阅读说明：本技术 一种可控温微量高纯液样蒸发装置 (Temperature-controllable trace high-purity liquid sample evaporation device ) 是由 查甫生 王永生 洪玉明 许龙 康博 陈林杰 丁丹 于 2019-09-24 设计创作，主要内容包括：本发明公开了一种可控温微量高纯液样蒸发装置,包括液样注入装置、蒸发装置,集气装置、气样取样装置和抽气装置。本发明中抽气装置能够在蒸发开始前抽出液体蒸发腔和可伸缩集气腔内的气体,保证了蒸发和收集过程中不会有杂质气体掺入,尤其对于微量液体蒸发来说,大大的减少了检测时的干扰。本发明中的蒸发装置主体内壁由耐腐蚀钢材制成,大幅提升了蒸发腔室的温度变化范围,且蒸发腔主体空间由活塞控制,一方面避免了杂质气体的混入,另一方面也提高了安全性。本发明中的集气装置在抽气时,内部气体会被抽气装置抽出,当收集制取气体完成后,可由取样孔完成取样。本发明具有控温范围广、可蒸发微量液体和制取气体纯度高等特点。(The invention discloses a temperature-controllable trace high-purity liquid sample evaporation device which comprises a liquid sample injection device, an evaporation device, a gas collection device, a gas sample sampling device and an air extraction device. The air extractor can extract the air in the liquid evaporation cavity and the telescopic air collecting cavity before evaporation begins, ensures that impurity gas cannot be doped in the evaporation and collection processes, and greatly reduces the interference during detection particularly for trace liquid evaporation. The inner wall of the evaporation device main body is made of corrosion-resistant steel, the temperature change range of the evaporation chamber is greatly enlarged, and the space of the evaporation chamber main body is controlled by the piston, so that impurity gas is prevented from being mixed, and the safety is improved. When the gas collecting device is used for extracting gas, the internal gas can be extracted by the gas extracting device, and after the gas is collected and prepared, the sampling can be completed through the sampling hole. The present invention has the features of wide temperature controlling range, capacity of evaporating trace liquid, high gas purity, etc.)

1. A temperature-controllable trace high-purity liquid sample evaporation device is characterized by comprising an evaporation device, a liquid sample injection device, a gas collection device, a gas sampling device and an air extraction device;

the evaporation device comprises a main body (24) and a piston (1), wherein the main body (24) is a closed circular hollow device, the wall of the circular hollow device is respectively composed of an anti-corrosion steel inner wall (2), a temperature control heating band (3) and a heat insulation layer (4) from inside to outside, the upper part of an inner cavity of the main body (24) is provided with the piston (1), and the top of the piston (1) and the main body (24) form a closed liquid evaporation cavity (10);

the liquid sample injection device consists of a sample injection tube (9) and a sample injection tube switch (7) arranged on the sample injection tube (9), wherein a rubber plug (8) is arranged in the sample injection tube (9), and the sample injection tube (9) passes through the wall of the main body (24) and is communicated with the liquid evaporation cavity (10);

the gas collecting device consists of a steam extracting pipe (18), a steam extracting switch (14) arranged on the steam extracting pipe (18), a one-way valve B (15) arranged on the steam extracting pipe (18) and a telescopic gas collecting cavity (19), wherein one end of the steam extracting pipe (18) penetrates through the wall of the main body (24) to be communicated with the liquid evaporation cavity (10), and the other end of the steam extracting pipe is communicated with the telescopic gas collecting cavity (19);

the gas sampling device consists of a sampling tube (17) and a sampling tube switch (16) arranged on the sampling tube (17), a rubber plug (8) is arranged in the sampling tube (17), and the sampling tube (17) is positioned at the upper part of the telescopic gas collection cavity (19) and communicated with the telescopic gas collection cavity (19);

the air extracting device consists of an air extracting pipe (13), an air extracting pipe branch pipe (25), a one-way valve A (11), a liquid evaporation cavity air extracting switch (12), a one-way valve C (20), a telescopic gas collecting cavity air extracting switch (21) and an air extracting pump (22); one end of the exhaust pipe (13) is communicated with the liquid evaporation cavity (10), the other end is communicated with the exhaust pump (22), one end of the exhaust pipe branch pipe (25) is communicated with the exhaust pipe (13), and the other end is communicated with the telescopic gas collection cavity (19); the check valve A (11) and the liquid evaporation cavity air extraction switch (12) are respectively arranged at the communication part of the air extraction pipe (13) and the liquid evaporation cavity (10), and the check valve C (20) and the telescopic gas collection cavity air extraction switch (21) are respectively arranged at the communication part of the air extraction pipe (13) and the telescopic gas collection cavity (19).

2. A temperature-controllable trace amount high-purity liquid sample evaporation device according to claim 1, wherein the position of the rubber plug (8) in the sampling tube (9) is the outer side of the sampling tube switch (7), namely the position departing from the main body (1); the position of the rubber plug (8) in the sampling tube (17) is above the sampling tube switch (16), namely the position deviating from the telescopic gas collection cavity (19).

3. The evaporation apparatus for micro high purity liquid sample with controllable temperature according to claim 1, wherein the temperature-controlled heating belt (3) is connected with an electric heating device, and the electric heating device comprises a heating belt temperature-controlled regulator (5).

4. The evaporation device of claim 1, wherein the retractable gas collection chamber (19) is a replaceable component, and the size of the retractable gas collection chamber (19) is customized according to the volume of the liquid sample to be evaporated.

Technical Field

The invention relates to the technical field of environmental geotechnics, in particular to an experimental device which can evaporate trace liquid samples, has high purity of produced gas samples, is free of impurity gases and has a wide controllable evaporation temperature range.

Background

In recent years, with the development of the Chinese economic society, the rapid development of the urbanization process, the adjustment of the national industrial layout and the implementation of the policy of 'move back to the third place', a large number of industrial and enterprise polluted sites left by relocation or abandonment of industrial enterprises located in urban centers and suburbs are re-developed into human living environments. Due to the discharge of industrial three wastes and the reasons of leakage, overflow, dripping, leakage and the like in the production process, a large amount of toxic and harmful substances enter soil and underground water.

In addition, the problem of groundwater pollution caused by leachate leakage of urban domestic refuse landfills is very serious, almost all cities are surrounded by the refuse landfills, and most of the refuse landfills constructed before have no effective sanitary protection measures, so that the common problem of shallow groundwater pollution is caused. And problems such as leakage of underground oil storage tanks of a plurality of gas stations in a city, leakage of sewage discharge pipelines and the like are common, so that underground water is polluted. Forming a plurality of polluted sites.

China still starts to repair soil and underground water due to economic and technical limitations. Soil and groundwater remediation technologies can be generally classified into two major categories, ectopic treatment technologies and in-situ treatment technologies. The most common of the ectopic repair techniques is the extraction process technique. Groundwater aeration is the most common method of in situ remediation. The contaminants are volatilized and carried to the aeration zone and then removed by the vapor extraction system.

However, gas chromatography is always used as the primary method for detecting contaminant concentrations in any technique.

In the above technology, after sampling is needed for indexes such as pollutant repairing effect, the quantitative index can be obtained by measuring with a gas chromatography, but the gas chromatograph detects gas samples, and the taken samples to be detected are all water samples and cannot be directly measured. In the conventional method, a sample is evaporated and then sent to a gas chromatograph for measurement, but air cannot be isolated, so that the obtained gas sample is mixed gas formed by steam and air prepared from the liquid sample, the measured result is difficult to avoid generating errors, and particularly when the liquid sample is trace liquid, the errors are increased rapidly and interfere with the experimental result.

Therefore, the preparation of high purity gas samples is a key requirement for reducing detection errors.

Disclosure of Invention

The invention aims to prepare a high-purity gas sample without impurities aiming at a trace liquid sample.

The invention aims to realize the following technical scheme, and provides a temperature-controllable trace high-purity liquid sample evaporation device which comprises an evaporation device, a liquid sample injection device, a gas collection device, a gas sampling device and an air extraction device;

the evaporation device comprises a main body and a piston, wherein the main body is a closed circular hollow device, the wall of the circular hollow device is respectively composed of an anti-corrosion steel inner wall, a temperature control heating belt and a heat insulation layer from inside to outside, the upper part of an inner cavity of the main body is provided with the piston, and the top of the piston and the main body form a closed liquid evaporation cavity;

the liquid sample injection device consists of a sample injection tube and a sample injection tube switch arranged on the sample injection tube, wherein a rubber plug is arranged in the sample injection tube, and the sample injection tube passes through the wall of the main body and is communicated with the liquid evaporation cavity;

the gas collecting device consists of a steam extracting pipe, a steam extracting switch arranged on the steam extracting pipe, a one-way valve B arranged on the steam extracting pipe and a telescopic gas collecting cavity, wherein one end of the steam extracting pipe penetrates through the wall of the main body to be communicated with the liquid evaporation cavity, and the other end of the steam extracting pipe is communicated with the telescopic gas collecting cavity;

the gas sampling device consists of a sampling tube and a sampling tube switch arranged on the sampling tube, wherein a rubber plug is arranged in the sampling tube, and the sampling tube is positioned at the upper part of the telescopic gas collecting cavity and communicated with the telescopic gas collecting cavity;

the air extracting device consists of an air extracting pipe, an air extracting pipe branch pipe, a one-way valve A, a liquid evaporation cavity air extracting switch, a one-way valve C, a telescopic air collecting cavity air extracting switch and an air extracting pump; one end of the exhaust pipe is communicated with the liquid evaporation cavity, the other end of the exhaust pipe is communicated with the exhaust pump, one end of the branch pipe of the exhaust pipe is communicated with the exhaust pipe, and the other end of the branch pipe of the exhaust pipe is communicated with the telescopic gas collecting cavity; the one-way valve A and the liquid evaporation cavity air exhaust switch are respectively arranged at the communication part of the air exhaust pipe and the liquid evaporation cavity, and the one-way valve C and the telescopic gas collection cavity air exhaust switch are respectively arranged at the communication part of the air exhaust pipe and the telescopic gas collection cavity.

Preferably, the position of the rubber plug in the sampling tube is the outer side of the sampling tube switch, namely the position departing from the main body; the position of the rubber plug in the sampling tube is above the switch of the sampling tube, namely the position deviating from the telescopic gas collection cavity.

Preferably, the temperature-controlled heating belt is electrically connected with an electric heating device, and the electric heating device comprises a heating belt temperature-controlled regulator.

Preferably, the telescopic gas collecting cavity is a replaceable part, and the size of the telescopic gas collecting cavity is customized according to the volume of the liquid sample to be evaporated.

Compared with the prior art, the invention has the beneficial effects that:

1. by adopting the corrosion-resistant steel inner wall, the evaporation temperature range of the liquid sample is greatly improved, and the evaporation requirements of various liquid samples can be met.

2. The mode that the switch is used with the check valve is adopted, the sealing performance of the device is improved, and the possibility of reverse leakage of gas is reduced.

3. Before formal evaporation, an air extractor is used for extracting air, so that the purity of the final gas sample is ensured, the detection interference is reduced, and the experimental error is reduced.

4. The size of the liquid evaporation chamber is automatically adjusted by the piston according to the volume of gas in the chamber, so that the risk of air mixing is reduced, and the purity of a gas sample is ensured.

5. The gas sample preparation device has no interference of impurity gas, so that the detection requirement of preparing a gas sample from a trace liquid sample can be met.

Drawings

FIG. 1 is a schematic diagram of the apparatus of the present invention.

FIG. 2 is a schematic view of the structure of the liquid sample injection device.

Fig. 3 is a schematic structural diagram of a gas sampling device.

Fig. 4 is an enlarged schematic view of the groove structure on the outer side of the top of the piston.

In the figure: 1. a piston; 2. a corrosion-resistant steel inner wall; 3. a temperature controlled heating zone; 4. a heat insulation layer; 5. a heating belt temperature control regulator; 6. a piston seal ring; 7. a sample inlet pipe switch; 8. a rubber plug; 9. a sample inlet pipe; 10. a liquid evaporation chamber; 11. a one-way valve A; 12. a liquid evaporation cavity air extraction switch; 13. an air exhaust pipe; 14. a vapor extraction switch; 15. a check valve B; 16. a sampling tube switch; 17. a sampling tube; 18. a vapor extraction tube; 19. a telescopic gas collection cavity; 20. a check valve C; 21. a telescopic gas collection cavity air extraction switch; 22 a suction pump; 23. a base; 24. a main body; 25. an exhaust pipe branch pipe; 26. and (4) a groove.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

As can be seen from fig. 1, 2, 3 and 4, the invention provides a temperature-controllable trace high-purity liquid sample evaporation device, which comprises an evaporation device, a liquid sample injection device, a gas collection device, a gas sampling device and an air extraction device.

The vaporizing device includes a main body 24 and a piston 1. The main body 24 is a closed circular hollow device, and the wall of the circular hollow device is respectively composed of an anti-corrosion steel inner wall 2, a temperature control heating belt 3 and a heat insulation layer 4 from inside to outside. A piston 1 is arranged at the upper part of the inner cavity of the main body 24, and the top of the piston 1 and the main body 24 form a closed liquid evaporation cavity 10. The 24 inlayers of main part adopt corrosion-resistant steel inner wall 2, can greatly increased temperature control range of variation, and adopt heat preservation insulating layer 4 outermost, enable the interior temperature of cavity more stable, and can prevent to scald, increase the security.

In this embodiment, the top of the piston 1 is a cylinder, and a groove 26 is left at the center of the outer side of the cylinder, and the piston seal ring 6 is installed in the groove. The piston seal ring 6 can prevent gas in the liquid evaporation chamber 10 from leaking and external gas from entering.

In this embodiment, the temperature-controlled heating belt 3 is electrically connected to an electric heating device including a temperature-controlled regulator 5.

In this embodiment, the main body 24 is seated on the base 23.

The liquid sample injection device consists of a sample injection tube 9 and a sample injection tube switch 7 arranged on the sample injection tube 9, wherein a rubber plug 8 is arranged in the sample injection tube 9, and the sample injection tube 9 passes through the wall of the main body 24 and is communicated with the liquid evaporation cavity 10. In this embodiment, the position of rubber buffer 8 in advancing appearance pipe 9 is the outside of advancing appearance pipe switch 7, deviates from the position of main part 1 promptly, and there is gaseous the spilling when the design of rubber buffer 8 can effectively avoid injecting liquid leakage and liquid evaporation.

The gas collecting device consists of a steam extraction pipe 18, a steam extraction switch 14 arranged on the steam extraction pipe 18, a one-way valve B15 arranged on the steam extraction pipe 18 and a telescopic gas collecting cavity 19, wherein one end of the steam extraction pipe 18 penetrates through the wall of the main body 24 to be communicated with the liquid evaporation cavity 10, and the other end of the steam extraction pipe is communicated with the telescopic gas collecting cavity 19. In this embodiment, the retractable gas collecting chamber 19 is a replaceable component, and is sized according to the volume of the liquid sample to be evaporated.

The gas sampling device comprises a sampling tube 17 and a sampling tube switch 16 arranged on the sampling tube 17, wherein a rubber plug 8 is arranged in the sampling tube 16, and the sampling tube 17 is positioned on the upper part of a telescopic gas collecting cavity 19 and is communicated with the telescopic gas collecting cavity 19. In this embodiment, the position of the rubber stopper 8 in the sampling tube 17 is above the sampling tube switch 16, i.e. away from the retractable gas collecting chamber 19.

The air extractor consists of an air extracting pipe 13, an air extracting pipe branch pipe 25, a one-way valve A11, a liquid evaporation cavity air extracting switch 12, a one-way valve C20, a telescopic air collecting cavity air extracting switch 21 and an air extracting pump 22.

One end of the exhaust tube 13 is communicated with the liquid evaporation cavity 10, the other end is communicated with the air pump 22, one end of the exhaust tube branch tube 25 is communicated with the exhaust tube 13, and the other end is communicated with the telescopic gas collecting cavity 19. The one-way valve A11 and the liquid evaporation cavity air extraction switch 12 are respectively arranged at the communication part of the air extraction pipe 13 and the liquid evaporation cavity 10, and the one-way valve C20 and the telescopic gas collection cavity air extraction switch 21 are respectively arranged at the communication part of the air extraction pipe 13 and the telescopic gas collection cavity 19.

In this embodiment, the air exhaust pipe 13 and the air exhaust pipe branch pipe 25 are both 304 stainless steel pipes with an inner diameter of 2mm and an outer diameter of 3mm, the sampling pipe switch 7, the liquid evaporation cavity air exhaust switch 12 and the telescopic air collection cavity air exhaust switch 21 are all 316 two-way ball valves, the check valve a11, the check valve B15 and the check valve C20 are all 316 split internal thread check valves, and the air exhaust pump 22 is a dar Tuo VP1500 mute oil-free vacuum pump.

When the liquid evaporation cavity 10 and the telescopic gas collecting cavity 19 are sealed and closed, the sampling tube 9 and the sampling tube 17 are respectively controlled by the sampling tube switch 7, the rubber plug 8 in the sampling tube 9, the sampling port switch 16 and the rubber plug 8 in the sampling tube 17, so as to ensure the sealing property. When sampling, a special liquid sample injection needle is adopted to penetrate through the rubber plug 8 for sampling, and when sampling, a dead volume-free gas sampler is adopted to penetrate through the rubber plug 8 for sampling.

The specific operation process for evaporating the trace high-purity liquid sample by using the method disclosed by the invention is as follows:

1. stage of extracting impurity gas

Firstly, closing the sampling pipe switch 7, the sampling pipe switch 16 and the steam extraction switch 14, then opening the liquid evaporation cavity air extraction switch 12 and the telescopic gas collection cavity air extraction switch 21, and then opening the air extraction pump 22 to extract impurity gas, namely, the phase of extracting impurity gas begins.

Observing the state in the device, when the piston 1 falls to the lowest position and does not fall any more, and the retractable gas collecting chamber 19 retracts to the minimum and does not retract any more, it can be considered that the extraction of the impurity gas is completed. The liquid evaporation cavity air extraction switch 12 and the telescopic gas collection cavity air extraction switch 21 are closed, then the air extraction pump 22 is closed, and the stage of extracting the impurity gas is ended.

2. Liquid sample introduction

Firstly, a sample inlet pipe switch 7 is opened, a liquid sample needle penetrates through a rubber plug 8 in a sample inlet pipe 9 to inject a liquid sample into a liquid evaporation cavity 10, and then the sample inlet pipe switch 7 is closed to finish the injection of the liquid sample.

3. Evaporation of liquid sample

After the temperature in the main body 24 is adjusted to a suitable evaporation temperature by adjusting the heating belt temperature controller 5, the liquid sample starts to evaporate. When the piston 1 is observed to rise slowly and maintain a certain height without changing any more, the evaporation of the liquid sample is finished.

4. Gas sample collection

The steam extraction switch 14 is opened and then slowly depressed to move the piston 1 downwards, while the telescopic gas collection chamber 19 is observed to slowly expand as the piston 1 descends. When the piston 1 is depressed to the bottom and can not be depressed any more, the vapor extraction switch 14 is closed, and the gas sample collection process is completed.

5. Gas sample sampling

The sampling tube switch 16 is opened and the sampling needle is inserted through the rubber stopper 8 in the sampling tube 17 to extract the desired gas sample. After sampling, the sampling needle is pulled out, the sampling tube switch 16 is closed, and the gas sample sampling is finished at the moment.