Measurement system, measuring device, and measurement method

Abstract

To measure water quality with high accuracy by a simpler configuration.SOLUTION: A measuring system includes: a first flow channel 13 through which a sample liquid 11 flows; a second flow channel 23 through which a reagent liquid 21 flows, the reagent liquid containing a reagent that reacts with a target component contained in the sample liquid to develop into a first color and a dye of a second color having a wavelength different from a wavelength of the first color; a joining portion 30 where the sample liquid 11 flowing through the first flow channel 13 and the reagent liquid 21 flowing through the second flow channel 23 join; measuring devices 41 and 42 that are provided downstream the joining portion 30 and measure a transmitted light quantity of the first color and a transmitted light quantity of the second color; and a signal processing portion 43 that corrects first absorbance corresponding to the transmitted light quantity of the first color measured by the measuring devices 41 and 42 using second absorbance corresponding to the transmitted light quantity of the second color measured by the measuring devices 41 and 42, and calculates concentration of the target component contained in the sample liquid 11 on the basis of the corrected first absorbance.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a measurement system, a measuring device, and a measuring method.

Background Art

[0002] As an instrument for on-site acquisition of the time change of the concentration of dissolved chemical components contained in a sample solution, a flow-type tap water quality meter is installed at the end of a water pipe near a customer to monitor the residual chlorine concentration, which is the target component contained in tap water, and has been put into practical use. The sample solution taken into the water quality meter is circulated through a thin tube at a constant speed using a pump, and a predetermined amount of a reagent that specifically reacts with the target component is added to the thin tube. In order to react the sample solution with the reagent, for example, a member for heating and temperature adjustment of the mixed solution of the sample solution and the reagent is moved on the flow path to disclose a device for enhancing the heating efficiency for reacting the sample solution with the reagent (see, for example, Patent Document 1). The sample solution to which the reagent is added exhibits color development according to the concentration of the target component. By optically measuring the degree of this color development, the concentration of the target component contained in the sample solution is derived. Such a water quality meter is an automated operation of analytical chemistry performed in an indoor chemical laboratory and has performance equivalent to that of a desktop machine in terms of analysis accuracy. On the other hand, when installing a water quality meter on-site, it may be affected by external factors such as vibration from the installation environment and fluctuations in water pressure, and the flow state of the sample solution inside the flow path may change.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] To perform highly accurate water quality measurements on-site, it is necessary to minimize the changes in the flow conditions described above. Minimizing these changes requires robust piping, control valves, and high-precision pumps, which increases the scale of the system. Therefore, there are problems in terms of securing installation space and cost, making it difficult to easily implement the system.

[0005] The object of the present invention is to provide a measurement system, a measurement device, and a measurement method that can perform highly accurate water quality measurement with a simpler configuration. [Means for solving the problem]

[0006] The measurement system of the present invention is A first channel through which the sample solution flows, A second channel through which a reagent solution containing a reagent that reacts with a target component in the sample solution to produce a first color, and a dye of a second color having a wavelength different from that of the first color, flows. A confluence where the sample solution flowing through the first channel and the reagent solution flowing through the second channel merge, A measuring instrument is provided downstream of the confluence to measure the amount of light transmitted by the first color and the amount of light transmitted by the second color, A correction unit that corrects the first absorbance corresponding to the amount of light transmitted by the first color, as measured by the measuring instrument, using the second absorbance corresponding to the amount of light transmitted by the second color, as measured by the measuring instrument; The system includes a calculation unit that calculates the concentration of the target component contained in the sample solution based on the first absorbance corrected by the correction unit.

[0007] Furthermore, the measuring device of the present invention is A measuring unit that measures the amount of transmitted light of a first color produced by the reaction of a target component in the sample solution with a reagent in the reagent solution, and the amount of transmitted light of a second color, which is the color of a dye in the reagent solution and has a different wavelength from the wavelength of the first color, from a liquid obtained by mixing a sample solution and a reagent solution. A correction unit that corrects the first absorbance corresponding to the amount of light transmitted by the first color, as measured by the measurement unit, using the second absorbance corresponding to the amount of light transmitted by the second color, as measured by the measurement unit; The system includes a calculation unit that calculates the concentration of the target component contained in the sample solution based on the first absorbance corrected by the correction unit.

[0008] Furthermore, the measurement method of the present invention is A process of measuring the amount of transmitted light of a first color produced when a target component in the sample solution reacts with the reagent in the reagent solution to form a liquid mixture of the sample solution and the reagent solution, A process of measuring the amount of transmitted light of a second color, which has a wavelength different from the wavelength of the first color, from a liquid obtained by mixing the sample solution and the reagent solution, wherein the second color is the color of the dye contained in the reagent solution. A process to correct the first absorbance corresponding to the measured amount of transmitted light of the first color using the second absorbance corresponding to the measured amount of transmitted light of the second color, Based on the corrected first absorbance, the concentration of the target component contained in the sample solution is calculated. [Effects of the Invention]

[0009] In this invention, highly accurate water quality measurement can be performed with a simpler configuration. [Brief explanation of the drawing]

[0010] [Figure 1] This figure shows a first embodiment of the measurement system of the present invention. [Figure 2] This figure shows an example of the components included in the signal processing unit shown in Figure 1. [Figure 3] This is a flowchart illustrating an example of a measurement method in the measurement system shown in Figure 1. [Figure 4] This figure shows a second embodiment of the measurement system of the present invention. [Figure 5] This is a flowchart illustrating an example of a measurement method in the measurement system shown in Figure 4. [Figure 6] This is a diagram showing a third embodiment of the measurement system of the present invention. [Figure 7] This is a diagram showing an example of components included in the signal processing unit shown in FIG. 6. [Figure 8(a)] This is a graph showing an example of the change in absorbance according to the amount of transmitted light measured by the second measuring instrument with respect to the time from the start of operation of the second pump. [Figure 8(b)] This is a graph showing an example of the relationship between the time until the absorbance corresponding to the amount of transmitted light measured by the second measuring instrument reaches the peak value from the start of operation of the second pump and the peak value of the absorbance. [Figure 9] This is a diagram showing a fourth embodiment of the measurement system of the present invention.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. (First Embodiment)

[0012] FIG. 1 is a diagram showing a first embodiment of the measurement system of the present invention. As shown in FIG. 1, this embodiment has a first flow path 13, a second flow path 23, a confluence section 30, a reaction tube 31, a first measuring instrument 41, a second measuring instrument 42, and a signal processing unit 43. The measurement device 1 is constituted by the first measuring instrument 41, the second measuring instrument 42, and the signal processing unit 43.

[0013] The first channel 13 is a sample solution tube through which the sample solution 11 stored in the first tank 10 flows. The sample solution 11 stored in the first tank 10 is sent to the first channel 13 using the first pump 12. The second channel 23 is a reagent solution tube through which the reagent solution 21 stored in the second tank 20 flows. The reagent solution stored in the second tank 20 is sent to the second channel 23 using the second pump 22. The reagent solution 21 is a mixture of a reagent that reacts with the target component contained in the sample solution 11 to produce a first color, and a dye of a second color with a different wavelength than the wavelength of the color development. The concentration of the reagent in the reagent solution 21 is adjusted so that there is no reagent excess when mixed with the target component contained in the sample solution 11. The junction 30 connects the first channel 13 and the second channel 23. In other words, at the confluence section 30, the sample solution delivered through the first channel 13 and the reagent solution delivered through the second channel 23 merge. The reaction tube 31 is connected downstream of the confluence section 30 and mixes the sample solution and the reagent solution. When chlorine is used as the target component in the sample solution 11, for example, DPD reagent (which develops a red color) may be used as the reagent in the reagent solution 21, and brilliant blue FCF (blue), which has a different color range than that of the DPD reagent, may be used as the dye in the reagent solution 21. When the target component in the sample solution 11 is something other than chlorine, the system can be easily applied to continuous measurement of other target components by replacing the reagent in the reagent solution 21 with another reagent.

[0014] The first measuring instrument 41 measures the amount of transmitted light only in the wavelength range that reacts with the target component and produces color. The second measuring instrument 42 measures the amount of transmitted light only near the wavelength range of the dye. Specifically, the first measuring instrument 41 and the second measuring instrument 42 irradiate the liquid mixed in the reaction tube 31 with light of a predetermined wavelength and measure the amount of transmitted light at the corresponding wavelength. The first measuring instrument 41 and the second measuring instrument 42 are positioned downstream of the reaction tube 31, and either one can be positioned upstream of the other. The target component contained in the sample solution 11 mixes with the reagent solution 21 as it flows through the reaction tube 31 and exhibits a color reaction. The degree of this color development is proportional to the product of the concentration of the target component in the sample solution 11 and the concentration of the reagent in the reagent solution 21 within the reaction tube 31. As the colored reaction solution flows through the reaction tube 31, it diffuses in the direction of the pipe. As a result, the amount of transmitted light decreases when it passes through the first measuring instrument 41, and then increases over time. On the other hand, the dye contained in the reagent solution 21 diffuses in the direction of the pipe as it flows through the reaction tube 31, similar to the reaction solution. As a result, the transmitted light amount decreases temporarily when it passes through the second measuring instrument 42, and then increases over time. The first measuring instrument 41 and the second measuring instrument 42 each output the value of the transmitted light amount they have measured to the signal processing unit 43. Here, the absorption wavelength ranges measured (detected) by the first measuring instrument 41 and the second measuring instrument 42 are different from each other. Therefore, when the dye contained in the reagent solution 21 passes through the first measuring instrument 41, the amount of transmitted light from the dye contained in the reagent solution 21 does not affect the amount of transmitted light measured by the first measuring instrument 41. Note that the first measuring instrument 41 and the second measuring instrument 42 may be included in a single measuring instrument.

[0015] The signal processing unit 43 calculates the concentration of the target component contained in the sample solution 11 based on the transmitted light quantity measured by the first measuring instrument 41 and the transmitted light quantity measured by the second measuring instrument 42. Figure 2 is a diagram showing an example of the components of the signal processing unit 43 shown in Figure 1. The signal processing unit 43 shown in Figure 1 has a correction unit 431 and a calculation unit 432, as shown in Figure 2. Note that Figure 2 shows only the main components of the signal processing unit 43 shown in Figure 1 that are relevant to this embodiment.

[0016] The correction unit 431 converts the transmitted light quantity value output from the first measuring instrument 41 into an absorbance value (first absorbance). The correction unit 431 converts the transmitted light quantity value output from the second measuring instrument 42 into an absorbance value (second absorbance). The algorithm for converting the transmitted light quantity value to the absorbance value can be any commonly used algorithm and is not specifically defined. The correction unit 431 corrects the first absorbance using the converted second absorbance. The specific correction method will be explained below.

[0017] The first absorbance converted by the correction unit 431 gradually increases over time, reaching a peak value I, and then decreasing, exhibiting a signal profile. This peak value correlates with the product value described above. Similarly, the second absorbance converted by the correction unit 431 also gradually increases over time, reaching a peak value I. R After taking the signal, a decreasing signal profile is shown. This peak value I R This correlates with the amount of reagent solution 21 added at the confluence 30. The correction unit 431 normalizes the first absorbance using the second absorbance and corrects the first absorbance. At this time, the correction unit 431 uses the peak value I of the second absorbance. R The peak value I of the first absorbance is corrected using this. The transmitted light amount of the first color measured by the first measuring instrument 41 and the transmitted light amount of the second color measured by the second measuring instrument 42 are values ​​that are affected by external factors of the same level. For example, during operation, consider a case where the discharge of the reagent solution 21 varies due to disturbances from the installation environment or deterioration of the second pump 22, and the amount added decreases. In this case, the concentration of the reagent contained in the reaction solution in the reaction tube 31 decreases, so even if the concentration of the target component contained in the reaction solution remains constant, the peak value I of the absorbance signal obtained from the first measuring instrument 41 also decreases. However, at the same time, the peak value I of the absorbance signal related to the dye obtained from the second measuring instrument 42 R It also decreases at the same rate. This peak value I R Since it correlates with the concentration of the reagent in reaction tube 31, I RBy normalizing, the concentration value of the target component can be determined. Therefore, the correction unit 431 normalizes the first absorbance corresponding to the amount of transmitted light of the first color measured by the first measuring instrument 41 using the second absorbance corresponding to the amount of transmitted light of the second color measured by the second measuring instrument 42, thereby correcting the first absorbance corresponding to the amount of transmitted light of the first color measured by the first measuring instrument 41 to a value that is not affected by external factors.

[0018] The calculation unit 432 calculates the concentration of the target component contained in the sample solution 11 based on the first absorbance corrected by the correction unit 431. Existing methods may be used for calculating the concentration of the target component based on transmitted light or absorbance. The calculation unit 432 outputs a value indicating the calculated concentration. The output method of the value from the calculation unit 432 may be display, transmission to another device, or any other method depending on how the value will be used.

[0019] The measurement method in the measurement system shown in Figure 1 will be described below. Figure 3 is a flowchart illustrating an example of the measurement method in the measurement system shown in Figure 1.

[0020] First, the first pump 12 is started to flow the sample solution 11 from the first tank 10 through the first channel 13, the confluence section 30, and the reaction tube 31 to the first measuring instrument 41 and the second measuring instrument 42. The second channel 23 is pre-filled with reagent solution 21. After the sample solution 11 fills the first channel 13, the second pump 22 operates for a predetermined time at a predetermined timing to inject the reagent solution 21 into the flow of the sample solution 11 (step S1).

[0021] Subsequently, the first measuring instrument 41 measures the amount of transmitted light from the reaction solution contained in the mixed liquid in the reaction tube 31 (step S2). The second measuring instrument 42 measures the amount of transmitted light from the dye contained in the mixed liquid in the reaction tube 31 (step S3). The first measuring instrument 41 outputs a value indicating the amount of transmitted light of the measured first color to the signal processing unit 43. The second measuring instrument 42 also outputs a value indicating the amount of transmitted light of the measured second color to the signal processing unit 43. Then, the correction unit 431 of the signal processing unit 43 converts the value indicating the amount of transmitted light of the first color output from the first measuring instrument 41 into the first absorbance. The correction unit 431 of the signal processing unit 43 also converts the value indicating the amount of transmitted light of the second color output from the second measuring instrument 42 into the second absorbance. Subsequently, the correction unit 431 corrects the first absorbance using the converted second absorbance (step S4). The correction method is as described above. The correction unit 431 outputs the corrected first absorbance to the calculation unit 432. The calculation unit 432 then calculates the concentration of the target component contained in the sample solution 11 based on the first absorbance output from the correction unit 431 (step S5).

[0022] In this configuration, a reagent solution containing a reagent that reacts with the target component in the sample solution and a dye with a wavelength different from the wavelength of color development when the target component reacts with the reagent is mixed with the sample solution. The first transmitted light amount for color development and the second transmitted light amount for the dye are measured. The first absorbance corresponding to the measured first transmitted light amount is corrected using the second absorbance corresponding to the measured second transmitted light amount, and the concentration of the target component in the sample solution is calculated based on the corrected value. This allows for accurate determination of the concentration of the target component even if there are variations in the amount of reagent added due to disturbances from the installation environment or deterioration of the pump that adds the reagent. A simpler fluid element configuration is possible, and highly accurate water quality measurements can be performed even if there are long-term performance changes. (Second Embodiment)

[0023] Figure 4 shows a second embodiment of the measurement system of the present invention. As shown in Figure 4, this embodiment includes a first flow path 13, a second flow path 23, a confluence section 30, a reaction tube 31, a first measuring instrument 41, a second measuring instrument 42, and a signal processing unit 43. The measuring device 1 is composed of the first measuring instrument 41, the second measuring instrument 42, and the signal processing unit 43. Each component is the same as that in the first embodiment.

[0024] This embodiment does not include the first pump 12, which was present in the first embodiment for sending the sample solution 11 stored in the first tank 10 to the first flow path 13. Furthermore, this embodiment does not include the second pump 22, which was present in the first embodiment for sending the reagent solution 21 stored in the second tank 20 to the second flow path 23. The first tank 10 and the second tank 20 are located above the confluence section 30. This structure allows the sample solution 11 stored in the first tank 10 to be sent to the first flow path 13 and the reagent solution 21 stored in the second tank 20 to be sent to the second flow path 23, using the height from the confluence section 30 to the first tank 10 and the second tank 20, as well as the hydrostatic pressure corresponding to the amount of sample solution 11 in the first tank 10 and the amount of reagent solution 21 in the second tank 20. A control valve 24 is provided in the second flow path 23. The control valve 24 is an on / off valve that adjusts the amount of reagent solution 21 flowing from the second flow path 23 to the confluence section 30. The control valve 24 opens and closes based on an external control signal. The control signal is a signal to control the opening and closing of the control valve 24 according to the timing of adding the reagent solution 21 to the sample solution 11.

[0025] The measurement method in the measurement system shown in Figure 4 will be described below. Figure 5 is a flowchart illustrating an example of the measurement method in the measurement system shown in Figure 4.

[0026] First, the sample solution 11 is flowed from the first tank 10 through the first flow path 13, the confluence section 30, and the reaction tube 31 to reach the first measuring instrument 41 and the second measuring instrument 42. After the sample solution 11 fills the first flow path 13, the control valve 24 is opened, and the reagent solution 21 is injected into the flow of the sample solution 11 (step S11). The opening time of the control valve 24 is a time corresponding to the amount of reagent injected into the sample solution 11.

[0027] Subsequently, the first measuring instrument 41 measures the amount of transmitted light from the reaction solution contained in the mixed liquid in the reaction tube 31 (step S12). Also, the second measuring instrument 42 measures the amount of transmitted light from the dye contained in the mixed liquid in the reaction tube 31 (step S13). The first measuring instrument 41 outputs a value indicating the amount of transmitted light of the measured first color to the signal processing unit 43. The second measuring instrument 42 also outputs a value indicating the amount of transmitted light of the measured second color to the signal processing unit 43. Then, the correction unit 431 of the signal processing unit 43 converts the value indicating the amount of transmitted light of the first color output from the first measuring instrument 41 into the first absorbance. The correction unit 431 of the signal processing unit 43 also converts the value indicating the amount of transmitted light of the second color output from the second measuring instrument 42 into the second absorbance. Subsequently, the correction unit 431 corrects the first absorbance using the converted second absorbance (step S14). The correction method is as described above. The correction unit 431 outputs the corrected first absorbance to the calculation unit 432. The calculation unit 432 then calculates the concentration of the target component contained in the sample solution 11 based on the first absorbance output from the correction unit 431 (step S15).

[0028] In this configuration, a reagent solution containing a reagent that reacts with the target component in the sample solution and a dye with a wavelength different from the wavelength of color development when the target component reacts with the reagent is mixed with the sample solution. The first transmitted light amount for color development and the second transmitted light amount for the dye are measured. The first absorbance corresponding to the measured first transmitted light amount is corrected using the second absorbance corresponding to the measured second transmitted light amount, and the concentration of the target component in the sample solution is calculated based on the corrected value. This allows for accurate determination of the concentration of the target component even if there are variations in the amount of reagent added due to disturbances from the installation environment or deterioration of the control valve that controls the addition of the reagent. A simpler fluid element configuration is possible, and highly accurate water quality measurement can be performed even if there are long-term performance changes. Furthermore, the sample solution 11 stored in the first tank 10 and the reagent solution 21 stored in the second tank 20 are respectively delivered to the first flow path 13 and the second flow path 23 using hydrohead pressure. Therefore, a simpler configuration is possible.

[0029] When the volume of sample solution 11 stored in the first tank 10 decreases, the hydrostatic pressure decreases, and the flow rate of sample solution 11 into the first channel 13 decreases. Similarly, when the volume of reagent solution 21 stored in the second tank 20 decreases, the hydrostatic pressure decreases, and the amount of reagent added from the second channel 23 also decreases. Furthermore, if air bubbles adhere to the first channel 13 or the second channel 23, or if dirt adheres to the inner surface, or if the first channel 13 or the second channel 23 deforms, the flow rate of sample solution 11 and the amount of reagent solution 21 added at the confluence section 30 will also change. Due to these changes in the amount of reagent solution 21 added caused by external factors, the absorbance corresponding to the transmitted light amount of the target component measured by the first measuring instrument 41 changes, but this can be corrected using the same method as in the first embodiment. (Third embodiment)

[0030] Figure 6 shows a third embodiment of the measurement system of the present invention. As shown in Figure 3, this embodiment includes a first flow path 13, a second flow path 23, a confluence section 30, a reaction tube 31, a first measuring instrument 41, a second measuring instrument 42, and a signal processing unit 44. The measuring device 2 is composed of the first measuring instrument 41, the second measuring instrument 42, and the signal processing unit 44. Each of the components other than the signal processing unit 44 is the same as in the first embodiment.

[0031] Figure 7 shows an example of the components provided in the signal processing unit 44 shown in Figure 6. As shown in Figure 6, the signal processing unit 44 has a correction unit 441 and a calculation unit 432. The calculation unit 432 is the same as that in the first embodiment. In addition to the functions provided by the correction unit 431 in the first embodiment, the correction unit 441 has a function to perform time-related corrections. The specific operation will be described later. Note that Figure 2 shows only the main components related to this embodiment from the components provided in the signal processing unit 43 shown in Figure 1.

[0032] This configuration is for calculating the concentration of the target component contained in the sample solution 11 when there are fluctuations in the operation of the first pump 12 or the second pump 22. In Figure 6, the time profile of the absorbance signal obtained when the dye contained in the reagent solution 21 passes through the second measuring instrument 42 includes information about the time from when the reagent solution 21 is added to the sample solution 11 at the confluence 30 until it reaches the second measuring instrument 42. For example, if T2 is the time when the second measuring instrument 42 measures the peak absorbance value corresponding to the amount of transmitted light of the dye contained in the reagent solution 21, and T1 is the time when the operation of the second pump 22 starts in order to add the reagent solution 21 to the sample solution 11, then the difference time (T2-T1) is considered to be approximately the same as the time it takes for the sample solution 11 supplied by the operation of the first pump 12 to reach the first measuring instrument 41 from the confluence 30.

[0033] Figure 8(a) is a graph showing an example of how absorbance changes in response to transmitted light measured by the second measuring instrument 42 with respect to time from the start of operation of the second pump 22. Three cases are shown in Figure 8(a). Comparing Case 1 and Case 2, it can be seen that in Case 2, the time from the start of operation of the second pump 22 to the peak value of absorbance measured by the second measuring instrument 42 is longer than in Case 1, and the peak value is smaller. Comparing Case 2 and Case 3, it can be seen that in Case 3, the time from the start of operation of the second pump 22 to the peak value of absorbance measured by the second measuring instrument 42 is longer than in Case 2, and the peak value is smaller. As described above, the time it takes for the sample liquid 11 supplied by the operation of the first pump 12 to reach the first measuring instrument 41 from the confluence 30 is considered to be approximately the same as the time from the start of operation of the second pump 22 (when the reagent liquid 21 merges with the sample liquid 11) to the peak value of absorbance measured by the second measuring instrument 42. Therefore, a longer time from the start of operation of the second pump 22 until the absorbance measured by the second measuring instrument 42 reaches its peak value means that the time it takes for the sample liquid 11 supplied by the operation of the first pump 12 to reach the first measuring instrument 41 from the confluence 30 is longer. A longer time from the confluence 30 until the first measuring instrument 41 is reached by the operation of the first pump 12 indicates that the flow velocity of the sample liquid 11 is slower, and even with the same length of tubing, diffusion in the direction of the tubing increases, causing the peak value of the concentration to decrease. Thus, the change in the time from the start of operation of the second pump 22 until the absorbance corresponding to the transmitted light amount measured by the second measuring instrument 42 reaches its peak value, and the change in the peak value, is due to the deterioration of the second pump 22 as described above.

[0034] Figure 8(b) is a graph showing an example of the relationship between the time from the start of operation of the second pump 22 until the absorbance corresponding to the transmitted light amount measured by the second measuring instrument 42 reaches its peak value, and the peak value of the absorbance. As shown in Figure 8(b), the peak value of the absorbance signal corresponding to the transmitted light amount measured by the second measuring instrument 42 decreases as the time to reach the peak increases. The correction unit 441 of the signal processing unit 44 has the relationship between time and peak value shown in Figure 8(b) pre-recorded as a relational expression. Based on this relational expression and the peak value of the absorbance corresponding to the transmitted light amount measured by the first measuring instrument 41, the correction unit 441 corrects the absorbance value corresponding to the transmitted light amount measured by the first measuring instrument 41.

[0035] In this embodiment, the relationship between the time from the start of operation of the second pump 22 until the absorbance corresponding to the transmitted light amount measured by the second measuring instrument 42 reaches its peak value, and the peak absorbance value is stored in advance as a relational expression. Based on the stored relational expression and the peak absorbance value corresponding to the transmitted light amount measured by the first measuring instrument 41, the absorbance value corresponding to the transmitted light amount measured by the first measuring instrument 41 is corrected. This makes it possible to correct the decrease in the absorbance signal at the first measuring instrument 41 due to the decrease in the flow rate of the sample liquid 11, in addition to the effects of the first embodiment. (Fourth embodiment)

[0036] Figure 9 shows a fourth embodiment of the measurement system of the present invention. In Figure 9, the measurement device 1 or measurement device 2 shown in the first to third embodiments are omitted. In this embodiment, as shown in Figure 9, a first flow path 13, which is a narrow tube, and a reagent bag 25 in which reagent solution 21 is stored are provided inside the tank 100. Sample solution 11 flows into the tank 100 from the outside. The sample solution 11 and reagent solution 21 are the same as those in the first to third embodiments. The tank 100 has a cylindrical shape with an open top, and the inside is filled with sample solution 11 that flows in from the open top. The tank 100 also has an outflow mechanism 101 that drains the sample solution 11 that overflows from the tank 100 to the outside. The inlet at the upper end of the first flow path 13 is open, and the upper end is positioned lower than the upper liquid level of the tank 100 so that a portion of the sample solution 11 in the tank 100 is continuously introduced from the inlet. The reagent bag 25 is a flexible bag-shaped container connected to the connection part 102 and connected to the second channel 23 to the microchannel forming substrate 32 via the control valve 24, and has a structure that prevents contact with the outside air. The reagent bag 25 is held upright using a support casing jig. The reagent bag 25 is detachable from the connection part 102. The reagent solution 21 stored in the reagent bag 25 is sent to the control valve 24 by the pressure of the sample solution 11 stored in the cylindrical tank 100. The control valve 24 is an on / off valve that adjusts the supply of the reagent solution 21 to the microchannel forming substrate 32. The control valve 24 opens and closes according to an external control signal.

[0037] The microchannel-forming substrate 32 has fine reaction channels (corresponding to the reaction tubes 31 shown in the first to third embodiments) formed therein. Sample liquid 11 flows into the inlet 103 of the reaction channel from the first channel 13, and reagent liquid 21 flows into the intermediate opening 104 of the reaction channel from the reagent bag 25 via the control valve 24. A flow cell detector 45 is provided at the outlet 105 of the reaction channel. The size of the microchannel-forming substrate 32 is reduced by integrating the reaction channels formed on the microchannel-forming substrate 32.

[0038] The flow cell detector 45 is a measuring instrument that measures the amount of light transmitted, equipped with an LED element that periodically emits light in the order of red, green, and blue. The flow cell detector 45 corresponds to the first measuring instrument 41 and the second measuring instrument 42 in the first to third embodiments. The flow cell detector 45 is connected to the waste liquid pipe 106, and the liquid whose amount of light transmitted has been measured is discharged from the waste liquid pipe 106. The flow cell detector 45 transmits the measured value to a signal processing device (not shown, corresponding to the signal processing devices 43 and 44 in the first to third embodiments).

[0039] The system operates as shown in Figure 9. The sample liquid 11 is continuously supplied from above the tank 100 toward the open top surface. When the tank 100 is full of sample liquid 11, any sample liquid 11 that overflows from the tank 100 is discharged to the outside through the discharge mechanism 101. A portion of the sample liquid 11 in the tank 100 is supplied via the first flow path 13 to the inlet 103 of the reaction channel formed in the microchannel forming substrate 32. Since the liquid level of the sample liquid 11 in the tank 100 is maintained at a constant height, the supply pressure of the sample liquid 11 to the inlet 103 of the reaction channel formed in the microchannel forming substrate 32 remains constant. In this state, the sample liquid 11 introduced into the reaction channel reaches the outlet 105, passes through the flow cell detector 45, and is discharged from the waste liquid pipe 106.

[0040] On the other hand, since the reagent bag 25 is held inside the tank 100, it is constantly subjected to the water pressure of the sample solution 11 inside the tank 100. Therefore, by opening the control valve 24 for a certain period of time, a predetermined amount of reagent solution 21 inside the reagent bag 25 can be released. The released reagent solution 21 is added to the sample solution 11 flowing through the reaction channel at an intermediate opening 104 of the reaction channel formed on the microchannel forming substrate 32 via the second channel 23. As the added reagent solution 21 flows through the reaction channel, it gradually reacts with the target component in the sample solution 11 and exhibits color development. When this colored reaction solution flows through the flow cell detector 45, the flow cell detector 45 periodically measures the change in the amount of transmitted light in each wavelength range under the emission of red, green, and blue light.

[0041] The opening timing and opening time interval of the control valve 24 are controlled using an external signal. Furthermore, the time-varying signals of the three transmitted light quantities measured by the flow cell detector 45 are transmitted from the flow cell detector 45 to an external signal processing device, such as a signal processing device. In the external signal processing device, the signal processing described in the first to third embodiments is performed, and the final corrected value of the target component concentration is obtained. The obtained value may be recorded in a storage means such as cloud storage.

[0042] Here, the reagent bag 25 is compressed by the pressure of the sample solution 11 in the tank 100, and deforms as the amount of reagent solution 21 stored inside the reagent bag 25 decreases. As a result of the deformation, the amount of reagent solution 21 added to the sample solution 11 at the intermediate port 104 may fluctuate, but as explained in the first embodiment, correction can be performed using the amount of transmitted light of the dye contained in the reagent solution 21. In addition, if air bubbles or other foreign matter are mixed into the first flow path 13, or if foreign matter is mixed into the sample solution 11, the water flow resistance to the outlet 105 of the sample solution 11 will increase, and the flow velocity will change. Even in that case, an accurate value (concentration value) can be obtained by using the signal processing explained in the third embodiment.

[0043] In this embodiment, the reagent solution 21 is stored in a flexible bag-shaped container, the reagent bag 25, and is placed inside a tank 100 where the sample solution 11 is supplied from the outside and stored. The reagent solution 21 stored in the reagent bag 25 is sent to the reaction channel using the pressure of the sample solution 11 stored in the tank 100 and added to the sample solution 11 flowing through the reaction channel. As a result, in addition to the effects of the first to third embodiments, it becomes unnecessary to provide a special mechanism for sending the sample solution 11 and the reagent solution 21, and a simpler fluid element configuration is possible.

[0044] The above explanation describes how each component is assigned a specific function (process), but this assignment is not limited to those described above. Furthermore, the configurations of the components described above are merely examples and are not limited to them. Combinations of the various embodiments are also acceptable. [Explanation of symbols]

[0045] 1,2 Measuring device 10 First tank 11. Sample solution 12. First pump 13. First channel 20 Second tank 21 Reagent solution 22 Second pump 23 Second channel 24 Control valves 25 Reagent Bags 30 Confluence 31 reaction tube 32 Microchannel formation substrate 41 First measuring instrument 42. Second measuring instrument 43,44 Signal Processing Unit 45 Flow cell detector 100 tanks 101 Outflow mechanism 102 Connection part 103 Entrance 104 Entrance 105 Exit 106 Waste liquid pipe 431,441 Correction section 432 Calculation Unit

Claims

1. A first channel through which the sample solution flows, A second channel through which a reagent solution containing a reagent that reacts with a target component in the sample solution to produce a first color, and a dye of a second color having a wavelength different from that of the first color, flows. A confluence where the sample solution flowing through the first channel and the reagent solution flowing through the second channel merge, A measuring instrument is provided downstream of the confluence section to measure the amount of light transmitted by the first color and the amount of light transmitted by the second color, A correction unit that corrects the first absorbance corresponding to the amount of light transmitted by the first color, as measured by the measuring instrument, using the second absorbance corresponding to the amount of light transmitted by the second color, as measured by the measuring instrument; A measurement system comprising: a calculation unit that calculates the concentration of the target component contained in the sample solution based on the first absorbance corrected by the correction unit.

2. In the measurement system according to claim 1, The correction unit is a measurement system that normalizes the first absorbance using the second absorbance and corrects the first absorbance.

3. In the measurement system according to claim 1 or claim 2, The correction unit is a measurement system that corrects the first absorbance based on a relational expression showing the relationship between the time from when the sample solution and the reagent solution merge at the confluence unit until the second absorbance corresponding to the amount of transmitted light of the second color measured by the measuring instrument reaches its peak value, and the peak value of the first absorbance corresponding to the amount of transmitted light of the first color measured by the measuring instrument.

4. In the measurement system according to claim 1 or claim 2, The first flow path is structured such that the sample liquid flows using the hydrostatic pressure of the sample liquid stored in the first tank. The measurement system is characterized in that the second flow path is structured in which the reagent solution flows using the hydrostatic pressure of the reagent solution stored in the second tank.

5. In the measurement system according to claim 4, A measuring system having a control valve for adjusting the amount of reagent solution flowing from the second flow path to the confluence.

6. In the measurement system according to claim 1 or claim 2, A measuring system having a reaction tube between the confluence and the measuring instrument for mixing the sample solution and the reagent solution.

7. In the measurement system according to claim 1 or claim 2, A tank having the first flow path inside and into which the sample liquid flows from the outside, The tank contains a flexible bag-shaped container that stores the reagent solution, is located within the tank, is connected to the second flow path, and has a structure that prevents contact with the outside air. A measurement system in which the reagent solution stored in the bag-shaped container flows into the second channel due to the pressure of the sample solution in the tank.

8. A measuring unit that measures the amount of transmitted light of a first color produced by the reaction of a target component in the sample solution with a reagent in the reagent solution, and the amount of transmitted light of a second color, which is the color of a dye in the reagent solution and has a different wavelength from the wavelength of the first color, from a liquid obtained by mixing a sample solution and a reagent solution. A correction unit that corrects the first absorbance corresponding to the amount of light transmitted by the first color, as measured by the measurement unit, using the second absorbance corresponding to the amount of light transmitted by the second color, as measured by the measurement unit. A measuring device comprising: a calculation unit that calculates the concentration of the target component contained in the sample solution based on the first absorbance corrected by the correction unit.

9. A process of measuring the amount of transmitted light of a first color produced when a target component in the sample solution reacts with the reagent in the reagent solution to form a liquid mixture of the sample solution and the reagent solution, A process of measuring the amount of transmitted light of a second color, which has a wavelength different from the wavelength of the first color, from a liquid obtained by mixing the sample solution and the reagent solution, wherein the second color is the color of the dye contained in the reagent solution. A process to correct the first absorbance corresponding to the measured amount of transmitted light of the first color using the second absorbance corresponding to the measured amount of transmitted light of the second color, A measurement method comprising the process of calculating the concentration of the target component contained in the sample solution based on the corrected first absorbance.

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