Hydrodynamic groundwater layered pumping system

Abstract

The application discloses a liquid-driven groundwater layered pumping system, which comprises a water outlet pipe, an upper packer, a lower packer and a submersible pump arranged in a well pipe, wherein the upper packer, the submersible pump and the lower packer are sequentially arranged on the water outlet pipe from top to bottom, the upper packer and the lower packer are arranged in an aquiclude of the well pipe, and the submersible pump is arranged in an aquifer of the well pipe; the liquid-driven groundwater layered pumping system further comprises a press pump arranged on the ground and connected with a pipe opening of the water outlet pipe, and the upper packer and the lower packer are connected through a hydraulic pipeline to realize equalization of setting pressure.

Description

Technical Field

[0001] This invention relates to the field of hydrogeological survey technology, and in particular to a hydraulically driven stratified groundwater pumping system. Background Technology

[0002] Groundwater is typically distributed across aquifers at varying depths, separated by impermeable layers. The hydrological parameters of each aquifer, such as water level, hydrochemical characteristics, and hydrodynamic parameters, generally differ. During hydrological well construction, multiple aquifers are usually encountered within a single well, failing to accurately reflect the characteristics of each aquifer. Therefore, stratified monitoring methods are necessary when required. Early stratified groundwater monitoring often employed single-well, single-layer monitoring, where each well monitored one aquifer layer. This required constructing numerous wells, resulting in high costs and large land areas. Multi-layer monitoring with single wells is the trend and inevitable development, necessitating the use of stratified groundwater pumping systems.

[0003] The current groundwater stratified pumping systems all use gas-driven packer expansion sealing, so gas lines must be attached to the tubing string that is lowered into the well. (1) The gas lines have low strength, poor sealing of the joints, and a large number of gas line joints. In order to ensure that the design well section is reached smoothly, extra length of gas lines are required at the wellhead. The gas pressure loss along the way is large, and the packer is prone to wear, leakage, and depressurization during the well entry process, which may lead to packer failure or continuous pressure replenishment during use. (2) During the deep aquifer pumping test, due to the high water pressure in the deep aquifer, the gas drive is difficult to offset the influence of the high water pressure, and the packer expansion is difficult or even fails. The stratified pumping system driven by gas pressure is not suitable for deep aquifer exploration. A hydraulic groundwater stratified pumping system is needed to solve the above problems. Summary of the Invention

[0004] The main objective of this invention is to provide a hydraulically driven stratified groundwater pumping system, which aims to solve the problems of low strength and easy wear of existing gas pipelines and the difficulty of gas to counteract high water pressure.

[0005] To achieve the above objectives, the technical solution proposed by the present invention is: a hydraulically driven groundwater stratified pumping system, comprising an outlet pipe, an upper packer, a lower packer, and a submersible pump placed in a well pipe, wherein the upper packer, the submersible pump, and the lower packer are fixedly mounted on the outlet pipe from top to bottom, the upper packer and the lower packer are both placed in the water-proof layer of the well pipe, and the submersible pump is placed in the aquifer of the well pipe; It also includes a pressure pump, which is placed on the ground and connected to the outlet of the water pipe. The upper packer and the lower packer are connected by a hydraulic line to achieve equalization of the setting pressure. It also includes a hydraulic flow direction switching component disposed on the outlet pipe, the hydraulic flow direction switching component being configured to: guide water to the upper packer and the lower packer when the pressure pump pressurizes the outlet pipe, so that the upper packer and the lower packer expand and set; and allow the groundwater of the aquifer to flow unidirectionally from bottom to top in the outlet pipe when the submersible pump pumps water.

[0006] Preferably, the hydraulic flow direction switching component includes a first check valve and a bypass check valve. The first check valve is disposed in the outlet pipe above the upper packer, and the conduction direction of the first check valve is from bottom to top. The bypass check valve is located between the outer wall of the outlet pipe and the upper packer, and the conduction direction of the bypass check valve is from the inside of the outlet pipe to the upper packer.

[0007] Preferably, the hydraulic pipeline extends longitudinally along the outer wall of the water outlet pipe.

[0008] Preferably, the inlet of the bypass check valve is connected to the internal cavity of the outlet pipe, and the inlet is located above the first check valve.

[0009] Preferably, the hydraulic flow direction switching component includes a second check valve and a check valve. The second check valve is disposed in the outlet pipe between the upper packer and the submersible pump, and the conduction direction of the second check valve is from bottom to top. The outlet pipe has a flow passage hole on its wall, which is located above the second one-way valve. The flow passage hole is connected to the upper packer through a connecting pipe. The check valve is installed on the connecting pipe, and the flow direction of the check valve is from the inside of the outlet pipe to the upper packer.

[0010] Preferably, both the upper packer and the lower packer are hydraulically set and lift-up release type packers.

[0011] Preferably, the bottom of the water outlet pipe is provided with a bottom plug, which is used to seal the bottom port of the water outlet pipe.

[0012] Preferably, the system also includes a groundwater monitoring instrument installed on the outer wall of the outlet pipe. The groundwater monitoring instrument includes an upper water level gauge and a lower water level gauge. The upper water level gauge is installed above the upper packer, and the lower water level gauge is installed on the outlet pipe section between the upper packer and the lower packer.

[0013] Preferably, a filter screen is provided at the inlet of the bypass check valve.

[0014] Compared with existing technologies, this invention has at least the following advantages: This invention eliminates the need for independently installed gas pipelines in traditional gas-driven systems, utilizing the water outlet pipe itself as a pressurization channel. Through the cooperation of a one-way valve and a bypass one-way valve, the water outlet pipe achieves "dual-purpose" operation, serving both pressurization and water extraction, significantly simplifying the downhole tubing structure and fundamentally avoiding the problem of setting failure caused by gas pipeline wear and leakage. Simultaneously, this invention uses water as the hydraulic setting medium. Liquids are incompressible and their driving force is far greater than that of gas, effectively overcoming the resistance of high water pressure at depths, ensuring reliable packer setting, and filling the technological gap where existing gas-driven systems are not suitable for deep aquifers. Furthermore, the pressurization setting and lifting unsealing operations are simple and efficient, and the tubing can be directly adjusted to the next aquifer for continued testing, significantly improving operational efficiency. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0016] Figure 1 This is a structural diagram of Embodiment 1 of the present invention; Figure 2 This is a structural diagram of Embodiment 2 of the present invention.

[0017] Explanation of reference numerals in the attached figures: 1. Outlet pipe; 2. Upper packer; 3. Lower packer; 4. Pressure pump; 5. Bypass check valve; 6. First check valve; 7. Second check valve; 8. Hydraulic pipeline; 9. Submersible pump.

[0018] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] It should be noted that all directional indications in the embodiments of the present invention are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0021] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0022] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0023] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0024] Example 1 This invention proposes a hydraulically driven stratified groundwater pumping system.

[0025] As attached Figure 1 As shown, the hydraulically driven groundwater stratified pumping system proposed in this invention includes an outlet pipe 1, an upper packer 2, a lower packer 3, and a submersible pump 8 placed in a well pipe. The upper packer 2, the submersible pump 8, and the lower packer 3 are fixed to the outlet pipe 1 from top to bottom. The upper packer 2 and the lower packer 3 are both placed in the water-proof layer of the well pipe, and the submersible pump 8 is placed in the water-bearing layer of the well pipe. It also includes a pressure pump 4, which is placed on the ground and connected to the outlet of the water pipe 1. The upper packer 2 and the lower packer 3 are connected by a hydraulic line 7 to achieve equalization of the setting pressure. It also includes a hydraulic flow direction switching component installed on the outlet pipe 1. The hydraulic flow direction switching component is configured to: when the pressure pump 4 pressurizes the outlet pipe 1, guide water to the upper packer 2 and the lower packer 3 (add sufficient water to the outlet pipe in advance, and then pressurize the water into the upper packer 2 and the lower packer 3 by the pressure pump 4), so that the upper packer 2 and the lower packer 3 expand and set; when the submersible pump 8 pumps water, allow the groundwater of the aquifer to flow unidirectionally from bottom to top in the outlet pipe 1.

[0026] Specifically, the outlet pipe 1 is made of steel, and its outer wall can be fixed to the upper packer 2, lower packer 3, and submersible pump 8 by threaded connection or flange connection. The outlet of the pressure pump 4 is connected to the surface port of the outlet pipe 1 through a high-pressure hose or steel pipe. The pressure pump 4 can be a plunger pump or a centrifugal pump, preferably a plunger pump to provide a stable high-pressure water source, with an operating pressure range of 2-20 MPa. The upper packer 2 and lower packer 3 are connected by a hydraulic line 7 with an inner diameter of 3-8 mm, used to synchronously transmit pressurized water to the two packers to keep their setting pressure consistent. The hydraulic flow direction switching component is set on the outlet pipe 1. Its implementation is not limited to a combination of check valves; it can also be replaced by components with flow direction control functions such as slide valves or reversing valves, as long as it meets the basic functions of guiding water into the packers during pressurization and allowing upward water to pass through during pumping. The "water" mentioned in this invention can be surface water or groundwater directly taken from the well pipe.

[0027] This invention eliminates the need for a separate gas pipeline in traditional gas-driven systems. Instead, it utilizes the water outlet pipe itself as a pressurization channel. Through the cooperation of a one-way valve and a bypass one-way valve, the water outlet pipe achieves a "dual-purpose" function, serving both for pressurization and water extraction. This significantly simplifies the downhole tubing structure and fundamentally avoids the problem of setting failure caused by gas pipeline wear and leakage. Furthermore, this invention uses water as the hydraulic setting medium. Liquids are incompressible and their driving force is far greater than that of gas, effectively overcoming the resistance of high water pressure at depths and ensuring reliable packer setting. This fills the technological gap where existing gas-driven systems are not suitable for deep aquifers. In addition, the pressurization and setting, and lifting for unsealing operations are simple and efficient. The tubing can be directly adjusted to the next aquifer for continued testing, significantly improving operational efficiency.

[0028] Preferably, the hydraulic flow direction switching component includes a first one-way valve 6 and a bypass one-way valve 5. The first one-way valve 6 is disposed in the water outlet pipe 1 above the upper packer 2, and the conduction direction of the first one-way valve 6 is from bottom to top. The bypass check valve 5 is disposed between the outer wall of the outlet pipe 1 and the upper packer 2, and the conduction direction of the bypass check valve 5 is from the inside of the outlet pipe 1 to the upper packer 2.

[0029] Specifically, the first check valve 6 can be a floating valve, also called a non-return valve, commonly used in downhole oilfield tools, and one-way conduction from bottom to top can be achieved by inversely installing its valve core. A sealing ring is provided between the outer wall of the first check valve 6 and the inner wall of the water outlet pipe 1 to prevent fluid from forming bypass flow between the outer wall of the valve body and the pipe wall. The bypass check valve 5 is arranged between the outer wall of the water outlet pipe 1 and the upper packer 2, and a spring-return check valve can be selected for its structure, and the opening pressure is preferably 0.1-0.5 MPa, so as to ensure that the valve can be opened smoothly during pressure pumping. In the working state, when the pressure pump 4 operates, the pressure in the water outlet pipe 1 is P1, the pressure in the packer is P2, and the bypass check valve 5 opens when P1>P2 and closes when P1<P2. When the submersible pump 8 pumps water, the water in the packer is locked, so the upper packer 2 and the lower packer 3 maintain the setting state, which is the core of the pressure holding function of the present invention.

[0030] Preferably, the hydraulic pipeline 7 extends longitudinally along the outer wall of the water outlet pipe 1.

[0031] Specifically, the hydraulic pipeline 7 is made of high-pressure wear-resistant material, such as stainless steel braided hydraulic hose or thick-walled seamless steel pipe, which can withstand an internal pressure of not less than 30 MPa. During installation, the hydraulic pipeline 7 is fixed to the outer wall of the water outlet pipe 1 at intervals by pipe clamps or binding straps, and the spacing of the pipe clamps is preferably 1-2 meters, so as to prevent the pipeline from shaking, tangling or wearing during the lowering of the well pipe. The upper end and the lower end of the hydraulic pipeline 7 are respectively in sealed communication with the hydraulic cavity interfaces of the upper packer 2 and the lower packer 3 through tapered threads or ferrule type joints, so as to ensure no leakage during pressure transmission.

[0032] Preferably, the liquid inlet of the bypass check valve 5 is communicated with the inner pipe cavity of the water outlet pipe 1, and the liquid inlet is located above the first check valve 6.

[0033] Specifically, the liquid inlet of the bypass check valve 5 is located above the first check valve 6. This arrangement makes the flow direction of the pressurized water restricted by the valve core of the first check valve 6, and can directly act on the liquid inlet of the bypass check valve 5, thereby reducing the along-path pressure loss and improving the pressure pumping efficiency. The specific implementation of the liquid inlet is as follows: a through hole is opened on the pipe wall of the water outlet pipe 1, the inner end of the through hole is communicated with the inner pipe cavity of the water outlet pipe 1, and the outer end is in sealed connection with the liquid inlet of the bypass check valve 5. The aperture of the through hole is preferably 5-10 mm, and the edge of the through hole is chamfered to prevent damage to the sealing element of the bypass check valve 5.

[0034] Preferably, both the upper packer 2 and the lower packer 3 are hydraulic setting and upward pulling releasing packers.

[0035] Specifically, hydraulically set and lift-up release packers are mature commercial products in the oil drilling industry. Their basic structure includes a central tube, a rubber sleeve fitted over the central tube, and a locking and releasing mechanism located below the rubber sleeve. When high-pressure water enters the packer's hydraulic chamber, it pushes the piston to compress the rubber sleeve, causing it to expand radially and adhere tightly to the inner wall of the well casing. Simultaneously, the locking mechanism locks the piston position to maintain continuous expansion of the rubber sleeve. When release is required, the water pipe 1 is lifted to the preset release tonnage, the pressure relief port in the release mechanism opens, the hydraulic pressure inside the rubber sleeve is released, and it contracts back to its initial size under its own elastic restoring force, thus achieving release. The setting pressure can be adjusted according to the depth and water pressure of the target aquifer, preferably 5-20 MPa; the release tonnage is preferably 5-10 tons, and the specific values ​​can be adjusted by those skilled in the art based on the rubber sleeve size and well depth.

[0036] Preferably, the bottom of the water outlet pipe 1 is provided with a bottom plug, which is used to seal the bottom port of the water outlet pipe 1.

[0037] Preferably, it also includes a groundwater monitoring instrument installed on the outer wall of the outlet pipe 1. The groundwater monitoring instrument includes an upper water level gauge and a lower water level gauge. The upper water level gauge is installed above the upper packer 2, and the lower water level gauge is installed on the outlet pipe section between the upper packer 2 and the lower packer 3.

[0038] Specifically, both the upper and lower water level gauges are preferably pressure-type or float-type water level gauges, with a measurement accuracy of no less than ±0.1%FS full scale. The sampling frequency can be set from 1 time / second to 1 time / hour, adjusted according to experimental requirements. The upper water level gauge is installed on the outer wall of the outlet pipe 1 above the upper packer 2, in the non-target aquifer above the upper impermeable layer, to monitor water level changes in this layer. The lower water level gauge is installed on the outer wall of the outlet pipe 1 between the upper packer 2 and the lower packer 3, i.e., within the target pumping aquifer, to monitor water level changes in the target aquifer. Data from both water level gauges are transmitted to a data acquisition instrument on the surface via their respective cables or data lines. By comparing the data from the two water level gauges, the sealing effectiveness of the packer can be determined: if the water level in the upper water level gauge does not change significantly during pumping, it indicates that the upper packer is sealing well; if the water level in the upper water level gauge drops synchronously, it indicates that the packer seal has failed. As a preferred extension, groundwater monitoring instruments may also include water quality sensors such as conductivity sensors, pH sensors, dissolved oxygen sensors, and temperature sensors.

[0039] Preferably, a filter screen is provided at the inlet of the bypass check valve 5.

[0040] Example 2 like Figure 2As shown, this embodiment provides another parallel implementation of the hydraulic flow direction switching component, which includes a second one-way valve 61 and a check valve. The second one-way valve 61 is disposed in the outlet pipe 1 between the upper packer 2 and the submersible pump 8, and the conduction direction of the second one-way valve 61 is from bottom to top. The outlet pipe 1 has a flow hole on its wall. The flow hole is located above the second one-way valve 61. The flow hole is connected to the upper packer 2 through a connecting pipe. The check valve is installed on the connecting pipe, and the flow direction of the check valve is from the inside of the outlet pipe 1 to the upper packer 2.

[0041] Specifically, the second check valve 61 is installed on the internal section of the outlet pipe 1 between the upper packer 2 and the submersible pump 8, and its installation method is the same as that of the first check valve 6. The flow-through hole on the wall of the outlet pipe 1 is located above the second check valve 61, and its diameter is preferably 5-10 mm. The flow-through hole is connected to the inlet of the upper packer 2 via a connecting pipe, which is a rigid steel pipe, and its outer wall is welded to the outer wall of the outlet pipe 1 for fixation and sealing. A check valve 62 is installed on the connecting pipe, and its conduction direction is from inside the outlet pipe 1 to the upper packer 2. The opening pressure of the check valve 62 is preferably 0.1-0.5 MPa, and its function is exactly the same as that of the bypass check valve 5, both preventing backflow of pressurized water inside the packer.

[0042] As another optional implementation, a filter screen can also be installed at the flow passage to prevent solid particles from entering the packer hydraulic chamber through the connecting pipeline. Compared with Embodiment 1, this embodiment places the second check valve 61 between the upper packer 2 and the submersible pump 8, so that the section of the outlet pipe 1 above the upper packer 2 does not need to be equipped with a check valve. This is more adaptable to scenarios where other instruments and equipment need to be installed on the upper part of the tubing. In addition, the second check valve 61 is closer to the submersible pump 8, resulting in less pressure loss of the upward water flow during pumping, which is beneficial to improving the pumping efficiency of the submersible pump 8.

[0043] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A hydraulically driven stratified groundwater pumping system, characterized in that, The well includes a water outlet pipe (1), an upper packer (2), a lower packer (3), and a submersible pump (8) placed in the well casing. The upper packer (2), the submersible pump (8), and the lower packer (3) are fixed on the water outlet pipe (1) from top to bottom. The upper packer (2) and the lower packer (3) are both placed in the water-proof layer of the well casing, and the submersible pump (8) is placed in the aquifer of the well casing. It also includes a pressure pump (4), which is placed on the ground and connected to the outlet of the water pipe (1). The upper packer (2) and the lower packer (3) are connected by a hydraulic line (7) to achieve equalization of the setting pressure. It also includes a hydraulic flow direction switching component installed on the outlet pipe (1), which is configured to: guide water to the upper packer (2) and the lower packer (3) when the pressurizing pump (4) pressurizes the outlet pipe (1) so that the upper packer (2) and the lower packer (3) expand and set; and allow the groundwater of the aquifer to flow unidirectionally from bottom to top in the outlet pipe (1) when the submersible pump (8) pumps water.

2. The hydraulically driven stratified groundwater pumping system according to claim 1, characterized in that, The hydraulic flow direction switching component includes a first check valve (6) and a bypass check valve (5). The first check valve (6) is located in the outlet pipe (1) above the upper packer (2), and the first check valve (6) is in the direction of flow from bottom to top. The bypass check valve (5) is located between the outer wall of the outlet pipe (1) and the upper packer (2), and the conduction direction of the bypass check valve (5) is from the inside of the outlet pipe (1) to the upper packer (2).

3. The hydraulically driven stratified groundwater pumping system according to claim 1, characterized in that, The hydraulic pipeline (7) extends longitudinally along the outer wall of the water outlet pipe (1).

4. The hydraulically driven stratified groundwater pumping system according to claim 2, characterized in that, The inlet of the bypass check valve (5) is connected to the internal cavity of the outlet pipe (1), and the inlet is located above the first check valve (6).

5. The hydraulically driven stratified groundwater pumping system according to claim 1, characterized in that, The hydraulic flow direction switching component includes a second check valve (61) and a check valve. The second check valve (61) is located in the outlet pipe (1) between the upper packer (2) and the submersible pump (8), and the conduction direction of the second check valve (61) is from bottom to top. The outlet pipe (1) has a flow hole on its wall. The flow hole is located above the second one-way valve (61). The flow hole is connected to the upper packer (2) through a connecting pipe. The check valve is installed on the connecting pipe, and the direction of the check valve is from the inside of the outlet pipe (1) to the upper packer (2).

6. The hydraulically driven stratified groundwater pumping system according to claim 1, characterized in that, Both the upper packer (2) and the lower packer (3) are hydraulically seated and lift-up release type packers.

7. The hydraulically driven stratified groundwater pumping system according to claim 1, characterized in that, The bottom of the water outlet pipe (1) is provided with a bottom plug, which is used to seal the bottom port of the water outlet pipe (1).

8. A hydraulically driven stratified groundwater pumping system according to claim 1, characterized in that, It also includes a groundwater monitoring instrument installed on the outer wall of the outlet pipe (1). The groundwater monitoring instrument includes an upper water level gauge and a lower water level gauge. The upper water level gauge is installed above the upper packer (2), and the lower water level gauge is installed on the outlet pipe section between the upper packer (2) and the lower packer (3).

9. A hydraulically driven stratified groundwater pumping system according to claim 2, characterized in that, The bypass check valve (5) is equipped with a filter screen at its inlet.

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