Pretreatment equipment for measuring and analyzing C-14 in environmental water sample

Abstract

The invention relates to the technical field of environmental water sample detection, and provides pretreatment equipment for measuring and analyzing C-14 in an environmental water sample, the pretreatment equipment comprises a reaction container, a condensing device, a drying device and a collecting device, the reaction container comprises a reaction cavity, a liquid outlet and a gas outlet, and the liquid outlet and the gas outlet are both communicated with the reaction cavity; the condensing device comprises a condensing cavity, a condensing inlet, a condensing outlet and a cooling cavity, the condensing inlet and the condensing outlet are both communicated with the condensing cavity, the condensing inlet is communicated with the air outlet, the cooling cavity is used for circulating cooling fluid and isolated from the condensing cavity, and the condensing cavity is located in the cooling cavity; the drying device is communicated with the condensation outlet and is used for absorbing water vapor; the collecting device is communicated with the drying device, and absorption liquid is contained in the collecting device and used for absorbing carbon dioxide from the reaction cavity. The pretreatment equipment can be used for pretreating a carbon-containing compound in an environmental water sample, and the requirement for measuring C-14 in the environmental water sample, especially in a surrounding environmental water body of a nuclear power station, is met.

Description

Technical Field

[0001] The present application relates to the technical field of environmental water sample detection, and in particular to a pretreatment device for measuring and analyzing C-14 in environmental water samples. Background Art

[0002] This section is intended to provide a background or context to the embodiments of the present application. No description herein is admitted to be prior art by virtue of its inclusion in this section.

[0003] With the continuous development of the nuclear industry, a large amount of C-14 is discharged into the surrounding environment during the operation of nuclear facilities. Therefore, it is necessary to increase the monitoring of the environment, especially C-14 in the surrounding environment of nuclear power plants. In occupational health monitoring and workplace radiation hazard factor monitoring, the monitoring of C-14 in the working environment and in the body has received more and more attention. According to the Technical Specifications for Radiation Environment Monitoring (HJ 61-2021), the Technical Specifications for Background Survey of Radiation Environment Before Operation of Nuclear Power Plants (HJ 969-2018), the Regulations on Environmental Radiation Protection of Nuclear Power Plants (GB6249-2011) and the Technical Requirements for Discharge of Radioactive Liquid Effluents from Nuclear Power Plants (GB14587-2011), during the operation of nuclear facilities, C-14 in the environmental medium is an important nuclide to be monitored. Among them, water bodies, as part of the environmental medium, must also carry out corresponding monitoring and analysis of C-14 in water.

[0004] At present, the measurement method for C-14 mainly uses liquid scintillation measurement, which requires pretreatment of carbon-containing compounds in water. The pretreatment method for TOC (Total Organic Carbon) in water mainly uses wet oxidation and high-temperature combustion oxidation. Both methods can convert inorganic carbon and organic carbon in water into carbon dioxide, and use alkaline solution to absorb carbon dioxide to generate calcium carbonate powder, thereby achieving pretreatment of carbon-containing compounds. Then, an appropriate amount of calcium carbonate powder is added with scintillation liquid for liquid scintillation measurement.

[0005] In the related art, liquid scintillation measurement of C-14 is performed by wet oxidation analyzers and high-temperature combustion oxidation analyzers. The disadvantages of wet oxidation analyzers are long analysis time, low analysis sample volume, and difficulty in analyzing high-concentration TOC. The wet oxidation analyzer has a low analysis sample volume and is only suitable for small-volume water samples. The content of C-14 in environmental water samples is low, and it is difficult for wet oxidation analyzers to detect C-14 in environmental water samples. The disadvantage of using high-temperature combustion oxidation is that salt melts at high temperatures, corrodes the catalyst and the combustion tube, the catalyst will be poisoned and fail, the oxidation temperature is difficult to control, the oxidation is incomplete, and it is not easy to eliminate the memory effect, resulting in a high background value. At the same time, the water vapor generated at high temperature will block the infrared rays inside the detector, making it unable to work normally. Therefore, the above two analyzers measure and analyze C-14 in small volumes and nuclear waste liquids. The existing wet oxidation analyzers and high-temperature combustion oxidation analyzers cannot meet the measurement requirements of C-14 in environmental water samples. Summary of the invention

[0006] In view of this, the embodiments of the present application hope to provide a pretreatment device for measuring and analyzing C-14 in environmental water samples, which can pretreat carbon-containing compounds in environmental water samples to meet the measurement requirements of C-14 in environmental water samples.

[0007] The present application embodiment provides a pretreatment device for measuring and analyzing C-14 in environmental water samples, including:

[0008] A reaction container, comprising a reaction chamber, a liquid outlet and a gas outlet, wherein the liquid outlet and the gas outlet are both connected to the reaction chamber;

[0009] A condensation device, comprising a condensation chamber, a condensation inlet, a condensation outlet and a cooling chamber, wherein the condensation inlet and the condensation outlet are both connected to the condensation chamber, the condensation inlet is connected to the air outlet, the cooling chamber is used to circulate a cooling fluid, the cooling chamber is isolated from the condensation chamber, and the condensation chamber is located in the cooling chamber;

[0010] A drying device, connected to the condensation outlet, and used to absorb water vapor;

[0011] A collecting device is communicated with the drying device, wherein the collecting device contains an absorption liquid, and the absorption liquid is used to absorb carbon dioxide from the reaction chamber.

[0012] In some embodiments, the volume of the reaction chamber is not less than 50L.

[0013] In some embodiments, the reaction container includes a liquid inlet connected to the reaction chamber, and the liquid inlet is used to introduce environmental water samples and treatment reagents into the reaction chamber.

[0014] In some embodiments, the reaction container includes a gas inlet connected to the reaction chamber, and the gas inlet is used to introduce a carrier gas into the reaction chamber.

[0015] In some embodiments, the pretreatment equipment includes a cold bath circulation device, and the inlet and outlet of the cooling chamber are both connected to the cold bath circulation device, and the cold bath circulation device is used to introduce a circulating cooling fluid into the cooling chamber.

[0016] In some embodiments, the cold bath circulation device is disposed on one side of the reaction container along a first direction, and the first direction is perpendicular to the up-down direction.

[0017] In some embodiments, the pretreatment equipment includes a warm bath circulation device, the reaction container includes a heating chamber, the reaction chamber is located in the heating chamber, and the heating chamber and the reaction chamber are isolated, the inlet and outlet of the heating chamber are connected to the warm bath circulation device, and the warm bath circulation device is used to introduce a circulating heating fluid into the heating chamber.

[0018] In some embodiments, the temperature bath circulation device is disposed on one side of the reaction container along a first direction, and the first direction is perpendicular to the up-down direction.

[0019] In some embodiments, the pretreatment equipment includes a frame and a walking mechanism, the reaction container, the condensing device, the drying device and the collecting device are all arranged on the frame, and the walking mechanism is arranged at the bottom of the frame.

[0020] In some embodiments, the condensing device is located above the reaction container; and / or the drying device is higher than the collecting device.

[0021] The pretreatment equipment provided in the embodiment of the present application condenses the gaseous substances discharged from the gas outlet through the condensation device to reduce the water content of the gaseous substances. The liquid water and treatment reagents after condensation can flow back to the reaction chamber through the condensation inlet to achieve the purpose of recycling the treatment reagents and reducing resource waste. The drying device can further absorb water vapor, further reduce the water content of the gaseous substances, and improve the reaction efficiency of the absorption liquid. The reaction container can hold a large volume of environmental water samples, and can pre-treat carbon-containing compounds in environmental water samples to meet the measurement requirements of environmental water samples, especially C-14 in environmental water bodies around nuclear power plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the structure of a pretreatment device used for measuring and analyzing C-14 in environmental water samples in some embodiments of the present application;

[0023] Figure 2 for Figure 1 a schematic diagram of another view of the structure shown;

[0024] Figure 3 This is a schematic diagram of the structure of a reaction container, a condensing device, a drying device and a collecting device in some embodiments of the present application;

[0025] Figure 4 for Figure 3 a schematic diagram of another view of the structure shown;

[0026] Figure 5 This is a partial structural schematic diagram of a reaction container and a condensing device in some embodiments of the present application;

[0027] Figure 6 for Figure 5 a schematic diagram of another view of the structure shown;

[0028] Figure 7 for Figure 6 Schematic diagram of the cross-section along the AA direction.

[0029] Description of Reference Numerals

[0030] 1. Reaction container; 1a. Reaction chamber; 1b. Liquid outlet; 1c. Gas outlet; 1d. Liquid inlet; 1e. Gas inlet; 1f. Heating chamber; 1fa. Inlet of heating chamber 1f; 1fb. Outlet of heating chamber 1f; 11. Inner cylinder; 12. Outer cylinder; 2. Condensation device; 2a. Condensation chamber; 2b. Condensation inlet; 2c. Condensation outlet; 2d. Cooling chamber; 2da. Inlet of cooling chamber 2d; 2db. Outlet of cooling chamber 2d; 2 1. Condenser; 22. Shell; 3. Drying device; 3a. Inlet; 3b. Exhaust port; 4. Collecting device; 41. Cover; 42. Bottle body; 5. Cold bath circulation device; 6. Warm bath circulation device; 7. Frame; 71. Frame; 72. Partition; 8. Traveling mechanism; 9. Liquid pump; 10. Bending tube; 101. Planar bending section; 1011. Second pipe section; 102. First pipe section; 20. Temperature detection element; 30. Pressure detection element. DETAILED DESCRIPTION

[0031] The following is a further detailed description of the implementation of the present application in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application but cannot be used to limit the scope of the present application.

[0032] The various specific technical features and embodiments described in the specific implementation methods can be combined in any suitable manner without contradiction. For example, different implementation methods can be formed by combining different specific technical features / embodiments. In order to avoid unnecessary repetition, the various possible combinations of the specific technical features / embodiments in this application are no longer described separately. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. The application is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0033] It should be noted that the "multiple" in the embodiments of the present application includes two and more than two. Up refers to the direction toward the sky, and down refers to the direction opposite to up.

[0034] See also Figure 1 An embodiment of the present application provides a pretreatment device for measuring and analyzing C-14 in environmental water samples, the pretreatment device comprising a reaction container 1, a condensing device 2, a drying device 3 and a collecting device 4.

[0035] See also Figures 4 to 7 The reaction container 1 includes a reaction chamber 1a, a liquid outlet 1b and a gas outlet 1c, and the liquid outlet 1b and the gas outlet 1c are both connected to the reaction chamber 1a. Inorganic carbon and organic carbon in the environmental water sample react in the reaction chamber 1a to generate carbon dioxide.

[0036] The liquid outlet 1b is used to discharge the liquid substance remaining after the reaction, and the gas outlet 1c is used to discharge the gaseous substance containing carbon dioxide generated by the reaction.

[0037] See also Figures 1 to 7 The condensation device 2 includes a condensation chamber 2a, a condensation inlet 2b, a condensation outlet 2c and a cooling chamber 2d. The condensation inlet 2b and the condensation outlet 2c are both connected to the condensation chamber 2a. The condensation inlet 2b is connected to the gas outlet 1c. The cooling chamber 2d is used to circulate the cooling fluid. The cooling chamber 2d is isolated from the condensation chamber 2a. The condensation chamber 2a is located in the cooling chamber 2d. In other words, the cooling chamber 2d is wrapped outside the condensation chamber 2a.

[0038] The condensation inlet 2b is communicated with the gas outlet 1c, and the gaseous substances in the reaction chamber 1a enter the condensation chamber 2a through the gas outlet 1c and the condensation inlet 2b.

[0039] The cooling chamber 2d is isolated from the condensing chamber 2a, that is, the cooling chamber 2d and the condensing chamber 2a are not connected to each other, the cooling fluid in the cooling chamber 2d will not enter the condensing chamber 2a, and the substances in the condensing chamber 2a will not enter the cooling chamber 2d.

[0040] The cooling fluid can absorb the heat of the gaseous substances in the condensation chamber 2a, so that part of the gaseous substances is condensed into liquid.

[0041] The drying device 3 is connected to the condensation outlet 2c, and the drying device 3 is used to absorb water vapor. The drying device 3 is located downstream of the condensation device 2. The gaseous substances from the reaction chamber 1a are condensed by the condensation device 2 and then enter the drying device 3 through the condensation outlet 2c. The drying device 3 is used to reduce the water content of the gaseous substances.

[0042] The collecting device 4 is connected to the drying device 3. The collecting device 4 contains an absorption liquid, which is used to absorb carbon dioxide from the reaction chamber 1a. Specifically, the absorption liquid can react with carbon dioxide to generate carbon-containing precipitates.

[0043] Exemplarily, the absorption liquid can be an inorganic base or an organic base.

[0044] C-14, or carbon-14, is a radioactive isotope of carbon.

[0045] Environmental water samples are samples obtained from environmental water bodies.

[0046] The pretreatment equipment provided in the embodiment of the present application converts organic carbon and inorganic carbon in the environmental water sample into a carbonaceous precipitate by a wet oxidation method, thereby completing the pretreatment of the environmental water sample. The carbonaceous precipitate can be subsequently measured and analyzed for C-14 by a liquid scintillation measurement method. For example, the carbonaceous precipitate can react with a scintillation liquid for liquid scintillation measurement to achieve C-14 measurement and analysis.

[0047] Exemplarily, both the environmental water sample and the treatment reagent enter the reaction chamber 1a, in which the carbon-containing compounds in the environmental water sample react with the treatment reagent to generate a gaseous substance containing carbon dioxide, and an aqueous solution after the carbon-containing compounds are removed, etc. The gaseous substance containing carbon dioxide enters the condensation chamber 2a through the gas outlet 1c and the condensation inlet 2b, and the gaseous substance containing carbon dioxide is condensed by the cooling fluid, and at least part of the water vapor and the treatment reagent are condensed and separated, and the condensed gaseous substance containing carbon dioxide enters the drying device 3 for further dehydration, and the dehydrated gaseous substance containing carbon dioxide enters the collecting device 4, in which the gaseous substance containing carbon dioxide reacts with the absorption liquid to generate a carbon-containing precipitate, completing the pretreatment of the environmental water sample.

[0048] Since the reaction temperature in the reaction chamber 1a is relatively high, the gaseous substance is likely to contain water vapor and gaseous treatment reagents. If the water vapor and gaseous treatment reagents enter the collection device 4, it will affect the reaction efficiency of carbon dioxide and the absorption liquid, and will also reduce the content of the treatment reagents in the reaction chamber 1a, resulting in waste of resources. Therefore, the gaseous substance is condensed by the condensation device 2 to reduce the water content of the gaseous substance. The liquid water and treatment reagents after condensation can flow back to the reaction chamber 1a through the condensation inlet 2b, so as to achieve the purpose of recovering the treatment reagents and reducing resource waste. The drying device 3 can further absorb water vapor, further reduce the water content of the gaseous substance, and improve the reaction efficiency of the absorption liquid.

[0049] It is understood that C-14 is an isotope of carbon and can exist in the form of organic carbon-14 and inorganic carbon-14. In this way, the generated carbon dioxide and carbonaceous precipitates both contain C-14.

[0050] Illustratively, the pretreatment equipment provided in the embodiment of the present application has an activity concentration detection limit of 0.65 mBq / L (millibecquerel per liter) for C-14, while the activity concentration of C-14 in environmental water samples is on the order of 1 mBq / L. Therefore, the detection limit of the pretreatment equipment provided in the present application is lower than the activity concentration of C-14 in environmental water samples, and the pretreatment equipment provided in the present application is suitable for activity concentration analysis of C-14 in environmental water samples.

[0051] The pretreatment equipment provided in the embodiment of the present application condenses the gaseous substances discharged from the gas outlet 1c through the condensation device 2 to reduce the water content of the gaseous substances. The liquid water and treatment reagents after condensation can flow back to the reaction chamber 1a through the condensation inlet 2b, so as to achieve the purpose of recycling the treatment reagents and reducing resource waste. The drying device 3 can further absorb water vapor, further reduce the water content of the gaseous substances, and improve the reaction efficiency of the absorption liquid. The reaction container 1 can hold a large volume of environmental water samples to meet the measurement requirements of the activity concentration of C-14 in environmental water bodies, especially in environmental water bodies around nuclear power plants.

[0052] For some examples, see Figure 7 , the volume of the reaction chamber 1a is not less than 50 L. Exemplarily, the volume of the reaction chamber 1a can be 50 L, 60 L, 80 L, 100 L, 120 L, 150 L, 180 L or 200 L, etc. The volume of the reaction chamber 1a is relatively large, and the volume of the environmental water sample that can be contained in the reaction chamber 1a can be large to adapt to the pretreatment of large-volume water samples, and can enrich a suitable amount of carbonaceous precipitates from large-volume water samples to meet the detection requirements of C-14 in environmental water samples.

[0053] For some examples, see Figure 3 and Figure 7The reaction container 1 includes a liquid inlet 1d connected to the reaction chamber 1a, and the liquid inlet 1d is used to introduce environmental water samples and treatment reagents into the reaction chamber 1a.

[0054] Environmental water samples refer to water samples taken from environmental water bodies. Environmental water samples contain organic and inorganic carbon.

[0055] The process reagent is a reagent used to chemically react with carbon-containing compounds to generate carbon dioxide.

[0056] Treatment agents include, but are not limited to, acids and persulfate oxidants, etc. The acid may include phosphoric acid or sulfuric acid.

[0057] Organic carbon, inorganic carbon and persulfate oxidant react under acidic conditions to produce carbon dioxide.

[0058] In this embodiment, the environmental water sample and the treatment reagent are both in liquid form, and both the environmental water sample and the treatment reagent can enter the reaction chamber 1a through the liquid inlet 1d, thereby reducing the opening of the reaction container 1 and improving the sealing reliability of the reaction container 1.

[0059] For some examples, see Figures 1 to 3 The pretreatment equipment includes a liquid pump 9, which is connected to the liquid inlet 1d. The liquid pump 9 pumps the environmental water sample and the treatment reagent into the reaction chamber 1a.

[0060] Exemplarily, a liquid inlet pipe is connected between the liquid pump 9 and the liquid inlet 1d, the environmental water sample can be contained in the first tank body, and the treatment reagents can be placed in multiple second tank bodies respectively. The liquid pump 9 can connect the first tank body and the multiple second tank bodies through a pipeline, and suck the environmental water sample and the treatment reagent from the first tank body and the multiple second tank bodies according to needs, and then send them into the liquid inlet 1d.

[0061] In this embodiment, the environmental water sample and the treatment reagent are pumped by the liquid pump 9, which can avoid the error caused by manual liquid addition, improve the degree of automation and accuracy, and also improve the injection rate.

[0062] The type of the liquid pump 9 is not limited. Exemplarily, the liquid pump 9 may be a peristaltic pump.

[0063] For some examples, see Figure 5 and Figure 7 The reaction container 1 includes a gas inlet 1e connected to the reaction chamber 1a, and the gas inlet 1e is used to introduce a carrier gas into the reaction chamber 1a.

[0064] The carrier gas can be used to carry the gaseous substances generated in the reaction chamber 1a.

[0065] The carrier gas does not participate in the chemical reaction and can be an inactive gas, such as nitrogen.

[0066] In this embodiment, the carrier gas can carry the gaseous substances such as carbon dioxide generated in the reaction chamber 1a into the condensation chamber 2a, the drying device 3 and the collecting device 4, etc., to increase the flow rate of the gaseous substances, save processing time and shorten the duration.

[0067] In some embodiments, the carrier gas can also be used to detect the airtightness of the pre-processing equipment.

[0068] For some examples, see Figures 1 to 7 The pretreatment equipment includes a cold bath circulation device 5, and the inlet 2da and the outlet 2db of the cooling chamber 2d are both connected to the cold bath circulation device 5, and the cold bath circulation device 5 is used to introduce a circulating cooling fluid into the cooling chamber 2d.

[0069] The cooling bath circulation device 5 can reduce the temperature of the cooling fluid and drive the cooling fluid to flow.

[0070] Exemplarily, the cold bath circulation device 5 delivers a cooling fluid with a relatively low temperature into the cooling chamber 2d through the inlet 2da of the cooling chamber 2d. The temperature of the cooling fluid in the cooling chamber 2d is lower than the temperature of the gaseous substance in the condensation chamber 2a. The cooling fluid in the cooling chamber 2d absorbs the heat of the gaseous substance in the condensation chamber 2a. Part of the gaseous substance in the condensation chamber 2a is cooled and condensed into liquid. The cooling fluid after absorbing heat flows back to the cold bath circulation device 5 through the outlet 2db of the cooling chamber 2d. The cold bath circulation device 5 then lowers the temperature of the cooling fluid and delivers it into the cooling chamber 2d through the inlet 2da of the cooling chamber 2d again. This cycle is repeated to achieve continuous condensation of the gaseous substance in the condensation chamber 2a.

[0071] In this embodiment, the cold bath circulation device 5 can reduce the temperature of the cooling fluid and drive the cooling fluid to flow, thereby providing the condensing device 2 with a relatively low temperature and circulating cooling fluid, and continuously reducing the temperature of the gaseous substance in the condensing chamber 2a.

[0072] It can be understood that the temperature of the cooling fluid is lower than the temperature of the gaseous substance in the condensation chamber 2a, and the cooling fluid can absorb heat.

[0073] The cooling fluid is a flowable fluid, and the cooling fluid may be in a gaseous state or a liquid state. Exemplarily, the cooling fluid includes but is not limited to oily substances, such as silicone oil.

[0074] For some examples, see Figure 1 and Figure 2 The cold bath circulation device 5 is arranged on one side of the reaction container 1 along a first direction, and the first direction is perpendicular to the up-down direction.

[0075] In this embodiment, the cold bath circulation device 5 is arranged on one side of the reaction container 1 along the first direction, that is, the cold bath circulation device 5 and the reaction container 1 are arranged side by side approximately along the first direction. The masses of both the cold bath circulation device 5 and the reaction container 1 are relatively large. Such an arrangement is conducive to lowering the center of gravity of the pretreatment equipment, so that the pretreatment equipment can be placed more stably and the risk of tipping is reduced.

[0076] The cold bath circulation device 5 may include an icooler-3040 refrigeration device.

[0077] For some examples, see Figures 1 to 7 The pretreatment equipment includes a warm bath circulation device 6, the reaction vessel 1 includes a heating chamber 1f, the reaction chamber 1a is located in the heating chamber 1f, and the heating chamber 1f and the reaction chamber 1a are isolated, the inlet 1fa and the outlet 1fb of the heating chamber 1f are both connected to the warm bath circulation device 6, and the warm bath circulation device 6 is used to introduce a circulating heating fluid into the heating chamber 1f.

[0078] The reaction chamber 1a is located in the heating chamber 1f, that is, the heating chamber 1f is wrapped around the outside of the reaction chamber 1a, and the substances in the reaction chamber 1a can absorb the heat of the heating fluid in the heating chamber 1f. The heating fluid is used to heat the environmental water sample and the treatment reagent in the reaction chamber 1a, so that the substances in the reaction chamber 1a are maintained at the reaction temperature.

[0079] The heating chamber 1f and the reaction chamber 1a are isolated, that is, the heating chamber 1f and the reaction chamber 1a are not connected to each other, the heating fluid in the heating chamber 1f will not enter the reaction chamber 1a, and the substance in the reaction chamber 1a will not enter the heating chamber 1f.

[0080] The warm bath circulation device 6 can increase the temperature of the heating fluid and drive the heating fluid to flow.

[0081] Exemplarily, the warm bath circulation device 6 delivers a heating fluid with a relatively high temperature into the heating chamber 1f through the inlet 1fa of the heating chamber 1f. The temperature of the heating fluid in the heating chamber 1f is higher than the temperature of the substance in the reaction chamber 1a. The heating fluid in the heating chamber 1f releases heat to the substance in the reaction chamber 1a. The substance in the reaction chamber 1a absorbs heat and undergoes a chemical reaction. The heating fluid after releasing heat flows back to the warm bath circulation device 6 through the outlet 1fb of the heating chamber 1f. The warm bath circulation device 6 then increases the temperature of the heating fluid and delivers it into the heating chamber 1f through the inlet 1fa of the heating chamber 1f again. This cycle is repeated so that the substance in the reaction chamber 1a is maintained at the reaction temperature.

[0082] In this embodiment, the warm bath circulation device 6 can increase the temperature of the heating fluid and drive the heating fluid to flow, thereby providing the reaction container 1 with a relatively high temperature and circulating heating fluid to maintain the reaction temperature required for the chemical reaction between the environmental water sample and the treatment reagent. The reaction chamber 1a is located in the heating chamber 1f and is heated by the heating fluid. The heating uniformity is good, which is conducive to the substances at various positions in the reaction chamber 1a to be stably maintained at the reaction temperature.

[0083] The bath circulation device 6 may include a Lepto DCC75HH12 heating device.

[0084] It can be understood that the temperature of the heating fluid is higher than the temperature of the substance in the reaction chamber 1a, and the heating fluid can release heat.

[0085] The heating fluid is a flowable fluid, and the heating fluid can be in gaseous or liquid state. The heating fluid can be the same as or different from the cooling fluid. Exemplarily, the heating fluid includes but is not limited to oily substances, such as silicone oil.

[0086] For some examples, see Figure 7 The reaction vessel 1 comprises an inner cylinder 11 and an outer cylinder 12. The outer cylinder 12 is sleeved outside the inner cylinder 11. The space inside the inner cylinder 11 is a reaction chamber 1a, and the space between the outer cylinder 12 and the inner cylinder 11 is a heating chamber 1f. The reaction vessel 1 adopts a double-layer cylinder.

[0087] For some examples, see Figure 7 Two connecting pipes can be connected to the outer cylinder 12, and both connecting pipes are connected to the heating chamber 1f. The two connecting pipes serve as the inlet 1fa and the outlet 1fb of the heating chamber 1f respectively.

[0088] The inner cylinder 11 may be substantially in the shape of a hollow column. For example, the inner cylinder 11 may be substantially in the shape of a hollow cylinder.

[0089] The outer cylinder 12 may be substantially in the shape of a hollow column. For example, the outer cylinder 12 may be substantially in the shape of a hollow cylinder.

[0090] For some examples, see Figure 4 and Figure 7 The inlet 1fa of the heating chamber 1f may be located at the bottom of the reaction vessel 1, the outlet 1fb of the heating chamber 1f may be located on the circumferential surface of the reaction vessel 1, and the height of the outlet 1fb of the heating chamber 1f is higher than the inlet 1fa of the heating chamber 1f.

[0091] For example, the inlet 1fa of the heating chamber 1f may be located at the bottom of the outer cylinder 12 , and the outlet 1fb of the heating chamber 1f may be located at the circumferential surface of the outer cylinder 12 .

[0092] In this embodiment, the heating fluid from the inlet 1fa of the heating chamber 1f can contact the environmental water sample and the treatment reagent at the bottom of the reaction chamber 1a as soon as possible, so that the environmental water sample and the treatment reagent are quickly heated and kept warm.

[0093] In some embodiments, the reaction container 1 may be made of high borosilicate glass. For example, both the outer cylinder 12 and the inner cylinder 11 may be made of high borosilicate glass. High borosilicate glass has the characteristics of high temperature resistance and acid resistance.

[0094] For some examples, see Figure 1 and Figure 2 The warm bath circulation device 6 is arranged on one side of the reaction container 1 along a first direction, and the first direction is perpendicular to the up-down direction.

[0095] In this embodiment, the warm bath circulation device 6 is arranged on one side of the reaction container 1 along the first direction, that is, the warm bath circulation device 6 and the reaction container 1 are arranged side by side roughly along the first direction. The mass of both the warm bath circulation device 6 and the reaction container 1 is relatively large. Such an arrangement is conducive to lowering the center of gravity of the pretreatment equipment, and the pretreatment equipment can be placed more stably.

[0096] For some examples, see Figure 1 and Figure 2 The warm bath circulation device 6 and the cold bath circulation device 5 are respectively arranged on two opposite sides of the reaction container 1 along the first direction. In this way, the center of gravity of the pretreatment equipment is more stable.

[0097] For some examples, see Figure 1 and Figure 2 The pretreatment equipment includes a frame 7 and a walking mechanism 8. The reaction container 1, the condensing device 2, the drying device 3 and the collecting device 4 are all arranged on the frame 7, and the walking mechanism 8 is arranged at the bottom of the frame 7.

[0098] The walking mechanism 8 is used to drive the frame 7 to walk.

[0099] In this embodiment, the traveling mechanism 8 drives the frame 7 to travel, so as to conveniently adjust the position of the pretreatment equipment according to needs.

[0100] For some examples, see Figure 1 and Figure 2 The walking mechanism 8 can be a roller. Exemplarily, the roller includes but is not limited to a universal wheel or a fixed wheel and the like.

[0101] For some examples, see Figure 1 and Figure 2 There can be four rollers, and the four rollers are arranged symmetrically in a quadrilateral.

[0102] For some examples, see Figures 1 to 4, the condensation device 2 is located above the reaction container 1.

[0103] For example, see Figures 1 to 7 The condensation device 2 includes a spirally extending condenser tube 21, the space inside the condenser tube 21 is a condensation chamber 2a, and the first end of the condenser tube 21 passes through the bottom of the cooling chamber 2d and is connected to the gas outlet 1c. The gaseous substances in the reaction chamber 1a can enter the condenser tube 21 through the first end of the condenser tube 21, and the condensed liquid substances in the condensation chamber 2a can flow back to the reaction chamber 1a through the first end of the condenser tube 21.

[0104] In this embodiment, the condensation device 2 is located above the reaction container 1, and the liquid water and treatment reagents in the condensation chamber 2a after condensation can flow back to the reaction chamber 1a more smoothly under the action of gravity, thereby improving the reflux rate.

[0105] For some examples, see Figures 4 to 7 , the second end of the condenser tube 21 passes through the top of the cooling chamber 2d and is connected to the drying device 3. The spiral extension of the condenser tube 21 means that the condenser tube 21 is roughly in the shape of a spiral line, and the condenser tube 21 is a spirally wound pipeline. The second end of the condenser tube 21 passes through the top of the cooling chamber 2d, and the length of the condenser tube 21 can be increased without significantly increasing the volume of the condensing device 2, thereby extending the contact time between the gaseous substance and the cooling fluid and improving the condensation effect.

[0106] For some examples, see Figure 7 The condensing device 2 includes a housing 22, the space inside the housing 22 is a cooling chamber 2d, the condensing tube 21 is arranged inside the housing 22, and the height of the inlet 2da of the cooling chamber 2d is higher than the height of the outlet 2db of the cooling chamber 2d. Exemplarily, the inlet 2da of the cooling chamber 2d and the outlet 2db of the cooling chamber 2d are located on two opposite sides of the housing 22 in the radial direction. The cooling fluid flows from top to bottom, and the gaseous substance moves from bottom to top in the condensing chamber 2a. The cooling fluid and the gaseous substance move in the wrong direction, which prolongs the cooling time and improves the cooling effect.

[0107] For some examples, see Figures 1 to 4 , the drying device 3 is higher than the collecting device 4.

[0108] Exemplarily, the drying device 3 may be located above one of the collecting devices 4 .

[0109] In this embodiment, the drying device 3 is higher than the collecting device 4 , and a switch valve may not be provided between the drying device 3 and the collecting device 4 , and the absorption liquid in the collecting device 4 will not enter the drying device 3 .

[0110] For some examples, see Figure 3 and Figure 4The pretreatment equipment includes a bending pipe 10, which connects the condensation outlet 2c and the inlet 3a of the drying device 3. The bending pipe 10 includes a planar bending section 101, which bends and extends along a horizontal plane to form a planar winding structure.

[0111] A planar winding structure refers to a structure that extends in a winding manner along a horizontal plane.

[0112] Exemplarily, the bending tube 10 includes two first tube segments 102, the first tube segments 102 extend in the vertical direction, and the plane bending segment 101 includes a plurality of second tube segments 1011 connected in sequence, the second tube segments 1011 extend in a straight line in the horizontal plane, and two adjacent second tube segments 1011 intersect. The two first tube segments 102 are respectively connected to the second tube segments 1011 at the head end and the tail end; one of the first tube segments 102 is connected to the condensation outlet 2c, and the other first tube segment 102 is connected to the inlet 3a of the drying device 3.

[0113] Exemplarily, the planar zigzag section 101 includes two second pipe sections 1011 connected in sequence, the two second pipe sections 1011 intersect with each other, and the two first pipe sections 102 are respectively connected to the two second pipe sections 1011 .

[0114] It is understandable that the number of the second pipe segments 1011 may also be at least three, for example, 3, 4 or more, so that at least three second pipe segments 1011 are connected in sequence to form a pipeline that bends and extends in a horizontal plane.

[0115] In this embodiment, the planar tortuous section 101 can extend the length of the bent tube 10 without significantly increasing the size of the bent tube 10 in the up-down direction, thereby extending the path of the gaseous substance from the condensation chamber 2a, which is beneficial to further reduce the temperature of the gaseous substance and further promote the condensation of water vapor, etc., so that the drying device 3 can absorb water vapor, and can also reduce the risk of water vapor reflux to the condensation chamber 2a.

[0116] For some examples, see Figure 3 and Figure 4 The drying device 3 has a drying chamber, an inlet 3a and an outlet 3b. Both the inlet 3a and the outlet 3b are connected to the drying chamber. The inlet 3a is formed at the top of the drying device 3, and the outlet 3b is formed at the bottom of the drying device 3.

[0117] Specifically, the drying chamber may be filled with a desiccant, which can absorb water. The desiccant can absorb water vapor chemically or physically, which is not limited in the present application.

[0118] In this embodiment, the inlet 3a is formed at the top of the drying device 3, and the outlet 3b is formed at the bottom of the drying device 3. The gaseous substance enters the drying device 3 from the top and then exits the drying device 3 from the outlet 3b at the bottom, which can effectively prolong the contact time between the gaseous substance and the desiccant and improve the drying effect.

[0119] For some examples, see Figure 1 and Figure 2 The pretreatment device includes a controller and a temperature detection element 20. The temperature detection element 20 is arranged in the reaction container 1 to detect the temperature in the reaction chamber 1a. The controller controls the start and stop of the temperature bath circulation device 6 according to the temperature detected by the temperature detection element 20.

[0120] In this embodiment, the controller controls the start and stop of the temperature bath circulation device 6 according to the temperature detected by the temperature detection element 20. The temperature detection element 20 can be used to provide temperature feedback to the reaction container 1 to heat the reaction container 1 at a constant temperature, thereby maintaining the temperature in the reaction chamber 1a to meet the reaction temperature.

[0121] For some examples, see Figure 1 and Figure 2 The pretreatment equipment includes a pressure detection component 30, which is arranged in the reaction container 1 to detect the pressure in the reaction chamber 1a.

[0122] In this embodiment, the pressure detection element 30 can detect the pressure in the reaction chamber 1a, and the progress of the reaction can be monitored according to the pressure in the reaction chamber 1a.

[0123] For some examples, see Figures 1 to 4 There can be multiple collecting devices 4, and multiple collecting devices 4 can be connected in series. Specifically, the air supply port of the first collecting device 4 is connected to the exhaust port 3b of the drying device 3, and the air supply port of the next collecting device 4 is connected to the exhaust port of the previous collecting device 4. In this way, the series connection of multiple collecting devices 4 is completed.

[0124] For example, two, three, four or more collecting devices 4 may be connected in series.

[0125] In this embodiment, a plurality of collection devices 4 connected in series can collect carbon dioxide, thereby improving the collection rate of carbon dioxide.

[0126] For some examples, see Figures 1 to 4 The frame 7 includes a frame 71 and a partition 72, the partition 72 is arranged in the frame 71, the collecting device 4 includes a cover 41 and a bottle 42 having a collecting cavity, the bottle 42 has a collecting cavity and a take-in and take-out port communicating with the collecting cavity, the cover 41 is detachably connected to the bottle 42 to close the take-in and take-out port. The cover 41 is fixed to the partition 72.

[0127] Exemplarily, the cover body 41 and the bottle body 42 may be connected in a detachable manner by snap connection, threaded connection, screw connection or bolt connection.

[0128] In this embodiment, the cover body 41 and the bottle body 42 are detachably connected, and the cover body 41 is fixed on the partition 72. When it is necessary to add absorption liquid to the bottle body 42 or to take out the carbon-containing precipitate in the bottle, the bottle body 42 can be removed from the cover body 41, and the absorption liquid can be injected into the collection chamber or the carbon-containing precipitate can be taken out through the access port without disassembling the entire collection device 4, which is simple to operate.

[0129] For some examples, see Figure 1 and Figure 2 , the condensing device 2 and the liquid pump 9 can be fixed to the partition 72.

[0130] For some examples, see Figure 1 and Figure 2 The liquid pump 9 can be located above the partition 72 , the condensing device 2 can be installed through the partition 72 , and the reaction container 1 , the warm bath circulation device 6 and the cold bath circulation device 5 can all be located below the partition 72 .

[0131] In this embodiment, the partition 72 can provide support for the liquid pump 9 and the condensation device 2. The reaction vessel 1, the warm bath circulation device 6 and the cold bath circulation device 5 can all be located below the partition 72. The above-mentioned structural components can be placed in upper and lower partitions to facilitate pipeline layout.

[0132] The following is a specific example to further illustrate the pretreatment device provided in the embodiment of the present application. Figures 1 to 7The pretreatment equipment includes a reaction vessel 1, a condensation device 2, a drying device 3, a collection device 4, a cold bath circulation device 5 and a warm bath circulation device 6. The reaction vessel 1 includes a reaction chamber 1a, a liquid outlet 1b and a gas outlet 1c, and the liquid outlet 1b and the gas outlet 1c are both connected to the reaction chamber 1a; the condensation device 2 includes a condensation chamber 2a, a condensation inlet 2b, a condensation outlet 2c and a cooling chamber 2d, and the condensation inlet 2b and the condensation outlet 2c are both connected to the condensation chamber 2a, and the condensation inlet 2b is connected to the gas outlet 1c. The cooling chamber 2d is used to circulate cooling fluid, and the cooling chamber 2d is isolated from the condensation chamber 2a, and the condensation chamber 2a is located in the cooling chamber 2d; the drying device 3 is connected to the condensation outlet 2c, and the drying device 3 is used to absorb water vapor; the collection device 4 is connected to the drying device 3, and the collection device 4 contains an absorption liquid, and the absorption liquid is used to absorb carbon dioxide from the reaction chamber 1a. The volume of the reaction chamber 1a is 100L. The reaction container 1 includes a liquid inlet 1d connected to the reaction chamber 1a, and the liquid inlet 1d is used to introduce environmental water samples and treatment reagents into the reaction chamber 1a. The reaction container 1 includes an air inlet 1e connected to the reaction chamber 1a, and the air inlet 1e is used to introduce carrier gas into the reaction chamber 1a. The cold bath circulation device 5 is used to introduce a circulating cooling fluid into the cooling chamber 2d, and the warm bath circulation device 6 is used to introduce a circulating heating fluid into the heating chamber 1f.

[0133] The treatment reagents include persulfate oxidant and acid, and the acid includes phosphoric acid or sulfuric acid.

[0134] The absorption liquid includes calcium chloride and ammonium chloride, and the ammonium chloride is used to adjust the pH value of the absorption liquid. For example, the pH value of the absorption liquid can be between 10 and 11. Specifically, calcium chloride and carbon dioxide react under alkaline conditions to generate calcium carbonate precipitation.

[0135] The pretreatment equipment pretreats inorganic carbon and organic carbon into calcium carbonate precipitate by wet oxidation method. The calcium carbonate precipitate can be added to scintillation liquid for liquid scintillation measurement to measure and analyze the activity concentration of C-14.

[0136] The following steps can be used to pre-treat environmental water samples:

[0137] S10, the air tightness of the pretreatment equipment may be checked by passing a carrier gas such as nitrogen through the pretreatment equipment;

[0138] S20, cleaning the interior of the pretreatment equipment with deionized water, and closing the liquid outlet 1b after the cleaning liquid is drained;

[0139] S30, introducing a carrier gas such as nitrogen into the reaction container 1 again to exhaust the gas in the reaction container 1;

[0140] S40, adding an absorption liquid such as an inorganic base or an organic base to the absorption device;

[0141] S50, the environmental water sample, phosphoric acid and persulfate oxidant are added into the reaction chamber 1a through the liquid pump 9, the reaction chamber 1a is heated through the warm bath circulation device 6, and the temperature in the reaction chamber 1a is controlled at 95±3°C.

[0142] Steps S10 , S20 , S30 , S40 and S50 may be performed sequentially.

[0143] In the reaction chamber 1a, organic carbon and inorganic carbon react with the persulfate oxidant, and the generated gaseous substance containing carbon dioxide gas passes through the condensing device 2 and the drying device 3, and is absorbed by the absorption device. The absorption liquid in the absorption device is adjusted to a pH of 10-11 by ammonium chloride, and calcium chloride reacts with carbon dioxide to form calcium carbonate precipitation.

[0144] An appropriate amount of calcium carbonate precipitate can be taken from the absorption device and dried, and the dried calcium carbonate powder can be added to scintillation liquid for liquid scintillation measurement.

[0145] In this embodiment, the organic carbon and inorganic carbon in the environmental water sample are converted into calcium carbonate precipitate by wet oxidation method to complete the pretreatment of the environmental water sample. The calcium carbonate precipitate can react with the scintillation liquid to perform liquid scintillation measurement to achieve the measurement and analysis of C-14. The gaseous substances discharged from the gas outlet 1c are condensed by the condensation device 2 to reduce the water content of the gaseous substances. The liquid water and treatment reagents after condensation can be refluxed to the reaction chamber 1a through the condensation inlet 2b, so as to achieve the purpose of recycling the treatment reagents and reducing the waste of resources. The drying device 3 can further absorb water vapor, further reduce the water content of the gaseous substances, and improve the reaction efficiency of the absorption liquid. The reaction container 1 can hold a large volume of environmental water samples to meet the measurement of C-14 activity concentration in environmental water bodies, especially in environmental water bodies around nuclear power plants.

[0146] In the description of this specification, the description with reference to the terms "an embodiment", "some embodiments" and "exemplary" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0147] The various embodiments / implementations provided in this application can be combined with each other without causing any contradiction. The above description is only a preferred embodiment of this application and is not intended to limit this application. For those skilled in the art, this application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included in the protection scope of this application.

Claims

1. A pretreatment device for measuring and analyzing C-14 in environmental water samples, characterized in that: include: A reaction container, comprising a reaction chamber, a liquid outlet and a gas outlet, wherein the liquid outlet and the gas outlet are both connected to the reaction chamber; A condensation device, comprising a condensation chamber, a condensation inlet, a condensation outlet and a cooling chamber, wherein the condensation inlet and the condensation outlet are both connected to the condensation chamber, the condensation inlet is connected to the air outlet, the cooling chamber is used to circulate a cooling fluid, the cooling chamber is isolated from the condensation chamber, and the condensation chamber is located in the cooling chamber; A drying device, connected to the condensation outlet, and used to absorb water vapor; A collecting device is communicated with the drying device, wherein the collecting device contains an absorption liquid, and the absorption liquid is used to absorb carbon dioxide from the reaction chamber.

2. The pretreatment equipment according to claim 1, characterized in that: The volume of the reaction chamber is not less than 50L.

3. The pretreatment equipment according to claim 1, characterized in that: The reaction container comprises a liquid inlet communicated with the reaction chamber, and the liquid inlet is used to introduce environmental water samples and treatment reagents into the reaction chamber.

4. The pretreatment equipment according to claim 1, characterized in that: The reaction container comprises a gas inlet communicated with the reaction chamber, and the gas inlet is used to introduce a carrier gas into the reaction chamber.

5. The pretreatment equipment according to claim 1, characterized in that: The pretreatment equipment comprises a cold bath circulation device, the inlet and outlet of the cooling chamber are both connected to the cold bath circulation device, and the cold bath circulation device is used to introduce circulating cooling fluid into the cooling chamber.

6. The pretreatment equipment according to claim 5, characterized in that: The cold bath circulation device is arranged on one side of the reaction container along a first direction, and the first direction is perpendicular to the up-down direction.

7. The pretreatment equipment according to claim 1, characterized in that: The pretreatment equipment includes a warm bath circulation device, the reaction container includes a heating chamber, the reaction chamber is located in the heating chamber, and the heating chamber and the reaction chamber are isolated, the inlet and outlet of the heating chamber are both connected to the warm bath circulation device, and the warm bath circulation device is used to introduce a circulating heating fluid into the heating chamber.

8. The pretreatment equipment according to claim 7, characterized in that: The warm bath circulation device is arranged on one side of the reaction container along a first direction, and the first direction is perpendicular to the up-down direction.

9. The pretreatment equipment according to claim 1, characterized in that: The pretreatment equipment comprises a frame and a walking mechanism, the reaction container, the condensing device, the drying device and the collecting device are all arranged on the frame, and the walking mechanism is arranged at the bottom of the frame.

10. The pretreatment equipment according to claim 1, characterized in that: The condensing device is located above the reaction container; and / or the drying device is higher than the collecting device.

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