CN113866396B - Method for analyzing transuranics in feces sample - Google Patents

Abstract

The invention relates to a method for analyzing transuranic nuclides in feces samples, which belongs to the technical field of nuclear monitoring. The method includes the following steps: S1. Using an automatic feces sample sampling device to automatically collect feces samples from the sampled person, and automatically collect the feces samples In the sample tank; S2, put the feces sample into the carbonization and ashing integrated equipment for carbonization and ashing treatment to obtain the ash sample; S3, perform digestion treatment and acidity modulation on the ash sample to obtain the feed liquid; S4. Using an automatic separation and purification device to separate and purify the feed liquid to obtain a sample; S5. Selecting different equipment to measure the sample according to the measurement requirements of different nuclides. The method provided by the invention is based on a semi-automatic device to complete the analysis of transuranic nuclides in fecal samples. The operation process is simple and convenient, the analysis process is standardized, the analysis precision, accuracy and efficiency are improved, and technical support is provided for personnel internal exposure monitoring and dose evaluation.

Description

A method for analyzing transuranic nuclides in feces samples

technical field

The invention belongs to the technical field of nuclear monitoring, in particular to a method for analyzing transuranic nuclides in feces samples.

Background technique

Nuclear fuel reprocessing plants mainly operate on transuranium nuclides, especially in complex processes and high-temperature and high-humidity environments where radioactive particles such as aerosols are easily produced, which inevitably causes internal exposure hazards to personnel. Internal exposure monitoring of uranium and transuranium nuclides is one of the important issues for personnel protection in reprocessing plants. However, the current internal radiation monitoring methods, such as biological samples, urine samples and direct lung measurement techniques, have the problem that the detection limit is too high, and the excretion fraction of transuranic nuclides in the feces of biological samples is several orders of magnitude higher than that in urine , so the measurement of transuranic nuclides in feces can obtain a lower detection limit, which can lower the detection limit of the routine monitoring process, and will have certain advantages in the monitoring of internal exposure of personnel.

Contents of the invention

In order to solve the defects in the prior art, the purpose of the present invention is to provide a method for analyzing transuranic nuclides in feces samples for the internal irradiation monitoring requirements of personnel in reprocessing plants. The operation process is simple and convenient, and the analysis process is standardized, which improves the analysis precision, accuracy and efficiency, and provides technical support for personnel internal exposure monitoring and dose evaluation.

For achieving above object, a kind of technical scheme that the present invention adopts is:

A method for analyzing transuranic nuclides in feces samples, comprising the following steps:

S1. Use the automatic fecal sample sampling device to perform automatic fecal sample sampling on the sampled person, and automatically collect the fecal sample in the sample tank;

S2. Put the feces sample into the integrated carbonization and ashing equipment for carbonization and ashing to obtain the ash sample;

S3, subjecting the ash sample to digestion treatment and acidity modulation to obtain a feed liquid;

S4. Using an automatic separation and purification device to separate and purify the acidity-modulated feed liquid to obtain a sample;

S5. Selecting different equipment to measure the sample according to the measurement requirements of different nuclides.

Further, in the method for analyzing transuranic nuclides in fecal samples as described above, the specific steps in step S1 include:

S101. Before sampling, clean, dry, number and weigh each of the sample jars and lids, and record the weight of each of the sample jars and lids, and record the weight of each of the sample jars as m ₀ ;

S102. Put the weighed sample tank into the tank area of the automatic fecal sample sampling device, and put the weighed sample tank lid into the cover area;

S103. The subject presses the switch of the automatic fecal sample sampling device, and when the sample tank is automatically transferred to the designated position under the toilet, the subject sits down and aligns the anus with the mouth of the tank to start sampling; The sample jar is automatically slid away and sealed with a cap, and then automatically moved to the designated position on the left rear side of the device.

Further, in the method for analyzing transuranic nuclides in fecal samples as described above, the carbonization and ashing integrated equipment described in step S2 includes an ashing furnace and a biocharization and ashing tail gas treatment system, and the tail gas port of the ashing furnace is connected to the The tail gas inlet of the biocharization and ashing tail gas treatment system; the carbonization and ashing of fecal samples are realized through the microwave heating of the ashing furnace, and the purification of the tail gas in the carbonization and ashing process is realized through the biocharization and ashing tail gas treatment system deal with.

Further, in the method for analyzing transuranic nuclides in fecal samples as described above, the specific steps of carbonization and ashing in step S2 include:

S201. Weigh the total weight _m1 of the sample tank and the feces in it, then remove the cover of the sample tank, put the sample tank into a quartz crucible, and then put the quartz crucible into an ashing furnace middle;

S202. Setting various heating parameters of the ashing furnace;

S203, sequentially start the automatic ashing program of the ashing furnace and the biochar ashing tail gas treatment system, and simultaneously open the cooling water circulation system to start carbonization and ashing treatment;

S204. The tail gas generated during the carbonization and ashing processes is used to remove tar and malodorous gases in the tail gas through the biocharization and ashing tail gas treatment system, and the purified tail gas is discharged into the air through the tail gas outlet;

S205. After the automatic ashing program ends, keep the ashing furnace running for a preset time, then turn off the power supplies of the ashing furnace and the biochar ashing tail gas treatment system in turn, and keep the ashing furnace door closed, Cool down to room temperature naturally; open the door of the ashing furnace, take out the sample jar, weigh the total weight m ₂ of the sample jar and the sample ash again, and finally calculate the weight m of the sample ash.

Still further, in the method for analyzing transuranic nuclides in feces as described above, the heating parameters in step S202 are set at a carbonization temperature of 300°C, and the carbonization is completed after 10 hours of operation, and the ashing temperature is 450°C, and the ashing is completed after 12 hours of operation.

Still further, in the method for analyzing transuranic nuclides in feces as described above, the formula for calculating the weight of the sample ash in step S205 is: m=m ₂ −m ₀ .

Still further, the method for analyzing transuranic nuclides in feces samples as described above further includes after step S205: transferring the feces sample ash to a glass bottle with a cover for sealed storage.

Further, in the method for analyzing transuranic nuclides in fecal samples as described above, the digestion treatment in step S3 specifically includes: putting the ash sample after carbonization and ashing into a microwave digestion apparatus for digestion.

Further, in the method for analyzing transuranic nuclides in feces as described above, nitric acid is used for acidity modulation in step S3.

Further, the method for analyzing transuranic nuclides in the stool sample as described above, the specific steps in step S4 include:

S401. Put the prepared feed liquid into the sample tube, and then put the sample tube containing the feed liquid into the sample tube rack of the automatic separation and purification device;

S402. Put the required reagents into the corresponding reagent bottles in the automatic separation and purification device, put the tip into the tip rack; move the extraction column rack to the leftmost end, and fill the required resin into the resin column ;

S403. Turn on the power switch of the automatic separation and purification device, enter the software main interface, and edit the required extraction steps and the parameters of each step;

S404, start the operating system, and start the automatic separation and purification process;

S405. After the operation is finished, take out the sample tube and turn off the power.

Adopt the method described in the present invention, have following remarkable technical effect:

The method of the present invention is based on the self-developed automatic fecal sample sampling device, carbonization and ashing integrated equipment and automatic separation and purification device to carry out feces sample collection, carbonization and ashing treatment, separation and purification, which can simplify and shorten the sampling process and realize The sampling process is standardized to improve the efficiency of feces sampling; the tar, sulfide, char, nitrogen and other odorous gases in the tail gas of the carbonization and ashing of biological samples are removed, the operation of related laboratory facilities is maintained, and the tail gas is prevented from affecting the laboratory and The surrounding air pollution protects the health of analysts and surrounding residents; the use of automatic separation and purification devices instead of manual separation and purification of sample liquid improves the experimental precision, accuracy and efficiency of separation and purification, and reduces the workload of operators .

Description of drawings

Fig. 1 is the flow chart of transuranic nuclide analysis method in the feces sample that provides in the specific embodiment of the present invention;

Fig. 2 is the structural representation of automatic fecal sample sampling device;

Fig. 3 is the structural representation of biological carbonization ashing tail gas treatment system;

Fig. 4 is the structural representation of automatic separation and purification device;

In Figure 2: 1-sample tank tray, 2-tray transmission device, 3-tank bin, 4-sample tank pushing device, 5-infrared position sensor, 6-sitting sampler, 7-capper, 8-cover Warehouse, 9-can lid transmission device;

In Figure 3: 11-instrument door, 12-tail gas inlet, 13-visible window, 14-tail gas outlet, 15-tar treatment system, 16-condensed tail gas outlet, 17-electrostatic decomposition device, 18-activated carbon adsorption device;

In Figure 4: 21-tip rack, 22-sample tube rack, 23-mechanical arm, 24-injection tip, 25-waste tip box, 26-extraction column, 27-waste tank, 28-collection tube shelf.

Detailed ways

The present invention will be further described below in conjunction with specific embodiments and accompanying drawings.

Fig. 1 shows the flow chart of transuranic nuclide analysis method in feces sample of the present invention, comprises the following steps:

S1. Use the automatic fecal sample sampling device to perform automatic fecal sample sampling on the sampled person, and automatically collect the fecal sample in the sample tank.

In this step, the self-developed automatic fecal sample sampling device (patent No. CN110710991B) is used to complete the fecal sample sampling, and its structure is shown in Figure 2. The self-developed automatic fecal sample sampling device is based on the existing toilet and installed an automatic sampling system, which has the main functions of automatic sample collection, sample tank sealing, sample information recording, and temporary storage of sample tanks. In order to avoid cross-contamination of samples, the utensils of each sampler are disposable and easy to handle; the sampling room has simple disinfection and deodorization functions.

The feces samples of those who have not been engaged in radioactivity are collected first, and the feces samples are automatically collected in ceramic sample tanks through the automatic fecal sample sampling device.

The specific steps for collecting fecal samples using an automated fecal sample sampling device are:

S101. Before sampling, clean, dry, number and weigh each of the sample jars and lids, and record the weight of each of the sample jars and lids, and record the weight of each of the sample jars as m ₀ .

Wash the ceramic sample jars with decontamination powder, rinse them with deionized water, and dry them. Mark a certain number on the outside of each sample jar with a pencil, accurately weigh the jar weight m ₀ , and record it in the experiment manual and sample jars. The outer wall records the weight of each sample jar. Clean and dry the lids of a batch of sample jars, weigh them accurately, and record the number and weight on the outer wall with a marker pen.

S102. Put the weighed sample tank into the tank area of the automatic sampling system, put the lid of the weighed sample tank into the cover area, and start sampling the human feces samples.

Before the official sampling, the experimenter will debug and prepare the sample refrigerator, label printer, wastebasket, etc., clean and disinfect the system, and confirm that the system is running normally.

S103. The subject presses the switch of the automatic fecal sample sampling device, and when the sample tank is automatically transferred to the designated position under the toilet, the subject sits down and aligns the anus with the mouth of the tank to start sampling; after the sampling is completed, the sample tank automatically slides away and Cover and seal, and then automatically move to the designated position on the left rear side of the device.

The test subject enters the sampling room, turns on the switch of the sampling device, and waits until the sample tank is automatically transferred to the designated position under the toilet, then the test subject can sit down and point the anus at the mouth of the tank. Before the end of sampling, the subjects should not get up to avoid the sample jar from sliding away automatically. After sampling, the sample jar automatically slides away and is capped and sealed, and then automatically moves to the designated position on the left rear side of the device. The subject manually enters the sample code and prints the label, lifts the sample jar with a sample clip, sticks the label paper to the outer wall of the sample jar, and then puts the sample jar into the refrigerator.

If the inspected person needs to take multiple samples within a certain period of time, just put the same sample tank repeatedly into the last position of the tank, and repeat the above operation each time, all the feces samples can be automatically collected into the same sample tank.

S2. Put the feces sample into the carbonization and ashing integrated equipment for carbonization and ashing to obtain the ash sample.

In this step, the integrated carbonization and ashing equipment is used to complete the carbonization and ashing of fecal samples. The carbonization and ashing integrated equipment includes an ashing furnace and a biocharization and ashing tail gas treatment system (patent number is CN211886157 U). The tail gas generated during the carbonization and ashing process of the ashing furnace is purified, and its structure is shown in Figure 3. The functions of the carbonization and ashing integrated equipment include: dual functions of microwave and auxiliary heating; working temperature 0-900 ℃, which can realize automatic temperature control operation of a series of processes such as evaporation, carbonization and ashing; deodorization and deodorization.

The specific steps for carbonization and ashing of feces samples using integrated carbonization and ashing equipment are as follows:

S201. The experimenter transfers the collected sample from the refrigerator to the laboratory, accurately weighs the total weight m ₁ of the sample jar and the sample, then removes the lid of the sample jar, puts the sample jar into a quartz crucible, and puts the sample jar into a quartz crucible. Put the quartz crucible into the ashing furnace, lower the crucible lid, close the furnace door and lower the thermocouple.

S202, setting experiment parameters. Adjust the heating parameters of the ashing furnace through the touch screen. In this embodiment, set the carbonization temperature to 300°C and run for 10 hours to complete the carbonization; set the ashing temperature to 450°C and run for 12 hours to complete the ashing.

S203. Connect the tail gas port of the ashing furnace to the tail gas inlet of the biocharization and ashing tail gas treatment system, start the automatic ashing process, then start the biocharization and ashing tail gas treatment system, and simultaneously turn on the cooling water circulation system.

S204. The tail gas generated during carbonization and ashing process removes the tar in the tail gas through the tar treatment system, and then enters the electrostatic decomposition device and activated carbon adsorption device through the condensed tail gas outlet to remove the sulfide, carbonization, nitrogen and other malodorous gases in the tail gas. The purified exhaust gas is discharged into the air through the exhaust outlet. The circulating water volume and cooling water temperature can be observed through the visual window.

S205. After the automatic ashing program ends, the ashing furnace continues to run for a period of time. In this embodiment, it is set to continue running for half an hour, and then turn off the power of the ashing furnace and the biochar ashing tail gas treatment system in turn, and keep the ashing furnace door closed. state until it cools down to room temperature naturally. Open the door of the ashing furnace, carefully take out the sample jar, weigh the total weight m ₂ of the jar and the sample ash again, and calculate the weight of the sample ash as m=m ₂ −m ₀ . The fecal sample ash was transferred to a glass bottle with a lid and sealed for storage for subsequent experiments.

S3, subjecting the ash sample to digestion treatment and acidity modulation to obtain a feed liquid.

Put the ash sample that has been completely carbonized and ashed into a microwave digestion apparatus for digestion. Microwave digestion can complete the complete digestion of the ash sample within 2 hours. After the digestion was completed, the acidity was adjusted with nitric acid for the next separation and purification test.

S4, separation and purification

In this step, a self-developed automatic separation and purification device (patent No. CN211652295U) is used to separate and purify the feed liquid, and its structure is shown in Figure 4. The automatic separation and purification device is mainly composed of seven parts: power unit, flow control unit, heating unit, robotic arm platform, pipeline system, small column sealing structure, controller and software. The device can automatically carry out the steps of sample loading, rinsing and elution for transuranium nuclides in the feed liquid.

The specific steps for separation and purification using an automatic separation and purification device are:

S401. Put the prepared feed liquid into the sample tube, and then put the sample tube containing the feed liquid into the sample tube rack of the automatic separation and purification device.

S402. Put the required reagents into the reagent bottles in the device, put the tip into the tip rack of the device; move the extraction column rack to the leftmost end, and fill the required resin into the resin column , and install the sealing plug under the resin.

In this example, the reagents required for separation and purification include nitric acid (analytical grade), hydrogen peroxide (analytical grade), phosphoric acid (analytical grade), ammonia (analytical grade), hydrochloric acid (analytical grade) and hydrofluoric acid (analytical grade ).

S403. Turn on the power switch of the automatic separation and purification device, enter the main interface of the software, and edit the required extraction steps and the parameters of each step.

After preparing the required materials, first check the operating environment of the equipment, confirm that the appearance and wiring of the equipment are intact, and turn on the power switch of the device. At this time, the exhaust and lighting functions have been turned on. After entering the correct user name and password, click Login to enter the main interface of the software. Edit the required extraction steps, and edit the parameters of each step in the method content area.

S404, start the operating system, and start the automatic separation and purification process.

After editing the extraction method, return to the main page of the software, select the desired method name and channel, click "Run" on the page, start the operating system, and start the automatic separation and purification process.

S405. After the operation is finished, manually take out the sample tube and turn off the power.

Afterwards, according to the measurement requirements of different nuclides, different devices are selected to measure the samples in the sample tube.

The method for analyzing transuranic nuclides in fecal samples provided by the present invention is based on the self-developed automatic fecal sample sampling device, carbonization and ashing integrated equipment and automatic separation and purification device to carry out feces sample collection, carbonization and ashing treatment, separation and purification, and can Simplify and shorten the sampling process, realize the standardization of the sampling process, and improve the efficiency of feces sampling; remove the tar and odorous gases such as sulfides, chars, and nitrides in the tail gas of the carbonization and ashing of biological samples, and maintain the operation of related laboratory facilities. It prevents the exhaust gas from polluting the laboratory and the surrounding air, and protects the health of analysts and surrounding residents; using an automatic separation and purification device instead of manually completing the separation and purification steps of the sample liquid improves the experimental precision, accuracy and efficiency of separation and purification. The workload of the operator is reduced.

The above-mentioned embodiments are only illustrations of the present invention, and the present invention can also be implemented in other specific ways or other specific forms without departing from the gist or essential features of the present invention. Accordingly, the described embodiments should be considered in all respects as illustrative and not restrictive. The scope of the present invention should be described by the appended claims, and any changes equivalent to the intention and scope of the claims should also be included in the scope of the present invention.

Claims (7)

1. A transuranic nuclide analysis method in a stool sample, comprising the following steps: S1. Use the automatic fecal sample sampling device to perform automatic fecal sample sampling on the sampled person, and automatically collect the fecal sample in the sample tank; S2. Put the feces sample into the carbonization and ashing integrated equipment for carbonization and ashing treatment to obtain the ash sample; the carbonization and ashing integration equipment includes an ashing furnace and a biocharization and ashing tail gas treatment system, the The tail gas port of the ashing furnace is connected to the tail gas inlet of the biocharization and ashing tail gas treatment system; the carbonization and ashing of the feces are realized through the microwave heating of the ashing furnace, and the biocharization and ashing tail gas treatment system is realized. Purification of exhaust gas during carbonization and ashing; the specific steps of carbonization and ashing include: S201. Weigh the total weight _m1 of the sample tank and the feces in it, then remove the cover of the sample tank, put the sample tank into a quartz crucible, and then put the quartz crucible into an ashing furnace middle; S202. Setting various heating parameters of the ashing furnace; S203, sequentially start the automatic ashing program of the ashing furnace and the biochar ashing tail gas treatment system, and simultaneously open the cooling water circulation system to start carbonization and ashing treatment; S204. The tail gas generated during the carbonization and ashing processes is used to remove tar and malodorous gases in the tail gas through the biocharization and ashing tail gas treatment system, and the purified tail gas is discharged into the air through the tail gas outlet; S205. After the automatic ashing program ends, keep the ashing furnace running for a preset time, then turn off the power supplies of the ashing furnace and the biochar ashing tail gas treatment system in turn, and keep the ashing furnace door closed, Cool down to room temperature naturally; open the door of the ashing furnace, take out the sample tank, weigh the total weight m ₂ of the sample tank and the sample ash again, and finally calculate the weight m of the sample ash; S3, subjecting the ash sample to digestion treatment and acidity modulation to obtain a feed liquid; S4. Use an automatic separation and purification device to separate and purify the feed liquid to obtain a sample. The specific steps are: S401. Put the prepared feed liquid into the sample tube, and then put the sample tube containing the feed liquid into the sample tube rack of the automatic separation and purification device; S402. Put the required reagents into the corresponding reagent bottles in the automatic separation and purification device, put the tip into the tip rack; move the extraction column rack to the leftmost end, and fill the required resin into the resin column ; S403. Turn on the power switch of the automatic separation and purification device, enter the software main interface, and edit the required extraction steps and the parameters of each step; S404, start the operating system, and start the automatic separation and purification process; S405. After the operation is finished, take out the sample tube and turn off the power supply; S5. Selecting different equipment to measure the sample according to the measurement requirements of different nuclides. 2. transuranic nuclide analysis method in feces sample according to claim 1, is characterized in that, in step S1, concrete steps comprise: S101. Before sampling, clean, dry, number and weigh each of the sample jars and lids, and record the weight of each of the sample jars and lids, and record the weight of each of the sample jars as m ₀ ; S102. Put the weighed sample tank into the tank area of the automatic fecal sample sampling device, and put the weighed sample tank lid into the cover area; S103. The subject presses the switch of the automatic fecal sample sampling device, and when the sample tank is automatically transferred to the designated position under the toilet, the subject sits down and aligns the anus with the mouth of the tank to start sampling; The sample jar is automatically slid away and sealed with a cap, and then automatically moved to the designated position on the left rear side of the device. 3. The method for analyzing transuranic nuclides in fecal samples according to claim 1, characterized in that the heating parameters in step S202 are set to a carbonization temperature of 300°C, and the carbonization is completed after running for 10 hours, the ashing temperature is 450°C, and the running 12h to complete ashing. 4 . The method for analyzing transuranic nuclides in feces samples according to claim 1 , wherein the formula for calculating the weight of the sample ash in step S205 is: m=m ₂ −m ₀ . 5. The method for analyzing transuranic nuclides in feces samples according to claim 1, characterized in that, after step S205, it further comprises: transferring the feces sample ash to a glass bottle with a cover for sealed storage. 6. The method for analyzing transuranic nuclides in fecal samples according to claim 1, characterized in that the digestion process in step S3 is specifically: putting the ash sample after carbonization and ashing into a microwave digestion apparatus for digestion. 7. The method for analyzing transuranic nuclides in fecal samples according to claim 6, characterized in that, in step S3, nitric acid is used for acidity modulation.

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