Infrared spectrum heavy water concentration measuring instrument

Abstract

The invention relates to the technical field of heavy water concentration measurement, in particular to an infrared spectrum heavy water concentration measuring instrument which comprises a sample dilution unit, a temperature control unit, a light path unit, a colorimetric pool unit and a detector unit. Injecting the mixed sample into a colorimetric pool unit; the colorimetric pool unit comprises a standard solution colorimetric pool and a sample colorimetric pool, and the sample colorimetric pool is used for heavy water concentration detection; the temperature control unit is used for controlling the temperature of the sample dilution unit and the colorimetric pool unit; the light path unit is used for emitting infrared light to the sample colorimetric pool; and the detector unit is used for controlling the functions of other units and detecting the concentration of the heavy water sample in the sample colorimetric pool. The device realizes the functions of automatically analyzing the heavy water concentration, controlling the heavy water concentration measurement temperature, automatically calibrating the device by adopting a standard sample solution and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of heavy water concentration measurement, and particularly to an infrared spectroscopy heavy water concentration measuring instrument. Background Art

[0002] In a heavy water reactor nuclear power unit, heavy water serves as a moderator and coolant of the nuclear power unit. To ensure the safe and stable operation of the power plant, the heavy water concentration must be controlled within a certain range. Analytical detection methods for heavy water concentration include the specific gravity method, mass spectrometry, gas chromatography, nuclear magnetic resonance method, and infrared spectroscopy method, etc. Among them, the infrared spectroscopy method has the characteristics of rapid determination and simple operation, so this method is widely used. However, in actual laboratory use, it is found that there are some disadvantages in measuring heavy water concentration by infrared spectroscopy. For example, when the heavy water concentration range is in the interval of 2-20%, the correlation coefficient between absorbance and heavy water concentration is low, and the analysis accuracy of heavy water decreases. At the same time, the infrared vibration frequency of water molecules is related to temperature. When the temperature changes, the infrared absorption spectrum of heavy water will shift, which will cause the measurement result to change. Since the analysis of heavy water concentration by infrared spectroscopy requires the use of a standard heavy water concentration sample to make a standard curve, if there is a difference in temperature between when making the standard curve and when measuring the sample to be tested, it will cause an error in heavy water concentration analysis. At the same time, when preparing a standard sample of heavy water concentration in the laboratory, it is very easy to be contaminated by moisture in the air, affecting the accuracy of the standard sample concentration. At the same time, when analyzing heavy water, a 0.2 mm colorimetric cell is used. Because the distance between the colorimetric cells is small, the colorimetric cell is easily blocked by particulate impurities in the heavy water. Summary of the Invention

[0003] The present invention provides an infrared spectroscopy heavy water concentration measuring instrument, which is used to solve the problems in the prior art that the absorbance, temperature, and moisture in the air affect the measurement result in the measurement of heavy water concentration by infrared spectroscopy, and the colorimetric cell is blocked by impurities in the heavy water.

[0004] The technical solution of the present invention is as follows:

[0005] The present invention provides an infrared spectroscopy heavy water concentration measuring instrument, which includes a sample dilution unit, a temperature control unit, an optical path unit, a colorimetric cell unit, and a detector unit. The sample dilution unit is used to mix the heavy water sample with light water to adjust the concentration of the sample, and inject the mixed sample into the colorimetric cell unit; the colorimetric cell unit includes a standard solution colorimetric cell and a sample colorimetric cell, and the sample colorimetric cell is used for detecting the heavy water concentration; the temperature control unit is used to control the temperature of the sample dilution unit and the colorimetric cell unit; the optical path unit is used to emit infrared light to the sample colorimetric cell; the detector unit is electrically connected to other units, and the detector unit is used to control the functions of other units and detect the concentration of the heavy water sample in the sample colorimetric cell.

[0006] In some embodiments, the sample dilution unit includes a sample tank, a light water tank, a weight measuring instrument, and a sample dilution tank. The sample tank and the light water tank are respectively connected to the sample dilution tank through pipelines. A weight measuring instrument is provided on the sample dilution tank, and the weight measuring instrument is used to accurately measure the weights of the heavy water sample and the light water added into the sample dilution tank, so as to accurately dilute the heavy water sample.

[0007] In some embodiments, the sample dilution tank of the sample dilution unit is connected to a waste liquid tank B, and the waste liquid tank B is used to collect the waste liquid discharged from the sample dilution tank; a plunger pump B is provided on the pipeline connecting the sample tank and the sample dilution tank, and a plunger pump C is provided on the pipeline connecting the light water tank and the sample dilution tank.

[0008] In some embodiments, the sample colorimetric cell is respectively connected to a sample inlet pipeline and a sample outlet pipeline. The sample inlet pipeline is connected to the sample dilution unit, and the sample outlet pipeline is connected to a waste liquid tank A; a differential pressure gauge is provided on the sample colorimetric cell of the colorimetric cell unit, and the differential pressure gauge monitors the differential pressure before and after the sample colorimetric cell is filled with the sample.

[0009] In some embodiments, the device is further provided with a gas purging assembly. The gas purging assembly includes a gas tank, a gas flow control unit, and a heating unit. The gas flow control unit is provided on the gas tank. The gas tank is connected to the sample inlet pipeline and the sample outlet pipeline through pipelines. The gas purging assembly purges the sample colorimetric cell to remove particulate impurities blocking the sample colorimetric cell; the gas tank is connected to the sample dilution tank through a purging gas pipeline, and a heating unit is provided on the purging gas pipeline. The gas purging assembly blows heated gas into the sample dilution tank to dry the solution remaining on the inner wall of the sample dilution tank.

[0010] In some embodiments, there are 5 standard colorimetric cells in the colorimetric cell unit. The heavy water concentrations of the 5 standard colorimetric cells are in the setting order shown in Figure 1, from top to bottom, the heavy water concentrations are 0%, 10%, 50%, 75%, and 100% respectively. The standard colorimetric cells are used to automatically calibrate the device.

[0011] In some embodiments, the temperature control unit controls the temperatures of the sample dilution unit and the colorimetric cell unit to be 25 ± 0.1 degrees.

[0012] In some embodiments, the optical path unit includes an infrared light source, an entrance slit, an exit slit, a plane mirror, and a grating. The infrared light source emits infrared light through the entrance slit. The infrared light enters the exit slit after being reflected by the grating and the plane mirror. The infrared light finally enters the colorimetric cell unit.

[0013] In some embodiments, the device is further provided with a negative pressure unit. The negative pressure unit is connected to the sample dilution tank through a pipeline, and the negative pressure unit is used to control the negative pressure of the other units accommodated.

[0014] In some embodiments, the detector unit includes a phototube and a control terminal, the control terminal is electrically connected to the phototube, the phototube absorbs infrared light transmitted from the heavy water sample in the sample colorimetric cell, and transmits the measurement data to the control terminal, the control terminal processes the data and obtains the measurement results; the control terminal is electrically connected to other units and automatically controls the functions of each unit; the device has a network port and has remote control and monitoring functions.

[0015] The implementation of the present invention has the following beneficial effects

[0016] The present invention provides an infrared spectroscopy heavy water concentration measuring instrument, which realizes the functions of automatically analyzing the heavy water concentration, controlling the heavy water concentration measurement temperature, and automatically calibrating the device using a standard sample solution. The device uses a gravimetric method to accurately dilute the sample, avoiding the problem of decreased instrument analysis accuracy within the heavy water concentration range of 2-20%. The device monitors the pressure difference before and after the colorimetric cell, and automatically backwashes to remove impurities such as clogging particles. The device comes with a standard heavy water solution sealed in the colorimetric cell, which is used to improve the pain points such as high environmental conditions, large concentration deviation, and short storage period of the standard solution when preparing the heavy water standard solution on site. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of an infrared spectrum heavy water concentration measuring instrument proposed in an embodiment of the present invention;

[0018] Figure 2 A schematic diagram of the appearance of an infrared spectrum heavy water concentration measuring instrument proposed in an embodiment of the present invention;

[0019] Figure 3 A schematic diagram of a colorimetric cell unit of an infrared spectroscopy heavy water concentration measuring instrument proposed in an embodiment of the present invention;

[0020] Figure 4 A schematic diagram of a dilution unit of an infrared spectrum heavy water concentration measuring instrument proposed in an embodiment of the present invention; Description of the drawings:

[0022] 1. Infrared light source; 2. Entrance slit; 3. Plane mirror A; 4. Grating; 5. Plane mirror B; 6. Exit slit; 7. Plane mirror C; 8. Waste liquid tank A; 9. Driving motor; 10. Standard colorimetric cell A; 11. Standard colorimetric cell B; 12. Standard colorimetric cell C; 13. Standard colorimetric cell D; 14. Standard colorimetric cell E; 15. Sample colorimetric cell; 16. Temperature controller A; 17. Differential pressure gauge; 18. Plunger pump A; 19. Sample dilution tank; 20. Temperature controller B; 21. Thermostatic chamber; 22. Valve A; 23. Valve B; 24. Plunger pump B; 25. Plunger pump C; 26. Valve C; 27. Weight measuring instrument; 28. Sample tank; 29. Light water tank; 30. Waste liquid tank B; 31. Gas tank; 32. Gas flow control unit; 33. Heating unit; 34. Photoelectric tube; 35. Control terminal; 36. Negative pressure unit; 37. Instrument component compartment; 38. Detector unit; 39. Dilution unit; 40. Sample inlet pipe; 41. Sample outlet pipe; 42. Transmission device; 43. Window; 44. Optical path unit; 45. Temperature control unit; 46. Colorimetric cell unit. Specific embodiments

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0024] As Figures 1 to 4As shown in the figure, the present invention provides an infrared spectroscopy heavy water concentration measuring instrument, which includes a sample dilution unit 39, a temperature control unit 45, an optical path unit 44, a colorimetric cell unit 46 and a detector unit 38. The sample dilution unit 39 is used to mix the heavy water sample with light water to adjust the concentration of the heavy water sample, and inject the mixed sample into the colorimetric cell unit 46. The sample dilution unit 39 includes a sample tank 28, a light water tank 29, a weighing instrument 27 and a sample dilution tank 19. The sample tank 28 and the light water tank 29 are respectively connected to the sample dilution tank 19 through pipelines. A plunger pump B 24 is provided on the pipeline connecting the sample tank 28 and the sample dilution tank 19, and a plunger pump C 25 is provided on the pipeline connecting the light water tank 29 and the sample dilution tank 19. The sample dilution tank 19 is placed in a constant temperature box 21, and the constant temperature box 21 controls the temperature through the temperature control unit 45. A weighing instrument 27 is provided on the sample dilution tank 19, and the weighing instrument 27 is used to accurately measure the weights of the heavy water sample and light water added into the sample dilution tank 19, precisely dilute the heavy water sample, and control the concentration of heavy water through this method to avoid the problem of the decline in the instrument analysis accuracy within the heavy water concentration range of 2-20%. The sample dilution tank 19 is connected to a waste liquid tank B 30 through a pipeline, and a valve C 26 is provided on this pipeline. The waste liquid tank B 30 is used to collect the waste liquid discharged from the sample dilution tank 19.

[0025] The colorimetric cell unit 46 includes a standard solution colorimetric cell and a sample colorimetric cell 15. The standard solution colorimetric cell and the sample colorimetric cell 15 are placed in parallel, and the distance between the standard solution colorimetric cell and the sample colorimetric cell 15 is 0.2 mm. The sample colorimetric cell 15 is respectively connected to a sample inlet pipeline 40 and a sample outlet pipeline 41. The sample inlet pipeline 40 is connected to the sample dilution unit 39, and a plunger pump A 18 is provided on the sample inlet pipeline 40. The sample outlet pipeline 41 is connected to a waste liquid tank A 8. A differential pressure gauge 17 is provided on the sample colorimetric cell 15 of the colorimetric cell unit 46. The differential pressure gauge 17 monitors the differential pressure before and after the sample colorimetric cell 15 is filled with the sample. When the differential pressure reaches a certain value, the gas purge assembly will be started for purging. There are a total of 5 standard colorimetric cells. The heavy water concentrations of the 5 standard colorimetric cells are in the order set in Figure 1 from top to bottom. The heavy water concentration of the standard colorimetric cell A 10 is 0% respectively, the heavy water concentration of the standard colorimetric cell B 11 is 10% respectively, the heavy water concentration of the standard colorimetric cell C 12 is 50% respectively, the heavy water concentration of the standard colorimetric cell D 13 is 75% respectively, and the heavy water concentration of the standard colorimetric cell E 14 is 100% respectively. The standard colorimetric cell is used to automatically calibrate the device. The colorimetric cell unit 46 realizes the switching between the sample colorimetric cell 15 and the heavy water standard concentration colorimetric cell through a drive motor 9 driving a transmission device 42. The colorimetric cell unit 46 is also provided with a window 43, and infrared light enters the colorimetric cell unit 46 through the window 43.

[0026] The temperature control unit 45 includes a temperature controller A16 and a temperature controller B20. The temperature controller A16 is used to control the temperature of the colorimetric cell unit 46, and the temperature controller B20 is used to control the temperature of the sample dilution unit 39. The temperature control unit 45 controls the temperature of the sample dilution unit 39 and the colorimetric cell unit 46 to be 25±0.1 degrees.

[0027] The optical path unit 44 is used to emit infrared light to the sample colorimetric cell 15. The optical path unit 44 includes an infrared light source 1, an entrance slit 2, an exit slit 6, a plane mirror A3, a plane mirror B5, a plane mirror C7 and a grating 4. The infrared light source 1 emits infrared light through the entrance slit 2. The infrared light is reflected by the plane mirrors A3 and B5 and enters the grating 4. The infrared light is emitted from the grating 4 and enters the exit slit 6 after being reflected by the plane mirror C7. The infrared light is finally emitted into the window 43 of the colorimetric cell unit 46.

[0028] The detector unit 38 is electrically connected to other units, and is used to control the functions of other units and detect the concentration of the heavy water sample in the sample colorimetric cell 15. The detector unit 38 includes a phototube 34 and a control terminal 35, and the control terminal 35 is electrically connected to the phototube 34. The phototube 34 absorbs infrared light transmitted from the heavy water sample in the sample colorimetric cell 15, and transmits the measurement data to the control terminal 35, and the control terminal 35 processes the data and obtains the measurement result; the control terminal 35 is electrically connected to other units and automatically controls the functions of each unit; the device has a network port and has remote control and monitoring functions.

[0029] The present invention provides an infrared spectroscopy heavy water concentration measuring instrument, which realizes the functions of automatically analyzing the heavy water concentration, controlling the heavy water concentration measurement temperature, and automatically calibrating the device using a standard sample solution. The device uses a gravimetric method to accurately dilute the sample, avoiding the problem of decreased instrument analysis accuracy within the heavy water concentration range of 2-20%. The device comes with a standard heavy water solution sealed in a colorimetric cell, which is used to improve the pain points of high environmental conditions, large concentration deviation, and short storage period of the standard solution when preparing the heavy water standard solution on site.

[0030] In some embodiments, the device is further provided with a negative pressure unit 36, which is connected to the sample dilution tank 19 through a pipeline, and a valve A22 is provided on the connecting pipeline. The negative pressure unit 36 ​​is used to control the negative pressure of the instrument component compartment 37, thereby ensuring that when the heavy water sample evaporates or leaks due to a malfunction, the heavy water sample vapor will not leak into the environment.

[0031] In some embodiments, the device is further provided with a gas purging assembly. The gas purging assembly includes a gas tank 31, a gas flow control unit 32, and a heating unit 33. The gas flow control unit 32 is provided on the gas tank 31. The gas tank 31 is connected to the sample inlet pipe 40 and the sample outlet pipe 41 through pipelines. The gas purging assembly purges the sample colorimetric cell 15 to remove particulate impurities that block the sample colorimetric cell 15. The gas tank 31 is connected to the sample dilution tank 19 through a purging gas pipeline. The heating unit 33 and a valve B23 are provided on the purging gas pipeline. After the analysis of the heavy water sample is completed, the sample in the sample dilution tank 19 is discharged into the waste liquid tank B30. The gas in the gas tank 31 enters the sample dilution tank 19 after being heated by the heating unit 33 to dry the solution remaining on the inner wall of the sample dilution tank 19, ensuring that the dilution of the next sample will not be interfered. The device monitors the pressure difference before and after the colorimetric cell and automatically performs backwashing to remove impurities such as blocked particles.

[0032] The present invention provides an infrared spectroscopy heavy water concentration measuring instrument. The specific implementation method of the device is as follows:

[0033] The dilution unit 39 injects the heavy water sample in the sample tank 28 and the light water in the light water tank 29 into the sample dilution tank 19, and controls the weights of the heavy water sample and the light water through the weight measuring instrument 27 for precise dilution, avoiding the range of heavy water concentration from 2% to 20%.

[0034] Next, the sample dilution tank 19 injects the mixed heavy water sample into the sample colorimetric cell 15. The optical path unit 44 emits infrared light to pass through the window 43 of the colorimetric cell unit 46 to irradiate the mixed heavy water sample. The phototube 34 absorbs the infrared light transmitted from the mixed heavy water sample and transmits the measurement data to the control terminal 35. The control terminal 35 processes the test data to obtain the measurement result of the heavy water concentration.

[0035] After the measurement is completed, the remaining sample solution in the sample colorimetric cell 15 is discharged into the waste liquid tank A8, and the remaining sample solution in the sample dilution tank 19 is discharged into the waste liquid tank B30. The gas purging assembly blows heated gas into the sample dilution tank 19 to dry the solution remaining on the inner wall of the sample dilution tank 19. At the same time, the differential pressure gauge 17 monitors the pressure difference before and after the measurement of the sample colorimetric cell 15 to determine whether it is necessary to start the gas purging assembly to purge the sample colorimetric cell 15.

[0036] The above embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention should be subject to the appended claims.

Claims

1. An infrared spectrum heavy water concentration measuring instrument, characterized in that: The measuring instrument comprises a sample dilution unit, a temperature control unit, an optical path unit, a colorimetric cell unit, and a detector unit. The sample dilution unit mixes a heavy water sample with light water to adjust the concentration of the heavy water sample, and injects the mixed sample into the colorimetric cell unit; the colorimetric cell unit comprises a standard solution colorimetric cell and a sample colorimetric cell, and the sample colorimetric cell performs heavy water concentration detection; the temperature control unit controls the temperature of the sample dilution unit and the colorimetric cell unit; the optical path unit emits infrared light to the sample colorimetric cell; the detector unit is electrically connected to other units, and the detector unit controls the functions of other units and detects the concentration of the heavy water sample in the sample colorimetric cell.

2. The infrared spectrum heavy water concentration measuring instrument according to claim 1, characterized in that: The sample dilution unit comprises a sample tank, a light water tank, a weight measuring instrument and a sample dilution tank. The sample tank and the light water tank are respectively connected to the sample dilution tank through pipelines. The sample dilution tank is provided with the weight measuring instrument. The weight measuring instrument accurately measures the weight of the heavy water sample and the light water added into the sample dilution tank, and accurately dilutes the heavy water sample.

3. An infrared spectrum heavy water concentration measuring instrument according to claim 2, characterized in that, The sample dilution tank of the sample dilution unit is connected to a waste liquid tank B, and the waste liquid tank B is used to collect waste liquid discharged from the sample dilution tank; a plunger pump B is provided on the pipeline connecting the sample tank and the sample dilution tank, and a plunger pump C is provided on the pipeline connecting the light water tank and the sample dilution tank.

4. The infrared spectrum heavy water concentration measuring instrument according to claim 3, characterized in that: The sample colorimetric cell is connected to a sample inlet pipe and a sample outlet pipe respectively, the sample inlet pipe is connected to the sample dilution unit, and the sample outlet pipe is connected to a waste liquid tank A; the sample colorimetric cell of the colorimetric cell unit is provided with a differential pressure gauge, and the differential pressure gauge monitors the pressure difference before and after the sample is filled in the sample colorimetric cell.

5. The infrared spectrum heavy water concentration measuring instrument according to claim 4, characterized in that: The device is also provided with a gas purge component, which includes a gas tank, a gas flow control unit and a heating unit. The gas tank is provided with the gas flow control unit, and the gas tank is connected to the sample inlet pipe and the sample outlet pipe through a pipe. The gas purge component purges the sample colorimetric cell to remove particulate impurities that block the sample colorimetric cell; the gas tank is connected to the sample dilution tank through a purge gas pipeline, and the heating unit is provided on the purge gas pipeline. The gas purge component blows heated gas into the sample dilution tank to dry the solution remaining on the tank wall in the sample dilution tank.

6. The infrared spectrum heavy water concentration measuring instrument according to claim 5, characterized in that: The colorimetric cell unit is provided with 5 standard colorimetric cells, the heavy water concentrations of the standard colorimetric cells are 0%, 10%, 50%, 75% and 100% respectively, and the standard colorimetric cells are used for automatic calibration of the measuring instrument.

7. The infrared spectrum heavy water concentration measuring instrument according to claim 6, characterized in that: The temperature control unit controls the temperature of the sample dilution unit and the colorimetric cell unit to be 25±0.1 degrees.

8. The infrared spectrum heavy water concentration measuring instrument according to claim 7, characterized in that: The optical path unit includes an infrared light source, an entrance slit, an exit slit, a plane mirror and a grating. The infrared light source emits infrared light through the entrance slit, the infrared light enters the exit slit after being reflected by the grating and the plane mirror, and the infrared light finally enters the colorimetric cell unit.

9. The infrared spectrum heavy water concentration measuring instrument according to claim 8, characterized in that: The device is also provided with a negative pressure unit, which is connected to the sample dilution tank through a pipeline, and is used to control the negative pressure of other units.

10. The infrared spectrum heavy water concentration measuring instrument according to claim 9, characterized in that: The detector unit includes a phototube and a control terminal, the control terminal is electrically connected to the phototube, the phototube absorbs infrared light transmitted from the heavy water sample in the sample colorimetric cell, and transmits measurement data to the control terminal, the control terminal processes the data and obtains measurement results; the control terminal is electrically connected to other units and automatically controls the functions of each unit; the device is equipped with a network port and has remote control and monitoring functions.

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