A method for oil-water separation for gas field water treatment

Abstract

The application discloses an oil-water separation method for gas field water treatment and relates to the technical field of gas well safety prevention. The gas field water containing oil and water is continuously pumped into a closed container, the water liquid in the closed container sinks, the oil liquid floats, the height of the demarcation line between the water liquid and the oil liquid is monitored, and the water liquid is discharged through a water outlet below the closed container after the height of the demarcation line between the water liquid and the oil liquid reaches a set height. Meanwhile, the liquid level of the oil liquid above is monitored, and the oil liquid overflows from the closed container when the liquid level of the oil liquid exceeds a preset height, so that oil-water separation is realized. The oil-water separation method utilizes a physical method to separate oil and water, does not need to use a separation screen to separate oil and water, can be continuously performed, has low oil-water separation cost and high oil-water separation efficiency.

Description

Technical Field

[0001] This invention belongs to the field of gas well safety protection technology, and more specifically relates to an oil-water separation method for gas field water treatment. Background Technology

[0002] Wastewater generated during natural gas well production includes well water, formation water, drilling fluid, and compressor sludge produced during drilling. This wastewater often contains large amounts of flammable oil components, and improper handling during storage, transfer, and discharge can pose significant safety hazards.

[0003] Currently, gas well water reinjection sites typically handle floating oil by manually dredging periodically for centralized processing. However, this manual dredging method carries significant operational safety risks and suffers from low efficiency and the inability to achieve real-time dredging. Therefore, a more convenient, faster, and safer method for oil-water separation is needed.

[0004] For example, the published text of the invention patent application entitled "Oil-Water Separation Device and Manufacturing Method Thereof," published on May 6, 2022, with publication number CN114436366A, discloses an oil-water separation device including a first separation screen. The first separation screen includes a first mounting groove, a second mounting groove, and a first separation screen. The first mounting groove is located within the second mounting groove, and a first cavity is formed between the first and second mounting grooves. The first separation screen is located within the first cavity. The bottom of the first mounting groove has a first through hole. The bottom of the second mounting groove has a second through hole opposite to the first through hole. The first separation screen has a plurality of spaced-apart first separation holes. The first separation holes are filled with titanium dioxide particles and a composite layer of polyethylene glycol and dopamine. Due to the superhydrophilicity and underwater superoleophobicity of the titanium dioxide particles and the polyethylene glycol and dopamine composite layer, the oil-water separation device can achieve a good filtration effect on gas well water, improving the oil-water separation effect and enabling the gas well water to meet reinjection requirements.

[0005] The above-mentioned oil-water separation device has a relatively complex structure and requires the use of a separation screen to achieve separation. When the separation screen is blocked, it needs to be replaced. Replacing the separation screen requires stopping the machine. On the one hand, the consumption of the separation screen increases the cost of oil-water separation, and on the other hand, stopping the machine to replace the separation screen also affects the oil-water separation efficiency. Summary of the Invention

[0006] To overcome the defects and shortcomings of the existing technology, this invention provides an oil-water separation method for gas field water treatment. The purpose of this invention is to solve the problems of complex existing oil-water separation processes, increased costs due to the use of separation screens, and reduced efficiency due to downtime for screen replacement. The oil-water separation method of this invention utilizes the difference in density between oil and water, with oil suspended on the water surface, to achieve oil-water separation. Specifically, gas field water containing both oil and water is continuously pumped into a sealed container. Within the sealed container, the water sinks while the oil rises. The height of the water-oil boundary line is monitored. Once the boundary line reaches a set height, the outlet at the bottom of the sealed container is opened to drain the water. Simultaneously, the oil level above is monitored. When the oil level exceeds a preset height, the oil overflows from the sealed container, achieving oil-water separation. The oil-water separation method of the present invention uses physical means to separate oil and water, without the need for a separation screen, can be carried out continuously, has low oil-water separation cost, and high oil-water separation efficiency.

[0007] To address the problems existing in the prior art, the present invention is achieved through the following technical solution.

[0008] This invention provides an oil-water separation method for gas field water treatment, specifically, the oil-water separation method is as follows:

[0009] Gas field water containing both oil and water is continuously pumped into the separation chamber of a sealed container.

[0010] The gas field water pumped into the sealed container is separated in this chamber, where the water sinks and the oil floats.

[0011] When the boundary between oil and water is lower than the set first boundary height, the outlet at the bottom of the sealed container is closed; when the boundary between water and oil is higher than the set first boundary height, the outlet at the bottom of the sealed container is opened to discharge the water; the oil is discharged from the top of the separation chamber.

[0012] In a further preferred embodiment, a separation baffle is used to divide the separation chamber into a bottom-connected settling chamber and a liquid inlet chamber, with the upper parts of the settling chamber and the liquid inlet chamber connected by a perforated structure in the separation baffle. Gas field water containing oil and water is continuously pumped into the liquid inlet chamber, and the height of the boundary line between the oil and water in the settling chamber is monitored. When the boundary line between the oil and water in the settling chamber is higher than a set first boundary line, the outlet at the bottom of the separation chamber is opened to discharge the water.

[0013] In a further preferred embodiment, the height of the oil-water boundary line in the settling chamber is monitored by setting a control float inside the settling chamber. The density of the control float is greater than the density of the oil to be separated but less than the density of the water. The control float is connected to the outlet plug at the bottom of the separation chamber. When the control float rises to the set first boundary line height, it drives the outlet plug to open the outlet. As the water is discharged, the oil-water boundary line in the settling chamber drops. When the oil-water boundary line is lower than the first boundary line height, the control float descends and drives the outlet plug to block the outlet.

[0014] More preferably, during the process of controlling the float to rise or fall with the boundary between oil and water, the movement of the float in the horizontal direction is restricted.

[0015] More preferably, the horizontal movement of the control float is restricted and controlled by a connecting rod installed in the separation chamber. The connecting rod includes a vertical section and a horizontal section. The control float is connected to the upper part of the vertical section, one end of the horizontal section is connected to the lower part of the vertical section, and the other end is hinged to the inner wall of the separation chamber. The water outlet plug is fixedly connected downward below the horizontal section.

[0016] Furthermore, the vertical and horizontal segments are rotatably connected.

[0017] The first dividing line height is set by adjusting the height of the buoy in the vertical section.

[0018] A further preferred embodiment involves discharging the gas from the gas field water before continuously pumping the gas field water containing both oil and water into the separation chamber.

[0019] In a further preferred embodiment, the gas in the gas field water is discharged by setting a transition box on the separation chamber. The lower part of the transition box has several leakage holes. One end of the transition box is connected to the outlet end of the pipeline that pumps the gas field water, and the other end is connected to the outside of the sealed container by a gas outlet pipe. The gas field water falls into the separation chamber through the leakage holes, and the gas in the gas field water is discharged into the sealed container through the gas outlet pipe.

[0020] Even more preferably, the end of the vent pipe extending outside the sealed container is bent downwards to prevent foreign matter from entering through the vent pipe.

[0021] More preferably, several traction wires hanging down to the bottom of the box are fixedly installed on the upper side wall of the inner cavity of the transition box.

[0022] In a further preferred embodiment, when the oil level exceeds the preset oil height, it overflows into the oil storage chamber on one side of the separation chamber.

[0023] More preferably, the preset oil level is set by controlling the height of the overflow baffle between the oil storage chamber and the separation chamber. When the oil level in the separation chamber is higher than the height of the overflow baffle, the oil overflows from the overflow baffle into the oil storage chamber.

[0024] Further preferably, when the oil level in the oil storage chamber is higher than the set height, the oil outlet at the bottom of the oil storage chamber is opened to discharge the oil.

[0025] In a further preferred embodiment, the oil level in the oil storage chamber is detected by a liquid level detection sensor installed in the oil storage chamber. When the liquid level detection sensor detects that the oil level in the oil storage chamber is higher than the set height, the oil outlet at the bottom of the oil storage chamber is opened to discharge the oil.

[0026] Even more preferably, the oil outlet is connected to an oil outlet pipe, and an oil pump is connected to the oil outlet pipe.

[0027] In an even more preferred embodiment, the outlet is connected to a return pipe, and the water discharged from the outlet flows back to the gas field pool through the return pipe.

[0028] In a further preferred embodiment, when the quality of the oil in the oil storage chamber is poor, the poor-quality oil is returned to the gas field water pool.

[0029] In a further preferred embodiment, the oil outlet pipe connected to the oil outlet is connected to the return pipe connected to the water outlet. When the oil quality in the oil outlet chamber is poor, the switching of the solenoid valves on the oil outlet pipe and the return pipe is controlled to return the oil in the oil storage chamber to the gas field water pool through the return pipe.

[0030] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0031] 1. This invention utilizes the difference in specific gravity between oil and water to achieve natural stratification, causing oil to overflow from the top and water to leak from the bottom. Control is achieved by monitoring the boundary between the oil and water. It has the advantages of simple oil-water separation process, reliable separation, good stability, can be carried out in a closed container, and good safety.

[0032] 2. This invention monitors the oil-water boundary to keep the water level in the separation chamber within a certain range, preventing water from being discharged before complete oil-water separation and thus avoiding the discharge of water containing oil. The height of the oil-water boundary provides sufficient separation time, and a certain amount of water is discharged when the boundary exceeds the set height, keeping the water volume within the set range. Oil gradually accumulates in the separation chamber, overflowing into the oil storage chamber when it reaches the set height. This accumulation process further ensures the oil-water separation effect and prevents incomplete separation.

[0033] 3. This invention uses a partition to divide the separation chamber into a bottom-connected settling chamber and an inlet chamber. This avoids the impact of continuously entering gas field water on the stability of oil-water separation, ensures the stability of oil overflow after the set oil level in the settling chamber, and also ensures the stability of the oil-water boundary monitoring. Using a porous or mesh structure plate as the partition reduces the impact of the descending oil-water flow in the inlet chamber on the control float in the settling chamber. Furthermore, the partition allows communication between the settling chamber and the inlet chamber through its perforations, ensuring that the oil levels in both chambers are the same. This prevents the accumulation of oil in the inlet chamber as bottom water is discharged, which could obstruct the entry of gas field water and facilitate the flow of oil from the inlet chamber to the settling chamber.

[0034] 4. This invention uses a control float to monitor the oil-water boundary line. This physical monitoring method offers better stability compared to methods like liquid level sensors, avoiding malfunctions caused by boundary line fluctuations in electronic monitoring. The control float has a density less than the oil to be separated but greater than the water. It sinks into the oil and floats on top of the water, always remaining at the oil-water boundary line. It rises as the boundary line rises and falls as it falls, improving the stability of the oil-water boundary line monitoring.

[0035] 5. This invention utilizes a control float to control the opening and closing of the water outlet. To prevent the outlet from opening accidentally due to horizontal movement of the control float, it is necessary to restrict its horizontal movement so that the control float only rises or falls with the oil-water boundary line. This invention uses a simple connecting rod to restrict the horizontal movement of the control float. Furthermore, by setting the height of the control float on the vertical section of the connecting rod, the height setting of the oil-water boundary line can also be changed. The structure is simple, easy to implement, and highly stable.

[0036] 6. This invention discharges gas from the water in the gas field, which can prevent air mixed in the liquid from entering the sealed container, causing the gas pressure inside the sealed container to rise and affect safety, thus improving the explosion-proof safety performance of the sealed container.

[0037] 7. This invention discharges gas from gas field water by setting up a transition box. The structure is simple, easy to implement, and low in cost. The outlet pipe is bent downwards to better prevent impurities from entering through the outlet pipe. Several traction wires are also fixedly installed on the upper side wall of the transition box cavity, hanging down to the bottom of the box. This is because the oil component has high viscosity; under the traction force generated by the leakage through the drain hole, smaller air bubbles trapped in the oil are difficult to overflow within a short transition time. Therefore, the traction wires help air bubbles in the oil adhere to and converge on them, and then overflow upwards to the upper end of the transition box, further improving the gas-liquid separation effect.

[0038] 8. The present invention sets an overflow baffle to divide the sealed container into an oil storage chamber and a separation chamber. The setting of the oil storage chamber ensures the stability of the oil overflowing from the overflow baffle, and at the same time ensures the stability of the control float operation.

[0039] 9. By installing a liquid level detection sensor in the oil storage chamber and an oil discharge pump, the discharge of oil from the storage chamber is accelerated, and automatic control can be achieved. Poor-quality oil is returned to the gas field water tank for further oil separation to improve the quality of the separated oil. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of an embodiment of the oil-water separation method for gas field water treatment according to the present invention;

[0041] Reference numerals: 1. Housing, 2. Separation chamber, 3. Oil storage chamber, 4. Water outlet, 5. Separation baffle, 6. Settling chamber, 7. Liquid inlet chamber, 8. Control float, 9. Water outlet plug, 10. Connecting rod, 11. Vertical section, 12. Horizontal section, 13. Transition box, 14. Leakage hole, 15. Air outlet pipe, 16. Overflow baffle, 17. Oil outlet, 18. Liquid level detection sensor, 19. Oil outlet pipe, 20. Oil outlet pump, 21. Return pipe, 22. Control center, 23. Battery, 24. Control room, 25. Pump room, 26. Suction pump, 27. Delivery pipe. Detailed Implementation

[0042] The technical solutions in 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 some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Example 1

[0044] As a preferred embodiment of the present invention, this embodiment discloses an oil-water separation method for gas field water treatment. Specifically, the oil-water separation method is as follows:

[0045] Gas field water containing both oil and water is continuously pumped into the separation chamber 2 of a sealed container.

[0046] The gas field water pumped into the sealed container is in the separation chamber 2, where the water sinks and the oil floats.

[0047] When the water-oil boundary is lower than the set first boundary height, the outlet 4 at the bottom of the sealed container is closed; when the water-oil boundary is higher than the set first boundary height, the outlet 4 at the bottom of the sealed container is opened to discharge the water; the oil is discharged from the top into the separation chamber 2.

[0048] In this embodiment, the oil and water are separated by natural stratification due to their different specific gravities, causing the oil to overflow from the top and the water to leak from the bottom. The separation is controlled by monitoring the boundary between the oil and water. This method has the advantages of simple oil-water separation process, reliable separation, good stability, and the ability to be carried out in a closed container, as well as good safety.

[0049] In this embodiment, by monitoring the oil-water boundary line, the water in the separation chamber 2 is always controlled within a certain height range. This avoids the situation where water is discharged before oil-water separation is complete, resulting in the discharged water containing a certain amount of oil. The height setting of the oil-water boundary line provides separation time for the oil and water. When the oil-water boundary line is higher than the set height, a certain amount of water is discharged, keeping the water volume within the set range. The oil gradually accumulates in the separation chamber 2. When the oil accumulates to the set height, it is discharged. The oil accumulation process further improves the quality of the separated oil and ensures the stability of oil-water separation.

[0050] In one embodiment of this invention, when the oil level exceeds a preset oil height, it overflows into the oil storage chamber 3 on one side of the separation chamber 2. This overflow method ensures the stability of the oil and further guarantees effective oil-water separation, preventing incomplete separation.

[0051] As one implementation method of this embodiment, the oil-water boundary line can be monitored using electronic monitoring sensors, such as setting up a liquid level sensor connected to relevant equipment, thereby realizing the monitoring of the oil-water boundary line and the control of water discharge.

[0052] Example 2

[0053] As another preferred embodiment of the present invention, this embodiment is a further detailed supplement and explanation of the technical solution of the present invention based on the above embodiment 1. In this embodiment, a separation partition 5 is used to divide the separation chamber 2 into a bottom-connected settling chamber 6 and a liquid inlet chamber 7. The upper parts of the settling chamber 6 and the liquid inlet chamber 7 are connected through the perforated structure of the separation partition 5. Gas field water containing oil and water is continuously pumped into the liquid inlet chamber 7. The height of the boundary line between the oil and water in the settling chamber 6 is monitored. When the boundary line between the oil and water in the settling chamber 6 is higher than the height of a set first boundary line, the outlet 4 at the bottom of the separation chamber 2 is opened to discharge the water.

[0054] The separation chamber 2 is divided into a bottom-connected settling chamber 6 and a liquid inlet chamber 7 by the separation baffle 5, which avoids the impact of continuously newly entering gas field water in the separation chamber 2 on the stability of oil-water separation, ensures the stability of oil overflow after the oil level in the set set height in the settling chamber 6, and also ensures the stability of monitoring the oil-water boundary line.

[0055] Further, please refer to the appendix to the instruction manual. Figure 1 As shown, the height of the oil-water boundary in the settling chamber 6 is monitored by setting a control float 8 inside the settling chamber 6. The density of the control float 8 is greater than the density of the oil to be separated but less than the density of the water. The control float 8 is connected to the outlet plug 9 at the bottom outlet 4 of the separation chamber 2. When the control float 8 rises to the set first boundary height, it drives the outlet plug 9 to open the outlet 4. As the water is discharged, the oil-water boundary in the settling chamber 6 drops. When the oil-water boundary is lower than the first boundary height, the control float 8 drops and drives the outlet plug 9 to block the outlet 4.

[0056] This embodiment uses a control float 8 to monitor the oil-water boundary. This physical monitoring method offers better stability compared to methods like liquid level sensors, avoiding malfunctions caused by boundary fluctuations in electronic monitoring. The control float 8 has a density less than the oil to be separated but greater than the water. It sinks into the oil and floats on top of the water, ensuring it remains at the oil-water boundary. It rises as the boundary rises and falls as it falls, thus improving the stability of the oil-water boundary monitoring.

[0057] Refer to the instruction manual appendix Figure 1 As shown, in a specific embodiment of the oil-water separation method of the present invention, a box 1 is used as a sealed container. A separation chamber 2 is set inside the box 1. An oil storage chamber 3 is set on one side of the separation chamber 2, separated by an overflow baffle 16. The upper end of the separation chamber 2 is connected to the outlet end of the pipeline 27 for pumping gas field water. A water outlet 4 is set on the bottom surface of the lower end of the separation chamber 2. A return pipeline 21 is set on the water outlet 4 and connected to the gas field water pool. A water outlet control switch is set at the water outlet 4. The water outlet control switch includes a water outlet 4 plug located at the water outlet 4 and a control float 8 located in the middle of the separation chamber 2. The density of the control float 8 is greater than the density of the oil to be separated but less than the density of the water. The control float 8 and the water outlet 4 plug are connected by a connecting rod 10. A horizontal movement limiting structure is also provided to limit the horizontal movement of the control float 8. Using the box 1 as a sealed container, gas field water containing oil and water is continuously pumped into the separation chamber 2 to achieve oil-water separation.

[0058] Thus, when using the aforementioned oil-water separation and storage device, a mixture of oil and water is input through the conveying pipe 27. The mixture enters the separation chamber 2 and settles, with the oil rising and the water sinking. Before the mixture reaches the control float 8, the outlet 4 plug is blocked by its own weight. When the mixture reaches the control float 8, the control float 8 is initially submerged in the upper layer of oil. Because its density is greater than that of the oil, the control float 8 will not rise, and the outlet 4 remains closed. When the upper layer of oil rises to the overflow baffle 16, it overflows through the overflow baffle 16 into the oil storage chamber 3 for storage and recycling. When the water component in the lower part of the separation chamber 2 gradually accumulates and reaches and exceeds the position of the control float 8, because the density of the control float 8 is less than that of the water, the control float 8 rises with the water height, causing the plug of the outlet 4 to open the outlet 4, and the water flows out from the outlet 4. The height of the water part drops, and because the density of the control float 8 is greater than that of the oil, the control float 8 will fall with the water part, causing the plug of the outlet 4 to close the outlet 4. This process repeats, achieving automatic water discharge from the outlet 4, and ensuring that the area above the control float 8 in the middle of the separation chamber 2 is a stable oil component and the area below is a stable water component, thus better achieving automatic oil-water separation; it also has the characteristics of good explosion-proof safety.

[0059] More preferably, during the process of controlling the float 8 to rise or fall with the boundary between oil and water, the movement of the float 8 in the horizontal direction is restricted.

[0060] As an example, limiting the horizontal movement of the control float 8 is achieved through a connecting rod 10 installed in the separation chamber 2. The connecting rod 10 includes a vertical section 11 and a horizontal section 12. The control float 8 is connected to the upper part of the vertical section 11, and one end of the horizontal section 12 is connected to the lower part of the vertical section 11, while the other end is hinged to the inner wall of the separation chamber 2. The outlet plug 9 is fixedly connected downwards below the horizontal section 12. This not only achieves horizontal movement limitation of the control float 8 with a simple structure, but the horizontal section 12 also forms a lever structure, amplifying the buoyancy of the control float 8's control effect on opening the outlet plug 4 upwards, thus improving the reliability and stability of the control.

[0061] Furthermore, the vertical segment 11 and the horizontal segment 12 are rotatably connected. This prevents the vertical segment 11 from tilting due to the rotation of the horizontal segment 12, thus avoiding the transmission of influence and better ensuring the stability and reliability of the control.

[0062] The height of the first dividing line is set by adjusting the height of the control float 8 on the vertical section 11. Specifically, the vertical section 11 is provided with external threads, and the control float 8 has a threaded hole that is threaded through it and screwed onto the vertical section 11. In this way, when needed, the height position of the control float 8 on the vertical section 11 can be easily adjusted by rotating it, thus better ensuring the stability of liquid and water discharge.

[0063] Furthermore, a locking nut is threaded onto the vertical section 11 above the control float 8. This allows the control float 8 to be tightened by the locking nut, achieving a locking effect.

[0064] Example 3

[0065] As another preferred embodiment of the present invention, this embodiment is a further detailed supplement and explanation of the technical solution of the present invention based on the above embodiment 1 or embodiment 2.

[0066] In this embodiment, before continuously pumping the gas field water containing oil and water into the separation chamber 2, the gas in the gas field water is discharged.

[0067] The specific implementation plan is as follows: refer to the attached instruction manual. Figure 1 As shown, the gas discharged from the gas field water is achieved by installing a transition box 13 on the separation chamber 2. The lower part of the transition box 13 has several leakage holes 14. One end of the transition box 13 is connected to the outlet end of the gas field water delivery pipe 27, and the other end has an outlet pipe 15 connected to the outside of a sealed container. The gas field water falls into the separation chamber 2 through the leakage holes 14, and the gas in the gas field water is discharged from the sealed container through the outlet pipe 15. In this way, the delivery pipe 27 first delivers the mixture to the transition box 13, where gas-liquid separation is achieved. The liquid portion leaks from the leakage holes 14 at the bottom of the transition box 13 into the separation chamber 2, while the gas portion gathers above the transition box 13 and is discharged through the outlet pipe 15. This prevents air trapped in the mixture from entering the housing 1, which could cause an increase in pressure within the sealed housing 1 and affect safety. This also improves the explosion-proof safety performance of the housing 1.

[0068] Furthermore, the outlet of the vent pipe 15 is bent downwards. This better prevents debris from entering through the vent pipe 15.

[0069] Furthermore, several traction wires are fixedly installed on the upper side wall of the inner cavity of the transition box 13, hanging down to the bottom of the box. This is because the oil has high viscosity, and under the traction force generated by the leakage through the leakage hole 14, some smaller air bubbles trapped in the oil are difficult to overflow in a short transition time. Therefore, the traction wires help the air bubbles in the oil to adhere to and gather on them and overflow upwards to the upper end of the transition box 13, further improving the gas-liquid separation effect.

[0070] Example 4

[0071] As another preferred embodiment of the present invention, this embodiment is a further detailed supplement and explanation of the technical solution of the present invention based on the above embodiment 1, embodiment 2 or embodiment 3.

[0072] In this embodiment, when the oil level exceeds the preset oil height, it overflows into the oil storage chamber 3 on one side of the separation chamber 2. An overflow baffle 16 divides the sealed container into the oil storage chamber 3 and the separation chamber 2. The oil storage chamber 3 ensures the stability of the oil overflowing from the overflow baffle 16, while also ensuring the stability of the control float 8. When the oil accumulates to the set height, it overflows into the oil storage chamber 3. This accumulation process further ensures the oil-water separation effect and avoids incomplete oil-water separation.

[0073] More preferably, the preset oil level is set by controlling the height of the overflow baffle 16 between the oil storage chamber 3 and the separation chamber 2. When the oil level in the separation chamber 2 is higher than the height of the overflow baffle 16, the oil overflows from the overflow baffle 16 into the oil storage chamber 3. When the oil level in the oil storage chamber 3 is higher than the set height, the oil outlet 17 at the bottom of the oil storage chamber 3 is opened to discharge the oil.

[0074] More preferably, the oil level in the oil storage chamber 3 is detected by a liquid level detection sensor 18 installed in the oil storage chamber 3. When the liquid level detection sensor 18 detects that the oil level in the oil storage chamber 3 is higher than the set height, it opens the oil outlet 17 at the bottom of the oil storage chamber 3 to discharge the oil.

[0075] In one embodiment of this invention, the oil outlet 17 is connected to the oil outlet pipe 19, and the oil outlet pump 20 is connected to the oil outlet pipe 19. The water outlet 4 is connected to the return pipe 21, and the water discharged from the water outlet 4 flows back to the gas field water tank through the return pipe 21. When the oil quality in the oil storage chamber 3 is poor, the poor-quality oil is returned to the gas field water tank. Specifically, the oil outlet pipe 19 connected to the oil outlet 17 is connected to the return pipe 21 connected to the water outlet 4. When the oil quality in the oil outlet chamber is poor, the switching of the solenoid valves on the oil outlet pipe 19 and the return pipe 21 is controlled, and the oil in the oil storage chamber 3 is returned to the gas field water tank through the return pipe 21.

[0076] As a specific implementation structure of this embodiment, please refer to the appendix to the specification. Figure 1 As shown, a pump chamber 25 is also installed inside the housing 1 below the separation chamber 2 and the oil storage chamber 3. An oil outlet pump 20 is installed inside the pump chamber 25. An oil outlet 17 is located at the bottom of the oil storage chamber 3, and an oil outlet pipe 19 connects to the outside of the housing 1. The oil outlet pump 20 is mounted on the oil outlet pipe 19. This facilitates the extraction of oil stored in the oil storage chamber 3 by the oil outlet pump 20. A suction pump 26 on the delivery pipe 27 is installed inside the pump chamber 25.

[0077] A liquid level detection sensor 18 is also installed in the oil storage chamber 3. The liquid level detection sensor 18 is connected to the control center 22, and the control center 22 is connected to the oil pump 20. In this way, the liquid level detection sensor 18 can detect the oil level and control the oil pump 20 to extract oil when the preset height is reached, thus realizing automatic control.

[0078] A connecting pipe is also provided between the oil outlet pipe 19 and the return pipe 21 in the pump chamber 25. An electrically controlled valve is installed between the oil outlet pipe 19, the return pipe 21, and the connecting pipe. The electrically controlled valves are connected to the control center 22. In this way, the switching can be controlled by the electrically controlled valves. When the oil quality in the oil storage chamber 3 is poor, it can also be returned to the gas field water pool through the return pipe 21.

[0079] Furthermore, a control room 24 is also provided inside the housing 1 above the separation chamber 2 and the oil storage chamber 3. The control room 24 contains a control center 22 and a battery 23.

Claims

1. An oil-water separation method for gas field water treatment, characterized in that: The specific method for oil-water separation is as follows: Gas field water containing oil and water is continuously pumped into the separation chamber (2) of a closed container; The gas field water that is pumped into the sealed container is in the separation chamber (2), where the water sinks and the oil floats. When the boundary between oil and water is lower than the set first boundary height, the outlet (4) at the bottom of the sealed container is closed; when the boundary between water and oil is higher than the set first boundary height, the outlet (4) at the bottom of the sealed container is opened to discharge the water; the oil is discharged from the top into the separation chamber (2). The separation chamber (2) is divided into a bottom-connected settling chamber (6) and a liquid inlet chamber (7) by a separation partition (5). The upper parts of the settling chamber (6) and the liquid inlet chamber (7) are connected by a hole structure on the separation partition (5). Gas field water containing oil and water is continuously pumped into the liquid inlet chamber (7). The height of the boundary line between oil and water in the settling chamber (6) is monitored. When the boundary line between oil and water in the settling chamber (6) is higher than the height of the first boundary line, the outlet (4) at the bottom of the separation chamber (2) is opened to discharge the water. The height of the oil-water boundary in the settling chamber (6) is monitored by setting a control float (8) in the settling chamber (6). The density of the control float (8) is greater than the density of the oil to be separated but less than the density of the water. The control float (8) is connected to the outlet plug (9) at the bottom outlet (4) of the separation chamber (2). When the control float (8) rises to the set first boundary height, it drives the outlet plug (9) to open the outlet (4). As the water is discharged, the boundary between the oil and water in the settling chamber (6) drops. When the boundary between the oil and water is lower than the first boundary height, the control float (8) drops and drives the outlet plug (9) to block the outlet (4). When the oil level exceeds the preset oil height, it overflows into the oil storage chamber (3) on one side of the separation chamber (2). The preset oil height is set by controlling the height of the overflow baffle (16) between the oil storage chamber (3) and the separation chamber (2). When the oil level in the separation chamber (2) is higher than the height of the overflow baffle (16), the oil overflows from the overflow baffle (16) into the oil storage chamber (3).

2. The oil-water separation method for gas field water treatment as described in claim 1, characterized in that: During the process of controlling the float (8) to rise or fall with the boundary between oil and water, the movement of the float (8) in the horizontal direction is restricted.

3. The oil-water separation method for gas field water treatment as described in claim 2, characterized in that: The horizontal movement of the control float (8) is restricted by a connecting rod (10) provided in the separation chamber (2). The connecting rod (10) includes a vertical section (11) and a horizontal section (12). The control float (8) is connected to the upper part of the vertical section (11), and one end of the horizontal section (12) is connected to the lower part of the vertical section (11), while the other end is hinged to the inner wall of the separation chamber (2). The outlet plug (9) is fixedly connected downward below the horizontal section (12).

4. The oil-water separation method for gas field water treatment as described in claim 3, characterized in that: The vertical segment (11) and the horizontal segment (12) are rotatably connected.

5. An oil-water separation method for gas field water treatment as described in claim 3 or 4, characterized in that: The height of the first dividing line is set by setting the height of the control float (8) on the vertical section (11).

6. The oil-water separation method for gas field water treatment as described in any one of claims 1-4, characterized in that: Before continuously pumping the gas field water containing oil and water into the separation chamber (2), the gas in the gas field water is discharged.

7. The oil-water separation method for gas field water treatment as described in claim 6, characterized in that: Gas is discharged from the gas field water by setting a transition box (13) on the separation chamber (2). Several leakage holes (14) are opened in the lower part of the transition box (13). One end of the transition box (13) is connected to the outlet end of the pipeline for pumping gas field water, and the other end is connected to the outside of the sealed container by setting an outlet pipe (15). The gas field water falls into the separation chamber (2) through the leakage holes (14), and the gas in the gas field water is discharged from the sealed container through the outlet pipe (15).

8. The oil-water separation method for gas field water treatment as described in claim 7, characterized in that: The vent pipe (15) extends out of the sealed container and is bent downwards at one end.

9. The oil-water separation method for gas field water treatment as described in claim 7, characterized in that: Several traction wires that hang down to the bottom of the box are fixedly installed on the upper side wall of the inner cavity of the transition box (13).

10. An oil-water separation method for gas field water treatment as described in any one of claims 1-4, characterized in that: When the oil level in the oil storage chamber (3) is higher than the set height, the oil outlet (17) at the bottom of the oil storage chamber (3) is opened to discharge the oil.

11. The oil-water separation method for gas field water treatment as described in claim 10, characterized in that: The oil level in the oil storage chamber (3) is detected by a liquid level detection sensor (18) installed in the oil storage chamber (3). When the liquid level detection sensor (18) detects that the oil level in the oil storage chamber (3) is higher than the set height, the oil outlet (17) at the bottom of the oil storage chamber (3) is opened to discharge the oil.

12. The oil-water separation method for gas field water treatment as described in claim 10, characterized in that: The oil outlet (17) is connected to the oil outlet pipe (19), and the oil outlet pump (20) is connected to the oil outlet pipe (19).

13. An oil-water separation method for gas field water treatment as described in any one of claims 1-4, characterized in that: The outlet (4) is connected to the return pipe (21), and the water discharged from the outlet (4) flows back to the gas field pool through the return pipe (21).

14. The oil-water separation method for gas field water treatment as described in claim 10, characterized in that: When the quality of the oil in the oil storage chamber (3) is poor, the poor quality oil is returned to the gas field water pool.

15. The oil-water separation method for gas field water treatment as described in claim 14, characterized in that: Connect the oil outlet (17) to the oil outlet pipe (19) and the water outlet (4) to the return pipe (21). When the oil quality in the oil outlet chamber is poor, control the switching of the solenoid valves on the oil outlet pipe (19) and the return pipe (21) to return the oil in the oil storage chamber (3) to the gas field water pool through the return pipe (21).

Images