CN-122016395-A - DGT passive sampling device and method for detecting drinking groundwater

CN122016395ACN 122016395 ACN122016395 ACN 122016395ACN-122016395-A

Abstract

The invention discloses a DGT passive sampling device and a DGT passive sampling method for detecting drinking groundwater, wherein the device comprises a bearing supporting mechanism and a plurality of passive samplers arranged on the bearing supporting mechanism, the bearing supporting mechanism comprises a bearing supporting column body, a plurality of sampler mounting holes are formed in the side face of the bearing supporting column body, the passive samplers comprise sampler supporting outer cylinder shells which are arranged in the sampler mounting holes and are coaxially arranged with the sampler mounting holes, a membrane group mounting cylinder shell with an opening at one end is slidably arranged in the sampler supporting outer cylinder shell, a composite gradient diffusion membrane group is fixed in the membrane group mounting cylinder shell, and the device is provided with integrated accurate collection of multiple types of pollutants, so that the data representativeness and accuracy are improved.

Inventors

ZHU LIN
SU QIUKE
RUI HANYI
Zhu qinyuan
SUN ZHIYONG
YU QIAO
MA HUI

Assignees

生态环境部南京环境科学研究所
新疆生产建设兵团第十二师生态环境监测站

Dates

Publication Date: 20260512
Application Date: 20260211

Claims (7)

1. The DGT passive sampling device for detecting drinking groundwater is characterized by comprising a bearing and supporting mechanism (10) and a plurality of passive samplers (20) arranged on the bearing and supporting mechanism (10); The bearing and supporting mechanism (10) comprises a bearing and supporting column body (11), and a plurality of sampler mounting holes (110) extending along the radial direction of the bearing and supporting column body (11) are formed in the side surface of the bearing and supporting column body; The passive sampler (20) comprises a sampler supporting outer cylinder shell (21) which is arranged in the sampler mounting hole (110) and is coaxially arranged with the sampler supporting outer cylinder shell, a membrane group mounting cylinder shell (22) with an opening at one end is slidably arranged in the sampler supporting outer cylinder shell (21), and a composite gradient diffusion membrane group (23) is fixed in the membrane group mounting cylinder shell (22); The top of the bearing support column (11) is fixedly provided with a cable installation hanging ring (101).
2. The DGT passive sampling device for potable groundwater detection according to claim 1, wherein the composite gradient diffusion membrane set (23) comprises a protective membrane (231), an anion selective diffusion membrane (232), an anion targeting adsorption membrane (233), a cation selective diffusion membrane (234), a cation targeting adsorption membrane (235), a neutral organic selective diffusion membrane (236) and a neutral organic targeting adsorption membrane (237) connected in sequence; when the composite gradient diffusion membrane group (23) is installed in the membrane group installation cylinder shell (22), the neutral organic targeting adsorption membrane (237) is close to the inner end part of the membrane group installation cylinder shell (22), and the protection membrane (231) is flush with the opening end of the membrane group installation cylinder shell (22); The diameters of the anion selective diffusion membrane (232), the anion targeted adsorption membrane (233), the cation selective diffusion membrane (234), the cation targeted adsorption membrane (235), the neutral organic selective diffusion membrane (236) and the neutral organic targeted adsorption membrane (237) are consistent with the inner diameter of the membrane group installation cartridge (22), and the diameter of the protection membrane (231) is consistent with the outer diameter of the membrane group installation cartridge (22).
3. The DGT passive sampling device for detecting drinking groundwater according to claim 1, wherein one end of the sampler supporting outer cylinder shell (21) close to the opening of the membrane group installing cylinder shell (22) is a water inlet end, the water inlet end of the sampler supporting outer cylinder shell (21) is provided with a pretreatment anti-blocking mechanism (30), the pretreatment anti-blocking mechanism (30) comprises an anti-blocking supporting pipe shell (31) which is slidably connected in the sampler supporting outer cylinder shell (21), a plurality of sealing ring grooves (311) are arranged on the outer side surface of the anti-blocking supporting pipe shell (31), a rubber sealing ring (312) is fixed in the sealing ring grooves (311), and the rubber sealing ring (312) is in pressing sealing fit with the inner side wall of the sampler supporting outer cylinder shell (21); One end of the anti-blocking support tube shell (31) positioned in the sampler support outer tube shell (21) is in contact fit with the top of the opening end of the membrane group installation tube shell (22); The water inlet end of the sampler supporting outer cylinder shell (21) is in threaded connection with a sealing clamping end cover (32), a through hole (321) penetrating along the axis of the sampler supporting outer cylinder shell (21) is formed in the sealing clamping end cover (32), a clamping fit ring (313) is fixed on the outer side of the anti-blocking supporting tube shell (31), and the clamping fit ring (313) is in contact fit with the top of the inner end surface of the sealing clamping end cover (32); One end of the anti-blocking support tube shell (31) far away from the membrane group installation tube shell (22) extends out of the perforation (321); One end of the anti-blocking support tube shell (31) far away from the membrane group installation tube shell (22) is provided with a blocking filter support ring (33), and a hemispherical ceramic hemispherical filter shell (331) is fixed on one side of the blocking filter support ring (33) far away from the anti-blocking support tube shell (31); The anti-blocking support tube shell (31) is far away from a plurality of magnetic attraction connecting holes (332) are formed in the end face of the membrane group installation tube shell (22), a fastening magnetic attraction permanent magnet (333) is fixed in the inner bottom of each magnetic attraction connecting hole (332), a plurality of magnetic attraction connecting columns (334) are fixed on one side, close to the anti-blocking support tube shell (31), of each blocking support ring (33), and the magnetic attraction connecting columns (334) are in one-to-one sliding connection in each magnetic attraction connecting hole (332).
4. The DGT passive sampling device for potable groundwater detection according to claim 1, characterized in that one end of the sampler support outer casing (21) far from the opening of the membrane group installation casing (22) is a closed end, the closed end of the sampler support outer casing (21) is provided with a pressure-resistant sealing mechanism (40), the pressure-resistant sealing mechanism (40) comprises a pressure-resistant sealing end cover (41) fixedly connected to the closed end of the sampler support outer casing (21) through threads, a limit support casing (42) coaxially arranged with the sampler support outer casing (21) is fixed on the inner side of the pressure-resistant sealing end cover (41), a limit support column (43) coaxially arranged with the sampler support outer casing (21) is fixed on the closed end of the membrane group installation casing (22), and the limit support column (43) is slidably connected in the limit support casing (42); and a limit support spring (431) is arranged between the limit support column (43) and the inner end part of the limit support cylinder shell (42) in a jacking fit manner.
5. A DGT passive sampling device for potable groundwater detection according to claim 1, characterized in that the sampler support outer cartridge housing (21) is connected in the sampler mounting hole (110) by a quick release mechanism (50), the quick release mechanism (50) comprising a quick release support ring (51) fixed in the sampler mounting hole (110), the sampler support outer cartridge housing (21) being slidingly connected in the quick release support ring (51); the sampler supports outer shell (21) outside and is fixed with a plurality of quick detach supporting shoe (52), every quick detach supporting shoe (52) side all is fixed with two and winds sampler supports outer shell (21) circumference extension's quick detach restraint splint (53), every two on quick detach supporting shoe (52) quick detach restraint splint (53) are a set of, every group quick detach restraint splint (53) one side that is close to each other is equipped with along sampler supports outer shell (21) radial extension's quick detach restraint recess (531), be fixed with many quick detach restraint spliced pole (54) along its radial extension on sampler mounting hole (110) inside wall, many quick detach restraint spliced pole (54) one-to-one joint is in each group quick detach restraint recess (531).
6. The DGT passive sampling device for potable groundwater detection according to claim 1, wherein a distributed monitoring mechanism (60) is arranged outside the sampler support outer cylinder housing (21), the distributed monitoring mechanism (60) comprises a plurality of distributed monitoring support columns (61) fixed outside the sampler support outer cylinder housing (21), one end of each distributed monitoring support column (61) away from the sampler support outer cylinder housing (21) is provided with a monitoring accommodation hole (610), a water environment monitoring sensor (62) is arranged in each monitoring accommodation hole (610), and a monitoring protection filter screen (611) is fixed at an opening of each monitoring accommodation hole (610).
7. A DGT passive sampling method for potable groundwater detection, based on the DGT passive sampling device for potable groundwater detection according to any one of claims 1 to 6, characterized by comprising the steps of: s1, drilling a sampling well: drilling a sampling well communicated with the underground water to be detected by using drilling equipment; S2, assembling a sampling device: Firstly, a composite gradient diffusion membrane group (23) is arranged in a membrane group installation cylinder shell (22), then the membrane group installation cylinder shell (22) is arranged in a sampler support outer cylinder shell (21), and finally the sampler support outer cylinder shell (21) is arranged in a sampler installation hole (110) and the opening of the membrane group installation cylinder shell (22) is outwards arranged; S3, arranging a sampling device in a well: one end of a cable is fixed on a cable mounting hanging ring (101), a mounted bearing support column (11) is placed in a sampling well, the bearing support column (11) is gradually sent into the sampling well under the traction and release of the cable until the whole bearing support column (11) is immersed in groundwater, and finally the other end of the cable is fixed on the ground; S4, passive sampling waiting: the whole bearing and supporting column body (11) is continuously immersed in underground water for 7-28 days; S5, recycling by a sampling device: After the immersion time expires, the whole bearing support column body (11) is taken out of the sampling well through cable traction, the sampler support outer cylinder shell (21) is detached from the sampler mounting hole (110), the membrane group mounting cylinder shell (22) is detached from the sampler support outer cylinder shell (21), and finally the composite gradient diffusion membrane group (23) is taken out of the membrane group mounting cylinder shell (22), and the composite gradient diffusion membrane group (23) is filled into a clean storage box and is brought back to a detection laboratory.

Description

DGT passive sampling device and method for detecting drinking groundwater Technical Field The invention relates to the technical field of water pollution detection, in particular to a DGT passive sampling device and a DGT passive sampling method for detecting drinking groundwater. Background Novel pollutants (ECs) are a class of pollutants of great interest in recent years, which are pollutants that are already present in the environment, but are not yet subject to relevant regulatory restrictions and may be harmful to the human and ecological environment. The national institute of government issued "new pollutant treatment action scheme" on day 4 and 5 of 2022, which improves the research and control of new pollutants to a new height. The development of related research on novel pollutants is an important strategic task and is also a great demand for improving environmental quality and realizing sustainable development in the future. Groundwater is the most reliable perennial fresh water resource on earth, which maintains the flow and water level of rivers and lakes, and is critical to the health of ecosystems and people, especially in Xinjiang areas of arid. Due to the influence of industrial and agricultural activities, a large amount of new pollutants are discharged into the underground water, and the quality and agricultural safety of the underground water are endangered. And the underground water pollution has the characteristics of concealment, long-term property, difficult recovery and the like. The research on whether new pollutants exist in drinking water (underground water) and how does the pollution characteristics and risks of the new pollutants have important scientific significance, not only providing data support and technical support for monitoring the new pollutants in the underground water, providing scientific basis for the next step of underground water condition detail and centralized pollution control management work of drinking water sources, but also providing data, technical support and reserve for developing the control of the new pollutants, and even providing important scientific support for regional ecological environment and promoting high-quality development. Disclosure of Invention The invention aims to provide a DGT passive sampling device and a DGT passive sampling method for detecting drinking groundwater, which have the integrated and accurate collection function of multiple types of pollutants. In order to achieve the above purpose, the present invention provides the following technical solutions: the DGT passive sampling device for detecting the drinking groundwater comprises a bearing and supporting mechanism and a plurality of passive samplers arranged on the bearing and supporting mechanism; the bearing support mechanism comprises a bearing support column body, and the side surface of the bearing support column body is provided with a plurality of sampler mounting holes extending along the radial direction of the bearing support column body; the passive sampler comprises a sampler support outer cylinder shell which is arranged in a sampler mounting hole and is coaxially arranged with the sampler support outer cylinder shell, a membrane group mounting cylinder shell with one end open is slidably arranged in the sampler support outer cylinder shell, and a composite gradient diffusion membrane group is fixed in the membrane group mounting cylinder shell; the top of the bearing support column body is fixed with a cable mounting hanging ring. Preferably, the composite gradient diffusion film group comprises a protective film, an anion selective diffusion film, an anion targeting adsorption film, a cation selective diffusion film, a cation targeting adsorption film, a neutral organic selective diffusion film and a neutral organic targeting adsorption film which are sequentially connected; When the composite gradient diffusion membrane group is installed in the membrane group installation cylinder shell, the neutral organic targeting adsorption membrane is close to the inner end part of the membrane group installation cylinder shell, and the protective membrane is flush with the opening end of the membrane group installation cylinder shell; the diameters of the anion selective diffusion membrane, the anion targeted adsorption membrane, the cation selective diffusion membrane, the cation targeted adsorption membrane, the neutral organic selective diffusion membrane and the neutral organic targeted adsorption membrane are consistent with the inner diameter of the membrane group installation cylinder shell, and the diameter of the protection membrane is consistent with the outer diameter of the membrane group installation cylinder shell. The composite gradient diffusion membrane group can realize the targeted diffusion and adsorption of anions, cations and neutral organic pollutants in the groundwater at the same time, and the sampling of key pollutants in the groundwater can