required to measure the dust concentration inside.

On the other hand, in the light scattering type dust densitometers of Patent Document 1, Patent Document 2 and Patent Document 3 by the inventor of the present application, a through hole is formed on the side surface of a skeleton or other body forming a flue, and light is passed through this through hole. The scattering dust concentration meter is fitted and installed, and the dust concentration of the cloudy exhaust gas is continuously measured on the inner peripheral surface side of the continuous exhaust gas measurement system of the United States, Europe, and ISO. It has been sufficiently confirmed that the dust concentration can be measured accurately and accurately even if the measurement is performed on the inner peripheral surface side of the flue.

However, there are cases in which it is required to continuously measure the dust concentration of the cloudy exhaust gas in the central region of the flue in accordance with the US, Europe, and ISO systems, and the dust concentration of the cloudy exhaust gas by the inventor of the present application. The light scattering type dust densitometers of Patent Document 1, Patent Document 2 and Patent Document 3 having excellent performance of continuously measuring the exhaust gas can be applied to the continuous measurement of the dust concentration of the exhaust gas in the central region of the flue. Was desired.

The present invention, in view of the above circumstances, in the central region of the flue, the dust concentration of the cloudy exhaust gas containing a large amount of mist is continuously and accurately, and a light scattering type that enables continuous measurement over a long period of time. It is an object to provide a dust concentration measuring device.

The present inventor has found a means for continuously, accurately, and continuously measuring the dust concentration of exhaust gas containing a large amount of mist in the central region of the flue, and completed the present invention.

(1) The present invention is a dust densitometer for turbid exhaust gas for directly detecting dust in the turbid exhaust gas in which mist and dust are adsorbed and coexisted in the flue to measure the dust concentration in the flue. A vaporizer that is arranged in the flue and takes in the cloudy exhaust gas to be measured and vaporizes the mist, and a light irradiator that emits light to a region where the mist is vaporized, and the light is A dust densitometer body composed of a dust detection device having a scattered light detector for detecting scattered light reflected on the dust, and is disposed through the inside of the flue from the outside to the inside while supporting the dust densitometer body. It is characterized by comprising a dust densitometer support disposed in the road and an arithmetic/control device for obtaining the dust concentration in the cloudy exhaust gas based on the scattered light intensity detected by the scattered light detector.

(2) The invention according to (1) above, wherein the light irradiator and the scattered light detector of the dust densitometer body disposed inside the flue, and the light irradiator disposed outside the flue. An arithmetic/control device is connected by an optical fiber, an electric signal is converted into an optical signal by a light emission control unit of the arithmetic/control device outside the roadside, and the optical signal is transmitted to a light irradiator inside the flue. It is configured to irradiate the exhaust gas with light from the light irradiator by transmitting it through an optical fiber for projecting light, and the optical signal for detecting the optical signal detected by the scattered light detector inside the flue is detected by the optical fiber for receiving the smoke. It may be configured so that it is transmitted to the outside of the flue, converted into an electric signal by the light reception control unit outside the flue, and the dust concentration is obtained by the arithmetic/control device.

(3) The present invention is the above (1) or (2), wherein the dust densitometer support is connected to the dust densitometer main body at a tip disposed inside the flue, and the dust densitometer main body is connected to the outside of the flue. A support bar connected to at least a part of the arithmetic/control device at the rear end thereof and inserted into the flue from the outside to the inside, and from the outer peripheral surface of the support bar to the axis center of the support bar. A reinforcing rib that projects radially outward and extends along the axial direction of the support bar; and a support bar holding member that fits into a mounting hole formed through the flue and holds the support bar. Good.

(4) In the present invention according to any one of (1) to (3), the vaporizer includes a metal inner cylinder, a sheath heater wound around an outer circumference of the inner cylinder, and the vaporizer. A first container that forms an outer shell, the dust detection device includes a second container that houses the light irradiator and the scattered light detector, and forms an outer shell of the dust detection device, and the first container The second container and the second container may be formed using a resin member.

(5) In the present invention according to the above (4), the resin member forming the first container and the second container is a fluororesin such as PTFE, PFA, or PVDF, or carbonized with the fluororesin. It may be formed using a composite resin in which silicon is mixed.

(6) In the present invention according to any one of (1) to (5) above, the first container may be formed in a rectangular box shape by assembling a plurality of members.
In the present invention, "rectangular box shape" includes "substantially rectangular box shape".

According to the present invention, the dust concentration of the cloudy exhaust gas containing a large amount of mist is continuously, accurately, and long-term in the central region of the flue according to the continuous exhaust gas measurement system of the United States, Europe and ISO method. It becomes possible to measure continuously.

Therefore, according to the light-scattering dust densitometer of the present invention, it becomes possible to realize a light-scattering dust densitometer of cloudy exhaust gas with higher reliability, versatility and applicability.

It is a figure showing the light scattering type dust concentration meter concerning one embodiment of the present invention, and is a figure showing the state where it was attached to the flue. It is a figure which shows typically the principle which measures the dust concentration in a cloudy exhaust gas with the light-scattering type dust concentration meter which concerns on one Embodiment of this invention. It is a block diagram showing a light scattering type dust concentration meter concerning one embodiment of the present invention. It is a sectional view showing a dust concentration meter body of a light scattering type dust concentration meter concerning one embodiment of the present invention. FIG. 6 is a view taken along line X1-X1 of FIG. FIG. 5 is a view taken along line X2-X2 of FIG. FIG. 5 is a view taken along line X3-X3 of FIG. FIG. 2 is a view taken along line X1-X1 of FIG.

Hereinafter, a light scattering dust concentration meter for cloudy exhaust gas according to an embodiment of the present invention will be described with reference to FIGS. 1 to 8. Here, in the present embodiment, the dust concentration in the flue is below the dew point, mist and dust are adsorbed and coexist, and the dust concentration in the cloudy exhaust gas that is clouded is continuously, accurately, and long-term in the flue. The present invention relates to a light-scattering dust concentration meter for cloudy exhaust gas that can be continuously measured over a period of time, and in particular, a light-scattering dust concentration meter for cloudy exhaust gas that can measure the dust concentration of cloudy exhaust gas in the central region of a flue. It concerns a densitometer.

As shown in FIGS. 1 and 2, the light-scattering dust densitometer (light-scattering dust densitometer for cloudy exhaust gas) 100 of the present embodiment has a flow direction T of the cloudy exhaust gas 2 in the flue 1 as shown in FIGS. The vaporizer A1 is arranged on the upstream side, the mist 3 is vaporized by the vaporizer A1, and the dust detector A2 downstream of the vaporizer A1 irradiates the measurement light 4 and detects the scattered light 6 reflected on the dust 5. , The dust concentration is measured by light scattering intensity.

Specifically, the light scattering type dust densitometer 100 of the present embodiment, as shown in FIGS. 1, 2 and 3, is a dust densitometer main body A, a dust densitometer support B, and a calculation/control device C. And is configured.

As shown in FIGS. 1 to 4, the dust densitometer main body A takes in the cloudy exhaust gas 2 flowing through the flue 1 while maintaining its flow, and vaporizes the mist 3 in the cloudy exhaust gas 2 by a vaporizer A1. And a dust detector A2 for measuring the dust concentration in the exhaust gas (2) after being vaporized by the vaporizer A1, a first air blow mechanism 8, a second air blow mechanism 9, and a third air blow mechanism 10. I have it.

As shown in FIGS. 4 to 7 (and FIGS. 2 and 3), the vaporizer A1 is an inner cylinder which is formed in a cylindrical shape and whose axial direction O1 is aligned with the flow direction T of the cloudy exhaust gas 2. (Heater tube) 11, sheath heater 12 wound around outer circumference of inner cylinder 11, heat transfer material 13 covering outer peripheral surface of inner cylinder 11 so as to embed sheath heater 12, inner cylinder 11, sheath heater 12 The first container 15 that forms the outer shell of the vaporizer A1 and the heat insulating material 14 arranged so as to enclose the heat transfer material 13 and that houses the inner cylinder 11, the sheath heater 12, the heat transfer material 13, and the heat insulating material 14. It has and.

The inner cylinder 11 is formed using a metal material such as a copper material having excellent thermal conductivity. In the present embodiment, the inner cylinder 11 is formed by combining a copper material and a nickel material, and thus the inner cylinder 11 having extremely high thermal conductivity and excellent heat resistance and corrosion resistance is realized.

As the sheath heater 12, for example, a 220V/600W sheath heater 12 is wound around the inner cylinder 11 and used. Note that one sheath heater 12 may be used or a plurality of sheath heaters 12 may be wound around the inner cylinder 11 as a matter of course.

The heat transfer material 13 is, for example, heat transfer cement, and by covering the outer peripheral surface of the inner cylinder 11 with this heat transfer material 13 and burying the sheath heater 12 with the heat transfer material 13, the heat generated by the sheath heater 12 is generated. Can be effectively propagated in the direction of the axis O1 of the inner cylinder 11, and the entire inner cylinder 11 can be effectively heated to a predetermined temperature. Further, by providing such a heat transfer material 13 (and the sheath heater 12 and the heat insulating material 14), a large heat distribution is not generated in the entire inner cylinder 11, that is, the temperature distribution of the inner cylinder 11 is reduced. It becomes possible to heat (substantially equalize), and it becomes possible to efficiently heat the inner cylinder 11 to a high temperature of 500° C. or higher.

The heat insulating material 14 is a fiber heat insulating material having excellent heat resistance such as glass wool or rock wool, or a foam heat insulating material having excellent heat resistance such as phenol foam, and the fiber heat insulating material is particularly preferable.

The first container 15 forming the outer shell of the vaporizer A1 has an inlet (entrance opening) 20 on one end side of the inner cylinder 11 communicated with the outside, and has a plate surface orthogonal to the axis O1 of the inner cylinder 11 and the inner cylinder 11. While making the inlet side shield plate portion 21 arranged on one end side of the inner cylinder 11 communicate with the outlet (outlet opening) 22 on the other end side of the inner cylinder 11 to the outside, the plate surface is orthogonal to the axis O1 of the inner cylinder 11. The outlet side shield plate portion 23 disposed on the other end side of the inner cylinder 11 and the both end sides are joined to the outer peripheral surfaces of the inlet side shield plate portion 21 and the outlet side shield plate portion 23, and the inner cylinder 11 and the sheath heater 12 are connected. , A cover portion 24 arranged so as to surround the heat transfer material 13 and the heat insulating material 14, and an inlet side shield so as to house the inner cylinder 11, the sheath heater 12, the heat transfer material 13, and the heat insulating material 14 together with the cover portion 24. The light scattering type dust densitometer 100 is fixed to a body or the like forming the flue 1, which is disposed so as to be joined to the outer peripheral surfaces of the plate portion 21 and the outlet side shield plate portion 23, the sheath heater 12 and various

air blow mechanisms

8, 9 10 and the like, and a board-shaped base portion 25 used for inserting and connecting pipes.

The inner cylinder 11, the sheath heater 12, the heat transfer material 13, and the heat insulating material 14 are housed in a sealed state by the inlet side shield plate portion 21, the outlet side shield plate portion 23, the cover portion 24, and the base portion 25.

In this embodiment, a sealant such as a silicone sealant is applied to the joints of the entrance side shield plate part 21, the exit side shield plate part 23, the cover part 24 and the base part 25.

As shown in FIGS. 4 and 6, in the inlet-side shield plate portion 21, the through-hole portion that forms the inlet opening 20 on one end side of the inner cylinder 11 is located inside from the radially outer side about the axis O1 of the inner cylinder 11. As it goes toward the axis O1 side of the cylinder 11, it is formed as an inclined surface (tapered surface) 21a that gradually goes from the front surface where the inlet 20 opens to the inner surface on the rear side in the axis O1 direction. As a result, the cloudy exhaust gas 2 can be smoothly introduced into the inner cylinder 11 from the inlet 20 on one end side of the inner cylinder 11.

In the first container 15, the inlet side shield plate portion 21, the outlet side shield plate portion 23, the cover portion 24, and the base portion 25 are formed using a resin material. This makes it possible to reduce the weight of the light-scattering dust densitometer 100, and even when the cloudy exhaust gas 2 is exposed for a long time, the cloudy exhaust gas 2 contains corrosive substances such as hydrochloric acid. Even if it is present, it is possible to form a container having excellent corrosion resistance and durability that is unlikely to cause corrosion or damage.

Further, by forming the entrance-side shield plate portion 21, the exit-side shield plate portion 23, the cover portion 24, and the base portion 25 using a resin material, it is possible to easily replace the member when damage is caused by impact or the like. The light scattering type dust densitometer 100 which can be performed and has excellent maintainability can be realized.

Further, the first container 15 is preferably made of a fluororesin such as PTFE (polytetrafluoroethylene (tetrafluoroethylene resin)), PFA (perfluoroalkoxy fluororesin), PVDF (polyvinylidene fluoride), or the like. It is more preferable to use a resin material in which carbon is mixed with resin. By using such a fluorine resin or a carbon-containing fluorine resin, it becomes possible to more effectively form a container having excellent corrosion resistance and durability.

Note that the first container 15 may be formed using a metal material, for example, a stainless material such as SUS304, or a member obtained by coating a stainless resin with a fluorine resin.

The first container 15 is formed in a rectangular box shape (including a substantially rectangular box shape). When the first container 15 is formed in a rectangular box shape in this manner, the cover portion 24 can be easily attached, processed, replaced, and the like, and the hermeticity can be easily ensured.

Since the vaporizer A1 includes the inner cylinder 11, the sheath heater 12, the heat transfer material 13, the heat insulating material 14, and the first container 15 described above, for example, the inner cylinder 11 can be heated to a high temperature of 500° C. or higher. .. As shown in FIGS. 2 and 4, in order to measure and control the temperature of the sheath heater 12 and the like, a thermocouple 27 as a temperature measuring means is arranged inside the first container 15.

As shown in FIGS. 4, 5, and 7 (and FIGS. 2 and 3), the dust detection device A2 has an outlet opening 22 (an outlet side shield plate portion 23) on the other end side of the inner cylinder 11 of the vaporizer A1. A light irradiator 30 which is provided adjacent to the downstream side of the exhaust gas 2 in the flow direction T and vaporizes the mist 3 by the vaporizer A1 to irradiate the exhaust gas 2 emitted from the outlet opening 22 with light 4. The scattered light detector 31 for detecting the scattered light 6 reflected by the dust 5 contained in the gas 2 and the second container which forms the outline of the dust detection device A2 and accommodates the light irradiator 30 and the scattered light detector 31. And 32.

The second container 32, which forms the outer shell of the dust detection device A2, has a rectangular box shape (including a substantially rectangular box shape) that includes the light irradiator 30 and the scattered light detector 31 while sharing the base portion 25 of the first container 15. ) Is formed. Further, a circular through hole 32a is formed on the upper surface facing the exhaust gas 2 side immediately after exiting the outlet opening 22 of the vaporizer A1, and the light irradiator 30 and the scattered light detector 31 are held in this through hole 32a. The holding block 32b is fitted and provided.

In addition, the holding block 32 b causes the light 4 emitted from the light irradiator 30 inside the second container 32 to be projected toward the exhaust gas 2, and the scattered light 6 reflected by the dust 5 inside the second container 32. A light transmitting member (light transmitting surface: light projecting surface and light receiving surface) 32c for allowing the scattered light detector 31 to receive light is provided. In addition, in the present embodiment, the sealing state of the inside of the second container 32 is secured by using the sealing material such as the holding block 32b and the O-ring 32d, and the packing material.

Like the first container 15, the second container 32 of the present embodiment is made of a resin material. This makes it possible to reduce the weight of the light-scattering dust densitometer 100, and even when the cloudy exhaust gas 2 is exposed for a long time, the cloudy exhaust gas 2 contains corrosive substances such as hydrochloric acid. Even if it is present, it is possible to form a container having excellent corrosion resistance and durability that is unlikely to cause corrosion or damage. Further, by using the resin material, it is possible to easily replace the member when it is damaged due to impact or the like, and it is possible to realize the light scattering type dust densitometer 100 excellent in maintainability.

Further, the second container 32, like the first container 15, is made of a fluorine-based resin such as PTFE (polytetrafluoroethylene (tetrafluoroethylene resin)), PFA (perfluoroalkoxy fluororesin), PVDF (polyvinylidene fluoride). It is preferable to use. Further, it is more preferable to use a composite resin material in which carbon (silicon carbide) is mixed in a fluororesin. By using such a fluorine resin or a carbon-containing fluorine resin, it becomes possible to more effectively form a container having excellent corrosion resistance and durability.

Of course, the second container 32 may be formed by using a metal material, like the first container 15, and may be formed by using a member obtained by coating a stainless steel material such as SUS304 with a fluorine resin, for example.

As shown in FIG. 4, the light irradiator 30 has a region S1 in which only dust 5 exists in an air curtain (air curtain whose details will be described later) 33 downstream of the vaporizer A1 in the flow direction T of the cloudy exhaust gas 2. Part of the scattered light detection area S2 is irradiated with the measurement light 4 for detecting the scattered light 6 which is the basis of the measurement of the dust concentration as diffused light. At that time, it is preferable to irradiate the measurement light 4 which is synchronously detected with a constant wavelength.

The scattered light detector 31 detects scattered light 6 scattered by the measurement light 4 being reflected by the dust 5 from which the mist 3 has been removed via the vaporizer A1.

The scattered light detection area S2 (area S1) is adjacent to the cloudy exhaust gas area S3 that has not passed through the vaporizer A1, but the surrounding cloudy exhaust gas 2 is blocked by the air curtain 33 and vaporized by the vaporizer A1. By irradiating the exhaust gas 2 with the measurement light 4 that has not been mixed with the exhaust gas 2 and is synchronously detected at a constant wavelength, the scattered light 6 scattered by the dust 5 in the scattered light detection area S2 and the vaporizer A1 are separated. The scattered light 6 scattered by the mist 3 and the mist adsorbed dust 5 in the white turbid exhaust gas 2 which has not passed is a scattered light 6 having a different wavelength, which can be identified by the scattered light detector 31.

Further, even if the scattered light 6 having the same wavelength as the scattered light 6 generated from the scattered light detection area S2 is generated from the adjacent or mixed white turbid exhaust gas 2 which has not passed through the vaporizer A1, the amount is extremely low. Further, since the light intensity of the scattered light detection area S2 is extremely strong, the amount of scattered light 6 from the cloudy exhaust gas 2 can be ignored.

Further, the inventor of the present application sets the intersecting angle θ between the optical axis of the light irradiator 30 and the optical axis of the scattered light detector 31 to be 45° to 90°, preferably 60°, so that the exhaust gas vaporized by the vaporizer A1 is exhausted. It has been found that the dust 5 in 2 can be reliably and suitably detected by the dust detection device A2.

The light-scattering dust densitometer 100, as shown in FIGS. 3, 4, and 6, is provided with a first air blow mechanism 8 for ejecting intermittent air toward the inlet 20 side of the cloudy exhaust gas 2.

The first air blow mechanism 8 includes a first flow path 8a that allows intermittent air to pass through the inlet side shield plate portion 21 of the first container 15, and an inner surface on the rear side in the axis O1 direction from the front surface where the inlet 20 on one end side of the inner cylinder 11 is open. It is provided on the inclined surface (tapered surface) 21a of the entrance-side shield plate portion 21 facing toward, and has a large number of air discharge ports 8b communicating with the first flow path 8a.

When the intermittent air is supplied to the first flow path 8a, the first air blow mechanism 8 ejects the air from the plurality of air discharge ports 8b. By the air blow of the first air blow mechanism 8, the mist 3 condensed at the inlet 20 side portion (the through hole portion of the inlet side shield plate portion 21) which is the intake of the cloudy exhaust gas 2 can be dried or blown off. Further, since the inside of the through hole portion is formed as the inclined surface 21a, the mist 3 and the air blower flow from the first container 15 to the outside. As a result, it is possible to prevent the mist 3 from aggregating and accumulating the drain on the inlet 20 side of the intake port for the cloudy exhaust gas 2 of the first container 15.

As shown in FIGS. 3, 4, and 7, the light-scattering dust densitometer 100 includes a region (air flow) S1 in which the mist 3 is maintained in a vaporized state through the vaporizer A1 and white turbidity that does not pass through the vaporizer A1. A second air blow mechanism 9 is provided for forming an air curtain 33 that separates and isolates the exhaust gas region S3.

The second air blower mechanism 9 is provided in the outlet side shield plate portion 23 of the first container 15 and opens toward the downstream side in the flow direction T of the outlet side shield plate portion 23 and the second flow passage 9a through which air is always passed. The air outlet 9b is provided along the outer peripheral edge of the outlet-side shield plate 23 and communicates with the second flow passage 9a.

As a result, the second air blow mechanism 9 ejects air toward the downstream side in the flow direction T of the cloudy exhaust gas 2 and maintains the state S1 in which the mist 3 is vaporized through the vaporizer A1 and the vaporizer A1. The air curtain 33 for separating and isolating the region S3 of the white turbid exhaust gas 2 that does not pass through, preventing the mist 3 from mixing into the scattered light detection region S1 (S2), and detecting the scattered light 6 without the influence of the mist 3. Can be formed. That is, such an air curtain 33 can form the isolation space (S1) on the second container 32.

Note that the air discharge port 9b is provided along the outer peripheral edge of the first container 15 up to the upper surface of the second container 32. At this time, the air discharge port 9b may be formed by interspersing a plurality of holes, or may be formed by extending one opening into a line.

In the light scattering type dust densitometer 100, as shown in FIG. 3, FIG. 4, and FIG. 7, in addition to the above-described first air blow mechanism 8 and second air blow mechanism 9, the light transmitting surface (projecting light) of the second container 32 is used. Surface, light receiving surface) 32c is provided with a third air blow mechanism (air blow mechanism for light transmitting surface) 10 for preventing drain accumulation due to condensation of mist 3 and adhesion and accumulation of dust 5 on the drain. ..

The third air blow mechanism 10 is provided in the outlet-side shield plate portion 23 of the first container 15 and has a second flow path 9a (10a) through which air flows constantly or intermittently, and a flow direction T of the outlet-side shield plate portion 23. The opening is opened toward the downstream side, and is provided below the outlet opening 22 of the outlet-side shield plate portion 23 between the outlet opening 22 and the upper surface of the second container 32 along the width direction. (10a) and an air discharge port 10b communicating with (10a).

As a result, the third air blow mechanism 10 is directed toward the downstream side in the flow direction T of the exhaust gas 2 inside the air curtain 33 and toward the light transmitting surface 32c (on the light transmitting surface) of the second container 32. It is possible to prevent (suppress) the accumulation of drain due to the condensation of the mist 3 on the transparent surface 32c of the second container 32 and the adhesion and accumulation of the dust 5 on the drain, by ejecting air to blow off the mist 3 and the like.

Here, as shown in FIG. 3, the first air blow mechanism 8, the second air blow mechanism 9, and the third air blow mechanism 10 include an air supply source (not shown), an air supply source, a first flow path 8a, and a second flow path. A pipe 34 connecting the flow path 9a (10a) and an electromagnetic valve 35 provided in each pipe 34 are provided. Then, air is intermittently supplied to the first flow path 8a by controlling the opening/closing of the electromagnetic valve 35, and the second flow path 9a (10a) is supplied with an electromagnetic valve (not shown) during normal measurement except for maintenance. ) Is released and air is constantly supplied.

Since the air blow by the first air blow mechanism 8 affects the dust detection value, the CPU records the dust detection value immediately before the air blow on the recording device in conjunction with the timing of the air blow, and displays the air blow in the air blower on the display unit. It is preferable to display the measured concentration so as to eliminate the influence on the continuous indication.

When the air blow by the third air blow mechanism 10 may affect the dust detection value as in the case of the first air blow mechanism 8, the flow path 10a of the third air blow mechanism 10 may be provided independently, or The first air flow mechanism 8 is connected to the first flow path 8a of the first air flow mechanism 8, or the pipe connected to the first flow path 8a of the first air flow mechanism 8 is connected to the flow path 10a of the third air flow mechanism 10. Air may be intermittently supplied to the flow path 10a to blow off the mist 3 and the like.

As shown in FIG. 1, FIG. 2, and FIG. 3, the arithmetic/control unit C calculates the dust concentration from the light intensity of the scattered light 6 based on the scattered light 6 having a proportional relationship with the dust concentration. 36, and a temperature adjustment control device 37 that adjusts the temperature of the sheath heater 12 and the like. For example, if a calibration curve having a proportional relationship between the dust concentration and the light amount is created in advance, the dust concentration with respect to the detected light amount of the scattered light 6 can be obtained from the calibration curve.

Further, the arithmetic/control unit C is connected to the light irradiator 30 by a light projecting optical fiber 38, receives an electric signal, and irradiates light (light signal) corresponding to the electric signal through the light projecting optical fiber 38. The light emission control unit 39 to be emitted from the device 30 is connected to the scattered light detector 31 by the light receiving optical fiber 40, and the light (optical signal) received by the scattered light detector 31 is received through the light receiving optical fiber 40. , And a signal conversion control device 42 including a light reception control unit 41 for transmitting an electric signal corresponding to the optical signal to the arithmetic device 36.

That is, in the light scattering type dust densitometer 100 of the present embodiment, the dust detection device A2 and the arithmetic/control device C are connected by the

optical fibers

38 and 40. Then, as shown in FIGS. 1 and 3, as will be described later in detail, a dust densitometer main body A including a vaporizer A1 and a dust detector A2 is arranged in a central region 1a inside the flue 1, and calculation/control is performed. The device C is arranged outside the flue 1, and the light emission control unit 39 outside the flue 1 converts an electric signal into an optical signal, and the optical signal is transmitted to the light irradiator 30 inside the flue 1 by the optical fiber 38. And the exhaust gas 2 is irradiated with light from the light irradiator 30. Further, the optical signal detected by the dust detection device A2 inside the flue 1 is transmitted to the outside of the flue 1 by the optical fiber 40, and is converted into an electric signal by the light reception control unit 41 outside the flue 1, and the arithmetic unit 36 Is configured to obtain the dust concentration by this electric signal.

As shown in FIG. 3, the arithmetic/control unit C of the present embodiment includes a control box C1 and a relay box C2, for example, power supply, storage and display of measured values, automatic calibration signal and failure alarm signal. Is connected to the instrument room D for transmitting signals such as.

On the other hand, in the dust densitometer support B, as shown in FIGS. 1, 4, and 6 to 8, the dust densitometer main body A including the vaporizer A1 and the dust detector A2 is provided in the central region of the flue 1. 1a for placing and supporting the metal supporting bar B1 having a corrosion resistance and a predetermined proof strength, and a mounting hole 26a formed in the body 26 or the like forming the flue 1 The support bar B1 inserted in the mounting hole 26a while sealing the portion 26a is indirectly or directly in a radial direction orthogonal to the axis O2 of the flue 1 in the direction of the axis O3 of the support bar B1. And a support bar holding member B2 for supporting in a state of facing.

The support bar B1 of the present embodiment is a pipe material such as SUS304, the rear end in the direction of the axis O3 is connected to the relay box C2 of the arithmetic/control unit C, and the front end is connected to the dust densitometer main body A (base portion 25). Then, the dust densitometer main body A is inserted through the mounting hole 26a formed in the frame 26 or the like forming the flue 1 and the dust densitometer main body A is arranged in the central region 1a of the flue 1.

The support bar B1 is provided with a reinforcing rib B3 that projects from the outer peripheral surface radially outward of the center of the axis O3 and extends from the rear end to the tip in the direction of the axis O3.

The reinforcing rib B3 is, for example, a plate material such as SUS304, and one reinforcing rib B3 is integrally provided by welding to the support bar B1. The reinforcing rib B3 is provided so as to project to the downstream side in the flow direction T of the exhaust gas 2 flowing through the flue 1 in a state where the support bar B1 is inserted into the mounting hole 26a and is arranged at a predetermined position.

Further, the reinforcing rib B3 of the present embodiment is formed so as to have a substantially triangular shape in which the protruding amount gradually becomes smaller from the rear end in the axis O3 direction of the support bar B1 toward the front end. That is, the reinforcing rib B3 changes the width dimension (height dimension) according to the stress (bending moment, etc.) acting in the direction of the axis O3 of the support bar B1, and is effective while reducing the weight of the dust densitometer support B. Is provided so that the support bar B1 can be reinforced.

The support bar holding member B2 is, for example, made of metal, and has a tubular body 28 having an outer shape that fits into the mounting hole 26a, a rear end of the tubular body 28 in the axis O4 direction, and a direction orthogonal to the axis O4 from the outer surface. It is formed with a flange 29 that projects outward and extends along the outer periphery and is connected in an annular shape.

The support bar holding member B2 has a support bar B1 (and a reinforcing rib B3) in which the tip end side in the direction of the axis O4 is fitted into the mounting hole 26a, and the axes O3 and O4 are coaxially arranged therein. The flange 29 at the rear end is inserted and bolted to the relay box C2 of the arithmetic/control unit C together with the rear end of the support bar B1. The portion where the tip end side of the support bar holding member B2 is fitted in the mounting hole 26a is sealed or the like to seal the flue 1.

In the light-scattering type dust densitometer 100 of the present embodiment having the above-described configuration, as shown in FIGS. 1 and 8, while being supported by the dust densitometer support B, in the flow direction T of the cloudy exhaust gas 2. The dust densitometer main body A is directed toward the flue 1 with the axial direction O1 of the inner cylinder 11 of the vaporizer A1 directed, the inlet opening 20 directed toward the upstream side T of the cloudy exhaust gas 2 in the flow direction T, and the outlet opening 22 directed toward the downstream side. It is arranged in the central region 1a (for example, a region having a diameter of 30 cm centering on the axis O2 of the flue 1). Further, the calculation/control device C (relay box C2) is provided outside the flue 1 while being supported by the dust densitometer support B.

As a result, in the light scattering type dust densitometer 100 of the present embodiment, in the central region 1a inside the flue 1, the turbid exhaust gas 2 is taken into the inside of the inner cylinder 11 of the vaporizer A1 and the turbid exhaust gas 2 The mist 3 is vaporized, the exhaust gas 2 vaporized by the mist 3 is irradiated with the measurement light 4 by the light irradiator 30 of the dust detection device A2, and the scattered light 6 reflected by the dust 5 is detected by the scattered light detector 31. The dust concentration can be measured.

Also, in the central area 1a inside the flue 1, it becomes possible to continuously, accurately, and continuously measure the dust concentration of the cloudy exhaust gas 2 for a long period of time.

Therefore, according to the light scattering type dust densitometer 100 of the present embodiment, the turbid exhaust gas containing a large amount of mist in the central region 1a of the flue 1 conforms to the continuous exhaust gas measurement system of the United States, Europe and ISO method. It becomes possible to measure the dust concentration of 2 continuously, accurately and continuously over a long period of time, and realize the light scattering type dust concentration meter 100 of the cloudy exhaust gas 2 which is more reliable, versatile and applicable. It becomes possible to do.

Further, in the light scattering type dust densitometer 100 of the present embodiment, the first container 15 of the vaporization device A1 and the second container 32 of the dust detection device A2 are formed by using resin members, It is possible to reduce the weight of the light scattering dust densitometer 100. Thereby, even when the dust densitometer main body A is attached to and supported by the tip of the dust densitometer support B, the handling property can be improved.

Since the first container 15 of the vaporizer A1 and the second container 32 of the dust detector A2 are formed of resin members, even when the cloudy exhaust gas 2 is exposed for a long time, Even if the cloudy exhaust gas 2 contains a corrosive substance such as hydrochloric acid, a container excellent in corrosion resistance and durability that hardly causes corrosion, damage, etc., and thus a light scattering dust concentration meter 100 is formed. It is possible to configure.

Here, when the dust densitometer main body A is attached to and supported by the tip of the dust densitometer support B, for example, when the light scattering dust densitometer 100 is transported or installed. It is also conceivable that the dust densitometer main body A is applied to the skeleton 26 forming the flue 1 and the first container 15 and the second container 32 are damaged. On the other hand, in the present embodiment, the first container 15 of the vaporizer A1 and the second container 32 of the dust detector A2 are formed by using resin members, so that when the members are damaged by impact or the like, Can be easily replaced, and the light scattering dust densitometer 100 excellent in maintainability can be realized.

Further, the resin members of the first container 15 and the second container 32 are made of fluorine such as PTFE (polytetrafluoroethylene (tetrafluoroethylene resin)), PFA (perfluoroalkoxy fluororesin), PVDF (polyvinylidene fluoride). A container (light scattering type dust densitometer 100) with excellent corrosion resistance and durability can be obtained more effectively by using a resin based resin or a resin material in which carbon is mixed with a fluorine based resin. Can be formed.

In addition, by assembling the first container 15 and the second container 32 into a rectangular box shape by assembling a plurality of members, each member can be easily attached, processed, replaced, etc., and the hermeticity is easy. It becomes possible to secure.

Although one embodiment of the light-scattering dust concentration meter for cloudy exhaust gas according to the present invention has been described above, the present invention is not limited to the above-mentioned one embodiment, and may be appropriately changed without departing from the spirit of the present invention. It can be changed.

For example, in the present embodiment, the dust densitometer support body B is used to dispose the dust densitometer main body A including the vaporizer A1 and the dust detector A2 in the central region 1a of the flue 1. It is not necessary to arrange the dust densitometer main body A in the central region 1a of the flue 1, but the length of the dust densitometer support B can be adjusted to move the dust densitometer main body A to the inside of the flue 1. It may be arranged at a desired position and used to measure the dust concentration of the cloudy exhaust gas 2 at a desired position inside the flue 1.

The light-scattering dust concentration meter for cloudy exhaust gas of the present invention can be easily and inexpensively attached to an existing flue. Moreover, only the dust in the cloudy exhaust gas below the dew point, which was difficult until now, can be continuously fed directly to the central region of the flue without being affected by other mist even if the flow of the cloudy exhaust gas is low. For people who are worried that the flow rate can be measured accurately, accurately, and continuously over a long period of time, so it is highly versatile and reliable, and that it may exceed the standard value for cloudy exhaust gas. Can provide evidence. Furthermore, it can be used for white smoke prevention measures. Therefore, it can be expected to make a great contribution to the technical field and industry of exhaust gas measurement.

1 Flue 1a Central area 2 Cloudy exhaust gas 3 Mist 4 Measuring light (light)
5 Dust 6 Scattered light 7 Operation control device 8 First air blow mechanism 9 Second air blow mechanism (air blow mechanism for air curtain)
10 3rd air blower mechanism (air blower mechanism for translucent surface)
10b Air discharge port 11 Inner cylinder 12 Sheath heater 13 Heat transfer material 14 Heat insulating material 15 First container 20 Inlet (inlet opening)
21 Inlet-side shield plate 22 Outlet (outlet opening)
23 Outlet Side Shielding Plate 24 Cover 25 Base 26 26 Body Forming Flue 26a Mounting Hole 27 Thermocouple 30 Light Irradiator 31 Scattered Light Detector 32 Second Container 32c Light Transmitting Member (Light Transmitting Surface: Light Emitting Surface) And light receiving surface)
33 Air Curtain 36 Arithmetic Device 38 Optical Fiber 39 for Projecting Light Projection Control Unit 40 Optical Fiber 41 for Receiving Light Reception Control Unit 100 Light Scattering Dust Densitometer A for White Cloudy Exhaust Gas Dust Densitometer Main Body A1 Vaporizer A2 Dust Detector B Dust Densitometer Support B1 Support Bar B2 Support Bar Holding Member B3 Reinforcing Rib C Calculation/Control Device C1 Control Box C2 Relay Box D Instrument Room O1 Inner Cylinder Axis O2 Flue Shaft O3 Support Bar Axis O4 Support Bar Axis S1 of the holding member Region where the mist is kept vaporized through the vaporizer (region where the mist is vaporized)
S2 Scattered light detection area S3 White turbid exhaust gas area T not passing through vaporizer T White turbid exhaust gas flow direction

Claims

A dust densitometer for cloudy exhaust gas for measuring dust concentration by directly detecting dust in the cloudy exhaust gas coexisting with mist and dust in the stack,
A vaporizer that is disposed in the flue and takes in the cloudy exhaust gas to be measured and vaporizes the mist, a light irradiator that irradiates light to a region in which the mist is vaporized, and the light is the dust. A dust densitometer body comprising a dust detection device having a scattered light detector for detecting scattered light reflected by
A dust densitometer support disposed inside the flue from the outside to support the dust densitometer body while supporting the dust densitometer body.
A light scattering dust densitometer for cloudy exhaust gas, comprising: a calculation/control device for determining the dust concentration in the cloudy exhaust gas based on the scattered light intensity detected by the scattered light detector.
The light irradiator and the scattered light detector of the dust densitometer main body arranged inside the flue, and the arithmetic/control device arranged outside the flue are connected by an optical fiber,
An electric signal is converted into an optical signal by a light emission control unit of the arithmetic/control device outside the roadside, and the optical signal is transmitted to an optical irradiator inside the flue by an optical fiber for light emission to transmit the light. Configured to illuminate the exhaust gas from the illuminator,
An optical signal detected by the scattered light detector inside the flue is transmitted to the outside of the flue through an optical fiber for receiving light, and is converted into an electric signal by a light reception control unit outside the flue to perform the calculation/ The light-scattering dust concentration meter for cloudy exhaust gas according to claim 1, wherein the control device is configured to determine the dust concentration.
The dust densitometer support has the dust densitometer main body connected to the tip disposed inside the flue, and at least a part of the arithmetic/control device at the rear end disposed outside the flue. A support bar that is connected and inserted from the outside of the flue to the inside,
Reinforcing ribs protruding from the outer peripheral surface of the support bar radially outward of the axis of the support bar and extending along the axis of the support bar.
The light-scattering dust concentration meter for cloudy exhaust gas according to claim 1 or 2, further comprising: a support bar holding member that fits into a mounting hole formed through the flue to hold the support bar.
The vaporizer is
A metal inner tube,
A sheath heater wound around the outer circumference of the inner cylinder,
A first container forming an outer shell of the vaporizer,
The dust detection device includes a second container that houses the light irradiator and the scattered light detector, and forms an outer shell of the dust detection device.
The light scattering dust concentration meter for cloudy exhaust gas according to any one of claims 1 to 3, wherein the first container and the second container are formed by using a resin member.
The resin member forming the first container and the second container is formed by using a fluororesin such as PTFE, PFA, or PVDF, or a composite resin in which the fluororesin is mixed with silicon carbide. The light-scattering dust concentration meter for the cloudy exhaust gas according to claim 4.
The light scattering dust concentration meter for cloudy exhaust gas according to any one of claims 1 to 5, wherein the first container is formed by assembling a plurality of members into a rectangular box shape.