Automatic recovery treatment and reutilization system for accumulated liquid of square well

Abstract

The invention discloses an automatic recovery, purification and reutilization system for accumulated liquid in a square well, and belongs to the technical field of accumulated liquid recycling, the automatic recovery, purification and reutilization system comprises a water treatment device connected with an accumulated liquid pit at the bottom of the square well, and a submersible pump is arranged in the accumulated liquid pit and used for pumping the accumulated liquid into the water treatment device; the water treatment device comprises a purification tank and a water storage tank which are communicated with each other, the purification tank is connected with an outlet of the submersible pump and is used for purifying the accumulated liquid, and the water storage tank is used for storing the purified accumulated liquid; the water storage tank is connected with the cleaning machine and provides cleaning water for the cleaning machine, and the cleaning machine and the submersible pump are both connected with and controlled by the control box. The device can realize automatic suction, purification, storage and recycling of the accumulated liquid in the square well, and has the advantages of convenience in use, low cost, good safety and high water resource utilization efficiency.

Description

Technical Field

[0001] The invention relates to a processing device for square well accumulated liquid, and in particular to an automatic recovery, purification and reuse system for square well accumulated liquid. Background Art

[0002] In the field of natural gas production, gas wells are dispersed within the Guangmao gas field. After the gas wells are drilled, there is generally a square well below the ground at the wellhead position. A gas wellhead device is installed in the square well, and the upper part of the square well cannot be closed, resulting in rainwater gathering in the square well on rainy days to form accumulated liquid. The accumulated liquid will contain lubricating oil required for flushing the wellhead device for maintenance, oil stains left over from wellhead operations, etc., resulting in the inability to directly discharge the accumulated liquid. The accumulated liquid increases in the square well, and the rising liquid level will cause the wellhead device in the square well to be submerged, which brings inconvenience to the operation, maintenance and operation of the wellhead device. At the same time, the wellhead device in an immersed state will accelerate corrosion, increase the maintenance cost of the wellhead device equipment, and reduce its service life.

[0003] The existing treatment measures generally use submersible pumps to regularly pump the accumulated liquid in the square wells into tank trucks, and then transport it to the gas field water reinjection station for reinjection treatment. This method has the following main problems: First, the square wells are scattered and generally far away from the gas field water reinjection station, and the cost of tank truck transportation and reinjection is high; second, the square wells are mostly located in remote areas, and not every square well has power available near the site, so it is necessary to bring its own power generation equipment or internal combustion engine direct drive pump, which increases the difficulty and cost of recovering the accumulated liquid in the square wells.

[0004] In the prior art, patent CN202220709387.8 discloses a siphon-type square well liquid discharge device, which has a simple structure and does not require external energy, but requires on-site operation each time the liquid is discharged, and the accumulated liquid is discharged directly on-site. The discharge of accumulated liquid containing oil and floating oil will cause pollution to the surrounding land. Patent CN202022109630.6 discloses another natural gas well square well liquid discharge device, which also adopts the siphon principle to achieve the discharge of accumulated liquid. Although this method can achieve automatic discharge during liquid discharge without the need for on-site operation by personnel, it also does not deal with the existing floating oil. Patent CN202210245486.X discloses a manual device for pumping out accumulated liquid from an external well. The device adopts a mechanical structure for manual operation and does not require the use of an external power supply, but the treatment of accumulated liquid still adopts on-site discharge, which is not conducive to environmental protection.

[0005] In addition to being detrimental to environmental protection, the above technical measures do not reasonably reuse the accumulated liquid. In the natural gas wellhead area, the water-jacketed furnace used to heat the natural gas, equipment maintenance, and on-site cleaning after operation all require the use of clean water. Discharging the accumulated liquid on site means that there is no water available when water is needed, and clean water needs to be transported from a distance to the site, which is not only a waste of water resources, but also increases the cost of use. In view of this, it is urgent to study an automatic recovery, purification and reuse system for the accumulated liquid in the square well. Summary of the invention

[0006] The present invention aims to solve the above problems in the prior art and proposes an automatic recovery, purification and reuse system for square well liquid accumulation, which can significantly reduce the cost of square well liquid accumulation treatment and realize the rational reuse of water resources.

[0007] In order to achieve the above-mentioned object of the invention, the technical solution of the present invention is as follows: A system for automatically recovering, purifying and reusing accumulated liquid in a square well, characterized in that it comprises a water treatment device connected to a liquid accumulation pit at the bottom of the square well, a submersible pump is provided in the liquid accumulation pit, and the submersible pump is used to pump the accumulated liquid into the water treatment device; the water treatment device comprises a purification box and a water storage tank that are connected to each other, the purification box is connected to the outlet of the submersible pump and is used for purifying the accumulated liquid, and the water storage tank is used to store the accumulated liquid after purification; the water storage tank is connected to a cleaning machine to provide cleaning water for the cleaning machine, and the cleaning machine and the submersible pump are both connected to a control box for control.

[0008] Furthermore, the water treatment device also includes a water treatment agent storage tank and a filling pump, and the filling pump is used to pump the agent in the water treatment agent storage tank into the purification tank to mix with the accumulated liquid to achieve purification treatment.

[0009] Furthermore, a liquid level monitoring device is provided in the liquid accumulation pit, and the liquid level monitoring device is electrically connected to the control box to realize linkage control together with the submersible pump and the filling pump.

[0010] Furthermore, the inner part of the purification box is filled with oil-absorbing felt, active adsorption particles, gravel, and filter cloth in layers, and the top of the filler is spaced a distance away from the submersible pump and the filling pump.

[0011] Furthermore, a through hole communicating with the water storage tank is provided on the bottom side of the purification box.

[0012] Furthermore, an overflow port is provided at the upper part of the water tank body, the overflow port opening is lower than the outlets of the submersible pump and the filling pump, and a sewage valve is provided at the bottom of the water tank body.

[0013] Furthermore, the cleaning machine is equipped with a cleaning pipe and a water gun. The cleaning machine is driven by a control box connected to a power source, and the start / stop of the cleaning machine is manually controlled by a control knob on the control box panel.

[0014] Furthermore, it also includes a solar power supply system, which includes a solar panel, a battery storage device, and a bracket. The solar panel is supported by the bracket, and the bracket is installed on the water treatment device; the solar panel is connected to the battery storage device, and the battery storage device is connected to the control box.

[0015] Furthermore, a fully openable waterproof box cover is provided on the top of the water treatment device, and the side of the electric control box for installing the storage device, control box, and cleaning machine is designed as a side door, and dust-proof and waterproof ventilation holes are provided on both sides of the electric control box or on the side door.

[0016] Furthermore, the filling pump outlet pipe is provided with a flow regulating valve for controlling the filling amount of the water treatment agent.

[0017] In summary, the present invention has the following advantages: 1. The present invention can realize the automatic suction, purification, storage and reuse of the accumulated liquid in the square well, and has the advantages of convenient use, low cost, good safety and high water resource utilization efficiency; 2. The present invention is used for the recovery and reuse of square well liquid accumulation, which can significantly reduce the cost of existing manual drainage, vehicle transportation and water reinjection; 3. In the present invention, since the submersible pump device adopts automatic liquid level control and drainage, unattended operation can be achieved, ensuring that there is no liquid accumulation in the square well, and avoiding corrosion of the wellhead device due to long-term immersion in the liquid accumulation; 4. In the present invention, the purification system of the device can flexibly select suitable water treatment agents and physical purification fillers according to the water properties of the effluent to ensure that the purified water meets the local utilization and discharge standards; 5. The system of the present invention adopts low-voltage DC power supply, which can significantly reduce the safety risks of oil and gas production sites; 6. The whole set of the device of the present invention can be installed in a centralized skid to reduce the manufacturing, installation and use costs, and can also be powered by solar energy when not connected to the mains. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the automatic recovery, purification and reuse system of square well liquid accumulation used in a specific embodiment of the present invention; Figure 2 for Figure 1 Schematic diagram of the functional division of the reclaimed water treatment plant (top view); Figure 3 for Figure 2 Schematic diagram of the structure of the water purification treatment part; Figure 4 for Figure 2 Schematic diagram of the structure of the power storage, control and cleaning machine installation parts; In the figure: 1. Square well, 2. Liquid accumulation pit, 3. Submersible pump, 4. Liquid level monitoring device, 5. Submersible pump outlet pipeline, 6. Monitoring device wiring, 7. Water treatment device, 9. Water storage tank, 10. Electric control box, 11. Overflow port, 12. Drain valve, 13. Solar panel, 14. Bracket, 15. Ventilation hole, 16. Water treatment agent storage tank, 17. Purification tank, 18. Oil-absorbing felt, 19. Active adsorption particles, 20. Filter cloth, 21. Through hole, 22. Filling pump, 23. Filling pump outlet pipe, 24. Storage battery, 25. Control box, 26. Cleaning machine, 27. Cleaning pipe and water gun. DETAILED DESCRIPTION

[0019] In order to explain the present invention more clearly, the present invention is further described below in conjunction with preferred embodiments and drawings. It should be understood by those skilled in the art that the content described below is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0020] Example 1 The present invention provides a system for automatically recovering, purifying and reusing accumulated liquid in a square well. Figure 1 As shown, it includes a liquid accumulation pit 2 and a water treatment device 7 connected thereto.

[0021] The liquid accumulation pit 2 is arranged at the bottom of the square well 1. When rainwater or underground seepage water enters the square well 1, it first gathers in the liquid accumulation pit 2, which is convenient for sucking the accumulated liquid. An electric submersible pump 3 is installed in the liquid accumulation pit 2, and the outlet pipeline of the submersible pump 3 is connected to the purification box 17 in the water treatment device 7.

[0022] In this embodiment, Figure 2 The figure shows a functional schematic diagram of the partitioning of the water treatment device 7 , which includes a water treatment agent storage tank 16 , a filling pump 22 and a purification tank 17 . The outlet of the filling pump 22 is connected to the purification tank 17 for pumping the agent in the water treatment agent storage tank 16 into the purification tank 17 .

[0023] The water pumped from the liquid accumulation pit 2 to the water treatment device 7 by the submersible pump 3 is mixed with the agent pumped out from the water treatment agent storage tank 16 in the purification tank 17 to achieve water purification.

[0024] In this embodiment, the submersible pump 3 and the filling pump 22 are both electrically connected to the control box 25, and the simultaneous on / off control is realized by the control module in the control box 25. Furthermore, a liquid level monitoring device 4 is provided in the effluent pit 2, and the liquid level monitoring device 4 is connected to the control box 25 by a wiring 6, and realizes liquid level linkage control with the submersible pump 3 and the filling pump 22. Preferably, the liquid level monitoring device 4 adopts a float type liquid level controller. In the automatic operation mode, when the water level in the effluent pit 2 is at a high level, the control module connects the power supply of the submersible pump 3 and the filling pump 22, and the submersible pump 3 and the filling pump 22 work at the same time, the accumulated liquid in the square well 1 and the water treatment agent are mixed in the purification box 17, and the water is purified. When the water level in the effluent pit 2 drops to a low level, the control module turns off the power supply of the submersible pump 3 and the filling pump 22, and the submersible pump 3 and the filling pump 22 stop working.

[0025] Preferably, in this embodiment, the filling amount of the water treatment agent can be controlled by selecting the displacement of the filling pump 22 or installing a flow regulating valve on the filling pump outlet pipe 23 to achieve the best use effect of the water treatment agent.

[0026] Further, such as Figure 3 As shown, the purification box 17 is filled with oil-absorbing felt 18, active adsorption particles 19, gravel, filter cloth 20 and other materials in layers. The top of the filler is kept a distance from the water outlet of the submersible pump 3 and the filling pump 22, and the bottom side of the purification box 17 is provided with a through hole 21 connected to the water storage tank 9.

[0027] After the accumulated liquid entering the purification box 17 is mixed with the water treatment agent at the upper part of the purification box 17, a physical / chemical reaction occurs, and the water is preliminarily purified. The water flows downward and flows into the water storage tank 9 through the through hole 21 at the bottom of the purification box 17. In the process of flowing downward, the water comes into contact with multiple layers of materials such as oil-absorbing felt 18, active adsorption particles 19, gravel, filter cloth 20, etc., and is further purified through adsorption and filtration.

[0028] Furthermore, an overflow port 11 is provided on the upper part of the water tank 9, and the opening of the overflow port 11 is lower than the outlet of the submersible pump 3 and the filling pump 22, and a sewage valve 12 is provided at the bottom of the water tank 9. When the liquid level inside the water tank 9 is higher than the overflow port 11, water overflows from the overflow port 11 to ensure that the liquid level in the water tank 9 is always lower than the outlet of the submersible pump 3 and the filling pump 22 in the purification box 17, and the accumulated liquid extracted from the square well 1 can be continuously purified, and when the submersible pump 3 and the filling pump 22 stop working, the water in the water tank 9 will not flow back.

[0029] Furthermore, a purified water pipeline connected to the cleaning machine 26 is provided at the lower part of the water storage tank 9. Figure 4As shown, the cleaning machine 26 is equipped with a cleaning pipe and a water gun 27, and the cleaning machine 26 is driven by the control box 25 connected to the power supply. When the wellhead or gas well site equipment needs to be cleaned, the cleaning machine 26 can be started, and the equipment is cleaned using the cleaning pipe and the water gun 27. The sewage after cleaning is returned to the liquid accumulation pit 2 in the square well 1 again, so that the water is reused. When the water jacket boiler (natural gas production site heating equipment) in the station needs to be supplemented with water, the water jacket boiler can also be supplemented with water through the cleaning machine 26, saving the cost of supplementing water from the outside.

[0030] For production sites without mains electricity access, the system is also equipped with a solar power generation device, including a solar panel 13, a battery storage device 24 and a control box 25. The solar panel 13 bracket 14 is installed on the water treatment device 7, and the battery storage device 24 and the control system are installed inside the water treatment device 7. The entire set of devices can be centrally installed as a skid to reduce the manufacturing, installation and use costs.

[0031] The electrical system of the whole device of the present invention adopts low-voltage DC safety voltage power supply (36V and below, 12V is recommended), which can greatly reduce the safety risk caused by leakage of the device, and there is no need to adjust the voltage when using batteries. At the same time, the solar photovoltaic power generation current can be directly supplied to the storage device 24 for storage and driving the submersible pump 3 and the filling pump 22, which can reduce the cost of adding substation equipment and reduce the failure rate of the power supply system.

[0032] In this embodiment, the top of the water treatment device 7 can also be designed as a fully openable waterproof box cover, and the side of the electric control box 10 for installing the electric storage 24, the control box 25, and the cleaning machine 26 is provided with a side door and a waterproof vent 15. In this way, by opening the waterproof box cover, the water quality of the water storage tank 9 can be sampled and tested, the filling material in the purification box 17 can be replaced, and the water treatment agent can be replenished. By opening the side door of the electric control box 10, the equipment status can be checked and the cleaning pump can be operated.

[0033] Example 2 As an optimization solution, based on Example 1, since most of the square well effluents contain only a small amount of oil, oil absorption and filtration can make the water quality meet the standards. For the treatment of this type of effluent, the water treatment tank can cancel the water treatment agent filling design, thereby reducing equipment manufacturing costs.

[0034] As an optimization solution, if the water treatment agent injection solution is not used, a submersible pump with a built-in float level control can be used. In this way, there is no need to install a separate level control monitoring and control module.

[0035] As an optimization solution, for sites with on-site mains access, mains power supply can be used, which can reduce the investment in solar power supply system equipment.

[0036] As an optimization solution, this system can also be equipped with mature equipment such as liquid level monitoring, motor operation status monitoring, and battery power data detection as needed, and adapted to corresponding information equipment to achieve remote monitoring of the entire system's operating status.

[0037] The application effect of the automatic recovery, purification and reuse system for square well liquid accumulation of the present invention is explained below in combination with actual data.

[0038] It is estimated that if water is transferred by water tanker, each square well needs to be drained more than 10 times a year, with a single cost of more than 10,000 yuan (vehicle transfer fee, water reinjection treatment fee, and labor cost). The price of each set of automatic recovery, purification and reuse system for accumulated liquid in square wells is about 30,000 yuan. It can be used for more than 10 years after a single investment, and the annual operation and maintenance cost is about 5,000 yuan. That is, each set of modified system put into use can save production costs of 92,000 yuan (1×10-3÷10-0.5).

[0039] At present, there are more than 1,000 square wells with liquid accumulation in the study area, and with the development of conventional natural gas, shale gas and tight gas, the number is still increasing. Therefore, this system has high economic value and good application prospects.

[0040] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification or equivalent change made to the above embodiment based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A system for automatically recovering, purifying and reusing liquid in a square well, characterized in that: The invention comprises a water treatment device (7) connected to a liquid accumulation pit (2) at the bottom of a square well (1), wherein a submersible pump (3) is arranged in the liquid accumulation pit (2), and the submersible pump (3) is used to pump the accumulated liquid into the water treatment device (7); the water treatment device (7) comprises a purification box (17) and a water storage tank (9) which are connected to each other, wherein the purification box (17) is connected to the outlet of the submersible pump (3) and is used to purify the accumulated liquid, and the water storage tank (9) is used to store the accumulated liquid after purification; the water storage tank (9) is connected to a cleaning machine (26) to provide cleaning water for the cleaning machine (26), and the cleaning machine (26) and the submersible pump (3) are both connected to a control box (25) for control.

2. The automatic recovery, purification and reuse system for square well liquid accumulation according to claim 1 is characterized in that: The water treatment device (7) further comprises a water treatment agent storage tank (16) and a filling pump (22), wherein the filling pump (22) is used to pump the agent in the water treatment agent storage tank (16) into the purification tank (17) to mix with the accumulated liquid to achieve purification treatment.

3. The automatic recovery, purification and reuse system for square well liquid accumulation according to claim 2 is characterized in that: A liquid level monitoring device (4) is provided in the liquid accumulation pit (2); the liquid level monitoring device (4) is electrically connected to the control box (25) and realizes liquid level linkage control together with the submersible pump (3) and the filling pump (22).

4. The automatic recovery, purification and reuse system for square well liquid accumulation according to claim 2 is characterized in that: The interior of the purification box (17) is filled in layers with oil-absorbing felt (18), active adsorption particles (19), gravel, and filter cloth (20), and the top of the filling material is spaced a distance from the submersible pump (3) and the filling pump (22).

5. The automatic recovery, purification and reuse system for square well liquid accumulation according to claim 2 is characterized in that: A through hole (21) communicating with the water storage tank (9) is provided on the bottom side of the purification box (17).

6. The automatic recovery, purification and reuse system for square well liquid accumulation according to claim 2 is characterized in that: An overflow port (11) is provided at the upper part of the water storage tank (9), the overflow port (11) has an opening lower than the outlets of the submersible pump (3) and the filling pump (22), and a drain valve (12) is provided at the bottom of the water storage tank (9).

7. The automatic recovery, purification and reuse system for square well liquid accumulation according to claim 1 is characterized in that: The cleaning machine (26) is equipped with a cleaning pipe and a water gun (27). The cleaning machine (26) is connected to a power supply through the control box (25) and driven, and the start and stop of the cleaning machine (26) is manually controlled by a control knob on the panel of the control box (25).

8. The automatic recovery, purification and reuse system for square well liquid accumulation according to claim 1 is characterized in that: The solar power supply system also includes a solar panel (13), a storage device (24), and a bracket (14). The solar panel (13) is supported by the bracket (14), and the bracket (14) is installed on the water treatment device (7). The solar panel (13) is connected to the storage device (24), and the storage device (24) is connected to the control box (25).

9. The automatic recovery, purification and reuse system for square well liquid accumulation according to claim 8, characterized in that: A fully openable waterproof box cover is provided on the top of the water treatment device (7), and the side of the electric control box (10) on which the electric storage device (24), the control box (25), and the cleaning machine (26) are installed is designed as a side-opening door, and ventilation holes (15) capable of preventing dust and water are provided on both sides of the electric control box (10) or on the side-opening door.

10. The automatic recovery, purification and reuse system for square well liquid accumulation according to claim 2, characterized in that: The filling pump outlet pipe (23) is provided with a flow regulating valve for controlling the filling amount of the water treatment agent.

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