A high sample injection efficiency wet injection device and method

Abstract

The present application relates to solution sampling technology, in particular to a high sampling efficiency wet sampling device and method, which is used to solve the technical problems of low efficiency and low sensitivity existing in the prior art wet sampling technology. The high sampling efficiency wet sampling device of the present application introduces the unused sample residual liquid in the mist chamber into the nuclide sample solution again through the drain pipe as a compensation solution for recycling, and simultaneously adds the base solution of the nuclide sample solution through the online liquid adding device to keep the nuclide concentration in the solution basically consistent, thereby improving the sampling efficiency of the nuclide sample solution, effectively ensuring the stability of the measurement signal intensity, improving the measurement sensitivity and precision, and providing technical support for high precision analysis, and can be applied in the fields of solution sampling, nuclide or isotope analysis such as inductively coupled plasma mass spectrometer, inductively coupled plasma spectrometer, microwave plasma mass spectrometer or spectrometer.

Description

TECHNICAL FIELD

[0001] The present application relates to a solution sampling technology, in particular to a high sampling efficiency wet sampling device and method. BACKGROUND

[0002] In the laboratory and scientific research field, nuclides are usually in the form of solution, and the solution sampling technology is one of the important technical links in the analysis and testing system, which has a wide application in the analysis and testing field of mass spectrometer, spectrometer, chromatograph and the like. The solution sample is introduced into some testing instruments for measurement, such as inductively coupled plasma mass spectrometer and spectrometer commonly used in inorganic and isotope analysis field, to obtain the element content, isotope ratio or molecular information in the solution sample.

[0003] The traditional solution sample sampling method mainly includes wet sampling and dry sampling. The wet sampling generally atomizes the solution sample into mist droplets through a concentric atomizer, and the carrier gas introduces the mist droplets smaller than a certain particle size into the instrument, and the mist droplets larger than a certain particle size are settled and adsorbed on the wall of the mist chamber. In the process of continuous sampling and measurement of the solution sample, only a small proportion of small mist droplets can be used by the sampling system of the instrument, and the large mist droplets are discharged as waste liquid. Although the wet sampling has been improved many times, including the improvement of the configuration of the concentric atomizer and the mist chamber, the use of concentric atomizer and ultrasonic concentric atomizer technology, and the condensation method based on mist chamber cooling to improve the atomization efficiency, the solution sample sampling efficiency of the wet sampling is still low, only 6% to 10%, and the method has low sensitivity. Improving the sampling efficiency of the solution sample can not only greatly reduce the sampling demand and improve the economic benefit in conventional analysis, but also determine the feasibility of the measurement method in the ultra-trace analysis field due to the extremely low sample amount. Dry sampling includes high-temperature desolvation and membrane desolvation technologies. Among them, the membrane desolvation technology has been successful in commercialization. It uses the difference in the selective permeability of the membrane to each component in the mixture to realize separation, purification and concentration technology. The separation of nuclides in the solution sample and water matrix can introduce the nearly dry sample-containing aerosol into the ICP, so that the sampling efficiency of the solution sample can reach 80% to 100%, and the method has the significant feature of high sensitivity and can effectively reduce the interference of O and H complex ions. However, due to the significant memory effect in the sampling process of the membrane desolvation technology, the organic membrane used for desolvation (mainly water and nitric acid matrix) is difficult to clean after being contaminated. In addition, the signal stability of the solution sample in the membrane desolvation technology is affected by many factors such as purge gas and sample carrier gas and high temperature, and the signal fluctuation is large, which seriously affects the measurement precision. SUMMARY

[0004] The present application aims at the problems of low efficiency and low sensitivity of the existing wet sampling technology and the problems of difficult cleaning and low measurement precision of the existing dry sampling technology, and provides a wet sampling device and method with high sampling efficiency.

[0005] In order to achieve the above-mentioned purpose, the technical solution of the present application is as follows:

[0006] A wet sampling device with high sampling efficiency, characterized in that it comprises a sample container, a sampling tube, a concentric atomizer, a mist chamber, a testing instrument, a liquid discharge pipe, an online liquid adding device, a base solution and a solution mixing device.

[0007] The sample container is used for containing a nuclide sample solution.

[0008] One end of the sampling tube is located below the liquid level of the nuclide sample solution in the sample container and close to the bottom, and the other end is connected to the first inlet end of the concentric atomizer.

[0009] The concentric atomizer is used for atomizing the nuclide sample solution delivered by the sampling tube into mist droplets, and the outlet end thereof is connected to the inlet end of the mist chamber; the second inlet end of the concentric atomizer is used for loading inert gas.

[0010] The mist chamber is provided with a sampling port on the side wall thereof, and the testing instrument is located outside the sampling port and is used for loading part of the atomized mist droplets into the testing instrument for analysis and testing by means of inert gas.

[0011] The mist chamber is provided with a liquid discharge port at a lower position of the side wall thereof; one end of the liquid discharge pipe is communicated with the mist chamber through the liquid discharge port, and the other end is located above the liquid level of the sample container and is used for delivering the mist droplets not loaded into the testing instrument as a compensation solution into the sample container to mix with the nuclide sample solution.

[0012] The base solution is a base solution of the nuclide sample solution, one end of the online liquid adding device is provided in the base solution, and the other end is communicated with the liquid discharge pipe or is located above the liquid level of the sample container.

[0013] The solution mixing device is used for uniformly mixing the solutions in the sample container.

[0014] Further, the online liquid adding device comprises a liquid adding pipeline and a first peristaltic pump arranged on the liquid adding pipeline.

[0015] One end of the liquid adding pipeline is provided in the base solution, and the other end is communicated with the liquid discharge pipe or is located above the liquid level of the sample container.

[0016] The first peristaltic pump is used for making the matrix solution enter the liquid adding pipeline and realizing solution transportation in the liquid adding pipeline.

[0017] The liquid discharging pipe is provided with a second peristaltic pump.

[0018] The second peristaltic pump is used for realizing solution transportation in the liquid discharging pipe.

[0019] Further, the inert gas is argon or helium.

[0020] The matrix solution is nitric acid, or hydrochloric acid, or a mixture of nitric acid and a small amount of hydrofluoric acid.

[0021] The solution mixing device is an ultrasonic device or a mechanical vibration device.

[0022] Further, a sampling disc and a mechanical arm are further included.

[0023] The sampling disc is provided with at least one sample site, at least one cleaning site and at least one waste liquid site, which are used for respectively placing a sample containing device, a cleaning bottle and a waste liquid bottle.

[0024] The execution end of the mechanical arm is connected with the sample inlet pipe and the liquid discharging pipe respectively, and is used for driving the sample inlet pipe and the liquid discharging pipe to move in three dimensions.

[0025] The application further provides a high sample inlet efficiency wet method for sampling, which is characterized by comprising the following steps.

[0026] Step 1, building the above-mentioned high sample inlet efficiency wet method for sampling device;

[0027] Step 2, setting the sample inlet time length of the nuclide sample solution;

[0028] Step 3, atomizing the nuclide sample solution transported by the sample inlet pipe into mist drops in the mist chamber through the concentric atomizer, and loading the inert gas through the concentric atomizer, the inert gas loads part of the mist drops in the mist chamber into the testing instrument for analysis and testing, and the rest of the mist drops are discharged from the mist chamber as compensation solution;

[0029] Step 4, transporting the discharged compensation solution to the nuclide sample solution in the sample containing device through the liquid discharging pipe, and adding the matrix solution of the nuclide sample solution quantitatively and at a constant speed to balance the concentration of the compensation solution, so that the three solutions are mixed online to obtain the mixed nuclide sample solution; the addition amount of the matrix solution per unit time is obtained according to the discharge amount of the compensation solution per unit time, the proportion of the nuclide sample in the compensation solution and the proportion of the nuclide sample in the original nuclide sample solution;

[0030] In step 5, the mixed nuclide sample solution is used as the online nuclide sample solution for sampling and analysis, and steps 3 and 4 are repeated until the set sampling time is reached, completing the wet sampling of the nuclide sample solution.

[0031] Furthermore, in step 4, the discharged compensation solution is transported to the nuclide sample solution in the sample holding device through the discharge pipe, and the matrix solution of the nuclide sample solution is added quantitatively and at a constant speed. Specifically:

[0032] First, the matrix solution of the nuclide sample solution is quantitatively and constantly delivered to the discharge pipe through the liquid adding pipe, and mixed with the compensation solution in the discharge pipe to obtain a mixed compensation solution; then the mixed compensation solution is delivered to the nuclide sample solution in the sample holding device through the discharge pipe.

[0033] Further, specifically:

[0034] The nuclide sample solution in the sample holding device is pre-enriched to partially evaporate the matrix solution in the nuclide sample solution, and the injection speed of the nuclide sample solution and the compensation speed of the compensation solution are adjusted to make the injection time of the nuclide sample solution consistent with the injection time of the original nuclide sample solution, wherein the injection time of the original nuclide sample solution is the injection time when the residual liquid is not added to the nuclide sample solution as a supplementary solution in the traditional way.

[0035] Furthermore, step 2 is specifically as follows:

[0036] By adjusting the injection speed of the nuclide sample solution and the compensation speed of the compensation solution, the injection time of the nuclide sample solution is increased to 6 to 10 times the injection time of the original nuclide sample solution.

[0037] Furthermore, in step 4, the ratio of the amount of the matrix solution added per unit time to the amount of the compensation solution discharged per unit time is in the range of 1:8 to 1:12.

[0038] Furthermore, in step 3, the inert gas is argon or helium;

[0039] In step 4, the matrix solution is nitric acid, hydrochloric acid, or a mixture of nitric acid and a small amount of hydrofluoric acid;

[0040] The three solutions are mixed online by ultrasonic vibration or mechanical vibration;

[0041] The ratio of the amount of the matrix solution added per unit time to the amount of the compensation solution discharged per unit time is in the range of 1:10.

[0042] The beneficial effects of the present invention compared to the prior art are as follows:

[0043] 1. The wet sampling device with high sampling efficiency provided by the application, through the liquid discharge pipe, unused sample residual liquid in the mist chamber is introduced into the nuclide sample solution again as a compensation solution for recycling, and at the same time, the online liquid adding device is used to add the base solution of the nuclide sample solution online, so that the nuclide concentration in the solution is basically consistent, which not only improves the sampling efficiency of the nuclide sample solution, i.e. the wet sampling efficiency of the nuclide sample solution is increased from 6% to 10% to more than 95% (theoretically, it can be infinitely close to 100%), but also effectively ensures the stability of the measurement signal intensity, improves the measurement sensitivity and precision, reduces the detection limit, and provides technical support for high-precision analysis, and can be applied to the fields of solution sampling, nuclide or isotope analysis of inductively coupled plasma mass spectrometers, inductively coupled plasma spectrometers, microwave plasma mass spectrometers or spectrometers.

[0044] 2. The wet sampling device with high sampling efficiency provided by the application has simple structure and is convenient to use, the liquid adding pipeline of the online liquid adding device is communicated with the liquid discharge pipe at the other end port, the base solution and the compensation solution are mixed in the liquid discharge pipe first to balance the concentration of the compensation solution, then the mixed compensation solution is added to the nuclide sample solution for ultrasonic online mixing, which can effectively shorten the mixing time of the ultrasonic wave and avoid the non-uniform distribution of the nuclide in the solution, thereby ensuring the signal stability and improving the measurement precision.

[0045] 3. The mechanical arm and the sampling disc are matched to realize fully automatic wet sampling, and the labor cost is greatly saved.

[0046] 4. The wet sampling method with high sampling efficiency provided by the application can significantly improve the measurement precision level by pre-enriching and keeping the sampling time unchanged or increasing the sampling time under the condition of limited sample amount, and is particularly suitable for analysis scenes with limited nuclide sample amount and high testing requirements, such as ultratrace nuclide analysis scenes; compared with dry sampling, the method has the advantages of convenient cleaning, small memory effect influence and stable signal, and provides a prerequisite guarantee for high-precision testing.

[0047] 5. The method can greatly improve the signal intensity by pre-enriching the nuclide sample solution, thereby improving the measurement precision level; or under the condition that the signal intensity remains basically similar, the measurement precision level of the nuclide sample solution can be effectively ensured by increasing the testing time of the nuclide sample solution. DETAILED DESCRIPTION

[0048] Figure 1 It is a structure schematic view of an embodiment of the wet sampling device with high sampling efficiency provided by the application.

[0049] Figure 2 This is a schematic diagram of a high-efficiency wet sampling device during cleaning according to an embodiment of the present invention;

[0050] Figure 3 This is a schematic diagram of an embodiment of a wet method sample introduction device with high sample introduction efficiency according to the present invention, which uses a robotic arm to achieve automatic sample introduction;

[0051] Figure 4 It is a structural schematic diagram of a sampling disk in an embodiment of a wet sampling device with high sampling efficiency of the present invention.

[0052] The specific reference numerals are as follows:

[0053] 1-sample holding device; 2-sample injection tube; 3-concentric nebulizer; 4-spray chamber; 5-testing instrument; 6-drain pipe; 7-online liquid adding device, 71-liquid adding pipeline, 72-first peristaltic pump; 8-matrix solution; 9-solution mixing device; 10-fixed rack; 11-cleaning bottle; 12-waste liquid bottle; 13-sampling tray, 131-sample position, 132-cleaning position, 133-waste liquid position; 14-second peristaltic pump; 15-robotic arm. DETAILED DESCRIPTION

[0054] In order to make the advantages and features of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0055] A wet sampling device with high sampling efficiency, such as Figure 1 As shown, it includes a sample holding device 1, a sample injection tube 2, a concentric atomizer 3, a spray chamber 4, a testing instrument 5, a liquid discharge tube 6, an online liquid adding device 7, a matrix solution 8 and a solution mixing device 9. The wet sampling device in this embodiment is a manual sampling device.

[0056] The sample holding device 1 is used to hold the radionuclide sample solution. It can be a commercial small-diameter sample bottle (tube) or a professionally designed sample tube. In this embodiment, the professionally designed sample tube has an inner diameter of approximately 3 mm and a slightly tapered bottom. This facilitates the collection of the compensation solution, the online addition of the matrix solution 8, and the online uniform mixing of the three solutions. During use, the sample tube is secured by a holder 10.

[0057] One end of the sample introduction tube 2 is located below the liquid level of the nuclide sample solution in the sample container 1 near the bottom, and the other end is connected to the first inlet end of the concentric nebulizer 3. The concentric nebulizer 3 is used to atomize the nuclide sample solution delivered by the sample introduction tube 2 into mist droplets, and at the same time, the second inlet end of the concentric nebulizer is used to load argon gas, and the outlet end of the concentric nebulizer 3 is connected to the inlet end of the mist chamber 4. The side wall of the mist chamber 4 is provided with a sampling port, and the test instrument 5 in this embodiment is a mass spectrometer, which is located outside the sampling port and is used to load small mist droplets smaller than a certain particle size into the mass spectrometer through argon gas for analysis and processing. The lower part of the side wall of the mist chamber 4 is provided with a liquid discharge port, and one end of the liquid discharge tube 6 communicates with the mist chamber 4 through the liquid discharge port, and the other end is located above the liquid level of the nuclide sample solution in the sample container 1, which is used to deliver the mist droplets that are not loaded into the mass spectrometer, i.e. large mist droplets larger than a certain particle size, as a compensation solution through the liquid discharge tube 6 to the sample container 1 to mix with the nuclide sample solution for recycling. Specifically, the outer side of the liquid discharge tube 6 is provided with a second peristaltic pump 14 for delivering the solution in the liquid discharge tube 6.

[0058] The online liquid adding device 7 includes a liquid adding pipeline 71 and a first peristaltic pump 72 arranged outside the liquid adding pipeline. In this embodiment, the liquid discharge tube 6 is a three-way tube, one end of the liquid adding pipeline 71 is arranged in the base solution 8 of the nuclide sample solution, and the other end communicates with the third port of the liquid discharge tube 6, so that the compensation solution is mixed with the base solution 8 before being delivered to the sample container 1 to balance the concentration of the compensation solution. The first peristaltic pump 72 is used to deliver the base solution 8 into the liquid adding pipeline 71 and realize the delivery of the solution in the liquid adding pipeline 71. Among them, the base solution 8 of the nuclide sample solution is usually 2% nitric acid, 5% nitric acid, 2% hydrochloric acid or a mixture of nitric acid and a small amount of hydrofluoric acid.

[0059] The solution mixing device 9 is used to mix the three solutions uniformly, i.e. to make the nuclide uniformly distributed in the solution, after the mixed solution of the compensation solution and the base solution 8 is delivered to the sample container 1. The online mixing of the solution can be mechanical shaking, ultrasonic shaking, microwave shaking, etc., as long as the online mixing of the solution is realized quickly under the condition that the liquid level of the sample solution does not fluctuate violently. If mechanical shaking is used for mixing, the relative positions of the sample container, the sample introduction tube port, the liquid discharge tube port and the liquid adding port should remain unchanged and not be dislocated during the solution shaking process. In this embodiment, the solution mixing device 9 is an ultrasonic wave, which is used to mix the solution in the sample container online through ultrasonic shaking.

[0060] In other embodiments of the present application, the other end port of the liquid feeding pipe 71 can also be located above the level of the nuclide sample solution in the sample holding device 1 for directly adding the compensation solution and the base solution 8 into the sample tube 2 respectively and then mixing on line, but compared with the embodiment of mixing the compensation solution and the base solution 8 first and then delivering them together to the sample holding device 1, the on-line mixing time in the sample holding device 1 is increased, therefore, the mixing method in the embodiment is preferred.

[0061] In use, after the sample holding device 1, the sample tube 2, the liquid discharging pipe 6 and the liquid feeding pipe 71 are set, they are fixed by using special buckles respectively to keep the relative positions of the sample tube 2, the liquid discharging pipe 6 and the liquid feeding pipe 71 with the sample holding device 1 unchanged. The first peristaltic pump 72 is started according to the set delay time to add the 2% nitric acid solution into the liquid feeding pipe 71 at a set speed, and the solution in the sample holding device is mixed on line by ultrasonic oscillation to ensure that the compensation solution, the base solution and the remaining nuclide sample solution are mixed on line uniformly.

[0062] As shown in Figure 2 , when the circulating sample introduction is nearly completed, the whole device needs to be cleaned. First, the sample tube 2 is taken out of the sample holding device 1 and placed below the liquid level of the cleaning liquid in the cleaning bottle 11. Usually, the cleaning liquid is the base solution of the nuclide sample solution. For example, if the base solution 8 of the nuclide sample solution is 2% nitric acid solution, the cleaning liquid is also 2% nitric acid solution or a nitric acid solution with a higher concentration such as 3% to 5%. At the same time, the port of the liquid discharging pipe 6 on the sample holding device 1 is transferred to above the liquid level of the waste liquid bottle 12. The cleaning liquid continuously enters the inside of the device, and the mist droplets of the cleaning liquid after atomization take the same route as the mist droplets of the nuclide sample solution after atomization. At this time, the nuclide signal intensity measured by the observation test instrument is observed until the signal intensity reaches or approaches the background level. If the cleaning is not clean for a long time, the cleaning liquid can be replaced or 2 to 3 cleaning bottles can be set, for example, 5% nitric acid solution is prepared in the second cleaning bottle and 2% nitric acid cleaning liquid is prepared in the third cleaning bottle. The cleaning liquids are fed in turn until the signal intensity reaches or approaches the background level. Generally, 5 to 10 minutes of cleaning can meet the analysis requirements. After judging that the cleaning is complete, the next nuclide sample solution starts to be introduced for analysis. The sample introduction-cleaning steps are iterated until the analysis of all samples is completed.

[0063] As shown in Figure 3 , Figure 4 , the wet sample introduction device of the present application can also use a mechanical arm 15 to realize automatic sample introduction, Figure 3For simplifying the schematic diagram, the concentric nebulizer 3, the mist chamber 4, the testing instrument 5, the online liquid adding device 7, the base solution 8 and the solution mixing device 9 are not shown. The automatic sampling wet sampling device is provided with a sampling disc 13, the sampling disc 13 is provided with 24 sample positions 131, 3 cleaning positions 132 and a plurality of waste liquid positions 133, in the embodiment, a mechanical arm 15 is adopted, the execution end of the mechanical arm 15 is connected with the sampling tube 2 and the liquid discharge tube 6 respectively, and is used for driving the sampling tube 2 and the liquid discharge tube 6 to move in the vertical direction, the horizontal direction and the front-back direction. Specifically, when the next nuclide sample solution is sampled and analyzed, the sampling tube 2 and the liquid discharge tube 6 can be moved to different sample positions 131 by the mechanical arm 15, or when the analysis is completed, the sampling tube 2 is moved to the cleaning position 132 by the mechanical arm 15, and the liquid discharge tube 6 is moved to the waste liquid position 133. In other embodiments of the present application, one sample position 131 can also be arranged on the sampling disc 13, and the sample tube on the sample position 131 is manually replaced after each sample analysis is completed.

[0064] Based on the high sampling efficiency wet sampling device, the present application further provides a high sampling efficiency wet sampling method, which specifically comprises the following steps:

[0065] Step 1, building the high sampling efficiency wet sampling device.

[0066] Step 2, setting the sampling time length of the nuclide sample solution. Specifically, before the nuclide sample solution is analyzed, the nuclide sample solution in the sample container is pre-enriched, so that the base solution part in the nuclide sample solution is evaporated, for example, the volume of the nuclide sample solution is evaporated from more than 3 milliliters to 300-500 microliters by using constant temperature heating, and by adjusting the sampling speed of the nuclide sample solution, the sampling time length of the nuclide sample solution is kept unchanged or similar to the original nuclide sample solution sampling time length, so that the signal intensity is improved by 6-10 times, and then higher precision measurement results are obtained; in other embodiments of the present application, other pre-enrichment methods can also be used to reduce the volume of the nuclide sample solution. In addition, the nuclide sample solution can also be directly sampled and measured, at this time, by adjusting the sampling speed of the nuclide sample solution and the compensation speed of the compensation solution, the sampling time length of the nuclide sample solution is increased to 6-10 times of the original nuclide sample solution sampling time length, under the condition that the signal intensity is basically similar, by increasing the testing time of the nuclide sample solution, the measurement precision level of the nuclide sample solution can be ensured.

[0067] Step 3, the nuclide solution sample delivered by the sample injection tube 2 is atomized into mist droplets in the mist chamber 4 through the concentric atomizer 3, and the mist droplets after atomization realize selective separation of small and large mist droplets in the mist chamber 4. Specifically, argon is loaded through the concentric atomizer 3, and the argon with a certain flow rate enters the mist chamber 4, and the small mist droplets smaller than a certain particle size are loaded into the ion (or atom) source area of the test instrument 5, such as the ion (or atom) source area of a mass spectrometer, a spectrometer, a chromatograph, etc. for analysis, and the large mist droplets larger than a certain particle size are discharged from the mist chamber 4 due to gravity, forming a residual liquid.

[0068] Step 3, adding the matrix solution 8 of the nuclide sample solution for concentration balance.

[0069] Experiments show that the sample nuclides of interest in the residual liquid are enriched, and their recompensation into the nuclide sample solution will cause local concentration to rise. This phenomenon will lead to two results: one is that the nuclide sample solution is not mixed uniformly, and after sample injection, the measurement signal fluctuates; the other is that the concentration of the nuclides of interest in the nuclide sample solution is generally slowly rising, and the measurement signal as a whole shows a slowly rising trend after sample injection. Both of these two results affect the stability of the measurement signal and cannot be ignored for concentration analysis, although the influence on nuclide concentration ratio or isotope ratio analysis is relatively small, but also affects the precision level of the ratio measurement, therefore, the present application adds the matrix solution 8 of the nuclide sample solution for concentration balance. At the same time, since the enrichment proportion of the sample nuclides in the residual liquid is constant, when it is introduced as a compensation solution, the matrix solution 8 is added quantitatively and at a constant speed, which can effectively balance the enriched compensation solution and maintain the stability of the concentration of the nuclide sample solution.

[0070] Specifically, the matrix solution 8 of the nuclide sample solution is prepared, and the matrix solution 8 is first quantitatively and at a constant speed delivered to the liquid discharge pipe 6 through the liquid feeding pipe 71, mixed with the compensation solution in the liquid discharge pipe 6, to balance the concentration of the compensation solution and obtain a mixed compensation solution. Then the mixed compensation solution is delivered to the nuclide sample solution in the sample container 1, at this time, in order to avoid the non-uniform distribution of the nuclides in the solution, which will affect the signal stability and reduce the measurement precision, online mixing is needed to make the concentration of the mixed nuclide sample solution and the original nuclide sample solution basically consistent, and in the present embodiment, the ultrasonic oscillation method is preferably used for online mixing of the three solutions in the sample container.

[0071] When the matrix solution 8 is added, a delay time such as 10 seconds is set based on the sample solution injection time of the nuclide sample solution, and the matrix solution 8 is added at a constant speed according to the delay time, so that the addition of the compensation solution and the matrix solution 8 in the chamber 4 is synchronized, and the concentration of the nuclide in the solution is kept basically unchanged. The delay time is set according to the model of the chamber 4, the inner diameter and length of the sample tube 2 and the drain tube 6, and it can be tested in advance to achieve the synchronization of the compensation solution introduction and the matrix solution 8 addition.

[0072] At the same time, the addition amount of the matrix solution 8 per unit time is calculated according to the discharge amount of the compensation solution per unit time, the proportion of the nuclide sample in the compensation solution, and the proportion of the nuclide sample in the original nuclide sample solution. The first peristaltic pump 72 for adding the matrix solution 8 online in the application is controlled by the speed difference with the second peristaltic pump for the drain tube 6, combined with the inner diameters of the sample tube 2 and the drain tube 6, to achieve the purpose of adding the matrix solution 8 at a constant speed. Through experiments, it is found that the loss amount of the matrix solution 8 in the residual liquid is usually 1:8-1:12 of the residual liquid discharge amount, and the application can preferably adjust the parameters of the concentric atomizer 3 and argon gas to make the loss amount of the matrix solution 8 in the residual liquid usually 1:10 of the residual liquid discharge amount, and accordingly, the addition amount of the matrix solution 8 per unit time is 1:10 of the discharge amount of the compensation solution per unit time.

[0073] In addition, in other embodiments of the application, the matrix solution 8 and the compensation solution can also be added to the nuclide sample solution in the sample container 1 at the same time, and the mixed nuclide sample solution is obtained after online mixing.

[0074] Step 4: The mixed nuclide sample solution is used as an online nuclide sample solution for injection analysis, and steps 2 and 3 are repeatedly performed, so that the residual liquid is efficiently utilized in the cycle of re-injection, atomization and diversion, and the injection measurement is continuously performed until the set injection time is reached, the compensation solution and the matrix solution 8 are stopped, the injection measurement is stopped, and the wet injection of the nuclide sample solution is completed.

[0075] The above description is only used to illustrate the technical solutions of the application, and is not limited thereto. For ordinary skilled persons in the art, the specific technical solutions described in the above embodiments can be modified, or some technical features can be replaced by equivalents, and these modifications or replacements do not change the essence of the corresponding technical solutions out of the scope of the technical solutions protected by the application.

Claims

1. A wet sampling device with high sampling efficiency, comprising a sample holding device (1), a sampling tube (2), a concentric atomizer (3), a spray chamber (4), a testing instrument (5) and a liquid discharge tube (6), characterized in that: It also includes an online liquid adding device (7), a matrix solution (8) and a solution mixing device (9); The sample holding device (1) is used to hold a nuclide sample solution; one end of the sample injection tube (2) is located below the liquid level of the nuclide sample solution in the sample holding device (1) and close to the bottom, and the other end is connected to the first inlet end of the concentric atomizer (3); The concentric atomizer (3) is used to atomize the nuclide sample solution transported by the sample inlet tube (2) into droplets, and its outlet end is connected to the inlet end of the spray chamber (4); the second inlet end of the concentric atomizer (3) is used to load inert gas; A sampling port is provided on the side wall of the mist chamber (4), and the testing instrument (5) is located outside the sampling port and is used to load part of the atomized small droplets into the testing instrument (5) through inert gas for analysis and testing; A liquid discharge port is provided at a lower position of the side wall of the mist chamber (4); one end of the liquid discharge pipe (6) is connected to the mist chamber (4) via the liquid discharge port, and the other end is located above the liquid level of the sample holding device (1), and is used to transport the droplets not loaded into the test instrument (5) as a compensation solution to the sample holding device (1) for mixing with the nuclide sample solution; The matrix solution (8) is a matrix solution of a nuclide sample solution, one end port of the online liquid adding device (7) is arranged in the matrix solution (8), and the other end port is connected to the drain pipe (6), or the other end port is located above the liquid level of the sample holding device (1); The solution mixing device (9) is used to evenly mix the solution in the sample holding device (1).

2. A wet sampling device with high sampling efficiency according to claim 1, characterized in that: The online liquid adding device (7) comprises a liquid adding pipeline (71) and a first peristaltic pump (72) arranged on the liquid adding pipeline; One end of the liquid adding pipe (71) is disposed in the matrix solution (8), and the other end is connected to the liquid drain pipe (6), or the other end is located above the liquid level of the sample holding device (1); The first peristaltic pump (72) is used to allow the matrix solution (8) to enter the liquid feeding pipe (71) and realize the solution transportation in the liquid feeding pipe (71); A second peristaltic pump (14) is provided on the liquid discharge pipe (6); The second peristaltic pump (14) is used to transport the solution in the discharge pipe (6).

3. A wet sampling device with high sampling efficiency according to claim 2, characterized in that: The inert gas is argon or helium; The matrix solution (8) is nitric acid, hydrochloric acid, or a mixture of nitric acid and hydrofluoric acid; The solution mixing device (9) is an ultrasonic device or a mechanical vibration device.

4. A wet sampling device with high sampling efficiency according to any one of claims 1 to 3, characterized in that: Also included is a sampling tray (13) and a robotic arm (15); The sampling tray (13) is provided with at least one sample position (131), at least one cleaning position (132), and at least one waste liquid position (133), for respectively placing the sample holding device (1), the cleaning bottle, and the waste liquid bottle; The execution end of the mechanical arm (15) is connected to the sample injection tube (2) and the liquid discharge tube (6) respectively, and is used to drive the sample injection tube (2) and the liquid discharge tube (6) to move three-dimensionally.

5. A wet sampling method with high sampling efficiency, characterized in that: The following steps are involved: Step 1, constructing a wet sampling device with high sampling efficiency according to any one of claims 1 to 4; Step 2, setting the injection time of the nuclide sample solution; Step 3, atomizing the nuclide sample solution delivered by the sampling tube (2) into droplets in the spray chamber (4) through the concentric atomizer (3), and loading an inert gas through the concentric atomizer (3), so that the inert gas carries part of the droplets in the spray chamber (4) into the testing instrument (5) for analysis and testing, and the remaining droplets are discharged from the spray chamber (4) as a compensation solution; Step 4, the discharged compensation solution is transported to the nuclide sample solution in the sample holding device (1) through the discharge pipe (6), and the matrix solution (8) of the nuclide sample solution is added quantitatively and at a constant rate to balance the concentration of the compensation solution, and the three solutions are mixed online to obtain a mixed nuclide sample solution; The amount of the matrix solution (8) added per unit time is calculated based on the amount of the compensation solution discharged per unit time, the proportion of the nuclide sample in the compensation solution, and the proportion of the nuclide sample in the original nuclide sample solution; In step 5, the mixed nuclide sample solution is used as the online nuclide sample solution for sampling and analysis, and steps 3 and 4 are repeated until the set sampling time is reached, completing the wet sampling of the nuclide sample solution.

6. A wet sampling method with high sampling efficiency according to claim 5, characterized in that: In step 4, the discharged compensation solution is transported to the nuclide sample solution in the sample holding device (1) through the liquid discharge pipe (6), and the matrix solution of the nuclide sample solution is added quantitatively and at a constant speed. Specifically: First, the matrix solution (8) of the nuclide sample solution is quantitatively and constantly delivered to the discharge pipe (6) through the liquid adding pipe (71), and mixed with the compensation solution in the discharge pipe (6) to obtain a mixed compensation solution; and then the mixed compensation solution is delivered to the nuclide sample solution in the sample holding device (1) through the discharge pipe (6).

7. A wet sampling method with high sampling efficiency according to claim 6, characterized in that: Step 2 is as follows: The nuclide sample solution in the sample holding device (1) is pre-enriched to partially evaporate the matrix solution in the nuclide sample solution, and the injection time of the nuclide sample solution is made consistent with the injection time of the original nuclide sample solution.

8. A wet sampling method with high sampling efficiency according to claim 6, characterized in that: Step 2 is as follows: Increase the injection time of the nuclide sample solution to 6 to 10 times the injection time of the original nuclide sample solution.

9. A wet sampling method with high sampling efficiency according to any one of claims 5 to 8, characterized in that: In step 4, the ratio of the amount of the base solution added per unit time to the amount of the compensation solution discharged per unit time is in the range of 1:8 to 1:

12.

10. A wet sampling method with high sampling efficiency according to claim 9, characterized in that: In step 3, the inert gas is argon or helium; In step 4, the matrix solution (8) is nitric acid, hydrochloric acid, or a mixture of nitric acid and hydrofluoric acid; The three solutions are mixed online by ultrasonic vibration or mechanical vibration; The ratio of the amount of the matrix solution added per unit time to the amount of the compensation solution discharged per unit time is in the range of 1:10.

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