Management method, management system, and program

Abstract

To provide a method of accurately measuring boron concentration in a solution containing alkali.SOLUTION: A method of measuring boron concentration in a solution containing alkali and boron is provided, the method comprising: introducing acid into the solution until pH of the solution reaches a predetermined value; introducing mannitol into the solution; introducing alkali into the solution until pH of the solution reaches a predetermined value; and measuring boron concentration in the solution based on an amount of the introduced alkali.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a measurement method, a measurement system, and a program.

Background Art

[0002] In a facility for processing debris from a nuclear power plant, there is a safety system that injects boric acid into a solution containing radioactive substances in order to ensure safety. In this safety system, it is necessary to control the boron concentration so that the radioactive substances do not reach criticality. For example, Patent Document 1 discloses a method for measuring the boron concentration in a primary coolant. Since boric acid present in a sample is a weak acid, solid mannitol is added to prepare the sample, and the boron concentration is measured by neutralization titration of the prepared sample with a sodium hydroxide solution. However, in the above safety system, sodium pentaborate is injected as boric acid. Due to the influence of sodium contained in sodium pentaborate, the sodium concentration in the solution changes, making it difficult to measure the boron concentration by neutralization titration with a sodium hydroxide solution.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There is a need for a method for accurately measuring the boron concentration in a solution in which an alkali is present.

[0005] The present disclosure provides a measurement method, a measurement system, and a program that can solve the above problems.

Means for Solving the Problems

[0006] The measurement method according to the present disclosure is a measurement method for measuring the boron concentration of a solution containing alkali and boron, comprising the steps of injecting an acid into the solution until the pH of the solution reaches a predetermined value, injecting mannitol into the solution, injecting an alkali into the solution until the solution is neutralized, and measuring the boron concentration of the solution based on the injection amount of the alkali.

[0007] The measurement system according to the present disclosure is a measurement system for measuring the boron concentration of a solution containing alkali and boron, comprising means for injecting an acid into the solution until the pH of the solution reaches a predetermined value, means for injecting mannitol into the solution, means for injecting an alkali into the solution until the solution is neutralized, and means for measuring the boron concentration of the solution based on the injection amount of the alkali.

[0008] The program according to the present disclosure causes a computer to execute a process for measuring the boron concentration of a solution containing alkali and boron, the process comprising the steps of injecting an acid into the solution until the pH of the solution reaches a predetermined value, injecting mannitol into the solution, injecting an alkali into the solution until the solution is neutralized, and measuring the boron concentration of the solution based on the injection amount of the alkali.

Advantages of the Invention

[0009] According to the measurement method, measurement system, and program of the present disclosure, the boron concentration can be accurately measured.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0011] <First Embodiment> Hereinafter, the method for measuring the boron concentration according to the first embodiment of the present disclosure will be described with reference to FIGS. 1 to 3. (Configuration) FIG. 1 is a diagram showing an example of the measurement system according to the first embodiment. The measurement system 100 includes a container 1 for storing a solution to be measured for boron concentration, a pipe 2 for guiding the solution of debris treatment equipment (not shown) to the container 1, a pipe 3 for discharging the solution from the container 1, a pH meter 4 for measuring the pH of the solution, an acid injection device 5 for injecting acid into the container 1, a mannitol injection device 6 for injecting mannitol into the container 1, a sodium injection device 7 for injecting sodium hydroxide into the container 1, and a measurement device 10. The solution supplied from the debris treatment equipment to the container 1 through the pipe 2 is a liquid in which sodium pentaborate is injected into water mixed with radioactive substances and concrete. The operations of the acid injection device 5, the mannitol injection device 6, and the sodium injection device 7 are controlled by the measurement device 10. Further, the pH meter 4 is connected to the measurement device 10, and the pH of the solution measured by the pH meter 4 is sent to the measurement device 10. The measurement device 10 controls the injection operations of the acid injection device 5 and the sodium injection device 7 based on the pH of the solution measured by the pH meter 4. The specific control method will be described later. A valve V1 is provided in the pipe 2, and a valve V2 is provided in the pipe 3. The opening and closing of the valve V1 and the valve V2 are controlled by the measurement device 10. When the valve V1 is opened, the solution is supplied from the debris treatment equipment to the container 1. When the valve V2 is opened, the solution in the container 1 is discharged.

[0012] The measurement device 10 includes an acquisition unit 11, a control unit 12, a concentration measurement unit 13, an output unit 14, and a storage unit 15. The acquisition unit 11 acquires the pH of the solution in the container 1 measured by the pH meter 4. The acquisition unit 11 records the acquired pH in the storage unit 15 together with the time. The control unit 12 controls the acid injection device 5, the mannitol injection device 6, the sodium injection device 7, the valve V1, and the valve V2. For example, while monitoring the pH measured by the pH meter 4, the control unit 12 controls the acid injection device 5 to inject hydrochloric acid or sulfuric acid into the container 1 in predetermined amounts from the acid injection device 5 until the influence of sodium contained in sodium borate disappears. The control unit 12 controls the mannitol injection device 6 to inject a predetermined amount of mannitol from the mannitol injection device 6 into the container 1. After the influence of sodium is removed and mannitol is injected, the control unit 12 controls the sodium injection device 7 for the solution and injects sodium hydroxide into the container 1 from the sodium injection device 7 in predetermined amounts to perform neutralization titration. For example, the control unit 12 opens the valve V2 to discharge the solution after performing neutralization titration, and then opens the valve V1 to supply a predetermined amount of solution from the debris treatment facility to the container 1. Thereby, the solution to be titrated is exchanged.

[0013] The concentration measurement unit 13 measures the boron concentration of the solution based on the injection amount of sodium hydroxide in the neutralization titration. Further, the concentration measurement unit 13 may measure the sodium concentration of the solution based on the injection amount of the acid (Second Embodiment), or may perform impurity evaluation in the solution (Third Embodiment). The output unit 14 outputs the boron concentration of the solution and the like to a display device or the like. The storage unit 15 stores various information such as the time-series pH acquired by the acquisition unit 11, the injection amount of the acid injected into the solution from the acid injection device 5 under the control of the control unit 12, and the injection amount of sodium injected into the solution from the sodium injection device 7 under the control of the control unit 12.

[0014] Next, with reference to FIG. 2, a method for calculating the boron concentration according to the first embodiment will be described. The vertical axis of the titration curve in Fig. 2 indicates the pH of the solution, and the horizontal axis indicates the titration amount. In this embodiment, in order to cancel out the influence of sodium contained in sodium pentaborate, first hydrochloric acid or sulfuric acid is added to adjust the pH to about 4.0 to 5.5, then mannitol is added, and thereafter, the boron concentration is measured by neutralization titration with sodium hydroxide. P1 in Fig. 2 indicates the titration amount at which the addition of acid ends, and the pH of the solution at this time is 4.0 to 5.5. P2 in Fig. 2 indicates the inflection point at which the addition of sodium hydroxide ends. The titration amount h1 in Fig. 2 corresponds to the sodium concentration of the solution, and the titration amount h2 corresponds to the boron concentration of the solution. By adding hydrochloric acid or sulfuric acid in this way to cancel out the influence of sodium and then adding an alkaline reagent, it becomes possible to measure the boron concentration without the influence of sodium. Strictly speaking, since the influence of sodium cannot be completely canceled out, the measurement result of boric acid by this method will include an error. This is because the pH of boric acid alone varies somewhat depending on the concentration and temperature, and the pH after adding an acid equimolar to sodium ions is not clear. However, even if it is assumed that the pH deviates from that of boric acid alone by about 0.5, at most about 0.1 (mmol / L) of acid (acid concentration when pH is 4) is added in excess. At this time, the concentration of boron becomes an error of 0.1 (mmol / L) × 10.8 = 1.1 (mg / L). However, since the boron concentration of the solution supplied from the debris treatment facility to container 1 is several hundred to several thousand (mg / L), it is a sufficiently small value and an error that can be ignored. Also, in the above description, the pH of the solution when the addition of acid ends is set to 4.0 to 5.5, but this range can be adjusted as appropriate.

[0015] (Operation) Next, with reference to Fig. 3, the flow of the boron concentration measurement process of the first embodiment will be described. Fig. 3 is a flowchart showing an example of the measurement process according to the first embodiment. The acquisition unit 11 continuously acquires the pH measured by the pH meter 4 during the following processes, and records the acquired pH in the storage unit 15 in association with the time. First, an acid is injected into the solution in the container 1 (step S1). The control unit 12 controls the acid injection device 5 to inject the acid in predetermined amounts until the pH acquired by the acquisition unit 11 reaches 4.0 to 5.5. When the pH reaches 4.0 to 5.5, the control unit 12 ends the injection of the acid. Next, mannitol is injected into the solution in the container 1 (step S2). The control unit 12 controls the mannitol injection device 6 to inject mannitol at a predetermined concentration in a predetermined amount. After injecting mannitol, sodium hydroxide is then injected into the solution in the container 1 (step S3). The control unit 12 controls the sodium injection device 7 to inject sodium hydroxide until the pH acquired by the acquisition unit 11 becomes a value within a predetermined range indicating neutrality and the change in pH reaches the maximum and then converges (at least until reaching the inflection point of the titration curve). When the injection of sodium hydroxide is completed, the concentration measurement unit 13 measures the boron concentration from the injection amount of sodium hydroxide in step S3 (step S4). For example, a table associating the injection amount of sodium hydroxide with the boron concentration may be registered in the storage unit 15 in advance, and the concentration measurement unit 13 may calculate the boron concentration of the solution based on the injection amount in step S3 and this table.

[0016] Next, the concentration measurement unit 13 records and outputs the measured boron concentration (step S5). For example, the concentration measurement unit 13 records the boron concentration in the storage unit 15 in association with the time when the boron concentration is calculated. As a result, the time-series boron concentration of the container 1 is recorded in the storage unit 15. Also, the concentration measurement unit 13 outputs the boron concentration to the output unit 14. The output unit 14 outputs the boron concentration to a display device or the like (step S5).

[0017] Next, the measuring device 10 determines whether to end the monitoring of the boron concentration (step S6). For example, when the monitor instructs the measuring device 10 to end the monitoring of the boron concentration, the measuring device 10 determines to end the monitoring of the boron concentration. If not (step S6; No), the control unit 12 controls the valves V1 and V2 to replace the solution (step S7). For example, the control unit 12 opens the valve V2 to discharge the solution in the container 1, then closes the valve V2, and opens the valve V1 to supply the solution from the debris treatment facility to the container 1. When a predetermined amount of the solution is supplied, the control unit 12 closes the valve V1. Then, the processing from step S1 is repeatedly executed. When ending the monitoring of the boron concentration (step S6; Yes), the processing in FIG. 3 is ended.

[0018] (Effect) According to the first embodiment, even when sodium is contained in the solution, the influence of sodium is canceled by adding an acid, and then mannitol is injected, and the boron concentration of the solution can be measured by performing neutralization titration with an alkali. Further, according to the first embodiment, during the measurement of the boron concentration in the container 1, the control unit 12 closes the valves V1 and V2, and after the measurement of the boron concentration, the valves V1 and V2 are opened to replace the solution. With such a configuration, the boron concentration in the latest state of the solution in the debris treatment facility can be measured, and the constant monitoring of the boron concentration online can be realized.

[0019] <Second Embodiment> Hereinafter, a method for measuring the boron concentration and the like according to the second embodiment of the present disclosure will be described with reference to FIG. 4. (Configuration) The configuration of the measurement system 100 in the second embodiment is the same as that in the first embodiment. In the second embodiment, the concentration measurement unit 13 measures not only the boron concentration but also the sodium concentration of the solution.

[0020] (Operation) FIG. 4 is a flowchart showing an example of the measurement process according to the second embodiment. The same reference numerals are given to the same processes as in the first embodiment, and they will be briefly described. The control unit 12 controls the acid injection device 5 to inject acid until the pH of the solution becomes 4.0 to 5.5 (step S1). Next, the control unit 12 controls the mannitol injection device 6 to inject a predetermined amount of mannitol at a predetermined concentration (step S2). Next, the control unit 12 controls the sodium injection device 7 to inject sodium hydroxide until the solution is neutralized (step S3). Next, the concentration measurement unit 13 measures the sodium concentration of the solution from the acid injection amount in step S1 and measures the boron concentration from the sodium hydroxide injection amount in step S3 (step S4a). For example, a table or the like associating the acid injection amount and the sodium concentration is registered in the storage unit 15 in advance, and the concentration measurement unit 13 calculates the sodium concentration of the solution based on the injection amount in step S1 and this table. Also, for example, the concentration measurement unit 13 calculates the boron concentration of the solution based on the injection amount in step S3 and a table associating the sodium hydroxide injection amount and the boron concentration.

[0021] Next, the concentration measurement unit 13 records and outputs the measured sodium concentration and boron concentration (step S5a). For example, the concentration measurement unit 13 records the sodium concentration in the storage unit 15 in association with the time when the sodium concentration is calculated, and outputs the sodium concentration to the output unit 14. Also, for example, the concentration measurement unit 13 records the boron concentration in the storage unit 15 in association with the time when the boron concentration is calculated, and outputs the boron concentration to the output unit 14. As a result, the time-series sodium concentration and boron concentration of the container 1 are recorded in the storage unit 15. The output unit 14 outputs the sodium concentration and the boron concentration to a display device or the like (step S5a). The measuring device 10 repeatedly executes the processes from step S1 while controlling the opening and closing of the valve V1 and the valve V2 to replace the solution in the container 1 until the monitoring of the boron concentration is completed (step S6) (step S7).

[0022] (Effect) Sodium pentaborate is injected into the solution of the debris treatment facility. For safety system management, it is necessary to monitor and manage not only the boron concentration but also the sodium concentration of the solution. According to the second embodiment, it is possible to constantly monitor the boron concentration and the sodium concentration in the latest state of the solution of the debris treatment facility.

[0023] <Third Embodiment> Hereinafter, a method for measuring the boron concentration and the like according to the third embodiment of the present disclosure will be described with reference to FIGS. 5 to 6. (Configuration) The configuration of the measurement system in the third embodiment is the same as that in the first embodiment. In the third embodiment, the concentration measurement unit 13 not only measures the boron concentration and sodium concentration, but also evaluates impurities (substances that affect the measurement of boron concentration and sodium concentration) present in the solution. The vertical axis of the graph shown in FIG. 5 represents pH, and the horizontal axis represents boron concentration. Here, since the concentration ratio of sodium to boron is 1:5 in the solution injected with sodium pentaborate, the relationship between the boron concentration and pH in the state where sodium / boron in the solution is 0.2 is preliminarily sorted out to obtain the graph 51 in FIG. 5. Then, the information corresponding to the graph 51 is recorded in the storage unit 15. The concentration measurement unit 13 measures the boron concentration and sodium concentration by the same process as in the second embodiment, and evaluates the degree of impurities in the solution by comparing the measured sodium / boron ratio with the ideal sodium / boron ratio (=0.2) in the solution. For example, the concentration measurement unit 13 calculates the pH of the solution assuming no influence from other substances based on the measured boron concentration and sodium concentration, plots the relationship between the measured boron concentration and the calculated pH on the graph shown in FIG. 5 (for example, points 52 to 55), and calculates the distance (deviation) from the graph 51. Also. For example, the concentration measurement unit 13 plots the relationship between the measured boron concentration and the pH of the solution measured by the pH meter 4 before adding the acid on the graph shown in FIG. 5 (for example, points 52 to 55), and calculates the distance (deviation) from the graph 51. The larger the calculated deviation amount, the higher the possibility that there are impurities in the solution that affect the measurement of boron concentration and sodium concentration. For example, in the case of point 53, it is a measurement result when it is considered that there are not many impurities. The measurement results of points 52, 54, and 55 suggest the presence of impurities. However, since the distance (deviation) from the graph 51 does not determine the presence or amount of impurities, it is used as a reference index.

[0024] (Operation) FIG. 6 is a flowchart showing an example of the measurement process according to the third embodiment. The same processes as in the second embodiment are denoted by the same reference numerals and will be briefly described. The acquisition unit 11 continuously acquires the pH measured by the pH meter 4 during the following processes, associates the acquired pH with the time, and records it in the storage unit 15. Further, information corresponding to the graph in FIG. 5 (for example, the pH at which the concentration ratio of sodium / boron is 0.2 for each boron concentration) is pre-recorded in the storage unit 15.

[0025] First, an acid is injected into the solution in the container 1 (step S1). When the pH becomes 4.0 to 5.5, mannitol is injected into the solution in the container 1 (step S2). Next, sodium hydroxide is injected into the solution in the container 1 (step S3). Next, the concentration measurement unit 13 measures the sodium concentration and the boron concentration and evaluates the amount of impurities (step S4b). For example, the concentration measurement unit 13 calculates the distance (distance 52a in the case of point 52 in FIG. 5) between the point indicating the relationship between the pH of the solution before step S1 and the boron concentration measured in step S4b and the graph 51, and evaluates the amount of impurities according to the magnitude of the calculated distance. It is suggested that the longer this distance, the higher the possibility of a large amount of impurities, and the shorter the distance, the smaller the amount of impurities. For example, a table or the like associating the distance from the graph 51 with the amount of impurities contained in the solution is pre-registered in the storage unit 15, and the concentration measurement unit 13 may evaluate the amount of impurities based on the calculated distance and this table.

[0026] Next, the concentration measurement unit 13 records and outputs the measured sodium concentration, boron concentration, and the evaluation result of the amount of impurities (step S5b). For example, the concentration measurement unit 13 records the sodium concentration, boron concentration, and the evaluation result of the amount of impurities in the storage unit 15 together with the time when they are calculated. Further, the concentration measurement unit 13 outputs the sodium concentration, boron concentration, and the evaluation result of the amount of impurities to the output unit 14. The output unit 14 outputs the sodium concentration, boron concentration, and the evaluation result of the amount of impurities to a display device or the like (step S5b). The measuring device 10 repeatedly executes the processing from step S1 while controlling the opening and closing of the valve V1 and the valve V2 to replace the solution in the container 1 until the monitoring of the boron concentration is completed (step S6) (step S7).

[0027] (Effect) According to the third embodiment, it is possible to measure the sodium concentration and boron concentration of the solution supplied from the debris treatment facility and evaluate the amount of impurities contained in the solution.

[0028] FIG. 7 is a diagram showing an example of the hardware configuration of the measurement system according to each embodiment. The computer 900 includes a CPU 901, a main storage device 902, an auxiliary storage device 903, an input / output interface 904, and a communication interface 905. The above-described measurement device 10 is implemented in the computer 900. And each of the above-described functions is stored in the auxiliary storage device 903 in the form of a program. The CPU 901 reads the program from the auxiliary storage device 903 and expands it in the main storage device 902, and executes the above processing according to the program. Also, the CPU 901 secures a storage area in the main storage device 902 according to the program. Further, the CPU 901 secures a storage area in the auxiliary storage device 903 for storing data during processing according to the program. The measurement device 10 may be configured by a plurality of computers 900. For example, the control unit 12 and other functional units may be implemented in separate computers, or the control unit 12 may be implemented in a plurality of computers for each control target, and a plurality of computers may be used in parallel to control the acid injection device 5, the mannitol injection device 6, the sodium injection device 7, the valve V1, and the valve V2.

[0029] A program for realizing all or part of the functions of the measuring device 10 may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be read into a computer system and executed to perform the processing by each functional unit. Here, the "computer system" shall include hardware such as an OS and peripheral devices. Also, the "computer system" shall include a homepage providing environment (or display environment) if the WWW system is used. Further, the "computer-readable recording medium" refers to a portable medium such as a CD, DVD, USB, etc., and a storage device such as a hard disk built into a computer system. Also, when this program is distributed to the computer 900 via a communication line, the computer 900 that has received the distribution may expand the program in the main storage device 902 and execute the above processing. Also, the above program may be for realizing a part of the functions described above, and may further be realizable in combination with a program already recorded in the computer system for realizing the functions described above.

[0030] As described above, some embodiments according to the present disclosure have been described, but all of these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalent scope thereof.

[0031] <Supplementary Note> The measurement method, measurement system, and program described in the embodiments are understood as follows, for example.

[0032] (1) The measurement method according to the first aspect is a measurement method for measuring the boron concentration of a solution containing alkali (sodium) and boron, comprising the steps of injecting an acid into the solution until the pH of the solution reaches a predetermined value, injecting mannitol into the solution, injecting sodium into the solution until the pH of the solution reaches a predetermined value, and measuring the boron concentration of the solution based on the injection amount of the alkali. Thereby, the boron concentration in the solution in which alkali is present can be accurately measured.

[0033] (2) The measurement method according to the second aspect is the measurement method of (1), which is a measurement method for measuring the boron concentration of a solution containing alkali and boron, comprising the steps of injecting an acid into the solution until the pH of the solution reaches a predetermined value, injecting mannitol into the solution, injecting alkali into the solution until the pH of the solution reaches a predetermined value, measuring the boron concentration of the solution based on the injection amount of the alkali, and measuring the alkali concentration of the solution based on the injection amount of the acid. Thereby, the boron concentration and the alkali concentration in the solution in which alkali is present can be accurately measured.

[0034] (3) The measurement method according to the third aspect is the measurement method of (2), further comprising the step of comparing information indicating the relationship between the pH of the solution and the concentration of boron when the ratio of alkali and boron contained in the solution is a predetermined set value, and information indicating the relationship between the pH of the solution before injecting the acid into the solution and the boron concentration measured in the step of measuring the boron concentration, to evaluate the amount of impurities contained in the solution. Thereby, the amount of impurities in the solution can be evaluated.

[0035] (4) The measurement method according to the fourth aspect is the measurement method of (2), and when the ratio of alkali and boron contained in the solution is a predetermined set value, information indicating the relationship between the pH of the solution and the concentration of boron, and the boron concentration measured in the step of measuring the boron concentration and the pH of the solution calculated from the alkali concentration measured in the step of measuring the alkali concentration and the boron concentration measured in the step of measuring the boron concentration. And further comprising a step of evaluating the amount of impurities contained in the solution by comparing the information indicating the relationship. Thereby, the amount of impurities in the solution can be evaluated.

[0036] (5) The measurement system according to the fifth aspect is a measurement system for measuring the boron concentration of a solution containing alkali and boron, and means for injecting an acid into the solution until the pH of the solution reaches a predetermined value, means for injecting mannitol into the solution, means for injecting an alkali into the solution until the solution is neutralized, and means for measuring the boron concentration of the solution based on the injection amount of the alkali.

[0037] (6) The measurement system according to the sixth aspect includes means for guiding a solution obtained by injecting sodium pentaborate into a liquid in which radioactive substances are mixed from a nuclear facility to a measurement container, means for injecting an acid into the solution in the measurement container until the pH of the solution reaches a predetermined value, means for injecting mannitol into the solution in the measurement container, means for injecting an alkali into the solution in the measurement container until the solution is neutralized, means for measuring the boron concentration of the solution based on the injection amount of the alkali, and means for discharging the solution from the measurement container. Thereby, continuous monitoring of the boron concentration of the solution becomes possible.

[0038] (7) The program according to the seventh aspect causes a computer to execute a process for measuring the boron concentration of a solution containing an alkali and boron, the process including steps of injecting an acid into the solution until the pH of the solution reaches a predetermined value, injecting an alkali into the solution, injecting an alkali into the solution until the solution is neutralized, and measuring the boron concentration of the solution based on the injection amount of the alkali.

Explanation of Signs

[0039] 10 ··· Measuring device 11 ··· Acquisition unit 12 ··· Control unit 13 ··· Concentration measurement unit 14 ··· Output unit 15 ··· Storage unit 1 ··· Container 2, 3 ··· Pipes 4 ··· pH meter 5 ··· Acid injection device 6 ··· Mannitol injection device 7 ··· Sodium injection device 100 ··· Measurement system V1, V2 ··· Valves 900 ··· Computer 901 ··· CPU 902 ··· Main memory device 903 ··· Auxiliary storage device 904 ··· Input / output interface 905 ··· Communication interface

Claims

1. A measurement method for measuring the boron concentration of a solution containing an alkali and boron, comprising: injecting an acid into the solution until the pH of the solution reaches a predetermined value; injecting mannitol into the solution; injecting an alkali into the solution until the solution is neutralized; measuring the boron concentration of the solution based on the injection amount of the alkali; and a measurement method having the above steps.

2. measuring the alkali concentration of the solution based on the injection amount of the acid; The measurement method according to claim 1, further comprising the above step.

3. Comparing information indicating the relationship between the pH of the solution and the boron concentration when the ratio of the alkali and boron contained in the solution is a predetermined set value, and information indicating the relationship between the pH of the solution before injecting the acid into the solution and the boron concentration measured in the step of measuring the boron concentration, to evaluate the amount of impurities contained in the solution; The measurement method according to claim 1 or claim 2, further comprising the above step.

4. Comparing information indicating the relationship between the pH of the solution and the boron concentration when the ratio of the alkali and boron contained in the solution is a predetermined set value, and information indicating the relationship between the pH of the solution calculated from the boron concentration measured in the step of measuring the boron concentration and the alkali concentration measured in the step of measuring the alkali concentration and the boron concentration measured in the step of measuring the boron concentration, to evaluate the amount of impurities contained in the solution; The measurement method according to claim 2, further comprising the above step.

5. A measurement system for measuring the boron concentration of a solution containing an alkali and boron, comprising: means for injecting an acid into the solution until the pH of the solution reaches a predetermined value; means for injecting mannitol into the solution; means for injecting an alkali into the solution until the solution is neutralized; means for measuring the boron concentration of the solution based on the injection amount of the alkali; A measurement system having the above.

6. means for guiding a solution obtained by injecting sodium pentaborate into a liquid mixed with a radioactive substance from a nuclear facility to a measurement container; means for injecting an acid into the solution in the measurement container until the pH of the solution reaches a predetermined value; means for injecting mannitol into the solution in the measurement container; means for injecting an alkali into the solution in the measurement container until the solution is neutralized; means for measuring the boron concentration of the solution based on the injection amount of the alkali; means for discharging the solution from the measurement container; A measurement system having the above.

7. On a computer, A process for measuring the boron concentration of a solution containing an alkali and boron, a step of injecting an acid into the solution until the pH of the solution reaches a predetermined value; a step of injecting mannitol into the solution; a step of injecting an alkali into the solution until the solution is neutralized; a step of measuring the boron concentration of the solution based on the injection amount of the alkali; A program for causing the above process to be executed.

Images