Pore water sampler suitable for sediments

Abstract

The pore water sampler comprises a Luer taper connected with a negative pressure or collecting device, the other end of the Luer taper is connected with an extension pipe, the other end of the extension pipe is connected with a sampling head, the sampling head is connected with the extension pipe through a connecting sleeve, and the connecting sleeve is connected with the connecting sleeve. The sediment pore water sampling device is simple in structure, when the sediment pore water sampling device is used, sediment pore water is filtered from the hydrophilic porous membrane through negative pressure or collecting equipment and enters the pipe from the outside of the hydrophilic porous membrane, and by means of the sampling head with the hydrophilic porous membrane, the sampling efficiency of the sediment pore water is improved; the defect that a single-hole membrane is easy to block is effectively overcome, the obtained solution is pollution-free, and the instrument is easy to operate.

Description

Technical Field

[0001] The invention relates to the technical field of environmental science, and in particular to a pore water sampler suitable for sediments. Background Art

[0002] Seabed sediments, riverbed sediments, lake sediments, swamps, wetlands and soils are often porous media systems composed of particles such as sand, clay, silt, peat, chalk and loam, as well as pore water between particles. Pore water contains a large amount of geochemical information, such as dissolved organic carbon and inorganic carbon, nutrients, metal ions, pH, etc. The content and distribution of these dissolved components are the basis for the study of geochemistry and geological effects in sediments, soil nutrition and pollution, and lake eutrophication.

[0003] Analysis of pore water chemistry depends on the ability to separate water from solids while minimizing changes to its chemical properties during the extraction process. Traditional methods for extracting sediment pore water include centrifugation, pressing, and vacuum extraction, each of which has its own shortcomings. For example, centrifugation allows for fairly high sampling resolution (<1 cm) and can extract large amounts of pore water from cohesive sediments. The use of centrifuges during ocean research cruises is often impractical due to the difficulty in balancing centrifuges, so high-pressure extrusion is often used for pore water extraction in ocean drilling programs. However, extrusion is a cumbersome process that does not allow for high-resolution sampling and may damage sediment samples. For another example, the traditional method of sampling soil solution is to directly excavate the soil profile to obtain soil samples, and then separate the soil solution by extrusion or centrifugation. This method severely damages the soil structure. During the excavation process, the integrity of the soil pores is destroyed, causing the soil solution to be lost and redistributed during the excavation process, resulting in the obtained solution sample not accurately reflecting the true situation of the soil solution in its natural state. In summary, the traditional pore water sampling method is cumbersome and inefficient, especially when a large number of samples are required or the timeliness of the samples is high, it cannot meet the needs.

[0004] Although some early sediment pore water samplers on the market have improved the problems of traditional methods to a certain extent, they still have many shortcomings, mainly including: 1. The material selection of some samplers is improper, which will react chemically with pore water, thereby affecting the composition of the solution. For example, some metal samplers will corrode and release metal ions into the solution when in contact with acidic or alkaline soil solutions, contaminating the sample and causing deviations in the analysis results. 2. The size of the pore water sampling head is too large, which can easily destroy the medium structure of the sediment or soil during sampling, thereby causing disturbance of pore water in the sediment. 3. The material of the microporous membrane is not completely inert, and there is ion exchange, adsorption of dissolved organic or inorganic matter, isotope fractionation or selective adsorption of heavy metals. 4. The hydrophilicity of the microporous membrane is poor, the flux is small, the permeability is poor, and the sampling process takes too long, resulting in the overflow of carbon dioxide and methane gas from the pore water during sampling. 5. There is no support column, which makes the sampler easy to bend or break when inserted and pulled out of the sediment or soil.

[0005] Therefore, a pore water sampler for sediments needs to be studied urgently. Summary of the invention

[0006] The purpose of the present invention is to provide a pore water sampler suitable for sediments, which increases the sampling efficiency of sediment pore water by using a sampling head with a hydrophilic porous membrane, and effectively solves the disadvantage that the single-pore membrane is easily blocked; and the structure is simple, the solution obtained is pollution-free, and the device is easy to operate.

[0007] In order to solve the above technical problems, the present invention solves the problems through the following technical solutions: a pore water sampler suitable for sediments, comprising a Luer connector connected to a negative pressure or collection device, the other end of the Luer connector is connected to an extension tube, the other end of the extension tube is connected to a sampling head, the sampling head and the extension tube are connected by a connecting sleeve, and a plurality of filtering holes are opened at one end of the sampling head.

[0008] Preferably, the sampling head comprises a connecting tube connected to the connecting sleeve and a head body, and the head body is made of a hydrophilic porous membrane.

[0009] Further preferably, the sampling head and the extension tube are connected via a support tube.

[0010] Further preferably, the head body is a conical tip structure, a flat structure or a round head structure.

[0011] Further preferably, the diameter of the head body is 1-10 mm, and the pore size of the filter hole is 0.1-0.8 um.

[0012] Further preferably, the connecting tube and the connecting sleeve are connected by light curing or cyclohexanone bonding, and the Luer connector and the extension tube are bonded by cyclohexanone.

[0013] Further preferably, the support tube has a diameter of 0.5-1.5 mm.

[0014] Further preferably, the Luer connector comprises a Luer male connector and a Luer female connector, one end of the Luer female connector is connected to a syringe, and one end of the syringe is provided with a negative pressure plate.

[0015] Further preferably, the sampling head outer cover is provided with a protection mechanism, the protection mechanism includes a protective sleeve, the protective sleeve is provided with a connecting ring at one end corresponding to the connecting sleeve, the inner wall of the connecting ring is provided with an internal thread, the connecting sleeve is provided with an external thread threadedly connected to the connecting ring, the other end of the protective sleeve is provided with a liquid inlet hole, and the protective sleeve is provided with an obstacle clearing device.

[0016] Further preferably, the obstacle clearing device comprises two groups of cross-hinged arc-shaped brackets, an upper support rod and a lower support rod are respectively provided at the upper and lower ends of the arc-shaped bracket, a pressing control ring is provided in the middle of the connecting ring, a spring is provided between the upper support rod and the pressing control ring, an arc-shaped support plate is provided at the lower end of the lower support rod, a through groove is opened at the lower end of the protective cover, and a obstacle clearing plate which can be retracted and extended in the through groove is connected to the lower end of the arc-shaped support plate.

[0017] The beneficial effects of the present invention include: comprising a Luer connector connected to a negative pressure or collection device, the other end of the Luer connector is connected to an extension tube, the other end of the extension tube is connected to a sampling head, the sampling head and the extension tube are connected by a connecting sleeve, and a plurality of filtering holes are provided at one end of the sampling head. The present invention has a simple structure. When in use, the pore water of the sediment is filtered from the hydrophilic porous membrane by the negative pressure or collection device, and enters the tube from the outside of the hydrophilic porous membrane. By using the sampling head of the hydrophilic porous membrane, the sampling efficiency of the pore water is increased, and the disadvantage that the single-pore membrane is easily blocked is effectively solved. The obtained pore water is pollution-free and the instrument is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural diagram of embodiment 1 of the present invention.

[0019] Figure 2 It is a schematic structural diagram of a flat sampling head according to an embodiment of the present invention.

[0020] Figure 3 It is a schematic structural diagram of a conical tip sampling head according to an embodiment of the present invention.

[0021] Figure 4 It is a structural schematic diagram of a circular sampling head according to an embodiment of the present invention.

[0022] Figure 5 This is a usage status diagram of the first embodiment of the present invention.

[0023] Figure 6 It is a structural diagram of embodiment 2 of the present invention.

[0024] Figure 7 It is a schematic diagram of the decomposed structure of the second embodiment of the present invention. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0026] Embodiment 1, as Figure 1-5 As shown, a pore water sampler suitable for sediment comprises a Luer connector 1 connected to a negative pressure or collection device, the Luer connector 1 comprises a Luer male connector and a Luer female connector, one end of the Luer female connector is connected to a syringe 6, one end of the syringe 6 is provided with a negative pressure plate 7, the other end of the Luer connector 1 is connected to an extension tube 2, the other end of the extension tube 2 is connected to a sampling head 3, the sampling head 3 is connected to the extension tube 2 through a connecting sleeve 4, one end of the sampling head 3 is provided with a plurality of filtering holes, the structure of the present invention is simple, when in use, the pore water of the sediment is filtered from the hydrophilic porous membrane by the negative pressure or collection device , entering the tube from the outside of the hydrophilic porous membrane. By using the sampling head 3 of the hydrophilic porous membrane, the sampling efficiency of the sediment pore water is increased, and the disadvantage that the single-pore membrane is easily blocked is effectively solved. The obtained solution is pollution-free and the instrument is easy to operate. It is suitable for analyzing various components dissolved in sediment or soil pore water. The whole set of instruments has no metal structure, and the overall instrument cavity is less than 1ml; as much collected solution as possible is allowed to enter the collection device without being wasted in the instrument lumen. Moreover, they are all inert materials, without ion exchange, and will not adsorb dissolved organic or inorganic matter. The sampling results are accurate, and it is convenient for frequent sampling after installation, and can be discarded after use.

[0027] In this embodiment, the sampling head 3 includes a connecting tube 31 connected to the connecting sleeve 4 and a head body 32. The head body 32 is made of a hydrophilic porous membrane. The head body 32 adopts a structure that does not damage sediments, soil or other solid media. The head body 32 is a conical tip structure (micro-tip), a flat structure or a round head structure, etc., which is easy to insert into the seabed mud and seabed sand, and can realize seabed area sampling. The diameter of the head body 32 is 1-10mm. When used for soil pore water sampling, a coarse sampling can be used according to actual needs. The sampling head is used to increase the sampling speed. The pore size of the filter hole is 0.1-0.8um. ​​The overall size is small and easy to insert into the seabed sediment. The hydrophilic porous membrane has the characteristics of high flow rate and low dissolution. It does not adsorb proteins and extracts, has no pollution to the sample, has excellent chemical stability, and can resist corrosion from a variety of chemical substances, such as acids, alkalis, organic solvents, etc. The hydrophilic porous membrane material specifically includes but is not limited to cellulose esters, polyamides, polysulfones (PES), etc. After the head body 32 is wetted, only the solution can penetrate.

[0028] In this embodiment, the sampling head 3 and the extension tube 2 are connected by a support tube 5, and the diameter of the support tube 5 is 0.5-1.5 mm. The support tube 5 can increase the support strength of the sampling head 3, and is easy to insert into the seabed soil to prevent bending. The support tube 5 includes but is not limited to glass fiber, carbon fiber, nylon, polyetheretherketone and other materials that do not affect the sampling results, and can provide strong supporting force.

[0029] In this embodiment, the connecting tube 31 and the connecting sleeve 4 are connected by light curing or cyclohexanone bonding, and the Luer connector 1 and the extension tube 2 are bonded by cyclohexanone.

[0030] Embodiment 2, as Figure 6 , 7 The sampling head 3 is provided with a protective mechanism 8, and the protective mechanism 8 includes a protective sleeve 81. The protective sleeve 81 is provided with a connecting ring 82 at one end corresponding to the connecting sleeve. The inner wall of the connecting ring 82 is provided with an internal thread, and the connecting sleeve is provided with an external thread screwed with the connecting ring 82. The other end of the protective sleeve 81 is provided with a liquid inlet 83, and the protective sleeve 81 is provided with an obstacle clearing device, and the protective mechanism 8 is fixed to the connecting sleeve by a threaded form; the main function is: the permeability of the inorganic ceramic membrane currently used is too low to meet the sampling requirements of pore water in seabed sediments; we use a porous fiber membrane with a high permeability rate, but the porous fiber membrane is not hard enough, so a support column is used, and sufficient space is reserved between the fiber membrane and the support column; this can meet the requirements of high permeability and hardness at the same time; and on this basis, the protective mechanism 8 is added to further prevent the risk of breaking the sampling head.

[0031] In this embodiment, the obstacle removal device includes two groups of cross-hinged arc brackets 84, the upper and lower ends of the arc bracket 84 are respectively provided with an upper support rod 85 and a lower support rod, the middle part of the connecting ring 82 is provided with a pressing control ring 87, a spring 88 is provided between the upper support rod 85 and the pressing control ring 87, the lower end of the lower support rod is provided with an arc support plate 86, the lower end of the protective cover 81 is provided with a through groove, the lower end of the arc support plate 86 is connected to an obstacle removal plate 89 that can be retracted in the through groove, and the obstacle removal plate 89 is provided with obstacle removal teeth. When the sampling operation of the pore water of the seabed sediment is performed, when the head body 32 of the sampling head 3 encounters the sampling area When the sampling head 3 is small and there are hard substances, in order to avoid damaging the head body 32 of the sampling head 3, the protective mechanism 8 will be inserted into the seabed sediment first, and then the pressing control ring 87 will be pressed to drive the upper support rod 85 to push the two sets of cross-hinged arc brackets 84 to telescope and rotate, and push the lower support rod and the arc support plate 86 to move downward, and at the same time, the obstacle plate 89 will be pushed out from the through groove, and then the protective mechanism 8 will be spirally rotated as a whole, and the obstacle materials will be cleared out of the sampling area of ​​the head body 32 through the obstacle plate 89. Finally, the pore water of the seabed sediment will pass through the liquid inlet hole 83 through negative pressure or collection equipment, and then enter the filter hole of the head body 32 for filtration, and finally enter the tube from the outside of the hydrophilic porous membrane.

[0032] According to the concept of the present invention, there may be changes in the specific implementation method and application scope, and the content of this specification should not be understood as limiting the present invention.

Claims

1. A pore water sampler suitable for sediments, characterized in that: It comprises a Luer connector connected to a negative pressure or collection device, the other end of the Luer connector is connected to an extension tube, the other end of the extension tube is connected to a sampling head, the sampling head and the extension tube are connected via a connecting sleeve, and one end of the sampling head is provided with a plurality of filtering holes.

2. A pore water sampler suitable for sediments according to claim 1, characterized in that: The sampling head comprises a connecting tube connected to a connecting sleeve and a head body, and the head body is formed by a hydrophilic porous membrane.

3. A pore water sampler suitable for sediments according to claim 1, characterized in that: The sampling head and the extension tube are connected through a supporting tube.

4. A pore water sampler suitable for sediments according to claim 2, characterized in that: The head body is a conical tip structure, a flat structure or a round head structure.

5. A pore water sampler suitable for sediments according to claim 2, characterized in that: The diameter of the head body is 1-10 mm, and the aperture of the filter hole is 0.1-0.8 um.

6. A pore water sampler suitable for sediments according to claim 2, characterized in that: The connecting tube and the connecting sleeve are connected by light curing or cyclohexanone bonding, and the Luer connector and the extension tube are bonded by cyclohexanone.

7. A pore water sampler suitable for sediments according to claim 3, characterized in that: The support tube has a diameter of 0.5-1.5 mm.

8. A pore water sampler suitable for sediments according to claim 1, characterized in that: The Luer connector comprises a Luer male connector and a Luer female connector. One end of the Luer female connector is connected to a syringe, and one end of the syringe is provided with a negative pressure plate.

9. A pore water sampler suitable for sediments according to claim 1, characterized in that: The sampling head outer cover is provided with a protection mechanism, which includes a protective sleeve, and the protective sleeve is provided with a connecting ring at one end corresponding to the connecting sleeve, the inner wall of the connecting ring is provided with an internal thread, the connecting sleeve is provided with an external thread threaded with the connecting ring, the other end of the protective sleeve is provided with a liquid inlet hole, and the protective sleeve is provided with an obstacle clearing device.

10. A pore water sampler suitable for sediments according to claim 9, characterized in that: The obstacle clearing device includes two groups of cross-hinged arc-shaped brackets, an upper support rod and a lower support rod are respectively provided at the upper and lower ends of the arc-shaped bracket, a pressing control ring is provided in the middle of the connecting ring, a spring is provided between the upper support rod and the pressing control ring, an arc-shaped support plate is provided at the lower end of the lower support rod, a through groove is opened at the lower end of the protective cover, and an obstacle clearing plate which can be retracted and extended in the through groove is connected to the lower end of the arc-shaped support plate.

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