JP2021009084A - Spectral analysis method and spectral analysis device - Google Patents

Abstract

To provide a spectral analysis method capable of measuring an accurate concentration even in a case where it is difficult to perform maintenance of a measurement probe frequently.SOLUTION: A spectroscopic analysis method according to one embodiment comprises: when the optical path length of light passing through liquid to be analyzed is a first optical path length and a second optical path length different from the first optical path length, measuring the intensity of the light passing through the liquid; then, calculating a first absorbance at the time when the optical path length is the first optical path length and the second absorbance at the time when the optical path length is the second optical path length; and calculating the concentration of a component to be analyzed in the liquid based on the calculated first absorbance and second absorbance.SELECTED DRAWING: Figure 6

Description

The present disclosure relates to spectroscopic analysis methods and spectroscopic analyzers.

A spectroscopic analyzer capable of measuring the component concentration in the liquid to be analyzed by immersing the measurement probe in the liquid to be analyzed is known (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2012-32184

For example, in the spectroscopic analyzer described in Patent Document 1 described above, if the measurement probe is installed in a state of being inserted inside a pipe or the like of a plant, the concentration of the component to be measured contained in the liquid inside the pipe or the like can be measured. Can be measured continuously.
For example, in the spectroscopic analyzer described in Patent Document 1 described above, among the parts that the measurement probe comes into contact with the liquid to be analyzed, the part through which the light from the light source of the spectroscopic analyzer transmits is contaminated by the liquid to be analyzed. Then, the correct concentration cannot be measured. Therefore, when the site becomes dirty, it is necessary to perform maintenance of the measurement probe such as removing the dirt on the site.
However, it is derived from distance reasons such as the installation location of the measurement probe being far away, accessibility reasons such as the installation location of the measurement probe being narrow, work environment reasons such as ambient temperature, and the properties of the liquid. When there is a reason such as a reason that it is not easy to remove the measurement probe from the pipe or the like, it is difficult to perform maintenance of the measurement probe frequently.

In view of the above circumstances, at least one embodiment of the present invention aims to provide a spectroscopic analysis method capable of measuring a correct concentration even when it is difficult to frequently maintain a measuring probe.

(1) The spectroscopic analysis method according to at least one embodiment of the present invention
The first measurement step of measuring the intensity of the light passing through the liquid when the optical path length of the light passing through the liquid to be analyzed is the first optical path length, and
A second measurement step of measuring the intensity of light passing through the liquid when the optical path length is a second optical path length different from the first optical path length.
A first absorbance calculation step of calculating the first absorbance when the optical path length is the first optical path length based on the intensity measured in the first measurement step.
A second absorbance calculation step of calculating the second absorbance when the optical path length is the second optical path length based on the intensity measured in the second measurement step.
A concentration calculation step of calculating the concentration of the component to be analyzed in the liquid based on the first absorbance calculated in the first absorbance calculation step and the second absorbance calculated in the second absorbance calculation step.
To be equipped.

The concentration of the solution component having the absorption property can be quantified according to Lambert-Beer's law shown in the following formula (f1). From the formula (f1), the absorbance (A) can be obtained from the molar extinction coefficient (e), the component concentration (c), and the optical path length (l). If the molar extinction coefficient e and the optical path length l are known, the absorbance The component concentration c can be obtained by measuring A.
A = -log (I / I ₀ )
= E × c × l ・ ・ ・ (f1)
Here, I ₀ is the incident light, that is, the intensity of the light emitted from the irradiation unit that irradiates the light from the light source in, for example, a spectroscopic analyzer. I is the intensity of transmitted light, that is, light transmitted through the liquid to be analyzed and received by, for example, a light receiving unit in a spectroscopic analyzer. Here, in order to simplify the explanation, the attenuation of light in the light guide path from the light source in the irradiation section of the spectroscopic analyzer to the liquid to be analyzed, and the light transmitted through the liquid to be analyzed are separated. Ignore the attenuation of light in the light guide path until it reaches the light receiving part of the analyzer.
Absorbance A is a dimensionless value. The unit of the molar extinction coefficient e is [mol / L / m]. The unit of the component concentration c is [mol / L]. The unit of the optical path length l is [m].

Here, if dirt is attached to the light transmitting portion irradiated from the irradiation unit, the light is also absorbed by the dirt, so that the absorbance (A') is obtained by adding an increment (β) of the absorbance due to the dirt. It is expressed by the equation (f2).
A'= e × c × l + β ・ ・ ・ (f2)

When there is no dirt on the light transmitting part, the intensity of the light emitted from the irradiation part (incident light intensity I ₀ ), the intensity of the light received by the light receiving part (transmitted light intensity I), and the molar extinction coefficient The component concentration c can be obtained from e and the optical path length l based on the formula (f1).
However, when dirt is attached to the light transmitting portion, the calculated absorbance A'contains the absorbance β due to the dirt, so that there are two unknowns (β and c) for one equation. Therefore, the component concentration c cannot be obtained as it is.

Therefore, if two equations are obtained by measuring the absorbance A by changing the optical path length l, the component concentration c can be obtained by combining these two equations, and the absorbance increment β due to dirt can be obtained. Can also be asked.
From the formula (f1), when the molar extinction coefficient e and the component concentration c are constant, when the optical path length l is lengthened, the absorbance A also increases in proportion to the optical path length l. The absorbance (A ″) when the optical path length l is multiplied by a is expressed by the following equation (f3).
A'' = a × e × c × l + β ・ ・ ・ (f3)

According to the method (1) above, the light intensity I can be measured at the first optical path length and the second optical path length different from the first optical path length, respectively, so that the first absorbance at the first optical path length can be measured. A1 and the second absorbance A2 at the second optical path length can be obtained. Here, since the change multiple a of the optical path length l and the optical path length l are preset values and the molar extinction coefficient e is known because of the physical property value, the unknowns are the component concentration c and the absorbance due to dirt. There are two increments of β. Since there are two equations obtained by changing the optical path length l for two unknowns, the component concentration c can be obtained by the following equation (f4) based on the equations (f2) and (f3). Then, the increment β of the absorbance due to dirt can be obtained by the following equation (f5).
c = (A2-A1) / {e × l × (a-1)} ・ ・ ・ (f4)
β = (a × A1-A2) / (a-1) ... (f5)

As described above, according to the method (1) above, the component concentration c can be obtained even when dirt adheres to the light transmitting portion irradiated from the irradiation unit, for example, in the spectroscopic analyzer. Therefore, according to the method (1) above, the correct component concentration c can be measured even when it is difficult to frequently perform maintenance of the liquid distribution section where the liquid to be analyzed can be distributed in the spectroscopic analyzer, for example. ..

(2) In some embodiments, in the method of (1) above, the concentration calculation step involves incident of the light on a liquid distribution section filled with the liquid to be analyzed and passing the light through, and the liquid. The density is calculated based on a calculation formula that includes the number of repetitions of light emission from the distribution unit as a parameter.

For example, consider a case where the absorbance when the optical path length becomes the first optical path length is calculated by the above-mentioned formula (f2), and the absorbance when the optical path length becomes the second optical path length is calculated by the above-mentioned formula (f3). ..
Further, in this case, for example, when the optical path length becomes the first optical path length and the second optical path length, for example, when the number of times light is incident and reflected on the liquid flow portion in the spectroscopic analyzer is different. , Will be described below.
In such a case, when the optical path length becomes the first optical path length and when it becomes the second optical path length, the number of repetitions of the light incident on the liquid flow section and the light emission from the liquid flow section is repeated. Because they are different, the values are different between the term of the increase in absorbance due to dirt in the above formula (f2) and the term of the term of increase in absorbance due to dirt in the above formula (f3).
Therefore, for example, the number of repetitions is set to n, and the number of repetitions n is added as a parameter to the term of the increment of absorbance in the equations (f2) and (f3) to calculate the difference in the increase in absorbance due to the difference in the number of repetitions n. It can be reflected in the formula.

Specifically, when the number of repetitions n when the optical path length becomes the first optical path length is n1, and the number of repetitions n when the optical path length becomes the second optical path length is n2, the above equation (f2) is expressed as follows. It can be replaced by the equation (f6), and the above equation (f3) can be replaced by the following equation (f7).
In the following equations (f6) and (f7), β'is an increment of the absorbance due to fouling per repetition number n.
A'= e × c × l + n1 × β'・ ・ ・ (f6)
A'' = a × e × c × l + n2 × β'・ ・ ・ (f7)

Here, as described above, the change multiple a of the optical path length l and the optical path length l are preset values, and the molar extinction coefficient e is known because of its physical property value. Since the number of repetitions n1 and n2 can also be grasped from the device configuration of the spectroscopic analyzer, the unknowns are the component concentration c and the increment β of the absorbance due to dirt. Since there are two equations obtained by changing the optical path length l for two unknowns, the component concentration c can be obtained by the following equation (f8) based on the equations (f6) and (f7). Then, the increment β'of the absorbance due to the stain per repetition n can be obtained by the following equation (f9).
c = {(n2 / n1) x A1-A2} / [{(n2 / n1) -a} x e x l]
... (f8)
β = (A2-a × A1) / (n2-n1 × a) ・ ・ ・ (f9)

As described above, according to the method (2), the number of times the light is incident and reflected on the liquid flow portion differs depending on whether the optical path length is the first optical path length or the second optical path length. Even in this case, the component concentration c and the increment β'of the absorbance due to the above-mentioned stain can be obtained.

(3) In some embodiments, in the method (1) above, the concentration calculation step includes the absorbance of the optical member in contact with the liquid when the optical path length is the first optical path length, and the absorbance due to dirt on the optical member. When the optical path length is the second optical path length, the concentration is calculated based on a calculation formula that takes into consideration the ratio to the absorbance of the optical member due to contamination.

For example, consider a case where the absorbance when the optical path length becomes the first optical path length is calculated by the above-mentioned formula (f2), and the absorbance when the optical path length becomes the second optical path length is calculated by the above-mentioned formula (f3). ..
For example, the optical path may be different when the optical path length is the first optical path length and when it is the second optical path length. For convenience of explanation, in the following description, the optical path when the optical path length becomes the first optical path length is referred to as a first optical path, and the optical path when the optical path length becomes the second optical path length is referred to as a second optical path. When the optical paths are different, such as the first optical path and the second optical path, the light transmission length and the light scattering behavior of the part where the dirt is attached are different for each optical path, and the increase in absorbance due to the dirt per repetition n is repeated. It is possible that β'also differs for each optical path.
Therefore, for example, a coefficient representing the difference in absorbance due to dirt between the first optical path and the second optical path is obtained in advance, and by using this coefficient, the difference in absorbance due to dirt between the first optical path and the second optical path can be used as a calculation formula. Can be reflected.

Specifically, the term of the increase in absorbance in the above equation (f3) is multiplied by a coefficient γ representing the difference in absorbance due to dirt between the first optical path and the second optical path. Therefore, the above equation (f2) can be replaced by the following equation (f10), and the above equation (f3) can be replaced by the following equation (f11).
In the following equations (f10) and (f11), β ″ is an increment of absorbance due to contamination in the first optical path.
A'= e × c × l + β'' ・ ・ ・ (f10)
A'' = a × e × c × l + γ × β'' ・ ・ ・ (f11)

Here, as described above, the change multiple a of the optical path length l and the optical path length l are preset values, and the molar extinction coefficient e is known because of its physical property value. Since the coefficient γ is also obtained in advance, there are two unknowns, the component concentration c and the increment β of the absorbance due to dirt. Since there are two equations obtained by changing the optical path length l for two unknowns, the component concentration c can be obtained by the following equation (f12) based on the equations (f10) and (f11). Then, the increment β'' of the absorbance due to the contamination in the first optical path can be obtained by the following equation (f13). By multiplying the increment β'' of the absorbance due to dirt in the first optical path by the coefficient γ, the increment of the absorbance due to dirt in the second optical path can be obtained.
c = (A1-A2) / {(1-a) × e × l} ... (f12)
β'' = (A2-a × A1) / {γ × (1-a)} ・ ・ ・ (f13)

As described above, according to the method (3) above, even if the light transmission length and the light scattering behavior of the portion where the dirt is attached are different for each optical path, the component concentration c and the absorbance due to the dirt in the first optical path are increased. β'' and the increment of absorbance due to dirt in the second optical path γ × β'' can be obtained.

(4) In some embodiments, in any of the methods (1) to (3), the first absorbance calculated in the first absorbance calculation step and the second absorbance calculated in the second absorbance calculation step. (2) A stain degree calculation step of calculating the stain degree of the optical member in contact with the liquid based on the absorbance is further provided.

According to the method (4) above, for example, when dirt adheres to the light transmitting portion irradiated from the irradiation unit in the spectroscopic analyzer, the increase in absorbance due to the dirt can be obtained.

(5) The spectroscopic analyzer according to at least one embodiment of the present invention is
The liquid distribution department where the liquid to be analyzed can be distributed,
An irradiation unit that irradiates the liquid flowing through the liquid distribution unit with light from a light source from the outside of the liquid distribution unit.
A reflecting unit that reflects light that is irradiated from the irradiation unit and transmitted through the liquid,
A light receiving unit that receives the light reflected by the reflecting unit outside the liquid flow unit, and a light receiving unit.
With
The irradiation unit includes a light guide mirror that reflects light from the light source and guides it to the liquid flow unit, and a change unit that changes at least one of the positions and angles of the light guide mirror.

According to the configuration of (5) above, the optical path length l of the light passing through the liquid to be analyzed can be changed by changing at least one of the position and the angle of the light guide mirror. Therefore, according to the configuration of (5) above, the optical path length I of each light received by the light receiving unit can be measured by changing the optical path length of the light passing through the liquid to be analyzed. The first absorbance A1 before the change and the second absorbance A2 after the change in the optical path length l can be obtained. Here, since the change multiple a of the optical path length l and the optical path length l are preset values and the molar extinction coefficient e is known because of the physical property value, the unknown is the increment of the absorbance due to the component concentration c and dirt. There are two β. Since there are two equations obtained by changing the optical path length l for two unknowns, the component concentration c is determined by the above equation (f4) based on the above equations (f2) and (f3). It can be obtained, and the incremental β of the absorbance due to contamination can be obtained by the above equation (f5).

As described above, according to the configuration of (5) above, the component concentration c can be obtained even when the light transmitting portion irradiated from the irradiation portion is contaminated. Further, according to the configuration of (5) above, when dirt adheres to the light transmitting portion irradiated from the irradiation unit, the increment β of the absorbance due to the dirt can be obtained. Therefore, according to the configuration of (5) above, the correct component concentration c can be measured even when it is difficult to frequently perform maintenance of the liquid distribution section.

Further, according to the configuration of (5) above, since the light from the light source is reflected by the light guide mirror and guided to the liquid flow portion, the optical member on the light source side of the light guide mirror and the light guide mirror can be used. It can be separated from the liquid flow section. For example, as will be described later, when the liquid to be analyzed contains a radioactive substance, when the light guide mirror and the optical member on the light source side of the light guide mirror are made of a material susceptible to radiation such as quartz, for example. By separating the light guide mirror and the optical member on the light source side of the light guide mirror from the liquid flow portion, it is possible to make it less susceptible to the influence of radiation.

(6) In some embodiments, in the configuration of (5) above,
A measuring unit that measures the intensity of the light received by the light receiving unit before and after changing at least one of the positions or angles of the light guide mirror by the changing unit.
The first absorbance before changing at least one of the position or angle of the light guide mirror by the changing unit based on the intensity measured by the measuring unit and the intensity of light emitted from the irradiation unit. And the absorbance calculation unit that calculates the second absorbance after changing at least one of the position or angle of the light guide mirror by the change unit.
A concentration calculation unit that calculates the concentration of the component to be analyzed in the liquid based on the first absorbance and the second absorbance calculated by the absorbance calculation unit.
Further prepare.

According to the configuration of (6) above, the optical path length of the light passing through the liquid to be analyzed can be changed, and the intensity I of each light received by the light receiving unit can be measured by the above-mentioned measuring unit. According to the configuration of (6) above, the first absorbance A1 before the change of the optical path length l and the second absorbance A2 after the change of the optical path length l can be obtained by the above-mentioned absorbance calculation unit. According to the configuration of (6) above, the component concentration c can be obtained by the concentration calculation unit described above.

(7) In some embodiments, in the configuration of (5) or (6) above, the changing portion reflects the reflection before and after changing at least one of the positions or angles of the light guide mirror. At least one of the position and the angle of the light guide mirror is changed so that the position where the light from the light source is irradiated is not changed in the unit.

For example, when the dirt on the reflecting part differs depending on the location, that is, when the dirting is uneven, the intensity of the reflected light, that is, the intensity of the light received by the light receiving part when the position where the light from the light source is irradiated in the reflecting part changes May change, and the calculation accuracy of the component concentration c may decrease.
According to the configuration of (7) above, the position where the light from the light source is irradiated in the reflecting portion is not changed before and after changing at least one of the position or the angle of the light guide mirror. Even if the degree of contamination differs depending on the location, it is possible to suppress a decrease in the calculation accuracy of the component concentration c.
The above configuration (7) is effective when it is difficult to frequently perform maintenance on the liquid distribution section and the reflective section cannot be frequently cleaned.

(8) In some embodiments, in any of the configurations (5) to (7) above, the irradiation unit uses the light from the light source as collimated light or as light focused at the reflection unit. Irradiate the liquid flowing through the liquid distribution unit.

According to the configuration (8) above, it is possible to suppress a decrease in the intensity of the light received by the light receiving unit, so that it is possible to suppress a decrease in the calculation accuracy of the component concentration c.

(9) In some embodiments, in any of the configurations (5) to (8) above, the liquid contains a radioactive substance.

When the liquid to be analyzed contains radioactive substances, it is desired to reduce the chances of workers being exposed to radiation, so it is difficult to frequently perform maintenance on the liquid distribution section.
In that respect, according to the configuration of (9) above, since it has the configuration of (5) described above, it is difficult to frequently perform maintenance of the liquid distribution section as in the case where the liquid to be analyzed contains a radioactive substance. Even in some cases, the correct concentration can be measured.

(10) In some embodiments, in the configuration of (9) above,
A housing having the liquid distribution unit and
A window plate that covers the opening formed in the housing to partition the inside and the outside of the liquid flow portion and transmits the light emitted from the irradiation portion and the light reflected by the reflection portion.
A sealing member that seals the gap between the housing and the window plate,
Further prepare.

According to the configuration of (10) above, the light from the irradiation unit can be incidented on the liquid to be analyzed through the window plate, and the light transmitted through the liquid through the window plate can be received by the light receiving unit. Therefore, according to the configuration (10) above, it is possible to prevent the liquid containing the radioactive substance from coming into contact with the irradiation unit and the light receiving unit.

(11) In some embodiments, in the configuration of (10) above, the window plate is made of aluminum oxide.

For example, if the window plate is made of quartz, if the window plate is exposed to radiation from a liquid containing a radioactive substance, the transparency of the window plate will decrease in a relatively short period of time. However, if the window plate is made of aluminum oxide, the transparency of the window plate is unlikely to decrease even if the window plate is exposed to radiation from a liquid containing a radioactive substance.
Therefore, according to the configuration (11) above, the transparency of the window plate is unlikely to decrease, so that the frequency of replacement of the window plate can be suppressed and the cost increase can be suppressed.

(12) In some embodiments, in the configuration of (10) or (11) above, the sealing member is made of metal.

For example, if the sealing member is made of a polymer material, the sealing member deteriorates in a relatively short period of time when the sealing member is exposed to radiation from a liquid containing a radioactive substance. However, if the seal member is made of metal, the seal member is unlikely to deteriorate even if the seal member is exposed to radiation from a liquid containing a radioactive substance.
Therefore, according to the configuration (12) above, the seal member is less likely to deteriorate, so that the frequency of replacement of the seal member can be suppressed and the cost increase can be suppressed.

(13) In some embodiments, in any of the configurations (9) to (12) above, the reflective section is arranged inside the liquid flow section and is made of metal.

According to the configuration of (13) above, since the reflective portion is arranged inside the liquid flow portion, it comes into direct contact with the liquid containing a radioactive substance. Therefore, for example, when quartz glass is used for the reflecting portion, the transparency of the glass decreases in a relatively short period of time as described above, and the reflectance of light at the reflecting portion is relatively short. It will drop at.
However, according to the configuration of (13) above, since the reflecting portion is made of metal, it is possible to suppress a decrease in the reflectance of light at the reflecting portion.

According to at least one embodiment of the present invention, the spectroscopic analyzer can measure the correct concentration even when it is difficult to frequently maintain the measuring probe.

It is a figure which shows an example of the usage form of the spectroscopic analyzer of some embodiments schematically. It is sectional drawing which shows typically the structure of the measurement probe of some embodiments. It is sectional drawing which shows typically the structure of the measurement probe of another embodiment. It is sectional drawing which shows typically the structure of the measurement probe of still another embodiment. It is sectional drawing which shows typically the structure of the measurement probe of still another embodiment. It is a flowchart which showed the processing procedure in the spectroscopic analysis method by the spectroscopic analyzer which concerns on some Embodiments. It is a figure for demonstrating an example of a modification of the structure of a measurement probe. It is a figure for demonstrating an example of a modification of the structure of a measurement probe. It is a figure for demonstrating another example of the modification of the structure of a measurement probe. It is a figure for demonstrating another example of the modification of the structure of a measurement probe. It is a figure for demonstrating an example of the modification about the structure for changing the optical path length. It is a figure for demonstrating an example of the modification about the structure for changing the optical path length.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present invention to this, but are merely explanatory examples. Absent.
For example, expressions that represent relative or absolute arrangements such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric" or "coaxial" are exact. Not only does it represent such an arrangement, but it also represents a state of relative displacement with tolerances or angles and distances to the extent that the same function can be obtained.
For example, expressions such as "same", "equal", and "homogeneous" that indicate that things are in the same state not only represent exactly the same state, but also have tolerances or differences to the extent that the same function can be obtained. It shall also represent the state of existence.
For example, an expression representing a shape such as a quadrangular shape or a cylindrical shape not only represents a shape such as a quadrangular shape or a cylindrical shape in a geometrically strict sense, but also an uneven portion or chamfering within a range in which the same effect can be obtained. The shape including the part and the like shall also be represented.
On the other hand, the expressions "equipped", "equipped", "equipped", "included", or "have" one component are not exclusive expressions that exclude the existence of other components.

FIG. 1 is a diagram schematically showing an example of usage of the spectroscopic analyzer of some embodiments. The spectroscopic analyzer 1 of some embodiments is a so-called probe-type spectroscopic analyzer, and the analyzer main body 10 and the measurement probe 100 are connected by an optical fiber cable 20.
The spectroscopic analyzer 1 of some embodiments is for measuring the concentration of radioactive substances such as uranium and plutonium in the liquid inside pipes and towers online in a nuclear facility such as a nuclear fuel reprocessing plant. It may be used for.
Hereinafter, a case where the concentration of radioactive substances such as uranium and plutonium in the liquid inside pipes and tower tanks is measured online will be described by using the spectroscopic analyzer 1 of some embodiments in the nuclear facility as described above. ..

Of the spectroscopic analyzer 1, the measurement probe 100 is attached to pipes and tower tanks in a nuclear facility in a high dose area 91 having a relatively high air dose rate. In the example shown in FIG. 1, the measurement probe 100 is attached to a pipe 80 through which a liquid containing a radioactive substance such as uranium or plutonium flows in a nuclear facility.
Of the spectroscopic analyzer 1, the analyzer main body 10 is installed in the low dose area 92, which has a lower air dose rate than the high dose area 91. Specifically, the analyzer main body 10 is installed in a control room or the like. In some embodiments, the high dose area 91 and the low dose area 92 are separated by a wall portion 93.

(Analyzer body 10)
In some embodiments, the analyzer body 10 includes a light source 11, a spectroscope 12, a detector 13, and a control device 14 in a housing. Since the light source 11, the spectroscope 12, and the detector 13 have known configurations as spectroscopic analyzers, description thereof will be omitted. The details of the control device 14 will be described later.

(Optical fiber cable 20)
In some embodiments, the analyzer body 10 and the measurement probe 100, which are installed at distant locations from each other, are connected by a plurality of optical fiber cables 20 as described above. As shown in FIG. 1, the optical fiber cable 20 may be laid through, for example, a wall portion 93 that partitions the high-dose area 91.
In some embodiments, the measuring probe 100 and the analyzer main body 10 are an irradiation optical fiber cable 20a that guides the light from the light source 11 to the measuring probe 100, and a detector that detects the light from the measuring probe 100. It is connected to, for example, three light receiving optical fiber cables 20b leading to 13.
The measurement probe 100 of one embodiment shown in FIG. 9 and the analyzer main body 10 disperse the light from one irradiation optical fiber cable 20a that guides the light from the light source 11 to the measurement probe 100 and the light from the measurement probe 100. It is connected to one light receiving optical fiber cable 20b leading to the vessel 12.

The optical fiber cable 20 may be configured so that it can be connected to and disconnected from the analyzer main body 10 via a connector (not shown). The optical fiber cable 20 may be provided integrally with the measurement probe 100, or may be configured so that it can be connected to and disconnected from the measurement probe 100 via a connector (not shown).

(Measurement probe 100)
FIG. 2 is a cross-sectional view schematically showing the configuration of the measurement probe 100 of some embodiments. In some embodiments, the measuring probe 100 has a housing 101 having a tubular tubular portion 103 and a flange portion 105 attached to the tubular portion 103.
In the measurement probe 100 of some embodiments shown in FIG. 2, a liquid flow section 110 through which the liquid to be analyzed flowing in the pipe 80 can flow is provided on the tip end side of the tubular section 103. That is, an opening 111 is formed on the tip end side of the tubular portion 103 for the liquid to be analyzed flowing in the pipe 80 to flow into the liquid flow section 110 and flow out from the liquid flow section 110.

A partition wall 107 is provided inside the tubular portion 103. Of the internal space of the housing 101, the space 109 above the partition wall 107 is partitioned from the liquid flow section 110 by the partition wall 107 and the window plate 115 described later. That is, in the measurement probe 100 of some embodiments, the partition wall 107 and the window plate 115 prevent the liquid flowing in the pipe 80 from entering the inside of the space 109.

In the measurement probe 100 of the embodiment shown in FIG. 2, the light guided from the light source 11 via the optical fiber cable 20a for irradiation is incident on the liquid flowing through the liquid flow unit 110 and transmitted through the liquid, and the liquid flow unit is transmitted. It is configured to be reflected by the reflecting surface 131 of the reflecting unit 130 arranged in the 110. Further, the measurement probe 100 of the embodiment shown in FIG. 2 receives light reflected by the reflecting surface 131 and further transmitted through the liquid flowing through the liquid flow unit 110, and is spectroscopically transmitted via the light receiving optical fiber cable 20b. It is configured to lead to the vessel 12.
Hereinafter, the configuration of the measurement probe 100 of the embodiment shown in FIG. 2 will be specifically described.

Inside the housing 101 (inside the space 109), an end surface 21a of the irradiation optical fiber cable 20a and an end surface 21b of the light receiving optical fiber cable 20b are arranged. Two light guide mirrors 30 are arranged inside the housing 101 (inside the space 109).
One of the two light guide mirrors 30 is an irradiation for reflecting the light from the light source 11 guided by the irradiation optical fiber cable 20a and emitted from the end face 21a toward the liquid flowing through the liquid flow unit 110. Light guide mirror 31.
The other of the two light guide mirrors 30 is a light receiving light guide mirror 32 for reflecting the light transmitted through the liquid flowing through the liquid flow unit 110 toward the end surface 21b of the light receiving optical fiber cable 20b.

In the embodiment shown in FIG. 2, the irradiation light guide mirror 31 is configured so that the angle, that is, the posture of the irradiation light guide mirror 31 can be changed. Specifically, the irradiation light guide mirror 31 is configured so that the angle is changed by the angle changing actuator 41 as shown by the arrow a in FIG. In the embodiment shown in FIG. 2 and FIGS. 3 to 5 described later, the irradiation optical fiber cable 20a and the light receiving optical fiber cable 20b are fixed to the housing 101 and are immovable. ..
When the angle of the irradiation light guide mirror 31 is changed by the angle changing actuator 41, the optical path of light from the irradiation light guide mirror 31 to the liquid flow unit 110 is, for example, the incident optical path shown by the solid line in FIG. It is changed from 311 to the incident optical path 313 shown by the broken line.
Further, when the angle of the irradiation light guide mirror 31 is changed by the angle changing actuator 41, the optical path of light from the liquid flow unit 110 to the light receiving light guide mirror 32 is shown by a solid line in FIG. 2, for example. The reflected light path 321 is changed to the reflected light path 323 indicated by a broken line.

When the angle of the light guide mirror 31 for irradiation is changed by the angle changing actuator 41, the incident angle of the light incident on the liquid flowing through the liquid distribution unit 110 is changed. As a result, the optical path length l from the window plate 115 to the reflection unit 130 in the liquid flow unit 110 and the optical path length l from the reflection unit 130 to the window plate 115 of the light reflected by the reflection unit 130 are changed. That is, when the angle of the irradiation light guide mirror 31 is changed, the optical path length l of the light transmitted through the liquid in the liquid flow unit 110 changes.
In the embodiment shown in FIG. 2, when the angle of the irradiation light guide mirror 31 is changed, the position Pr where the light from the light source 11 is irradiated in the reflecting unit 130 is changed.

In the embodiment shown in FIG. 2, the light receiving light guide mirror 32 is configured so that the angle, that is, the posture of the light receiving light guide mirror 32 can be changed. Specifically, the light receiving light guide mirror 32 is configured so that the angle is changed by the angle changing actuator 42 as shown by the arrow b in FIG. By changing the angle of the light receiving light guide mirror 32 by the angle changing actuator 42, the angle of the irradiation light guide mirror 31 is changed as described above, and the light from the light source 11 is irradiated in the reflecting unit 130. Even if the position is changed, the light from the reflecting unit 130 can be incident on the end surface 21b of the light receiving optical fiber cable 20b.

In the embodiment shown in FIG. 2, the angle change of the irradiation light guide mirror 31 and the light receiving light guide mirror 32 by the angle changing actuators 41 and 42 is controlled by the control device 14.

In the embodiment shown in FIG. 2, an opening 107a is formed in the partition wall 107 so that the light from the light source 11 can pass through the inside and outside of the liquid flow unit 110. The opening 107a is covered with a transparent window plate 115. That is, the window plate 115 covers the opening 107a, which is an opening formed in the housing 101 (partition wall 107), to partition the inside and the outside of the liquid flow unit 110, and the light emitted from the irradiation unit 3 described later. , And the light reflected by the reflecting unit 130 is transmitted.
A seal member 117 for sealing the gap between the partition wall 107 and the window plate 115 is arranged between the partition wall 107 and the window plate 115.
Therefore, the light from the irradiation light guide mirror 31 can reach the liquid flowing through the liquid flow unit 110 through the window plate 115. Further, the light reflected by the reflecting unit 130 can pass through the window plate 115 and reach the light receiving light guide mirror 32. That is, in the embodiment shown in FIG. 2, the light from the irradiation unit 3 can be incidented on the liquid to be analyzed through the window plate 115, and the light transmitted through the liquid through the window plate 115 is received as described later. The light can be received by the unit 5. Therefore, according to the embodiment shown in FIG. 2, it is possible to prevent the liquid containing the radioactive substance from coming into contact with the irradiation unit 3 and the light receiving unit 5.

In the embodiment shown in FIG. 2, the window plate 115 is made of aluminum oxide.
For example, if the window plate 115 is made of quartz, if the window plate 115 is exposed to radiation from a liquid containing a radioactive substance, the transparency of the window plate 115 will decrease in a relatively short period of time. However, if the window plate 115 is made of aluminum oxide, the transparency of the window plate 115 is unlikely to decrease even if the window plate 115 is exposed to radiation from a liquid containing a radioactive substance.
Therefore, according to the embodiment shown in FIG. 2, the transparency of the window plate 115 is unlikely to decrease, so that the frequency of replacement of the window plate 115 can be suppressed and the cost increase can be suppressed.

In the embodiment shown in FIG. 2, the seal member 117 is made of metal.

For example, if the sealing member 117 is made of a polymer material, if the sealing member 117 is exposed to radiation from a liquid containing a radioactive substance, the sealing member 117 deteriorates in a relatively short period of time. However, if the seal member 117 is made of metal, the seal member 117 is unlikely to deteriorate even if the seal member 117 is exposed to radiation from a liquid containing a radioactive substance.
Therefore, according to the embodiment shown in FIG. 2, since the seal member 117 is less likely to deteriorate, the frequency of replacement of the seal member 117 can be suppressed and the cost increase can be suppressed.

In the embodiment shown in FIG. 2, a reflecting portion 130 that reflects light from the light source 11 is arranged inside the tip side of the tubular portion 103, that is, inside the lower side in FIG. In the embodiment shown in FIG. 2, it is arranged inside the liquid distribution unit 110. In the embodiment shown in FIG. 2, the reflecting portion 130 is a metal concave mirror.
In the embodiment shown in FIG. 2, since the reflection unit 130 is arranged inside the liquid flow unit 110, it comes into direct contact with the liquid containing a radioactive substance. Therefore, for example, when quartz glass is used for the reflecting portion 130, the transparency of the glass decreases in a relatively short period of time as described above, and the reflectance of light at the reflecting portion 130 is compared. It will decrease in a short period of time.
However, according to the embodiment shown in FIG. 2, since the reflecting portion 130 is made of metal, it is possible to suppress a decrease in the reflectance of light in the reflecting portion 130.

In the embodiment shown in FIG. 2, even if the angle of the irradiation light guide mirror 31 is changed and the position Pr where the light from the light source 11 is irradiated is changed, the light from the light source 11 is received as a light receiving guide. The shape of the reflecting surface 131 of the reflecting portion 130 has a pre-designed shape so that it can be reflected toward the mirror 32.

In some embodiments, the spectroscopic analyzer 1 includes an irradiation unit 3 that irradiates the liquid flowing through the liquid flow unit 110 from the outside of the liquid flow unit 110 with light from the light source 11, and a liquid that is irradiated from the irradiation unit 3. It includes a reflecting unit 130 that reflects the light transmitted through the liquid, and a light receiving unit 5 that receives the light reflected by the reflecting unit 130 outside the liquid flow unit 110.

In some embodiments, the irradiation unit 3 includes a light source 11, a light guide mirror 30 (light guide mirror 31 for irradiation) that reflects light from the light source 11 and guides the light to the liquid flow unit 110, and a light guide mirror for irradiation. It has a changing unit 40 for changing the angle of 31. In some embodiments, the changing section 40 includes an angle changing actuator 41.

In some embodiments, the light receiving section 5 comprises a spectroscope 12, a light receiving light guide mirror 32 for reflecting the light reflected by the reflecting section 130 toward the end face 21b of the light receiving optical fiber cable 20b, and the like. It has a changing unit 40 for changing the angle of the light receiving light guide mirror 32. In some embodiments, the changing section 40 includes an angle changing actuator 42.

In some embodiments, the spectroscopic analyzer 1 includes a measurement unit 17, an absorbance calculation unit 141, and a concentration calculation unit 143. Further, in some embodiments, the spectroscopic analyzer 1 includes a stain degree calculation unit 145.
In some embodiments, the measuring unit 17 measures the intensity of the light received by the light receiving unit 5 before and after the angle of the light guide mirror 30 is changed by the changing unit 40. That is, in some embodiments, the measuring unit 17 corresponds to the detector 13.

In some embodiments, the absorbance calculation unit 141, the concentration calculation unit 143, and the stain degree calculation unit 145 are included as functional blocks of the control device 14.

In some embodiments, the absorbance calculation unit 141 determines the angle of the light guide mirror 30 by the change unit 40 based on the intensity of the light measured by the measurement unit 17 and the intensity of the light emitted from the irradiation unit 3. The first absorbance A1 before changing the above value and the second absorbance A2 after changing the angle of the light guide mirror 30 by the changing unit 40 are calculated.
In some embodiments, the concentration calculation unit 143 is in the liquid flowing through the liquid flow unit 110, as will be described later, based on the first absorbance A1 and the second absorbance A2 calculated by the absorbance calculation unit 141. The concentration of the component to be analyzed (component concentration c) is calculated.
Further, in some embodiments, the dirtiness calculation unit 145 is based on the first absorbance A1 and the second absorbance A2 calculated by the absorbance calculation unit 141, and as will be described later, the window plate 115 and the reflection unit. The incremental β of the absorbance due to the stain of 130 is calculated.

(About calculation of component concentration c and incremental β of absorbance due to dirt)
Hereinafter, the calculation of the component concentration c and the incremental β of the absorbance due to stains will be described.
The concentration of the solution component having the absorption property can be quantified according to Lambert-Beer's law shown in the following formula (f1). From the formula (f1), the absorbance (A) can be obtained from the molar extinction coefficient (e), the component concentration (c), and the optical path length (l). If the molar extinction coefficient e and the optical path length l are known, the absorbance The component concentration c can be obtained by measuring A.
A = -log (I / I ₀ )
= E × c × l ・ ・ ・ (f1)
Here, I ₀ is the incident light, that is, the intensity of the light emitted from the irradiation unit 3. I is the intensity of the transmitted light, that is, the light transmitted through the liquid flowing through the liquid flowing section 110 and received by the light receiving section 5. Here, in order to simplify the explanation, the light attenuation in the light guide path from the light source 11 in the irradiation unit 3 to the liquid flowing through the liquid flow unit 110, and the liquid flowing through the liquid flow unit 110 The attenuation of the light in the light guide path until the light transmitted through the light source reaches the spectroscope 12 of the light receiving unit 5 is ignored.
Absorbance A is a dimensionless value. The unit of the molar extinction coefficient e is [mol / L / m]. The unit of the component concentration c is [mol / L]. The unit of the optical path length l is [m].

Here, if dirt is attached to the light transmitting portion emitted from the irradiation unit 3, that is, the window plate 115 or the reflecting portion 130, the light is also absorbed by the dirt, so that the absorbance (A') is high. , Increment in absorbance (β) due to dirt is added and expressed by the formula (f2).
A'= e × c × l + β ・ ・ ・ (f2)

When the window plate 115 or the reflecting unit 130 is not dirty, the intensity of the light emitted from the irradiation unit 3 (incident light intensity I ₀ ) and the intensity of the light received by the light receiving unit 5 (transmitted light intensity I). ), The molar extinction coefficient e, and the optical path length l, the component concentration c can be obtained based on the formula (f1).
However, when dirt is attached to the window plate 115 or the reflective portion 130, the calculated absorbance A'contains the absorbance β due to the dirt, so there are two unknowns (β and c) for one equation. ), Therefore, the component concentration c cannot be obtained as it is.

Therefore, if two equations are obtained by measuring the absorbance A by changing the optical path length l, the component concentration c can be obtained by combining these two equations, and the absorbance increment β due to dirt can be obtained. Can also be asked.
From the formula (f1), when the molar extinction coefficient e and the component concentration c are constant, when the optical path length l is lengthened, the absorbance A also increases in proportion to the optical path length l. The absorbance (A ″) when the optical path length l is multiplied by a is expressed by the following equation (f3).
A'' = a × e × c × l + β ・ ・ ・ (f3)

In the spectroscopic analyzer 1 according to some of the above-described embodiments, the optical path length l of light passing through the liquid flowing through the liquid distribution unit 110 is changed by changing at least one of the positions or angles of the light guide mirror 30. Can be changed. In the embodiment shown in FIG. 2, the optical path length l of the light passing through the liquid flowing through the liquid distribution unit 110 can be changed by changing the angle of the light guide mirror 30.

Therefore, in the embodiment shown in FIG. 2, the optical path length l of the light passing through the liquid flowing through the liquid distribution unit 110 is changed by changing the angle of the light guide mirror 30, and the light receiving unit 5 receives the light. The light intensity I is measured.
For example, in the embodiment shown in FIG. 2, the control device 14 controls the angle changing actuators 41 and 42 to change the angles of the irradiation light guide mirror 31 and the light receiving light guide mirror 32. Then, in the embodiment shown in FIG. 2, the measuring unit 17 receives the light received by the light receiving unit 5 before and after changing the angles of the irradiation light guide mirror 31 and the light receiving light guide mirror 32. Measure the strength.
Then, the absorbance calculation unit 141 obtains the first absorbance A1 before the change of the optical path length l and the second absorbance A2 after the change of the optical path length l.

Here, since the change multiple a of the optical path length l and the optical path length l are preset values and the molar extinction coefficient e is known because of the physical property value, the unknown is the increment of the absorbance due to the component concentration c and dirt. There are two β. Since there are two equations obtained by changing the optical path length l for two unknowns, the component concentration c can be obtained by the following equation (f4) based on the equations (f2) and (f3). Then, the increment β of the absorbance due to dirt can be obtained by the following equation (f5).
Therefore, in the embodiment shown in FIG. 2, the concentration calculation unit 143 obtains the component concentration c by the following equation (f4). Further, in the embodiment shown in FIG. 2, the stain degree calculation unit 145 obtains the increment β of the absorbance due to the stain by the following equation (f5).
c = (A2-A1) / {e × l × (a-1)} ・ ・ ・ (f4)
β = (a × A1-A2) / (a-1) ... (f5)

As described above, according to the spectroscopic analyzer 1 according to some of the above-described embodiments, the window plate 115 or the reflecting portion 130, which is the transmitting portion of the light emitted from the irradiation unit 3, is contaminated. Also, the component concentration c can be obtained. Further, according to the spectroscopic analyzer 1 according to some of the above-described embodiments, when dirt adheres to the window plate 115 or the reflecting portion 130, the increment β of the absorbance due to the dirt can be obtained. Therefore, according to the spectroscopic analyzer 1 according to some of the above-described embodiments, there is a distance reason such as the installation location of the measurement probe 100 is far away, and accessibility such as the installation location of the measurement probe 100 is narrow. Frequent maintenance of the liquid flow unit 110 is performed because there are reasons why it is not easy to remove the measurement probe 100 from the pipe 80, etc. Even if it is difficult to do so, the correct component concentration c can be measured.

Further, according to the spectroscopic analyzer 1 according to some of the above-described embodiments, the light from the light source 11 is reflected by the light guide mirror 30 and guided to the liquid flow unit 110, so that the light guide mirror for irradiation is used. The optical member on the light source 11 side of the 31 and the irradiation light guide mirror 31 and the optical member on the spectroscope 12 side of the light receiving light guide mirror 32 and the light receiving light guide mirror 32 can be separated from the liquid flow unit 110. ..

In the spectroscopic analyzer 1 according to some of the above-described embodiments, the optical member on the light source 11 side of the irradiation light guide mirror 31 includes, for example, an irradiation optical fiber cable 20a. In the following description, the optical member on the light source 11 side of the irradiation light guide mirror 31 and the irradiation light guide mirror 31 is also simply referred to as a light source side optical member.
Further, in the spectroscopic analyzer 1 according to some of the above-described embodiments, the optical member on the spectroscope 12 side of the light receiving light guide mirror 32 includes, for example, a light receiving optical fiber cable 20b. In the following description, the optical member on the spectroscope 12 side of the light receiving light guide mirror 32 and the light receiving light guide mirror 32 is also simply referred to as a spectroscope side optical member.

For example, as described above, when the liquid flowing through the liquid flow unit 110 contains a radioactive substance, when a material susceptible to radiation such as quartz is used for the light source side optical member and the spectroscope side optical member, for example. By separating the light source side optical member and the spectroscope side optical member from the liquid flow unit 110, it is possible to make them less susceptible to the influence of radiation.

As described above, when the measurement probe 100 is arranged in the high dose area 91 having a relatively high air dose rate, or when the liquid flowing through the liquid distribution unit 110 contains radioactive substances, the worker is exposed to radiation. It is difficult to frequently perform maintenance on the liquid distribution unit 110 because it is desired to reduce the chances of doing so.
In that respect, according to the spectroscopic analyzer 1 according to some of the above-described embodiments, even if the liquid flow unit 110 cannot be maintained and the window plate 115 or the reflection unit 130 becomes dirty, the correct concentration can be measured. ..

According to the spectroscopic analyzer 1 according to some of the above-described embodiments, the optical path length l of the light passing through the liquid flowing through the liquid distribution unit 110 is changed to change the intensity I of each light received by the light receiving unit 5. It can be measured by the measurement unit 17 described above. According to the spectroscopic analyzer 1 according to some of the above-described embodiments, the first absorbance A1 before the change of the optical path length l and the second absorbance A2 after the change of the optical path length l are obtained by the above-mentioned absorbance calculation unit 141. You can ask. According to the spectroscopic analyzer 1 according to some of the above-described embodiments, the component concentration c can be obtained by the above-mentioned concentration calculation unit 143.

In the spectroscopic analyzer 1 according to some of the above-described embodiments, the irradiation unit 3 irradiates the liquid flowing through the liquid flow unit 110 with the light from the light source 11 as collimated light or as the light focused by the reflection unit 130. It may be configured to do so.
Specifically, for example, the irradiation light guide mirror 31 may be a collimator mirror. Then, the irradiation light guide mirror 31 irradiates the liquid flowing through the liquid flow unit 110 with the light emitted from the end surface 21a of the irradiation optical fiber cable 20a as collimated light or as light focused by the reflection unit 130. It may be configured as follows.
As a result, it is possible to suppress a decrease in the intensity of the light received by the light receiving unit 5, so that a decrease in the calculation accuracy of the component concentration c can be suppressed.

FIG. 3 is a cross-sectional view schematically showing the configuration of the measurement probe 100 of another embodiment. The same configurations as those of the embodiment shown in FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted.
In the other embodiment shown in FIG. 3, in addition to the configuration according to the embodiment shown in FIG. 2, the position of the reflection unit 130A can be changed. Specifically, the reflecting unit 130A is configured such that the position changing actuator 43 changes the separation distance from the window plate 115 facing the liquid flow unit 110 as shown by the arrow c in FIG. Has been done. That is, in another embodiment shown in FIG. 3, the reflection unit 130A is configured so that the distance between the irradiation light guide mirror 31 and the light receiving light guide mirror 32 can be changed. In the other embodiment shown in FIG. 3, the reflecting unit 130A may be a planar mirror. The position change actuator 43 is included in the change unit 40.

When the position of the reflection unit 130A is changed by the position change actuator 43 and the angle of the irradiation light guide mirror 31 is changed by the angle change actuator 41, the irradiation light guide mirror 31 is transferred to the liquid flow unit 110. The optical path of the heading light is changed from, for example, the incident optical path 311A shown by the solid line in FIG. 3 to the incident optical path 313A shown by the broken line.
Here, by appropriately setting the movement amount of the reflection unit 130A and the angle change of the light guide mirror 31 for irradiation, even if the position of the reflection unit 130A is changed, the light from the light source 11 is irradiated by the reflection unit 130A. The position Pr can be prevented from being changed. However, since the position of the reflecting surface 131 itself moves as the position of the reflecting portion 130A is changed, the distance between the position Pr and the irradiation light guide mirror 31 and the light receiving light guide mirror 32 changes.

Further, when the position of the reflecting portion 130A is changed by the position changing actuator 43 and the angle of the irradiation light guide mirror 31 is changed by the angle changing actuator 41, the light receiving light guide mirror from the liquid flow unit 110 is changed. The optical path of light toward 32 is changed from, for example, the reflected light path 321A shown by the solid line in FIG. 3 to the reflected light path 323A shown by the broken line.
By changing the position of the reflecting portion 130A by the position changing actuator 43, the separation distance between the reflecting portion 130A and the window plate 115 is changed, so that the optical path length of the light transmitted through the liquid in the liquid flowing portion 110 is changed. l changes.

In the embodiment shown in FIG. 3, the control device 14 also controls the change in the position of the reflection unit 130A by the position change actuator 43.

Even if the optical path of the light from the liquid flow unit 110 to the light receiving light guide mirror 32 is changed as described above, the light path is reflected by changing the angle of the light receiving light guide mirror 32 by the angle changing actuator 42. The light from the portion 130A can be incident on the end surface 21b of the light receiving optical fiber cable 20b.

As described above, in the other embodiment shown in FIG. 3, in the changing unit 40, the position Pr where the light from the light source 11 is irradiated in the reflecting unit 130A before and after changing the angle of the light guide mirror 30 is set. The angle of the light guide mirror 30 can be changed so as not to be changed.

For example, when the reflection unit 130A is soiled differently depending on the location, that is, when the contamination is uneven, when the position where the light from the light source 11 is irradiated in the reflection unit 130A changes, the intensity of the reflected light, that is, the light receiving unit 5 receives light. The intensity of the light emitted may change, and the calculation accuracy of the component concentration c may decrease.
According to another embodiment shown in FIG. 3, since the position where the light from the light source 11 is irradiated in the reflecting portion 130A is not changed before and after changing the angle of the light guide mirror 30, the reflecting portion 130A Even if the degree of contamination differs depending on the location, it is possible to suppress a decrease in the calculation accuracy of the component concentration c.
The other embodiment shown in FIG. 3 is effective when it is difficult to frequently perform maintenance on the liquid distribution unit 110 and the reflective unit 130A cannot be frequently cleaned.

FIG. 4 is a cross-sectional view schematically showing the configuration of the measurement probe 100 of still another embodiment. The same configurations as those of the embodiment shown in FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted.
The embodiment shown in FIG. 4 is different from the configuration according to the embodiment shown in FIG. 2 in that the positions of the two light guide mirrors 30 are movable rather than the angles. Specifically, the irradiation light guide mirror 31 is configured so that the position is changed by the position changing actuator 44 as shown by the arrow d in FIG.

In the embodiment shown in FIG. 4, the reflective portion 130B is a plane mirror, but the reflective surface 131 is a surface of the window plate 115 on the liquid flow portion 110 side, that is, a liquid contact surface 115a in contact with the liquid flowing through the liquid flow portion 110. It is inclined with respect to. Therefore, in the embodiment shown in FIG. 4, the light from the light source 11 is irradiated in the reflection unit 130B without changing the angle of incidence of the light on the reflection unit 130B and the reflection angle of the light from the reflection unit 130B. By changing the position Pr, the optical path length l of the light transmitted through the liquid in the liquid flow unit 110 can be changed.

In the embodiment shown in FIG. 4, the moving direction of the irradiation light guide mirror 31 will be described. In the embodiment shown in FIG. 4, the moving direction of the irradiation light guide mirror 31 is changed when the irradiation light guide mirror 31 is moved to change the position Pr where the light from the light source 11 is irradiated in the reflection unit 130B. The optical path length l from the window plate 115 to the reflection unit 130 in the liquid flow unit 110 may be changed. An example of this direction is a direction parallel to the direction of the vector NA obtained by decomposing the normal vector N of the reflecting surface 131 in the same direction as the extending direction of the wetted surface 115a of the window plate 115.

In the embodiment shown in FIG. 4, the moving direction of the irradiation light guide mirror 31 is preferably parallel to the optical axis direction of the light emitted from the end surface 21a of the irradiation optical fiber cable 20a. If the moving direction of the irradiation light guide mirror 31 is parallel to the optical axis direction of the light emitted from the end surface 21a of the irradiation optical fiber cable 20a, the light is emitted from the end surface 21a even if the irradiation light guide mirror 31 is moved. This is because the light does not deviate from the light guide mirror 31 for irradiation.
The position of the end face 21a of the irradiation optical fiber cable 20a may be moved together with the irradiation light guide mirror 31.

When the position of the irradiation light guide mirror 31 is changed by the position change actuator 44, the optical path of light from the irradiation light guide mirror 31 to the liquid flow unit 110 is, for example, the incident optical path shown by the solid line in FIG. It is changed from 311B to the incident optical path 313B shown by the broken line.
Further, when the position of the irradiation light guide mirror 31 is changed by the position change actuator 44, the optical path of light from the liquid flow unit 110 to the light receiving light guide mirror 32 is shown by a solid line in FIG. 4, for example. The reflected light path 321B is changed to the reflected light path 323B shown by the broken line.

In the embodiment shown in FIG. 4, the light receiving light guide mirror 32 is configured so that the position of the light receiving light guide mirror 32 is changed by the position changing actuator 45 as shown by the arrow e in FIG. By changing the position of the light receiving light guide mirror 32 by the position changing actuator 45, the position of the irradiation light guide mirror 31 is changed as described above, and the light from the light source 11 is irradiated in the reflection unit 130B. Even if the position Pr is changed, the light from the reflecting portion 130B can be incident on the end surface 21b of the light receiving optical fiber cable 20b.

In the embodiment shown in FIG. 4, the position change of the irradiation light guide mirror 31 and the light receiving light guide mirror 32 by the position change actuators 44 and 45 is controlled by the control device 14.

In the embodiment shown in FIG. 4, the irradiation unit 3 includes a light source 11, a light guide mirror 30 (light guide mirror 31 for irradiation) that reflects light from the light source 11 and guides the light to the liquid flow unit 110, and a guide for irradiation. It has a changing unit 40 that changes the position of the optical mirror 31. In the embodiment shown in FIG. 4, the changing unit 40 includes a position changing actuator 45.

FIG. 5 is a cross-sectional view schematically showing the configuration of the measurement probe 100 of still another embodiment. The same configurations as those of the embodiment shown in FIG. 2 or FIG. 4 are designated by the same reference numerals, and detailed description thereof will be omitted.
The embodiment shown in FIG. 5 is different from the configuration according to the embodiment shown in FIG. 2 in that the angles and positions of the two light guide mirrors 30 are movable. Specifically, the irradiation light guide mirror 31 is configured so that the angle is changed by the angle changing actuator 41 as shown by the arrow a in FIG. 5, and the position changing actuator 44 is used. As shown by the arrow d in FIG. 5, the position is changed.

As described above, as shown in FIGS. 2 to 5, in some embodiments, the changing unit 40 is configured to change at least one of the positions and angles of the light guide mirror 30 (irradiation light guide mirror 31). It should be done.

(About spectroscopic analysis method)
FIG. 6 is a flowchart showing a processing procedure in the spectroscopic analysis method by the spectroscopic analyzer according to some of the above-described embodiments. The process shown in FIG. 6 is executed by an arithmetic circuit (not shown) in the control device 14.
The spectroscopic analysis methods according to some embodiments shown in FIG. 6 include a first measurement step S10, a first absorbance calculation step S20, a second measurement step S30, a second absorbance calculation step S40, and a concentration calculation step. S50 and a stain degree calculation step S60 are provided.

(First measurement step S10)
The first measurement step S10 is a step of measuring the intensity of the light received by the light receiving unit 5 before the changing unit 40 changes at least one of the positions or angles of the light guide mirror 30.
For example, in the embodiment shown in FIG. 2, in the first measurement step S10, the control device 14 controls the angle changing actuator 41 so that the irradiation light guide mirror 31 has, for example, a preset angle. The angle changing actuator 42 is controlled so that the light receiving light guide mirror 32 has, for example, a preset angle.

For example, in the embodiment shown in FIG. 3, in the first measurement step S10, the control device 14 controls the position change actuator 43 so that the reflection unit 130A is in a preset position, for example, and is used for irradiation. The angle changing actuators 41 and 42 are controlled so that the light guide mirror 31 and the light receiving light guide mirror 32 have, for example, preset angles.

For example, in the embodiment shown in FIG. 4, in the first measurement step S10, the control device 14 controls the position change actuator 44 so that the irradiation light guide mirror 31 is in a preset position, for example. , The position change actuator 45 is controlled so that the light receiving light guide mirror 32 is at a preset position, for example.

For example, in the embodiment shown in FIG. 5, in the first measurement step S10, the control device 14 has an angle changing actuator 41 and a position so that the irradiation light guide mirror 31 has, for example, a preset angle and position. In addition to controlling the changing actuator 44, the angle changing actuator 42 and the position changing actuator 45 are controlled so that the light receiving light guide mirror 32 has, for example, a preset angle and position.

Then, the control device 14 is separated by the spectroscope 12 and acquires the intensity I of the light detected by the detector 13 (measurement unit 17). The light intensity I acquired here is the light intensity I before the change of the optical path length l.
That is, in the first measurement step S10, the intensity of the light passing through the liquid to be analyzed is measured when the optical path length l is the optical path length before the change (first optical path length).

(First Absorbance Calculation Step S20)
In the first absorbance calculation step S20, the position of the light guide mirror 30 or the position of the light guide mirror 30 is changed by the changing unit 40 based on the light intensity I measured in the first measuring step S10 and the light intensity I ₀ emitted from the irradiation unit. This is a step of calculating the first absorbance A1 before changing at least one of the angles.
In the first absorbance calculation step S20, the absorbance calculation unit 141 of the control device 14 has the light intensity I measured in the first measurement step S10, the molar extinction coefficient e, the optical path length l, and the intensity I _{0 of the} incident light. Based on the above, the first absorbance A1 is calculated from the above formula (f1).
The molar extinction coefficient e, the intensity I _{0 of the} incident light, and the optical path length l before changing at least one of the positions or angles of the light guide mirror 30 by the changing unit 40 are stored in advance (not shown). It is assumed that it is remembered in.
That is, in the first absorbance calculation step S20, the first absorbance A1 when the optical path length is the optical path length before the change (first optical path length) is calculated based on the intensity I measured in the first measurement step S10.

(Second measurement step S30)
The second measurement step S30 is a step of measuring the intensity of the light received by the light receiving unit 5 after changing at least one of the positions or angles of the light guide mirror 30 by the changing unit 40.
For example, in the embodiment shown in FIG. 2, in the second measurement step S30, the control device 14 has the irradiation light guide mirror 31 set in advance, for example, and is different from the angle set in the first measurement step S10. The angle changing actuator 41 is controlled so as to have an angle. Further, the control device 14 controls the angle changing actuator 42 so that the light receiving light guide mirror 32 is set in advance and has an angle different from the angle set in the first measurement step S10, for example.

For example, in the embodiment shown in FIG. 3, in the second measurement step S30, the control device 14 has the reflection unit 130A set in advance, for example, at a position different from the position set in the first measurement step S10. The position change actuator 43 is controlled in this way. Further, the control device 14 controls the angle changing actuator 41 so that the irradiation light guide mirror 31 is set in advance and has an angle different from the angle set in the first measurement step S10, for example. Further, the control device 14 also controls the angle changing actuator 42 so that the light receiving light guide mirror 32 is set in advance, for example, and has an angle different from the angle set in the first measurement step S10.

For example, in the embodiment shown in FIG. 4, in the second measurement step S30, the control device 14 is different from the position where the irradiation light guide mirror 31 is set in advance, for example, in the first measurement step S10. The position change actuator 44 is controlled so as to be in the position. Further, the control device 14 controls the position change actuator 45 so that the light receiving light guide mirror 32 is set in advance, for example, and is at a position different from the position set in the first measurement step S10.

For example, in the embodiment shown in FIG. 5, in the first measurement step S10, the control device 14 has the angle and position where the irradiation light guide mirror 31 is set in advance and is set in the first measurement step S10, for example. Controls the angle changing actuator 41 and the position changing actuator 44 so that they have different angles and positions. Further, the control device 14 changes the angle and position of the light receiving light guide mirror 32 so that the light receiving light guide mirror 32 has an angle and position different from the angle and position set in the first measurement step S10, for example. Controls the actuator 45.

Then, the control device 14 is separated by the spectroscope 12 and acquires the intensity I of the light detected by the detector 13 (measurement unit 17). The light intensity I acquired here is the light intensity I after changing the optical path length l.
That is, in the second measurement step S30, the intensity of the light passing through the liquid to be analyzed is measured when the optical path length l is the changed optical path length (second optical path length).

(Second Absorbance Calculation Step S40)
In the first absorbance calculation step S20, the position of the light guide mirror 30 or the position of the light guide mirror 30 is changed by the changing unit 40 based on the light intensity I measured in the second measuring step S30 and the light intensity I ₀ emitted from the irradiation unit. This is a step of calculating the second absorbance A2 after changing at least one of the angles.
In the second absorbance calculation step S40, the absorbance calculation unit 141 of the control device 14 determines the light intensity I measured in the second measurement step S30, the molar extinction coefficient e, the optical path length l, and the intensity I _{0 of the} incident light. Based on the above, the second absorbance A2 is calculated from the above formula (f1).
It is assumed that the optical path length l after changing at least one of the position or the angle of the light guide mirror 30 by the changing unit 40 is stored in advance in a storage unit (not shown).
That is, in the second absorbance calculation step S40, the second absorbance A2 when the optical path length l is the changed optical path length (second optical path length) is calculated based on the intensity I measured in the second measurement step S30. ..

(Concentration calculation step S50)
The concentration calculation step S50 is an analysis target in the liquid flowing through the liquid flow unit 110 based on the first absorbance A1 calculated in the first absorbance calculation step S20 and the second absorbance A2 calculated in the second absorbance calculation step S40. This is a step of calculating the concentration of a component.
In the concentration calculation step S50, the concentration calculation unit 143 of the control device 14 uses the first absorbance A1 calculated in the first absorbance calculation step S20, the second absorbance A2 calculated in the second absorbance calculation step S40, and the change unit 40. The component concentration c is obtained from the above equation (f4) based on the change multiple a of the optical path length l before and after changing at least one of the position or the angle of the light guide mirror 30.

(Dirty degree calculation step S60)
The dirtiness calculation step S60 is based on the first absorbance A1 calculated in the first absorbance calculation step S20 and the second absorbance A2 calculated in the second absorbance calculation step S40, and the dirtiness in the light passage path in the liquid flow unit 110 This is the process of calculating the degree.
In the stain degree calculation step S60, the stain degree calculation unit 145 of the control device 14 changes the first absorbance A1 calculated in the first absorbance calculation step S20 and the second absorbance A2 calculated in the second absorbance calculation step S40. Based on the change multiple a of the optical path length l before and after changing at least one of the positions or angles of the light guide mirror 30 by 40, the window plate 115 and the reflecting portion 130 are derived from the above equation (f5). Find the incremental β of the absorbance due to the stain.
It should be noted that the calculation of the incremental β of the absorbance due to the dirt on the window plate 115 and the reflective portion 130 in the dirt degree calculation step S60 does not have to be performed all the time, and is calculated periodically at intervals of, for example, several days. May be good.

According to the spectroscopic analysis method according to some embodiments, the optical path length l of the light passing through the liquid flowing through the liquid flow unit 110 is changed by changing at least one of the position or the angle of the light guide mirror 30. Therefore, since the absorbance can be obtained, the component concentration c can be obtained as described above even when the light transmitting portion or the reflecting portion irradiated from the irradiation unit 3 is contaminated. Further, according to the spectroscopic analysis method according to some embodiments, when dirt adheres to the light transmitting portion or the reflecting portion irradiated from the irradiation unit 3, the absorbance due to the dirt is increased as described above. β can be obtained. Therefore, according to the spectroscopic analysis method according to some embodiments, the correct component concentration c can be measured even when it is difficult to frequently perform maintenance on the liquid distribution unit 110.

(About a modified example of the configuration of the measurement probe 100)
Hereinafter, a modified example of the configuration of the measurement probe 100 will be described. 7 and 8 are diagrams for explaining an example of a modification of the configuration of the measurement probe 100. The same configurations as those of the embodiment shown in FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted.
In the modified examples shown in FIGS. 7 and 8, the first reflecting unit 151, which is a plane mirror arranged in the liquid flow unit 110, and the second reflecting unit 150 arranged in the space 109 above the partition wall 107 are It is provided. In the modified example shown in FIGS. 7 and 8, the first reflecting portion 151 is arranged at the same position as the reflecting portion 130A according to the embodiment shown in FIG. 2, for example. In the modified examples shown in FIGS. 7 and 8, the second reflecting portion 150 may be arranged on the window plate 115 in the space 109.

In the modified examples shown in FIGS. 7 and 8, as shown in FIG. 7, the light emitted from the irradiation optical fiber cable 20a is reflected once by the first reflecting unit 151, and then the light receiving optical fiber cable 20b is reflected. Incident in. On the other hand, when the optical path is changed by driving the irradiation light guide mirror 31 by the angle changing actuator 41, the light emitted from the irradiation optical fiber cable 20a is first reflected as shown in FIG. After being first reflected by the unit 151, it is reflected again by the second reflecting unit 150 toward the first reflecting unit 151. Then, the light emitted from the irradiation optical fiber cable 20a is reflected by the first reflecting unit 151 for the second time, then reflected by the light receiving light guide mirror 32 and incident on the light receiving optical fiber cable 20b.
In the modified examples shown in FIGS. 7 and 8, the optical path (also referred to as the first optical path) 331 shown in FIG. 7 and the optical path (also referred to as the second optical path) 332 shown in FIG. The optical path length in the liquid flow unit 110 can be significantly changed as compared with the form.

9 and 10 are diagrams for explaining another example of a modification of the configuration of the measurement probe 100. The same configurations as those of the embodiment shown in FIGS. 2 or 7 are designated by the same reference numerals, and detailed description thereof will be omitted.
The modified examples shown in FIGS. 9 and 10 have a third reflecting portion 153 in place of the first reflecting portion 151 according to the modified examples shown in FIGS. 7 and 8. The third reflecting portion is a plane mirror and is formed on a first reflecting surface 153a which is substantially parallel to the wetted surface 115a of the window plate 115 and at the right end and the other end of the first reflecting surface 153a. It has a pair of second reflecting surfaces 153b inclined with respect to one reflecting surface 153a.

As shown in FIG. 9, one of the second reflecting surfaces 153b of the pair of second reflecting surfaces 153b emits light emitted from the irradiation optical fiber cable 20a and reflected by the irradiation light guide mirror 31, and the pair of second reflecting surfaces. It is configured to be reflective toward the other second reflecting surface 153b of the reflecting surface 153b. The other second reflecting surface 153b is configured to be able to reflect the light from the one second reflecting surface 153b toward the light receiving light guide mirror 32.

In the modified examples shown in FIGS. 9 and 10, as shown in FIG. 9, the light emitted from the irradiation optical fiber cable 20a was reflected by one of the second reflecting surfaces 153b of the pair of second reflecting surfaces 153b. After that, it is reflected by the other second reflecting surface 153b and incident on the light receiving optical fiber cable 20b.
On the other hand, when the optical path is changed by driving the light guide mirror 31 for irradiation by the actuator 41 for changing the angle, as shown in FIG. 10, the light emitted from the optical fiber cable 20a for irradiation is first reflected. After being first reflected by the surface 153a, it is reflected again by the second reflecting unit 150 toward the first reflecting surface 153a. Then, the light emitted from the irradiation optical fiber cable 20a is reflected by the first reflecting surface 153a for the second time, then reflected by the light receiving light guide mirror 32 and incident on the light receiving optical fiber cable 20b.
In the modified examples shown in FIGS. 9 and 10, the optical path (also referred to as the first optical path) 333 shown in FIG. 9 and the optical path (also referred to as the second optical path) 334 shown in FIG. The optical path length in the liquid flow unit 110 can be significantly changed as compared with the form.

(About a modified example of the configuration for changing the optical path length)
11 and 12 are diagrams for explaining an example of a modification of the configuration for changing the optical path length. As shown in FIG. 11, for example, the light-shielding filter device 160 is arranged on the end surface 21a of the irradiation optical fiber cable 20a. As shown in FIG. 12, for example, the light-shielding filter device 160 emits light from the transmission portion 161 that allows the light emitted from the end surface 21a of the irradiation optical fiber cable 20a and the end surface 21a of the irradiation optical fiber cable 20a. It has a light-shielding portion 162 that blocks the light to be generated. The light-shielding filter device 160 is configured so that the positions of the transmission unit 161 and the light-shielding unit 162 can be changed by, for example, a control signal from the control device 14. Note that FIG. 12 is a schematic view of FIG. 11 when the irradiation optical fiber cable 20a is viewed from the irradiation light guide mirror 33.

In the modified example shown in FIG. 11, the irradiation light guide mirror 33 has two reflecting surfaces (first reflecting surface 33a and second reflecting surface 33b) having different angles.
In the modified example shown in FIG. 11, when the light-shielding filter device 160 arranges the light-shielding portion 162 on the lower side of the drawing and forms the transmission portion 161 on the upper side of the drawing, for example, as shown in the upper figure of FIG. 12, for irradiation. The light from the optical fiber cable 20a passes through the transmission portion 161 formed on the upper side of the drawing and is reflected by the first reflecting surface 33a. The optical path in this case is referred to as the first optical path 335.
In the modified example shown in FIG. 11, when the light-shielding filter device 160 arranges the light-shielding portion 162 on the upper side of the drawing and forms the transmission portion 161 on the lower side of the drawing, for example, as shown in the lower figure of FIG. The light from the optical fiber cable 20a passes through the transmission portion 161 formed on the lower side of the drawing and is reflected by the second reflecting surface 33b. The optical path in this case is referred to as a second optical path 336.
In the modified examples shown in FIGS. 11 and 12, the first optical path 335 and the second optical path 336 can be switched by changing the arrangement position of the light-shielding portion 162 in the light-shielding filter device 160.

Two sets of the above-mentioned irradiation optical fiber cable 20a and the above-mentioned irradiation light guide mirror 31 are provided, and an optical path by light emitted from one set and an optical path by light emitted from the other set. The optical paths may be switched by configuring them differently.

(About other embodiments of the spectroscopic analysis method)
For example, as shown in FIGS. 7 and 8, when the number of times light is incident and reflected on the liquid distribution unit 110 in the spectroscopic analyzer 1 is different, the component concentration c and the increment β of the absorbance due to dirt are calculated. The method of is described.
For example, in the modified examples shown in FIGS. 7 and 8, the first optical path 331 and the second optical path 332 differ in the number of repetitions of the incident of light on the liquid flow section 110 and the emission of light from the liquid flow section 110. , The value is different between the term of the increase in absorbance due to dirt in the above-mentioned formula (f2) and the term of the increase in absorbance due to dirt in the above-mentioned formula (f3).

Therefore, for example, the number of repetitions is set to n, and the number of repetitions n is added as a parameter to the term of the increment of absorbance in the equations (f2) and (f3) to calculate the difference in the increase in absorbance due to the difference in the number of repetitions n. It can be reflected in the formula.

For example, in the modified examples shown in FIGS. 7 and 8, the number of repetitions n in the first optical path 331 is one, and the number of repetitions n in the second optical path 332 is two. However, for generalization, the following description will be given. Then, the number of repetitions n in the first optical path 331 is n1, and the number of repetitions n in the second optical path 332 is n2.
As a result, the above equation (f2) can be replaced by the following equation (f6), and the above equation (f3) can be replaced by the following equation (f7).
In the following equations (f6) and (f7), β'is an increment of the absorbance due to fouling per repetition number n.
A'= e × c × l + n1 × β'・ ・ ・ (f6)
A'' = a × e × c × l + n2 × β'・ ・ ・ (f7)

Here, as described above, the change multiple a of the optical path length l and the optical path length l are preset values, and the molar extinction coefficient e is known because of its physical property value. Since the number of repetitions n1 and n2 can also be grasped from the apparatus configuration of the spectroscopic analyzer 1, the unknowns are the component concentration c and the increment β of the absorbance due to dirt. Since there are two equations obtained by changing the optical path length l for two unknowns, the component concentration c can be obtained by the following equation (f8) based on the equations (f6) and (f7). Then, the increment β'of the absorbance due to the stain per repetition n can be obtained by the following equation (f9).
c = {(n2 / n1) x A1-A2} / [{(n2 / n1) -a} x e x l]
... (f8)
β = (A2-a × A1) / (n2-n1 × a) ・ ・ ・ (f9)

That is, in the present embodiment, in the concentration calculation step S50 in FIG. 6, the concentration calculation unit 143 of the control device 14 is filled with the liquid to be analyzed, and the light is incident on the liquid distribution unit 110 through which the light passes and the liquid. The component concentration c is obtained based on the calculation formula including the number of repetitions n of the light emitted from the distribution unit 110 as a parameter.
As a result, when the optical path length is the first optical path length and when the second optical path length is different from the first optical path length, the number of times light is incident and reflected on the liquid distribution unit 110 is different. However, the component concentration c and the increment β'of the absorbance due to the above-mentioned stain can be obtained.

(About still other embodiments of the spectroscopic analysis method)
For example, as described above, the optical path is different between the first optical path 331 and the second optical path 332. For convenience of explanation, in the following description, for example, the optical path length l and the first optical path length in the first optical path 331 are referred to, and the optical path length l and the second optical path length in the second optical path 332 are referred to.

When the optical paths are different as in the first optical path 331 and the second optical path 332, the light transmission length and the light scattering behavior of the portion where the dirt is attached are different for each optical path, and the above-mentioned dirt per repetition number n is different. It is also conceivable that the increment β'of the absorbance due to is different for each optical path.
Therefore, for example, a coefficient representing the difference in absorbance due to dirt between the first optical path 331 and the second optical path 332 is obtained in advance, and by using this coefficient, the difference in absorbance due to dirt between the first optical path 331 and the second optical path 332 is obtained. Can be reflected in the calculation formula.

Specifically, the term of the increase in absorbance in the above formula (f3) is multiplied by a coefficient γ representing the difference in absorbance due to dirt between the first optical path 331 and the second optical path 332. Therefore, the above equation (f2) can be replaced by the following equation (f10), and the above equation (f3) can be replaced by the following equation (f11).
In the following equations (f10) and (f11), β ″ is an increment of absorbance due to contamination in the first optical path 331.
A'= e × c × l + β'' ・ ・ ・ (f10)
A'' = a × e × c × l + γ × β'' ・ ・ ・ (f11)

Here, as described above, the change multiple a of the optical path length l and the optical path length l are preset values, and the molar extinction coefficient e is known because of its physical property value. Since the coefficient γ is also obtained in advance, there are two unknowns, the component concentration c and the increment β of the absorbance due to dirt. Since there are two equations obtained by changing the optical path length l for two unknowns, the component concentration c can be obtained by the following equation (f12) based on the equations (f10) and (f11). Then, the increment β'' of the absorbance due to dirt in the first optical path 331 can be obtained by the following equation (f13). By multiplying the increment β'' of the absorbance due to dirt in the first optical path 331 by the coefficient γ, the increment of the absorbance due to dirt in the second optical path 332 can be obtained.
c = (A1-A2) / {(1-a) × e × l} ... (f12)
β'' = (A2-a × A1) / {γ × (1-a)} ・ ・ ・ (f13)

That is, in the present embodiment, in the concentration calculation step S50 in FIG. 6, the concentration calculation unit 143 of the control device 14 is an optical member (for example, a window plate 115 or the like) that comes into contact with the liquid when the optical path length l is the first optical path length. , The ratio of the absorbance due to dirt on the reflecting portions 130, 130A, 130B, the first reflecting portion 151, the third reflecting portion 153, etc.) to the absorbance due to dirt on the optical member when the optical path length l is the second optical path length. The component concentration c is obtained based on the calculation formula in consideration of.
As a result, even if the light transmission length and the light scattering behavior of the portion where the dirt is attached are different for each optical path, the component concentration c, the increase β'' of the absorbance due to the dirt in the first optical path 331, and the second optical path 332. The increment of absorbance due to dirt γ × β'' can be obtained.

(How to find the coefficient γ)
Hereinafter, an example of how to obtain the coefficient γ described above will be described.
For example, the above-mentioned liquid flow unit 110 is immersed in the actual liquid or simulated liquid of the liquid to be analyzed for a predetermined time, and the optical members of the liquid flow unit 110 (for example, the window plate 115, the reflection units 130, 130A, 130B, and the first reflection) are immersed. Dirt is attached to the portion 151, the third reflective portion 153, etc. in a simulated manner.
The absorbance due to the dirt in different optical paths (for example, the first optical path 331 and the second optical path 332 described above) is obtained using the liquid flow unit 110 to which the dirt is attached in this way, and γ is obtained from the ratio. At that time, it is preferable to fill the liquid distribution unit 110 with a liquid such as pure water so that the measured absorbance matches the absorbance due to dirt.
When the dirt is attached in a simulated manner, it is desirable that the liquid flow in the liquid distribution unit 110 and the immersion conditions such as the concentration, temperature, and immersion time are close to the actual machine usage conditions. In addition, it varies by acquiring a plurality of data under the same conditions, or acquiring a plurality of data with the immersion conditions such as the liquid flow in the liquid flow unit 110, the concentration, the temperature, and the immersion time as parameters and taking the average value. It is desirable to set the value in consideration of.

The present invention is not limited to the above-described embodiment, and includes a modified form of the above-described embodiment and a combination of these embodiments as appropriate.

1 Spectroscopy analyzer 3 Irradiation unit 5 Light receiving unit 10 Analytical device main body 11 Light source 12 Spectrometer 13 Detector 14 Control device 17 Measuring unit 20 Optical fiber cable 30 Light guide mirror 31 Light guide mirror for irradiation 32 Light guide mirror for light reception 40 Change Units 41 and 42 Angle changing actuator 100 Measuring probe 110
115 Window plate 117 Seal member 130 Reflection unit 141 Absorbance calculation unit 143 Concentration calculation unit

Claims (13)

The first measurement step of measuring the intensity of the light passing through the liquid when the optical path length of the light passing through the liquid to be analyzed is the first optical path length, and
A second measurement step of measuring the intensity of light passing through the liquid when the optical path length is a second optical path length different from the first optical path length.
A first absorbance calculation step of calculating the first absorbance when the optical path length is the first optical path length based on the intensity measured in the first measurement step.
A second absorbance calculation step of calculating the second absorbance when the optical path length is the second optical path length based on the intensity measured in the second measurement step.
A concentration calculation step of calculating the concentration of the component to be analyzed in the liquid based on the first absorbance calculated in the first absorbance calculation step and the second absorbance calculated in the second absorbance calculation step.
A spectroscopic analysis method comprising. The concentration calculation step is a calculation formula that includes, as a parameter, the number of repetitions of the incident of the light on the liquid flow section through which the liquid to be analyzed is filled and the light emitted from the liquid flow section. The spectroscopic analysis method according to claim 1, wherein the concentration is calculated based on the above. In the concentration calculation step, the absorbance due to the contamination of the optical member in contact with the liquid when the optical path length is the first optical path length and the contamination of the optical member when the optical path length is the second optical path length. The spectroscopic analysis method according to claim 1, wherein the concentration is calculated based on a calculation formula in consideration of the ratio to the absorbance according to the above. A stain degree calculation step of calculating the stain degree of an optical member in contact with the liquid based on the first absorbance calculated in the first absorbance calculation step and the second absorbance calculated in the second absorbance calculation step.
The spectroscopic analysis method according to any one of claims 1 to 3, further comprising. The liquid distribution department where the liquid to be analyzed can be distributed,
An irradiation unit that irradiates the liquid flowing through the liquid distribution unit with light from a light source from the outside of the liquid distribution unit.
A reflecting unit that reflects light that is irradiated from the irradiation unit and transmitted through the liquid,
A light receiving unit that receives the light reflected by the reflecting unit outside the liquid flow unit, and a light receiving unit.
With
The irradiation unit is a spectroscopic analyzer having a light guide mirror that reflects light from the light source and guides it to the liquid flow unit, and a change unit that changes at least one of the positions or angles of the light guide mirror. A measuring unit that measures the intensity of the light received by the light receiving unit before and after changing at least one of the positions or angles of the light guide mirror by the changing unit.
The first absorbance before changing at least one of the position or angle of the light guide mirror by the changing unit based on the intensity measured by the measuring unit and the intensity of light emitted from the irradiation unit. And the absorbance calculation unit that calculates the second absorbance after changing at least one of the position or angle of the light guide mirror by the change unit.
A concentration calculation unit that calculates the concentration of the component to be analyzed in the liquid based on the first absorbance and the second absorbance calculated by the absorbance calculation unit.
The spectroscopic analyzer according to claim 5. The change portion is such that the position where the light from the light source is irradiated in the reflection portion is not changed before and after changing at least one of the position or the angle of the light guide mirror. The spectroscopic analyzer according to claim 5 or 6, wherein at least one of the positions or angles of the above is changed. The method according to any one of claims 5 to 7, wherein the irradiation unit irradiates the liquid flowing through the liquid distribution unit with the light from the light source as collimated light or as light focused at the reflection unit. Spectral analyzer. The spectroscopic analyzer according to any one of claims 5 to 8, wherein the liquid contains a radioactive substance. A housing having the liquid distribution unit and
A window plate that covers the opening formed in the housing to partition the inside and the outside of the liquid flow portion and transmits the light emitted from the irradiation portion and the light reflected by the reflection portion.
A sealing member that seals the gap between the housing and the window plate,
9. The spectroscopic analyzer according to claim 9. The spectroscopic analyzer according to claim 10, wherein the window plate is made of aluminum oxide. The spectroscopic analyzer according to claim 10 or 11, wherein the sealing member is made of metal. The spectroscopic analyzer according to any one of claims 9 to 12, wherein the reflecting unit is arranged inside the liquid distribution unit and is made of metal.

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