CN110907225B

CN110907225B - Underground water high-fidelity sampling system and sampling method

Info

Publication number: CN110907225B
Application number: CN201911009473.7A
Authority: CN
Inventors: 温吉利; 刘向国
Original assignee: Beijing Research Institute of Chemical Engineering and Metallurgy of CNNC
Current assignee: Beijing Research Institute of Chemical Engineering and Metallurgy of CNNC
Priority date: 2019-10-23
Filing date: 2019-10-23
Publication date: 2022-03-04
Anticipated expiration: 2039-10-23
Also published as: CN110907225A

Abstract

The invention provides a groundwater high-fidelity sampling system and a sampling method, wherein the groundwater high-fidelity sampling system is characterized in that a near liquid surface deep well sampling device for sucking groundwater is arranged under the liquid surface in a well pipe, and a water outlet pipe arranged at the top of the near liquid surface deep well sampling device is sequentially communicated with a quality stabilizer, a laminar flow sampler and a sampling bottle which are arranged on the ground. In the underground water high-fidelity sampling system, in the sampling process, a water sample falls into the sampling bottle from the mesh pipe at the lower end of the liquid-facing deep well sampling device and finally flows into the sampling bottle, and the flow rate of water pumping is controlled by adjusting the flow regulator, so that the sampled water flow is stable, micro-disturbance water pumping is realized, the overflow probability of volatile substances in water can be effectively reduced, and the fidelity of the water sample is improved. The sampling device for the liquid-facing deep well placed in water has a simple structure and low energy consumption, and can solve the problems of high energy consumption, limited depth of a sampling point and the like of conventional sampling equipment.

Description

Underground water high-fidelity sampling system and sampling method

Technical Field

The invention relates to a sampling system for sampling underground water, in particular to an underground water high-fidelity sampling system and a sampling method.

Background

The basic principle of the method is that holes are drilled in an ore-containing layer capable of being subjected to ground leaching according to a certain mesh degree arrangement process, leaching solution is injected into the ore-containing layer from a liquid injection hole, the leaching solution mainly reacts with target minerals in the ore-containing layer and is dissolved to form leaching solution, the leaching solution is extracted to the ground surface through a liquid extraction hole, after the target minerals are extracted in a ground surface factory, leaching agent is supplemented into discharged tail solution to form the leaching solution, and then the leaching solution is injected into the ore-containing layer again through the liquid injection hole to perform a circulating mining process. In order to prevent pollution of the underground water environment around the well site caused by the ground leaching mining process and protect the underground water environment, the well site boundary needs to be monitored. Monitoring wells with the inner diameter of 0.08-0.1 m are usually arranged on the periphery of a well site and an upper aquifer and a lower aquifer which are adjacent to each other and are used for periodically sampling and sending to a laboratory for detection.

At present, most of uranium leaching mines directly sample underground water at a filter position of a monitoring well by adopting a one-way valve Beller sampler, and the quality and the environment of a sample are easily influenced by adopting the Beller sampler to sample water: firstly, a backwater dead angle exists at the water inlet end of the Beller sampler, the submergence rate of the Beller sampler in well water is difficult to control, so that the well water continuously entering the upper section of a monitoring well of the sampler cannot be completely discharged out of the sampler, and the water sample collected at the planned depth is distorted; secondly, when the sampler submerges in the well, part of substances in water at the upper section of the well can be adhered to the surface of the sampler, so that the quality of a water sample is influenced; thirdly, due to the influence of the sampler structure, the sampler is not easy to clean, cross contamination among samples is easy to cause, and the cleaning water can also generate secondary pollution to the environment.

Disclosure of Invention

The invention aims to provide a high-fidelity underground water sampling system, which solves the problems that water samples collected in a deepwater well by adopting the existing sampling technology are easy to distort and cross contamination among the samples is easy to cause.

The invention also aims to provide a high-fidelity underground water sampling method to realize high-fidelity acquisition of water samples containing environment sensitive substances in deep wells.

One of the objects of the invention is achieved by: a groundwater high fidelity sampling system comprising:

the near-liquid-level deep well sampling device is used for pumping underground water in an aquifer corresponding to the filter in the deep well, the pumping equipment is arranged below the liquid level in the deep well and close to the liquid level, and a water inlet port of the pumping equipment is submerged to the position of the filter in the deep well through a connecting pipeline;

the quality stabilizer is connected to a water outlet pipeline of the liquid level facing deep well sampling device and is used for stabilizing the collected water sample and redissolving volatile and semi-volatile substances separated out from the water sample;

the laminar flow sampler is connected to a water outlet pipeline behind the quality stabilizer and used for adjusting the water pressure and flow of the collected water sample and improving the fidelity of the water sample; and

the sampling bottle is used for collecting the collected water sample output by the laminar flow sampler.

Face liquid level deep water well sampling device includes:

the submersible pump is a cylindrical pump body, a water outlet pipe used for guiding the water to the ground is connected to a water outlet at the top of the submersible pump, scale marks representing the length of the water outlet pipe are marked on the pipe wall of the water outlet pipe, and one end of the starting point of the scale marks of the water outlet pipe of the marking column is connected to the water outlet of the submersible pump;

the upper part of the fluid guide body is a cylindrical pipe body with the same diameter as the submersible pump, the lower part of the fluid guide body is a cone with a downward tip part, and the fluid guide body is arranged at the lower end of the submersible pump to ensure that the water flow in the sampling system changes smoothly;

the drainage cover is a cover body which covers the periphery of the submersible pump and the drainage fluid, the cover body comprises a large-diameter section positioned at the upper part, a small-diameter section positioned at the lower part and a reducing section for connecting the large-diameter section and the small-diameter section, the upper end opening of the large-diameter section is sealed on a pump body at the upper part of a water inlet annular opening of the submersible pump, the reducing section corresponds to a lower cone of the drainage fluid, the taper of the reducing section is consistent with that of the lower cone of the drainage fluid, the diameter of the small-diameter section is larger than that of the water outlet pipe, and the sectional area of an annular cavity formed between the large-diameter section and the drainage fluid is not larger than that of the small-diameter section;

the upper end of the water inlet pipe is connected to the small-diameter section of the drainage cover, and the lower end of the water inlet pipe is connected with the perforated net pipe pendant; and

the mesh pipe drop is arranged at a filter at the lower part of the deep well and used for collecting underground water and providing pull-down gravity for keeping the water inlet pipe in a straight state; the structure is that the bottom of a section of straight-wall lattice net pipe is connected with a conical bottom plate, the top of the straight-wall lattice net pipe is connected with an annular top plate, and the inner circle of the annular top plate is connected with a connector which is used for connecting the water inlet pipe.

The central lines of the upper cylindrical pipe body and the lower cone of the fluid guide body and the central line of the submersible pump are on the same straight line.

The central lines of the large-diameter section, the small-diameter section and the variable-diameter section on the drainage cover are on the same straight line, and the central line of the drainage cover coincides with the central line of the submersible pump after the drainage cover is installed.

The ratio of the diameter of the bottom circle of the cone at the lower end of the drainage body to the height of the cone is 1/2-1/3.

According to the invention, the lower end of the submersible pump in the near-liquid level deep well sampling device is provided with the drainage fluid, and the drainage cover is sleeved on the peripheries of the drainage fluid and the submersible pump, so that the extracted water body enters from the lower end of the drainage cover and enters the submersible pump through the conical bottom annular cavity formed between the drainage cover and the drainage body, and thus the disturbance of the bottom plane of the pump to the water body can be reduced to the maximum extent; meanwhile, by means of a distribution mode that the sectional area of the inner cavity is gradually reduced from the water inlet pipe and the drainage cavity to the water outlet pipe, water flow in the near-liquid-level deep well sampling device is sufficient, instantaneous change of water pressure of a water body in the device is avoided, and precipitation of volatile substances in the water body is greatly reduced. The cooperative matching of the measures enables the fidelity of the collected water sample to be obviously improved. And, because the immersible pump only needs to set up under the liquid level, through the inlet tube of sub-unit connection and flower net pipe weight, has prolonged the water inlet of immersible pump downwards equivalently, and the immersible pump only needs to set up below the liquid level, just so in fact eliminates the lift restriction of immersible pump to can suck the water of arbitrary degree of depth, realize the extra-deep sampling.

In the underground water high-fidelity sampling system, in the sampling process, a water sample falls into the sampling bottle from the mesh pipe at the lower end of the sampling device of the deep well close to the liquid level and finally flows into the sampling bottle, and the flow rate of water pumping is controlled by adjusting the flow regulator, so that the sampled water flow flows stably, micro-disturbance water pumping can be realized, the overflow probability of volatile substances in the collected water sample is effectively reduced, and the fidelity of the water sample is improved. In the sampling process, the collected water sample is always in a closed environment, so that volatile substances are prevented from being separated from the water body, the fidelity of the collected water sample is ensured, and the problem that the water sample collected by the deep well is easy to distort is solved. In addition, the sampling device for the deep well with the liquid facing surface has a simple structure, is easy to clean, and can effectively solve the problem that cross contamination is easy to generate among samples due to the fact that the sampling device is difficult to clean. And moreover, the submersible pump in the near-liquid-level deep water well sampling device is arranged near the liquid level, so that the energy consumption of the whole sampling system can be reduced, and the deep water sampling cost is further reduced.

The second purpose of the invention is realized by the following steps: the underground water high-fidelity sampling system comprises the following steps:

a. setting a set of the underground water high-fidelity sampling system;

b. measuring the distance between the well water level in the water well to be sampled and the well mouth, and determining the throwing position of a submersible pump in the deep water sampling device near the liquid level in the water well to be sampled according to the distance so as to enable the water outlet of the submersible pump to be submerged below the well water level after throwing;

c. b, respectively calculating the distance between a filter at the lower part of the well pipe and the well water liquid level and the configuration length of a required water inlet pipe according to well pipe structure data of a water well to be sampled and measured distance data between the well water liquid level and a well mouth, intercepting the water inlet pipe with the corresponding length according to the calculation result, connecting the intercepted water inlet pipe between a drainage cover and a flower net pipe weight in the near-liquid level deep water sampling device, intercepting a water outlet pipe with the corresponding length according to the detection structure in the step b, and connecting a water outlet of the submersible pump with the quality stabilizer through the water outlet pipe;

d. the deep water sampling device facing the liquid level is placed in a water well to be sampled: the flower net pipe drop, the water inlet pipe, the submersible pump, the drainage cover and the water outlet pipe in the near-liquid-level deep water sampling device are put down from the wellhead of the sampling well in sequence, when the fact that the lowered submersible pump is completely submerged into the surface of the well water is determined according to the size marked on the pipe wall of the water outlet pipe, the lowering operation is stopped, at the moment, the water inlet pipe is straightened in the well pipe by the flower net pipe drop, and the flower net pipe drop is just suspended in the range of an underground water-bearing layer where a filter at the lower part of the well pipe is located;

e. calculating the total internal volume of the near-liquid-level deepwater sampling device, starting a submersible pump, pumping initially collected water which is not less than the total internal volume of the near-liquid-level deepwater sampling device into a wastewater collection device, observing a hydraulic display in a laminar flow sampler, and slowly adjusting a flow dividing controller and a concentric flow regulator in the laminar flow sampler to keep the reading of the hydraulic display at 0.2-0.3 Mpa;

f. keeping the water flow state unchanged, enabling the port of a sampling pipe of the vertical laminar flow sampler to be upright upwards to enable the height of the hemispherical water surface flowing out of the pipe end to be about 0.5cm, and simultaneously observing the interior of the sampling pipe without micro bubbles in a backlight manner to start sampling operation;

g. keeping the water flow state, inserting a sampling pipe of the laminar flow sampler into a sampling bottle, holding the sampling bottle by hand and keeping the sampling bottle in an upright state until the water level in the bottle slowly rises to corresponding scales on the sampling bottle required for collecting water samples;

h. and closing the concentric flow regulator on the quality stabilizer to stop the water flow entering the sampling bottle, sealing the sampling bottle, and placing the sampling bottle into a heat preservation box for constant-temperature storage.

Drawings

FIG. 1 is a schematic structural diagram of a groundwater high fidelity sampling system of the invention.

Fig. 2 is a schematic structural diagram of the liquid level facing deep water well sampling device.

Fig. 3 is a schematic structural view of the mass stabilizer.

Fig. 4 is a schematic diagram of the structure of a laminar flow sampler.

FIG. 5 is a sample of groundwater collected by the sampling method of the present invention and a conventional sampling method²²²And (3) comparison graph of Rn activity and concentration.

In the figure: 1. a sampling bottle; 2. a laminar flow sampler; 3. a mass stabilizer; 4. a well pipe; 5. a liquid level-facing deep well sampling device; 6. a filter; 51. a water outlet; 52. a submersible pump; 53. a drainage cover; 54. introducing a fluid; 55. a small diameter section; 56. a water inlet; 57. a water outlet pipe; 58. a water inlet pipe; 59. the lace pipe pendant; 31. an upper conical shell; 32. a lower cone shell; 33. quickly connecting a snap ring; 34. an observation window; 35. a pressure gauge; 36. a water pan; 37. a flow guide hole pipe; 38. a support bar; 39. a pipe clamp; 310. a communicating pipe; 311. a transparent hose; 312. a concentric flow regulator; 313. a support; 21. a sampling hose; 22. rotating the euphroe; 23. a holding rod; 24. plugging with a thread; 25. a valve plate; 26. passing through the shaft; 27. a pressure gauge; 28. a streamline water outlet; 29. a steady flow buffer tube; 210. a circular ring large pressing cap; 211. a large seal ring; 212. taking over a pipe tower seat; 213. a circular ring small pressing cap; 214. a small seal ring; 215. a C-shaped small top hook; 216. a C-shaped large top hook; 217. and (5) fastening the screw.

Detailed Description

As shown in figures 1 and 2, the groundwater high-fidelity sampling system comprises a near-liquid level deep well sampling device 5, a quality stabilizer 3, a laminar flow sampler 2 and a sampling bottle 1.

The near-liquid level deep water well sampling device 5 comprises a submersible pump 52, a drainage body 54, a drainage cover 53, a water inlet pipe 58, a perforated pipe dropping device 59 and the like.

The submersible pump 52 is a vertical cylindrical pump body, a water outlet 51 at the top of the pump body is connected with a water outlet pipe 57 for conveying collected water to the ground, and the pipe wall of the water outlet pipe 57 is marked with scale marks for indicating the length of the water outlet pipe 57.

The upper part of the fluid guiding body 54 is a cylindrical pipe body, the lower part of the fluid guiding body is a cone structure with the tip part arranged downwards, the fluid guiding body is installed at the lower end of the submersible pump 52, the upper end surface of the fluid guiding body 54 is in face-to-face connection with the lower end surface of the submersible pump 52, and the central lines of the upper cylindrical pipe body and the lower cone of the fluid guiding body 54 and the central line of the submersible pump 52 are in the same straight line. In the pumping and sampling process, the lower end of the drainage body 54 can gradually disperse the entering water, so that the water body can be prevented from colliding with the lower end of the submersible pump 52, the disturbance to the pumping water body is reduced, the stability of the water body is facilitated, and the fidelity of the sample is further improved.

The drainage cover 53 is of a cover body structure and covers the periphery of the submersible pump 52 and the drainage body 54. The flow guide cover 53 includes a large diameter section located at an upper portion, a small diameter section 55 located at a lower portion, and a variable diameter section for connecting the large diameter section and the small diameter section 55. The upper end of the large-diameter section of the drainage cover 53 is sealed on the pump body at the upper part of the water inlet 56 of the submersible pump 52, and the sealing part between the drainage cover 53 and the submersible pump 52 is sealed by adopting a transitional arc, so that the flowing water flow is stable, and the disturbed degree of the water body is reduced. The tapered section corresponds to the cone of the lower portion of the drainage body 54, and the taper of the tapered section is consistent with the taper of the lower end of the drainage body 54. The center lines of the large-diameter section, the small-diameter section 55 and the variable-diameter section on the flow guide cover 53 are on the same straight line, and after the flow guide cover 53 is installed, the center line of the flow guide cover 53 is coincident with the center line of the submersible pump 52. The diameter of the small diameter section of the drainage cover 53 is larger than that of the water outlet pipe 57, and the sectional area of the annular cavity formed between the large diameter section and the drainage body 54 is not larger than that of the small diameter section 55, so that water flow is stable when the water flows through the annular cavity during deep water sampling, and no negative pressure state occurs.

The upper end of the water inlet pipe 58 is connected with the small-diameter section 55 of the drainage cover 53, and the lower end is connected with the lattice net pipe pendant 59.

The screen pipe drop 59 is provided at the filter 6 provided at the lower end of the well pipe 4 of the deep well to collect filtered groundwater and provide gravity to the inlet pipe 58 in a straightened state. The structure of the flower net pipe drop 59 is that the bottom of a section of straight-wall flower net pipe is connected with a conical bottom plate, the top of the straight-wall flower net pipe is connected with an annular top plate, and the inner circle of the annular top plate is provided with a connector which is used for connecting a water inlet pipe 58.

The ratio of the diameter of the bottom circle of the cone at the lower end of the drainage body 54 to the height of the cone is 1/2-1/3, and the structural arrangement can make the flow direction change of water slow when underground water enters the annular space from the water inlet pipe 58, so that the disturbance to substances in the water is reduced as much as possible, the fidelity of a sample is improved, and the state change of unstable substances in the water is avoided.

The drainage cover 53 and the drainage body 54 are both made of corrosion-resistant rigid materials, so that corrosion is prevented from occurring, and the detection result of a collected water sample is influenced. The water outlet pipe 57 and the water inlet pipe 58 are both soft plastic pipes, so that the water storage and the use are convenient.

The mass stabilizer 3 may take the form of the structure disclosed in the CN205157233U patent. As shown in fig. 3, the quality stabilizer 3 includes a conical upper cone shell 31 and a conical lower cone shell 32 having the same taper and not more than 30 °, a cone bottom of the upper cone shell 31 and a cone bottom of the lower cone shell 32 are opening opposite ends with flanged ring edges, the two opening opposite ends are opposite to each other, and the two flanged ring edges are fixed and clamped by a snap ring 33 at the opposite part, so that the upper cone shell 31 and the lower cone shell 32 are fixedly connected into a whole. An observation window 34, a level bubble (not shown), a pressure gauge 35 and a water pan 36 are respectively arranged on the side wall of the upper cone shell 31. The two observation windows 34 are opposite and are symmetrically arranged on the axial lead of the conical shell 31. The level bubble is used for observing the setting verticality of the quality stabilizer 3. The pressure gauge 33 is used to measure the water pressure in the mass stabilizer 3. The water pan 36 surrounds and is fixedly connected to the outer wall of the upper conical shell 31, a flow guide hole pipe 37 for guiding flow to the outside of the pan is arranged on the water pan 36, and a flow guide pipe is connected to the flow guide hole pipe 37. The water pan 36 is used for receiving water samples flowing out from the upper port of the essential quantity stabilizer 3 or the sampling bottle, and then the water samples are intensively discharged through the guide pipe, so that the pollution to the sampling working surface is avoided. The outer wall of the upper conical shell 31 is further provided with a support rod 38, the upper end of the support rod 38 is transversely hinged with a pipe clamp 39, a communicating pipe 310 is fixedly connected in the pipe clamp 39, the communicating pipe 310 is communicated with a water outlet pipe opening arranged at the conical top of the upper conical shell 31 through a transparent hose 111, and the transparent hose is connected with a concentric flow regulator 312 so as to achieve the purpose of controlling the liquid flow through regulating and controlling the opening of the transparent hose. The concentric flow regulator 312 may be constructed as disclosed in the applicant's prior application CN103743594A patent. A bracket 313 for supporting the mass stabilizer is arranged on the lower conical shell, and a water inlet pipe orifice is arranged at the conical top (at the downward part) of the lower conical shell 32 and is used as an input port of the mass stabilizer.

The quality stabilizer 3 is arranged on the ground, the water inlet pipe end of the quality stabilizer is connected with the water outlet pipe 57 at the top of the submersible pump 52 of the liquid level facing deep well sampling device 5, and the water outlet end is communicated with the water inlet end of the laminar flow sampler 2, so that the quality stabilizer is mainly used for enabling each component molecule in a water sample collected by the liquid level facing deep well sampling device to reach a dynamic balance state again, namely escaping volatile components are re-dissolved in the water sample, and the authenticity of the water sample is ensured.

The laminar flow sampler 2 may take the form of the structure disclosed in the CN103743596B patent. As shown in fig. 4, the laminar flow sampler 2 includes a steady flow buffer tube 29, a pump tube connection mechanism, a split pressure regulating valve, a pressure gauge 27, a sampling hose 21, and a concentric flow regulator.

The steady flow buffer tube 29 is a cylindrical tube body made of 304 stainless steel and with two open ends, and an outer convex edge is arranged on the upper end of the steady flow buffer tube and provided with a pump tube connecting mechanism so as to realize fixed connection with the water sample output pipeline. A streamline water outlet 28 is arranged on the tube wall of the steady flow buffer tube 29, and the sampling hose 21 is fixedly connected on the outer end of the streamline water outlet 28. A shunt pressure regulating valve is arranged in the lower port of the steady flow buffer tube 29 and used for regulating the port opening of the steady flow buffer tube 29 so as to regulate the water flow pressure of the water sample in the tube body. In fig. 4, the pump pipe connection mechanism includes a connection pipe tower base 212, a circular ring large pressure cap 210, a large sealing ring 211, a C-shaped large top hook 216, a small sealing ring 214, a circular ring small pressure cap 213, a C-shaped small top hook 215, and the like. The adapter tower base 212 is made of 304 stainless steel and consists of a section of vertical pipe and a circular plate welded at the lower port of the vertical pipe, and the upper port of the vertical pipe is also provided with an outer convex edge; the outer diameter of the annular plate is the same as the outer diameter of the upper end of the constant flow buffer tube 29 so as to cover the upper end of the constant flow buffer tube. The vertical pipe is a group of serial circular pipes with the inner diameters about 2mm larger than the outer diameters of national standard serial pipelines, and comprises 10 specifications of DN125, DN100, DN80, DN65, DN50, DN40, DN32, DN25, DN20 and DN15, so that the connection pipe tower bases 12 form a group of serial size configurations, and the connection pipe bases corresponding to the pipe diameters of the vertical pipe can be selected for field assembly according to different connection pipelines used on the field, thereby realizing the reliable insertion fit of the sampling instrument and the pipelines. The connection tube tower base 212 is shielded on the upper port of the steady flow buffer tube 29, a large sealing ring 211 made of silica gel is lined between the upper port of the steady flow buffer tube 29 and a circular ring plate of the connection tube tower base 212, and a C-shaped large top hook 216 is buckled between the outer edge of the circular ring large pressure cap 210 and the outer convex edge of the upper end of the steady flow buffer tube 29 to clamp the circular ring large pressure cap 210 at the upper port of the steady flow buffer tube 29; then, the fastening screw 217 is used for screwing and positioning the C-shaped large top hook 216 on the top surface of the circular ring large pressure cap 210, so that the circular ring plate on the adapter tube tower base 212 is pressed on the upper port of the steady flow buffer tube 29, and the fixed connection of the pump tube connecting mechanism and the steady flow buffer tube 29 is realized.

The vertical pipe of the pipe connecting tower base 212 is matched with the water sample connecting pipeline in an inserting mode, and basically the same fixed connection mode is adopted. In fig. 4, a small sealing ring 214 made of silica gel and a small annular pressure cap 213 made of stainless steel are firstly sleeved on a pump pipe, a riser of a connection pipe tower base 212 on the sampler is sleeved on a port of the pump pipe, when the end of a connection pipeline is inserted into the riser port, the small sealing ring 214 is lined at the upper port of the riser, and then the small annular pressure cap 213 is pressed on the riser; the C-shaped small top hook 215 is buckled between the outer edge of the annular small pressing cap 213 and the outer convex edge of the upper end of the vertical pipe, so that the annular small pressing cap 213 is clamped at the upper port of the vertical pipe; then, the C-shaped small top hook 215 is screwed and positioned on the top surface of the annular small pressing cap 213 by using a fastening screw 217, and the small sealing ring 214 is tightly pressed at the upper port of the vertical pipe, so that the inner annular surface of the small sealing ring 214 deforms and squeezes the pump pipe, and thus, the stable connection between the water sample output pipeline and the vertical pipe is realized.

When the diameter of the water outlet of the pipeline is DN150, the pipeline can be directly spliced with the steady flow buffer tube 29; when the diameter of the water outlet of the pipeline is smaller than DN150, the pipeline can be spliced with the steady flow buffer tube 29 through the connecting pipe tower base 212.

The shunt pressure regulating valve arranged in the lower port of the steady flow buffer tube 29 can use various valves such as ball valves, butterfly valves, stop valves or gate valves. Fig. 4 shows a simple pressure-regulating shunt valve, which is constructed by forming a recessed notch in a through shaft 26, inserting a circular valve plate 25 into the notch and fixing the circular valve plate with screws, wherein a sealing ring (or not) can be arranged around the valve plate 5, and the valve plate 25 can be attached to the inner wall of a steady flow buffer tube 29 to block the lower port of the steady flow buffer tube 29.

The through shaft 26 passes through the plug-in interface on the right side of the tube wall of the steady flow buffer tube, the inner end of the through shaft is inserted into the clamping blind hole on the left side of the tube wall of the steady flow buffer tube, the exposed end of the through shaft 26 is connected with a handle in a penetrating way, and the valve plate 25 can be rotated by rotating the handle, so that the opening degree of the shunting pressure regulating valve is adjusted, and the water flow pressure of a water sample is regulated. A rubber ring (not shown) and a plug 24 are sealed in the socket on the right side of the tube wall. The adjustment of the shunt regulator valve is determined according to the indication of the pressure gauge 27.

The sampling hose 21 is a pressure-resistant transparent hose made of silica gel, one end of the sampling hose is connected to the outer port of the streamline water outlet 28, the other end of the sampling hose passes through the concentric flow regulator, and the water flow of the collected water sample is regulated through the concentric flow regulator. The concentric flow regulator is characterized in that an axial core hole is formed in a straight handle holding rod 23, a sampling hose 21 penetrates through the axial core hole of the straight handle holding rod 23, a rotary rope tightener 22 is arranged at the upper end of the holding rod 23, and the extending length of the free end of the sampling hose 21 penetrating out of the holding rod 23 is not less than 30cm, so that the sampling hose can be inserted into a sampling bottle to collect a water sample.

The laminar flow sampler 2 is arranged on the ground or on a support on the ground, the water inlet end of the laminar flow sampler is communicated with the water outlet end of the quality stabilizer 3, and the water outlet end is communicated with the water inlet end of the sampling bottle 1 to adjust the water flow pressure of the collected water sample and convey the water sample into the sampling bottle 1 in a stable manner.

The sample bottle 1 may take the form of the structure disclosed in the CN105181385B patent. The sampling bottle 1 is arranged on the ground or on a support arranged on the ground, is communicated with the laminar flow sampler 2 and is used for collecting the collected water sample discharged from the laminar flow sampler 2.

The invention relates to a near liquid level high-fidelity deepwater sampling method which comprises the following steps:

a. setting a set of underground water high-fidelity sampling system as described in example 1;

b. measuring the distance between the well water level in the water well to be sampled and the well mouth, and accordingly determining the throwing position of the submersible pump 52 in the near-liquid-level deep water sampling device 5 in the water well to be sampled, so that the water outlet 51 of the submersible pump 52 can be submerged below the well water level after throwing;

c. according to the well pipe structure data of the well to be sampled and the measured distance data between the well water liquid level and the well mouth, respectively calculating the distance between the filter 6 at the lower part of the well pipe and the well water liquid level and the configuration length of the required water inlet pipe 58, intercepting the water inlet pipe 58 with the corresponding length according to the calculation result, connecting the intercepted water inlet pipe 58 between the drainage cover 53 and the flower net pipe drop 59 in the near-liquid level deep water sampling device 5, intercepting the water outlet pipe 57 with the corresponding length according to the detection structure of the step b, and connecting the water outlet 51 of the submersible pump 52 with the quality stabilizer 3 through the water outlet pipe 57;

d. the liquid level deep water sampling device 5 is placed in the water well to be sampled: the flower net pipe drop 59, the water inlet pipe 58, the submersible pump 52, the drainage cover 53 and the water outlet pipe 57 in the near-liquid-level deep water sampling device 5 are put down from the wellhead of a sampling well in sequence, when the fact that the lowered submersible pump 52 is completely submerged into the well water level is determined according to the size marked on the wall of the water outlet pipe 57, the lowering operation is stopped, at the moment, the water inlet pipe 58 is straightened in a well pipe by the flower net pipe drop 59, and the flower net pipe drop 59 is just suspended in the range of an underground aquifer where the filter 6 at the lower part of the well pipe is located;

e. calculating the total internal volume of the near-liquid-level deepwater sampling device 5, starting a submersible pump 52, pumping the initially collected water body which is not less than the total internal volume of the near-liquid-level deepwater sampling device into a wastewater collection device, observing a hydraulic display in the laminar flow sampler 2, and slowly adjusting a flow distribution controller and a concentric flow regulator in the laminar flow sampler 2 to keep the reading of the hydraulic display at 0.2-0.3 Mpa;

g. keeping the water flow state, inserting the sampling pipe of the laminar flow sampler 2 into the sampling bottle, holding the sampling bottle by hand and keeping the sampling bottle in an upright state until the water level in the bottle slowly rises to corresponding scales on the sampling bottle required for collecting water samples;

h. and closing the concentric flow regulator on the quality stabilizer 3 to stop the water flow entering the sampling bottle, sealing the sampling bottle, and placing the sampling bottle into a heat preservation box for constant-temperature storage.

A sampling site is provided with No. 1-6 sampling wells numbered in sequence, the sampling method and the conventional sampling method are respectively adopted to collect water bodies in the No. 1-6 sampling wells, and the water bodies in the sampled water bodies are²²²And the Rn activity concentration is used as a comparative reference object. Through comparison, the water body collected by the sampling method of the invention²²²The activity and concentration of Rn are higher than those of the water body obtained by conventional sampling²²²The specific numerical values of the activity concentration of Rn are shown in FIG. 5, so that the water sample collected by the sampling method disclosed by the invention is higher in fidelity, and the detection result of the sample can be more accurate, therefore, the sampling method disclosed by the invention has good popularization and application values.

Claims

1. The utility model provides an underground water high fidelity sampling system, characterized by includes:

the liquid level near deep well sampling device is used for pumping underground water in a water-bearing layer corresponding to the burial depth of the filter in the deep well, the pumping equipment is arranged below the liquid level in the deep well and close to the liquid level, the water inlet port of the pumping equipment is submerged to the position of the filter in the deep well through the connecting pipeline, and the underground water in the water-bearing layer corresponding to the filter is pumped;

the sampling bottle is used for collecting the water sample output by the laminar flow sampler;

face liquid level deep water well sampling device includes:

2. A groundwater hi-fi sampling system as claimed in claim 1, wherein the centerlines of the upper cylindrical pipe body and the lower cone of the diversion fluid are aligned with the centerline of the submersible pump.

3. The groundwater high fidelity sampling system of claim 1, wherein the center lines of the large diameter section, the small diameter section and the reducing diameter section on the flow guide cover are in a straight line, and after installation, the center line of the flow guide cover coincides with the center line of the submersible pump.

4. A groundwater high fidelity sampling system as claimed in claim 1, wherein the ratio of the diameter of the base circle of the cone at the lower end of the flow guide to the height of the cone is between 1/2-1/3.

5. The underground water high-fidelity sampling method is characterized by comprising the following steps of:

a. setting a set of underground water high fidelity sampling system of claim 1;

d. the deep water sampling device facing the liquid level is placed in a water well to be sampled: the flower net pipe drop, the water inlet pipe, the submersible pump, the drainage cover and the water outlet pipe in the near-liquid-level deep water sampling device are put down from the wellhead of the sampling well in sequence, when the fact that the lowered submersible pump is completely submerged into the surface of the well water is determined according to the size marked on the pipe wall of the water outlet pipe, the lowering operation is stopped, at the moment, the water inlet pipe is straightened in the well pipe by the flower net pipe drop, and the flower net pipe drop is just suspended in the thickness range of an underground water-bearing layer where a filter at the lower part of the well pipe is located;