Method and device for extracting and collecting free water tritium in a biological sample tissue

Abstract

The application discloses a biological sample tissue free water tritium extraction and collection method and device. The method simultaneously applies heating and suction to the biological sample through a vacuum drying box to obtain TFWT steam. The TFWT steam is converted into liquid tritium water after low-temperature cooling and is collected. The sample amount required for TFWT detection and analysis can be quickly and efficiently obtained. The operation is simple. No chemical reagent is introduced into the biological sample in the whole extraction process. On the one hand, the health and safety of the test personnel are protected. On the other hand, the test cost is saved. The corresponding device sequentially connects a vacuum drying box, a low-temperature cooling component, a suction filtration connector and a vacuum pump. The TFWT steam extracted by the vacuum drying box is condensed into liquid tritium water by the low-temperature cooling component, flows out through the suction filtration connector and is collected by a tritium water collection box connected to the bottom end of the suction filtration connector. The device is convenient, safe and efficient.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of radiation environment monitoring and investigation, and particularly relates to a method and device for extracting and collecting tissue free water tritium of a biological sample. BACKGROUND

[0002] Tritium is a natural radioisotope widely existing in the environment and is also an important artificial radioisotope in the nuclear industry. It participates in global hydrogen circulation and all biological metabolic processes and produces radiation exposure to organisms. Tritium in the environment mainly exists in the form of gaseous tritium, tritium water or organic tritium in the atmosphere, water bodies and organisms, among which it mainly exists in the form of tissue free water tritium (TFWT) and organic bound tritium (OBT) in organisms. The current relevant specifications such as the Technical Specifications for Radiation Environment Monitoring (HJ 61-2021), the Technical Specifications for Radiation Background Investigation before Operation of Nuclear Power Plants (HJ 969-2018) clearly stipulate that the detection and analysis of tissue free water tritium (TFWT) and organic bound tritium (OBT) in organisms need to be carried out in the processes of radiation environment quality monitoring, radiation background investigation monitoring before operation of nuclear power plants, and radiation environment monitoring during operation of nuclear power plants. The relevant detection and analysis methods refer to the Analysis Method for Tritium in Water (HJ 1126-2020), which only provides how to detect and analyze the tritium content in water samples containing tritium or liquid effluents, but does not clearly stipulate how to extract and collect tissue free water tritium (TFWT) in organisms and convert it into tritium water that can be detected by the Analysis Method for Tritium in Water (HJ 1126-2020).

[0003] At present, the methods of freezing dehydration, vacuum freeze drying and azeotropic distillation are commonly used to separate TFWT in organisms at home and abroad. The first two methods need a professional freeze dryer to work continuously for 2-3 days to obtain a high TFWT recovery rate (more than 90%), and the biological sample needs to be frozen and decomposed before the instrument is operated to meet the requirements of sample packaging and freeze drying. The azeotropic distillation method is to first crush the biological sample, then put the crushed biological sample into an organic solvent, and then separate the TFWT in the biological sample by heating and distilling the organic solvent, and finally separate the TFWT by fractional distillation. The azeotropic distillation method generally selects an organic solvent with a relatively low azeotropic point and a high water content, such as benzene, toluene, xylene and cyclohexane. This method can extract and separate the TFWT in the biological sample within a few hours, but the recovery rate is relatively low (usually less than 70%). Since the organic solvent is volatile and chemically toxic, it will inevitably have a certain harmful effect on the health of the test personnel. In addition, this method will produce a certain amount of organic waste liquid, and the separated tritium water may contain a small amount of organic solution, which will affect the analysis and determination results of the sample.

[0004] Therefore, it is urgent to develop a method and a device for extracting and collecting free water tritium of biological samples quickly, efficiently, conveniently and safely. SUMMARY

[0005] The application aims to provide a method and a device for extracting and collecting free water tritium of biological samples quickly, efficiently, conveniently and safely.

[0006] To achieve the above object, the application adopts the following technical solutions.

[0007] A method for extracting and collecting free water tritium of biological samples, comprising the following steps:

[0008] S10, placing the biological sample in a vacuum drying oven to generate tissue free water tritium steam through heating and suction of the vacuum drying oven;

[0009] S20, the tissue free water tritium steam is converted into liquid tritium water through low-temperature cooling;

[0010] S30, collecting the liquid tritium water.

[0011] Further, in the step S10, the biological sample is a washed fresh sample, which does not need to be pre-processed by one or more of the following methods: being divided and broken into fine pieces or particles, being frozen at low temperature, and being vacuum freeze-dried.

[0012] Further, in the step S20, the tissue free water tritium steam is condensed into liquid tritium water through a condenser, which is a serpentine condenser, a straight condenser or a spherical condenser.

[0013] Further, between the step S20 and the step S30, the following step is further included:

[0014] S21, filtering the liquid tritium water condensed in the step S20.

[0015] The application further discloses a device for extracting and collecting free water tritium of biological samples, which can realize the above method. The device comprises a vacuum drying oven, a low-temperature cooling assembly, a suction filter connector and a vacuum pump connected in sequence. The suction filter connector is hollow to form a cavity. The suction filter connector is provided with a water inlet, a water outlet and an air outlet, which are all in communication with the cavity. The water inlet is connected with the low-temperature cooling assembly. The water outlet is connected with a tritium water collector. The air outlet is connected with the vacuum pump.

[0016] Further, the vacuum drying oven is provided with a vacuum valve and a gas release valve. The low-temperature cooling assembly comprises a condenser, which has an inlet and an outlet. The inlet is connected with the vacuum valve.

[0017] Further, the filter connector is a water vapor filter, and the cavity further accommodates a filter element.

[0018] Further, a dryer is further included, one end of the dryer is connected to the exhaust port, and the other end is connected to the vacuum pump.

[0019] Further, the low-temperature cooling assembly further includes a low-temperature cooling liquid circulating pump, the low-temperature cooling liquid circulating pump is provided with a cooling liquid inlet and a cooling liquid outlet, the condenser pipe includes an inner pipe and an outer pipe, the inner pipe is sleeved in the outer pipe, the outer pipe is provided with a liquid inlet and a liquid outlet, the liquid inlet is communicated with the cooling liquid outlet, and the liquid outlet is communicated with the cooling liquid inlet.

[0020] Further, the condenser pipe is a serpentine condenser pipe, the serpentine condenser pipe is arranged in an inclined manner, and the use temperature of the low-temperature cooling liquid circulating pump is set to 2-6 DEG C.

[0021] Compared with the prior art, the present application has at least the following beneficial effects:

[0022] 1、The biological sample free water tritium extraction and collection method provided by the present application simultaneously applies heating and suction to the biological sample through the vacuum drying box to obtain TFWT vapor, and the TFWT vapor is converted into liquid tritium water after low-temperature cooling and is collected, so that the sample amount required for TFWT detection and analysis can be quickly and efficiently obtained, the operation is simple, and no chemical reagent is introduced into the biological sample in the whole extraction process, which is beneficial to protecting the health and safety of the test personnel and saving the test cost;

[0023] 2、The biological sample tissue free water tritium extraction and collection device provided by the present application sequentially connects a vacuum drying box, a low-temperature cooling assembly, a filter connector and a vacuum pump, directly heats and suctions the biological sample by using the vacuum drying box to provide a constant-temperature heating and negative pressure environment, accelerates the evaporation of TFWF in the biological sample, and TFWT vapor is condensed into liquid tritium water by the low-temperature cooling assembly, flows out from the filter connector, and is collected by a tritium water collection box connected to the bottom end of the filter connector, so that the tissue free water tritium in the biological sample is quickly and efficiently extracted, and the use is more convenient and safe.

[0024] 3、The biological sample tissue free water tritium extraction and collection device provided by the application has high containment of the vacuum drying box to biological samples, only needs to place the washed biological samples in the tray in the sample chamber of the vacuum drying box, does not need to divide and break the biological samples into fine pieces or granules, and can select a vacuum drying box with a suitable volume according to the actual sample situation, or select a vacuum drying box with a larger volume to meet the extraction requirements of TFWT in different types of biological samples at one time, that is, only one test is needed to extract sufficient biological TFWT water tritium for subsequent test analysis, is convenient and efficient to use, saves the sample processing time, and is good in practicality;

[0025] 4、In the application, the cooling assembly includes a condensing pipe and a low-temperature cooling liquid circulating pump, the low-temperature cooling liquid circulating pump is used for circulating and conveying the cooling liquid to the outer pipe of the condensing pipe to condense the tritium-containing steam in the inner pipe, the low-temperature cooling liquid circulating pump is convenient to control the actual cooling temperature, can ensure effective condensation of TFWT steam and will not freeze into ice to affect the flowability of the pipeline, and further improves the safety of the device in use;

[0026] 5、In the application, the suction filter connector can also be preferably a water vapor filter, that is, a filter element is also accommodated in the inner cavity of the suction filter connector, the water vapor filter can not only filter the tritium water flowing out of the condensing pipe, but also has the functions of liquefying water vapor and fog, and discharges the filtered air, can further improve the collection efficiency of TFWT, can connect a desiccator to the side wall interface thereof, reduces the replacement frequency of the desiccator and protects the vacuum pump from water vapor corrosion;

[0027] 6、In the biological sample tissue free water tritium extraction and collection device provided by the application, the side wall interface of the suction filter connector can be further connected with a desiccator, so that the air discharged from the suction filter connector is further dried to reduce the corrosion to the vacuum pump. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The technical roadmap of the biological sample tissue free water tritium extraction and collection method provided by the application is provided.

[0029] Figure 2 The schematic diagram of the biological sample tissue free water tritium extraction and collection device provided by the embodiment of the application is provided.

[0030] Figure 2 10, vacuum drying box, 101, vacuum valve, 102, air release valve;

[0031] 201, condensing pipe, 2011, inner pipe, 202, low-temperature cooling liquid circulating pump;

[0032] 30, suction filter connector, 301, water inlet, 302, water outlet, 303, air outlet;

[0033] 40, tritium water collector;

[0034] 50, vacuum pump;

[0035] 60, connecting pipe;

[0036] 70, dryer, 701, drying agent. DETAILED DESCRIPTION

[0037] The prior art has the technical problem that the pre-treatment of biological samples is complex, the device for extracting and collecting tritium in free water of biological sample tissues is not convenient, safe and efficient enough, and needs to be further improved.

[0038] Therefore, the present application proposes a new scheme, and the present application will be described in detail below in combination with the drawings and specific embodiments.

[0039] The present application provides a method for extracting and collecting tritium in free water of biological sample tissues, as shown in the accompanying drawings, which comprises the following steps: Figure 1

[0040] S10, placing the biological sample in a vacuum drying oven, and generating tissue free water tritium steam by heating and suction of the vacuum drying oven;

[0041] Specifically, in step S10, the biological sample can be a washed fresh sample, and does not need to be pre-treated by one or more of the following methods: being divided and broken into fine flaky or granular, low-temperature freezing, vacuum freeze-drying, etc. This is mainly because the present application first uses a vacuum drying oven to heat and suction the biological sample at the same time. It does not need to pre-freeze the biological sample or vacuum freeze-drying, etc., and it will not be greatly limited by the storage in the container as in the analytical tube or glass bottle used in the prior art. Through the cooperation of the subsequent steps, it is proved that the fresh sample of the biological sample directly treated by the present application can fully meet the rapid and efficient extraction and collection of tritium in free water of biological sample tissues.

[0042] In step S10, for a biological sample with a larger volume, such as a branch or a leaf with a long biological sample, it can also be roughly divided into several segments, for example, when extracting tritium in free water of lettuce sample tissues, the washed lettuce leaves can be roughly divided into small segments of 3-10 cm, so as to be placed in the sample chamber in the vacuum drying oven.

[0043] In step S10, the heating temperature of the vacuum drying oven for the biological sample is 100-120℃, preferably 105℃, with an error range of ±1℃. If the suction temperature is higher than 120℃, some organic substances may be sucked out, affecting the accuracy of TFWT.

[0044] S20, the tissue free water tritium steam is converted into liquid tritium water by low-temperature cooling; ​

[0045] Specifically, in step S20, the tissue-free tritium vapor can be cryogenically cooled using a conventional cold trap (e.g., the technical solution disclosed in CN 210442151 U). However, using liquid nitrogen as a cold trap is not only expensive but also carries the risk of the vapor freezing into icicles, blocking the airway tube and potentially causing the tube or connecting device to be washed away by high pressure. Therefore, the present invention utilizes a condenser for condensation. The condenser can be a serpentine, straight, or spherical condenser, and is coupled with a low-temperature coolant circulation pump. This circulation pump facilitates control of the actual cooling temperature, ensuring effective condensation of the TFWT vapor while preventing freezing and affecting pipeline fluidity. During operation, the low-temperature coolant circulation pump temperature can be set to 2-6°C, for example, 2°C, 4°C, or 6°C, ensuring effective condensation of the TFWT vapor without freezing and affecting pipeline fluidity.

[0046] S30, collecting the liquid tritium water.

[0047] Specifically, before collecting the liquid tritium water condensed in step S20, it may be further filtered to further improve the collection efficiency of water vapor.

[0048] The present invention also provides a device for extracting and collecting tritium from free water in biological sample tissues, which can implement the above-mentioned method for extracting and collecting tritium from free water in biological sample tissues. Figure 2 As shown, the extraction and collection device includes a vacuum drying oven 10, a low-temperature cooling component, a filtration connector 30 and a vacuum pump 50 connected in sequence. The filtration connector 30 is hollow to form a cavity. The filtration connector 30 is provided with a water inlet 301, a drain port 302 and an exhaust port 303. The water inlet 301, the drain port 302 and the exhaust port 303 are all connected to the cavity. The water inlet 301 is connected to the low-temperature cooling component, the drain port 302 is connected to a tritium water collector 40, and the exhaust port 303 is connected to the vacuum pump 50.

[0049] In a specific embodiment, the vacuum drying oven 10 is provided with a vacuum valve 101 and a gas release valve 102, the low-temperature cooling assembly includes a condenser tube 201 having an inlet and an outlet, the inlet is connected with the vacuum valve 101; the suction filter connector 30 includes a connector body, the connector body is hollow to form the cavity (not marked in the figure), the top end, the bottom end and the side wall of the connector body are provided with interfaces, the interface at the top end is the water inlet 301, the interface at the bottom end is the water outlet 302, and the interface at the side wall is the gas outlet 303, the water inlet 301 is connected with the outlet of the condenser tube 201 and used for receiving the tritium water condensed in the condenser tube 201, the tritium water flows into the cavity through the water inlet 301 and then flows out of the water outlet 302. The tritium water collector 40 is connected with the water outlet 302 of the suction filter connector 30 and used for collecting the tritium water obtained after condensation, the collector can be a common container made of glass or quartz; the vacuum pump 50 is connected with the interface (i.e. the gas outlet 303) of the side wall of the connector body, so that the vacuum pump 50 is sequentially connected with the suction filter connector 30, the condenser tube 201 and the vacuum drying oven 10 to perform vacuumizing treatment on the vacuum drying oven 10, the condenser tube 201 and the suction filter connector 30.

[0050] Referring to Figure 1 As shown in the figure, the technical principle adopted by the present application is to simultaneously act on the biological sample by heating and suction to accelerate the evaporation of TFWT in the biological sample to obtain TFWT vapor, and the TFWT vapor is converted into liquid tritium water after low-temperature cooling and is collected. The present application adopts the design concept of the vacuum drying oven according to the mass and density differences of different types of biological samples, increases the sample capacity, and at the same time provides a constant temperature heating and negative pressure working environment for the biological sample through the vacuum drying oven, so as to improve the evaporation rate of TFWT in the biological sample, promote the rapid drying of the biological sample, and at the same time avoid the entry of external gas into the drying oven to affect the composition and content of the tritium water.

[0051] In the present application, the vacuum drying oven 10 can be selected from commercially available products, which is a traditional and mature drying device commonly used in pharmaceutical, chemical, food and other industries for low-temperature drying of medicine powder, pills, tablets and heat-sensitive materials. Currently, there is no related report on its application in the field of extraction and collection of tissue free water tritium in biological samples. The commercially available vacuum drying oven 10 generally has a box body, a plurality of sample chambers for placing samples are arranged in the box body, the sample chambers can also be separated by a plurality of partitions, the box body is also provided with a vacuum valve 101 and a gas release valve 102, both of which are in communication with the sample chambers, so that the sample chambers can be vacuumized through the vacuum valve 101, and the sample chambers after vacuumization can be re-pressurized through the gas release valve 102. The surface of the box body is also provided with a vacuum gauge, which can real-time reflect the vacuum degree in the sample chamber. As an example, the vacuum drying oven 10 in the present application can be selected from a constant temperature electric heating vacuum drying oven, such as an intelligent temperature control vacuum drying oven (DZF series) produced by Shanghai Yiheng Scientific Instrument Co., Ltd. More specifically, the specific parameters of the selected vacuum drying oven can be: the working environment temperature of the vacuum drying oven is 5-40℃, the temperature control range in the sample chamber is between room temperature (RT) +10℃-200℃, the temperature fluctuation is 1℃, and the maximum vacuum degree in the sample chamber can reach 133pa.

[0052] The water content in different types of biological samples is generally about 60%-90%, and the amount of tritium water required in the radiation detection process is about 50g. The inventor found in actual test that the amount of biological samples required for TFWT extraction and collection is preferably between 250g-350g. The higher the water content of the biological sample, the less the amount of biological sample required, and vice versa. Based on the difference in the amount of biological samples and the density of biological species, in a preferred embodiment, the inner tank size (mm) of the vacuum drying oven 10 is: 320 (length) x 320 (width) x 300 (height), which can accommodate sufficient biological samples (different biological types meet the capacity requirement) for heating and pumping out TFWT in the biological samples at one time, without the need to carry out multiple tests for extraction, thereby reducing the test cycle time. When using the device provided by the present application to extract and collect tritium in tissue free water of biological samples, the cleaned biological samples only need to be placed on the tray and placed in the sample chamber of the drying oven, thereby further saving human resources and processing time.

[0053] Please continue to refer to Figure 2As shown, in the present application, the low-temperature cooling assembly further comprises a low-temperature cooling liquid circulating pump 202, which is provided with a cooling liquid inlet and a cooling liquid outlet, and the condensing pipe 201 comprises an inner pipe 2011 and an outer pipe (not marked in the figure), the inner pipe 2011 is sleeved in the outer pipe, the outer pipe is provided with a liquid inlet and a liquid outlet (the condensing pipe generally follows the principle of liquid inlet at the lower end and liquid outlet at the upper end), the liquid inlet is in communication with the cooling liquid outlet, and the liquid outlet is in communication with the cooling liquid inlet. The condensing pipe 201 can select a common serpentine condensing pipe or a straight condensing pipe or a spherical condensing pipe on the market.

[0054] In the present application, the main function of the low-temperature cooling assembly is to cool the TFWT steam pumped out of the vacuum drying box into liquid tritium water. In a specific embodiment, the capacity of the cooling liquid in the low-temperature cooling liquid circulating pump 202 can be designed as 4L, the temperature control range is between-10℃ and normal temperature, and the flow rate is 15L / min. The low-temperature antifreeze cooling liquid can be selected from a cooling liquid composed of 30% by volume of ethanol and 70% by volume of deionized water, and the condensation point of the cooling liquid is about-10℃, which is sufficient to meet the functional effect of the cooling liquid circulation cooling. The extraction and collection device in the prior art uses liquid nitrogen as a cold trap, which not only has a high use cost, but also has the risk of water vapor freezing into ice columns to block the gas guide pipe and cause the gas guide pipe or the connecting device to be washed away by high pressure. The present application uses a low-temperature cooling liquid circulating pump as a cooling appliance, which is convenient for controlling the actual cooling temperature, can ensure effective condensation of the TFWT steam, and will not freeze into ice to affect the flowability of the pipeline. During operation, the temperature of the low-temperature cooling liquid circulating pump 202 can be set to 2-6℃, for example, 2℃, 4℃, 6℃, which ensures effective condensation of the TFWT steam and will not freeze into ice to affect the flowability of the pipeline. As an example, the low-temperature cooling liquid circulating pump 202 can select a low-temperature cooling liquid circulating pump with a model of LC-LTC-5 / 10 produced by Hunan Lichen Instrument Technology Co., Ltd.

[0055] In a preferred embodiment, by selecting a serpentine condensing pipe and prolonging the length of the serpentine condensing pipe and its layout mode to cooperate with the low-temperature cooling liquid circulating pump 202, the condensation effect of the TFWT steam into tritium water is further ensured. A serpentine condensing pipe with an effective length of 600mm, a caliber of 24mm and an outer diameter of 40mm is selected, and the condensing pipe 201 is arranged in an inclined manner to prolong the residence time of the condensed tritium water in the condensing pipe, thereby increasing the flow resistance of the TFWT steam and further increasing the condensation effect of the TFWT steam. The included angle between the condensing pipe 201 and the horizontal direction can be about 45°.

[0056] In the present application, the filter connector 30 can be a glass tee, which can be further improved as a water vapor filter, at this time, the inner cavity is provided with a filter element. The tritium water cooled by the condenser tube (the inner tube 2011) contains a small amount of water vapor and air components, and a water vapor filter is connected at the tail end of the condenser tube to further improve the collection efficiency of the TFWT. The water vapor filter not only filters the tritium water flowing out of the condenser tube 201, but also liquefies the water vapor and mist, and discharges the filtered air. The water vapor filter can be inclined or vertically arranged, so that the filtered tritium water can flow into the tritium water collector 40 under the action of gravity.

[0057] In a preferred embodiment, the water vapor filter used adopts a design structure of vertical air inlet and horizontal air outlet, and a drainage interface (i.e. the drainage port 302) is arranged at the bottom. The water vapor filter is arranged vertically, and the filtered TFWT tritium water can directly flow into the tritium water collector 40 from the drainage port 302, and the filtered air is discharged from the air outlet 303. The air outlet 303 can be further designed to be arranged close to the top. As an example, the filter connector can select a CEMS-Filter of GL-2T type produced by Suzhou Jinghuan Filter Technology Co., Ltd., which is about 20 cm long and about 6 cm in diameter. The filter connector shell is made of thick high-quality transparent glass material, which can withstand a temperature of up to 180℃ and has strong corrosion resistance. The supporting filter element has a maximum pore size of 0.1μm, high filtration precision, and can effectively separate water vapor and mist in the gas to ensure the filtering effect of the TFWT.

[0058] In the present application, the vacuum pump 50 is sequentially connected with the filter connector 30, the condenser tube 201 and the vacuum drying box 10 through the connecting pipeline 60 (such as a connecting hose), so as to provide a negative pressure environment inside the pipeline, promote the flow of TFWT vapor, air and moisture, and accelerate the collection rate of TFWT. In an embodiment, the vacuum pump 50 can be a rotary vane vacuum pump, and the specific parameters of the vacuum filter pump can be: size (length x width x height) 300 x 120 x 235 mm, air suction rate 120 L / min, limit pressure about 950 kpa, and vacuum degree in the pipeline can be reduced to 50 mbar, and it can work continuously for 24 hours.

[0059] On the basis of the above structure and design, the present application can further include a dryer 70.

[0060] One end of the dryer 70 is connected with the air outlet 303 of the connector body, and the other end is connected with the vacuum pump 50.

[0061] Reference Figure 2As shown, the dryer 70 can be a straight tube with both ends open, and the desiccant 701 is placed inside the tube. The dryer 70 is preferably vertically arranged, and the air discharged from the suction filter connector 30 (the air outlet 303) is taken in from the bottom of the straight tube and discharged from the top. The main function of the dryer 70 is to further dry the air discharged from the suction filter connector 30 to reduce the water vapor in the air from corroding the vacuum pump 50. In a specific embodiment, the dryer 70 is composed of a straight tube with both ends open, about 20 cm long and about 5 cm in diameter, and the tube wall is made of transparent glass, and the tube is filled with SiO2 desiccant. During use, the desiccant can be replaced by observing the color change of the desiccant inside the tube (the normal color of SiO2 desiccant is blue, and it turns pink when it is wet). The desiccant that has changed color due to moisture can be reused after drying, which is convenient and cost-effective.

[0062] The working process of the extraction and collection device provided by the application can include the following steps:

[0063] (1) Pre-cooling of the low-temperature cooling assembly: open the cooling liquid circulation and refrigeration button in the low-temperature cooling liquid circulation pump 202, and pre-cool for 20 minutes, so that the temperature of the cooling liquid is reduced to about 4°C (acceptable error range is ±2°C);

[0064] (2) Heating the biological sample: clean the biological sample and lay it flat on the tray, and place it in the sample chamber of the vacuum drying box 10. Close the chamber door and the air release valve 102 of the vacuum drying box 10, open the vacuum valve 101 and the heating switch, and set the temperature of the sample chamber of the vacuum drying box to 105°C. The vacuum drying box 10 is vacuumized by the vacuum pump 50, and when the vacuum degree in the vacuum drying box 10 is 85 kPa, the vacuum valve 101 of the vacuum drying box 10 is closed, and then the switch of the vacuum pump 50 is closed. The biological sample in the vacuum drying box 10 starts to be heated, and TFWT water vapor is released;

[0065] (3) Suction filtering TFWT water vapor

[0066] Due to the evaporation of TFWT vapor in the biological sample in the vacuum drying box 10, the vacuum degree in the vacuum drying box 10 will continuously decrease, and when the vacuum degree in the vacuum drying box 10 is reduced to 50 kPa, the vacuum valve 101 of the vacuum drying box 10 and the vacuum pump 50 are opened in turn to start extracting TFWT vapor. The vapor is sucked into the condenser tube 201 through the connecting pipe to be condensed into liquid tritiated water, and then flows into the tritiated water collector 40 through the water inlet 301 of the suction filter connector 30 and the water outlet 302, and is collected as subsequent tritiated water to be detected and analyzed;

[0067] (4) Closing the device

[0068] After collecting enough tritium water, the heating switch of the vacuum drying box 10 is closed, the vacuum pump 50 is used to continue vacuumizing for about 1 hour, then the vacuum valve 101 of the vacuum drying box 10 is closed, the air release valve 102 is opened, then the low-temperature cooling liquid circulating pump 202 and the vacuum pump 50 are closed in turn, finally the tritium water collector is taken out, and the tritium water is poured out.

[0069] The biological sample tissue free water tritium extraction and collection device provided by the application is arranged according to the method shown in the figure, the serpentine condenser is arranged obliquely, the water vapor filter and the dryer are added, and the two are arranged vertically. Figure 2 The TFWT collection and extraction tests of different types of organisms are carried out according to the above method, and the test results show that the samples of the organisms after pretreatment are laid in the tray and placed in the sample chamber of the vacuum drying box, heated and sucked in the device for 2 hours, and after stopping heating, continue to suck for 1 hour, and enough tritium water can be collected (see Table 1 for specific test data), which meets the sample quantity requirement of subsequent detection and analysis, and proves that the extraction efficiency of the device for biological TFWT is significantly higher than that of the currently popular freeze-drying, vacuum freeze-drying and azeotropic distillation, and the condensation and collection efficiency of TFWT is also better than or at the same level as other processing methods.

[0070] Table 1 Test results of TFWT extraction and collection provided by the application

[0071]

[0072] The biological tissue free tritium (TFWT) extraction and collection device provided by the application is safe, convenient and efficient, and the use and promotion of the device can effectively improve the detection and monitoring work efficiency of biological tissue free tritium in radiation environment monitoring.

[0073] The above examples are only used to explain the technical solutions of the application and not to limit them, although the above examples have specifically described the application, related technicians should understand that the specific embodiments of the application can be modified or replaced by the same, without departing from the spirit and scope of the application. Any modification and equivalent replacement should be covered in the scope of the claims of the application.

Claims

1. A method for extracting and collecting tritium from free water in biological sample tissues, characterized by: The following steps are involved: S10, placing the biological sample in a vacuum drying oven, and generating tissue-free water tritium vapor through heating and suction in the vacuum drying oven; in step S10, the biological sample is a fresh, clean sample, and does not require one or more pretreatments of fragmentation into fine flakes or granules, cryogenic freezing, or vacuum freeze-drying; S20, the tritium vapor in the tissue-free water is converted into liquid tritium water through cryogenic cooling; the cryogenic cooling is achieved by a cryogenic cooling assembly, which includes a condenser and a cryogenic coolant circulation pump. The cryogenic coolant circulation pump circulates coolant to the outer tube of the condenser to condense the tritium vapor in the inner tube. The operating temperature of the cryogenic coolant circulation pump is set to 2-6°C; S21, filtering the liquid tritium water condensed in step S20: connecting a water vapor filter to the tail end of the condenser tube, using the water vapor filter to filter the liquid tritium water flowing out of the condenser tube, liquefy uncondensed water vapor and mist, and discharge the filtered air; S30, collecting the liquid tritium water.

2. The method for extracting and collecting tritium from free water in biological sample tissue according to claim 1, characterized in that: In step S20, the condenser is a serpentine condenser, a straight condenser, or a spherical condenser.

3. A device for extracting and collecting tritium from free water in biological sample tissue, used to implement the method for extracting and collecting tritium from free water in biological sample tissue according to claim 1 or 2, characterized in that: It includes a vacuum drying oven, a low-temperature cooling component, a suction filter connector and a vacuum pump connected in sequence. The suction filter connector is hollow to form a cavity. The suction filter connector is provided with a water inlet, a drain outlet and an exhaust outlet. The water inlet, the drain outlet and the exhaust outlet are all connected to the cavity. The water inlet is connected to the low-temperature cooling component, the drain outlet is connected to a tritium water collector, and the exhaust outlet is connected to the vacuum pump; the low-temperature cooling component includes a condenser and a low-temperature coolant circulation pump, and the low-temperature coolant circulation pump circulates the coolant to the outer tube of the condenser to condense the tritium-containing vapor in the inner tube. The operating temperature of the low-temperature coolant circulation pump is set to 2~6°C; the suction filter connector is a water vapor filter, and a filter element is also accommodated in the cavity.

4. The device for extracting and collecting tritium from free water in biological sample tissue according to claim 3, characterized in that: The vacuum drying box is provided with a vacuum valve and an air release valve; the condenser has an inlet and an outlet, and the inlet is connected to the vacuum valve.

5. The device for extracting and collecting tritium from free water in biological sample tissue according to claim 3, characterized in that: It also includes a dryer, one end of which is connected to the exhaust port, and the other end of which is connected to the vacuum pump.

6. The device for extracting and collecting tritium from free water in biological sample tissue according to claim 3, characterized in that: The low-temperature coolant circulation pump is provided with a coolant inlet and a coolant outlet, the condenser includes an inner tube and an outer tube, the inner tube is sleeved in the outer tube, the outer tube is provided with a liquid inlet and a liquid outlet, the liquid inlet is connected to the coolant outlet, and the liquid outlet is connected to the coolant inlet.

7. The device for extracting and collecting tritium from free water in biological sample tissue according to claim 6, characterized in that: The condenser is a serpentine condenser, and the serpentine condenser is arranged obliquely.

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