Emulsion layer treatment system and method in electric desalting tank

Abstract

The invention provides a system and a method for treating an emulsion layer in an electric desalting tank, and belongs to the technical field of oil refining and chemical engineering. The system comprises a floating oil pumping device and a coupling demulsification device which are arranged in an electric desalting tank in a lifting manner, the two ends of the floating oil pumping device are connected with oil inlets of the oil discharging pipes through hoses respectively. The coupling demulsification device is connected with an oil outlet of the oil discharge pipe and is connected with an oil inlet of the electric desalting tank through an oil return pipeline. As the floating oil pumping device is arranged in the electric desalting tank in a liftable manner, the floating oil pumping device can be changed according to the position of the emulsion layer in the electric desalting tank, so that the floating oil pumping device can accurately pump the stubborn emulsion layer in the electric desalting tank, and the emulsion pumped from the floating oil pumping device enters the coupling demulsification device for demulsification; and the demulsified crude oil is reinjected into the electric desalting tank through an oil return pipeline, so that the resource utilization of the emulsion is realized.

Description

Technical Field

[0001] This invention belongs to the field of oil refining and chemical technology, specifically relating to a system and method for treating the emulsion layer inside an electrostatic desalting tank. Background Technology

[0002] As domestic oilfields generally enter the tertiary recovery stage, the properties of crude oil are becoming increasingly complex, and the quality of oil products is becoming heavier and of lower quality. At the same time, due to the addition of various additives and the influence of factors such as throttling and vibration during crude oil storage and transportation, the degree of crude oil emulsification is becoming higher and higher. After crude oil and water are mixed in a mixer, they enter the electrostatic desalting tank, where oil and water are separated under the action of an electric field. An emulsion layer composed of emulsion is formed at the oil-water interface. Especially when processing heavy, high-viscosity, high-salt, and high-acid-value crude oil, the emulsion layer in the tank will become thicker and thicker. When the emulsion layer becomes thick enough, it will affect the stable operation of the electrostatic desalting unit, leading to problems such as reduced crude oil desalting and dehydration efficiency and substandard salt content of crude oil after desalting. In severe cases, it may cause difficulties in power supply or short circuits in the high-voltage electric field in a short period of time, thus paralyzing the entire electrostatic desalting unit.

[0003] When the emulsion layer thickens on-site, the only current solution is to adjust operating conditions to improve the emulsion to some extent. Once a certain threshold is reached, maintenance of the electro-desalting unit is required to decompose and remove the emulsion layer, or high-pressure filling and cleaning can be performed inside during shutdown maintenance. Both of these methods are not only cumbersome but also require unit shutdown, significantly impacting the efficiency of the crude oil processing system. Furthermore, the extracted emulsion cannot be treated efficiently and environmentally.

[0004] Currently, the main solutions proposed in China to address the difficulty in handling the emulsion layer inside electrostatic desalting tanks are to physically disrupt the stable state of the emulsion layer to achieve demulsification. These solutions include modifications to the electrostatic desalting tank itself and external equipment treatment. For example, Chinese patent publication CN219839660U discloses a mechanical agitation device for breaking down stubborn emulsion layers inside heavy crude oil electrostatic desalting tanks. The electrostatic desalting tank is equipped with several demulsification mechanisms, including an internal demulsification mechanism and an external drive mechanism. The internal demulsification mechanism includes a rotating mechanical shaft and a demulsification structural unit. Through the mechanical agitation demulsification mechanism inside the electrostatic desalting tank, the emulsion layer inside the tank is broken down. Furthermore, a vibrator drives the rotating shear arm on the internal demulsification mechanism to vibrate, ensuring the high efficiency and stability of the electrostatic desalting tank during long-term operation and preventing problems such as substandard salt and water content after desalting and blackening of the desalting drainage. This patent is for a fixed mechanical agitator that cannot move with the up-and-down movement of the emulsion layer. At the same time, if the mechanical agitation speed is too low, it will not be able to disrupt the stability of the emulsion layer. If the agitation speed is too high, oil and water may mix back together, resulting in a large amount of oil and emulsion being carried away in the desalting water.

[0005] Chinese patent publication CN110903850A discloses a crude oil electrostatic desalting equipment and method, including a high-voltage pulse AC power supply system, an electrostatic desalter, a floating emulsion oil collector, an inlet pipeline, an extraction pipeline, a reinjection pipeline, a chemical dosing pipeline, a heating device, and a compact tubular electric field demulsifier. The inlet pipeline is located at the top of the electrostatic desalter, the floating emulsion oil collector is located in the emulsion layer and connected to the bottom inlet of the compact tubular electric field demulsifier, and the top outlet of the compact tubular electric field demulsifier is connected to the bottom of the electrostatic desalter. This patent solves the problems of poor operational stability and insignificant electric field effect of conventional electrostatic desalters. Furthermore, it allows for precise extraction and thorough demulsification of the emulsion layer within the electrostatic desalting tank before reinjection, ensuring that the quality of the exported crude oil meets standards and reducing the oil concentration in the desalted water. The floating emulsion oil collector of the above patent needs to be made of a material with a density similar to that of the oil-water emulsion. When processing some heavy crude oil with a density close to that of water, it may absorb the separated oil or water, making it impossible to accurately extract the emulsion layer. When the emulsion passes through the compact electric field from bottom to top, it is impossible to achieve a distribution of strong and weak electric field regions, which will reduce the electric field separation efficiency. At the same time, if the emulsion treated by the compact electric field is directly reinjected into the desalting tank, the water content of the crude oil in the tank will become higher and higher, which may lead to an increase in the desalting current, thereby affecting the stable operation of the desalting device.

[0006] Therefore, this invention proposes an emulsion layer treatment system and method in an electrostatic desalting tank to solve the problems existing in the prior art. Summary of the Invention

[0007] The purpose of this invention is to solve the problems existing in the prior art and provide a system and method for treating the emulsion layer in an electric desalting tank, which can effectively solve the problems of difficulty in removing the emulsion layer and difficulty in treating the emulsion in the electric desalting tank.

[0008] This invention is achieved through the following technical solution:

[0009] In a first aspect, the present invention provides an emulsion layer treatment system for an electrostatic desalting tank, comprising a floating oil pump and a coupled demulsification device disposed vertically within the electrostatic desalting tank;

[0010] Both ends of the floating oil pump are connected to the oil inlet of the drain pipe via hoses;

[0011] The coupling demulsifier is connected to the oil outlet of the oil drain pipe, and the coupling demulsifier is connected to the oil inlet of the electric desalting tank through the oil return line.

[0012] A further improvement of the present invention is that:

[0013] The floating oil pump includes multiple parallel oil pumping pipes, and each oil pumping pipe has multiple oil pumping holes evenly distributed on its pipe wall.

[0014] Multiple oil extraction pipes are connected to oil extraction manifolds at both ends, and two oil extraction manifolds are connected to the oil inlet of the drain pipe via flexible hoses.

[0015] A further improvement of the present invention is that:

[0016] Multiple parallel oil extraction pipes are fixed at both ends to an insulating support rod, which is connected to an explosion-proof motor via a first insulating hanger;

[0017] An interface gauge is also installed on the outer wall of the electric desalination tank, and the interface gauge is electrically connected to the explosion-proof motor.

[0018] A further improvement of the present invention is that:

[0019] The coupling demulsification device includes an emulsification tank body. Inside the emulsification tank body, an electrostatic coalescence zone, a material coalescence zone, and a corrugated plate settling zone are arranged sequentially along the running direction of the emulsion. An oil inlet pipeline is provided at one end of the emulsification tank body near the electrostatic coalescence zone. The oil inlet pipeline is connected to the oil outlet of the oil drain pipe. A demulsifier injection pipeline is also connected to the oil inlet pipeline.

[0020] A further improvement of the present invention is that:

[0021] A rectifier plate is installed inside the emulsification tank between the oil inlet pipeline and the electrostatic coalescence zone.

[0022] A further improvement of the present invention is that:

[0023] A primary oil tank is provided at the top of the emulsification tank and between the electrostatic coalescence zone and the material coalescence zone.

[0024] A secondary oil tank is installed at the top of the emulsifying tank and downstream of the corrugated plate settling zone, and a water tank is installed at the bottom of the emulsifying tank and downstream of the corrugated plate settling zone.

[0025] The primary and secondary oil tanks are connected to the oil inlet of the electric desalination tank via return oil pipelines.

[0026] A further improvement of the present invention is that:

[0027] The electrostatic coalescence region adopts a single-segment multi-layer eccentric squirrel cage-type combined electrode. The combined electrode consists of three layers of electrode components with a circular cross-section, including an outer circular electrode, a middle circular electrode, and a central electrode. Adjacent layers of electrodes form a ring-shaped electric field region. The distance between adjacent layers of electrodes gradually increases from top to bottom, forming an electric field region layout from strong to weak.

[0028] A further improvement of the present invention is that:

[0029] The combined electrode is fixed to the inner wall of the emulsifying tank by a second insulating hanger, and the combined electrode is connected to a pulse transformer fixed to the outer wall of the emulsifying tank by a high-voltage lead.

[0030] A further improvement of the present invention is that:

[0031] The corrugated plate settling zone is composed of multiple layers of sinusoidal corrugated plates, and the upper and lower ends of the sinusoidal corrugated plates have a certain gap with the inner wall of the emulsification tank.

[0032] A second aspect of the present invention provides a method for treating the emulsion layer inside an electrostatic desalting tank, wherein the above-mentioned emulsion layer treatment system for electrostatic desalting tanks is used to treat the emulsion layer inside the electrostatic desalting tank, specifically as follows:

[0033] The emulsion layer formed at the oil-water interface inside the electric desalting tank is extracted by a floating pump and sent to a coupled demulsifier. At the same time, the demulsifier is sent to the coupled demulsifier through the injection pipeline to demulsify the emulsion and achieve oil-water separation. After separation, the crude oil is reinjected into the electric desalting tank through the return pipeline, thereby realizing the resource utilization of the emulsion.

[0034] Compared with the prior art, the beneficial effects of the present invention are:

[0035] In this invention, the floating pump can be raised and lowered inside the desalting tank, and can change according to the position of the emulsion layer inside the desalting tank. This allows the floating pump to accurately extract the stubborn emulsion layer inside the desalting tank. The emulsion extracted by the floating pump enters the coupling demulsification device through a hose and an oil drain pipe. At the same time, demulsifier is added to the coupling demulsification device through a demulsifier injection line to demulsify the emulsion. The demulsified crude oil is then reinjected into the desalting tank through a return oil line, thereby realizing the resource utilization of the emulsion.

[0036] In this invention, the explosion-proof motor automatically retracts or extends the first insulating hanger based on the position information of the oil-water interface in the desalination tank detected by the interface gauge, thereby realizing the up-and-down movement of the floating oil pump. This enables precise extraction of the emulsion and discharge of the emulsion layer from the desalination tank, ensuring stable operation of the electric field area in the desalination process. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the emulsion layer treatment system inside the electrostatic desalting tank of the present invention;

[0038] Figure 2 This is a top view of the floating oil pump inside the electrostatic desalting tank of the present invention.

[0039] Figure 3 A schematic diagram showing the installation of a floating oil pumping unit inside an electrostatic desalting tank;

[0040] Figure 4This is a schematic diagram of the coupling demulsification device in this invention;

[0041] Figure 5 This is a side view of the electric field region of the coupling demulsification device in this invention.

[0042] The components include: 1. Electrostatic desalting tank; 2. Floating oil pump; 3. Coupled demulsification device; 4. Hoses; 5. Oil drain pipe; 6. Insulating support rod; 7. First insulating hanger; 8. Explosion-proof motor; 9. Interface gauge; 10. Emulsifying tank body; 11. Oil inlet pipeline; 12. Rectifier plate; 13. Electrostatic coalescence zone; 14. Pulse transformer; 15. High-voltage lead wire; 16. Second insulating hanger; 17. Primary oil tank; 18. Secondary oil tank; 19. Water tank; 20. Material coalescence zone; 21. Corrugated plate settling zone; 22. Outer circular electrode; 23. Middle circular electrode; 24. Center electrode. Detailed Implementation

[0043] The present invention will now be described in further detail with reference to the accompanying drawings:

[0044]

Example 1

[0045] like Figure 1 As shown, this embodiment of the invention provides an emulsion layer treatment system in an electric desalting tank, including a floating oil pump 2 and a coupled demulsification device 3 that are vertically and vertically disposed in an electric desalting tank 1;

[0046] The two ends of the floating oil pump 2 are connected to the oil inlet of the oil drain pipe 5 via hoses 4;

[0047] The coupling demulsifier 3 is connected to the oil outlet of the oil drain pipe 5, and the coupling demulsifier 3 is connected to the oil inlet of the electric desalting tank 1 through the return oil pipeline.

[0048] In this invention, the floating pump 2 is vertically and vertically installed inside the electrostatic desalting tank 1, and can change according to the position of the emulsion layer inside the electrostatic desalting tank 1. This allows the floating pump 2 to accurately extract the stubborn emulsion layer inside the electrostatic desalting tank 1. The emulsion extracted by the floating pump 2 enters the coupling demulsification device 3 through the hose 4 and the oil discharge pipe 5. At the same time, demulsifier is added to the coupling demulsification device 3 through the demulsifier injection pipeline to achieve demulsification of the emulsion. The crude oil after demulsification is reinjected into the electrostatic desalting tank 1 through the return oil pipeline, thereby realizing the resource utilization of the emulsion.

[0049]

Example 2

[0050] like Figure 2 As shown, the floating oil pump 2 has a tubular structure, including multiple parallel oil pumping pipes, and each oil pumping pipe has multiple oil pumping holes evenly arranged on its pipe wall.

[0051] Multiple oil extraction pipes are connected to oil extraction manifolds at both ends. The two oil extraction manifolds are connected to the oil inlet of the oil drain pipe 5 through hoses 4. The emulsion enters the oil extraction pipe through the oil extraction hole, and then is sent to the coupling demulsification device 3 through the oil drain manifolds, hoses and oil drain pipes at both ends in sequence to achieve demulsification and oil-water separation.

[0052] Preferably, the two ends of the hose 4 are flexibly connected to the main oil extraction pipe and the drain pipe, respectively, so that the floating oil extractor 2 can work normally when it moves up and down.

[0053] Preferably, the hose 4 is a hose made of silicone or polytetrafluoroethylene.

[0054]

Example 3

[0055] like Figure 2 and Figure 3 As shown, the two ends of multiple parallel oil extraction pipes are fixed to the insulating support rod 6. The insulating support rod 6 is connected to the explosion-proof motor 8 through the first insulating hanger 7. Specifically, the explosion-proof motor 8 is fixed to the outer wall of the electric desalination tank 1. The output shaft of the explosion-proof motor 8 is connected to one end of the first insulating hanger 7, and the other end of the first insulating hanger 7 is connected to the insulating support rod 6. The explosion-proof motor 8 controls the raising and lowering of the first insulating hanger 7, thereby controlling the raising and lowering of the floating oil extractor 2, so as to ensure that during the oil extraction process, the floating oil extractor extracts as much of the emulsion layer at the oil-water interface as possible, and extracts as little of the separated oil or water phase as possible.

[0056] An interface gauge 9 is also installed on the outer wall of the electric desalting tank 1 to monitor the position information of the oil-water interface in the electric desalting tank 1 in real time. The interface gauge 9 is electrically connected to the explosion-proof motor 8. The explosion-proof motor 8 receives the position information of the oil-water interface sent by the interface gauge 9 and automatically retracts or extends the first insulating hanger 7 according to the position information to realize the up and down movement of the floating oil pump 2. This ensures that during the oil pumping process, the floating oil pump 2 extracts as much of the emulsion layer of the oil-water interface as possible and extracts as little of the separated oil or water phase as possible.

[0057] Preferably, both the first insulating hanger 7 and the insulating support rod 6 are made of polytetrafluoroethylene (PTFE).

[0058]

Example 4

[0059] like Figure 4 and Figure 5As shown, the coupled demulsification device 3 is a horizontal structure, including an emulsification tank body 10. Inside the emulsification tank body 10, an electrostatic coalescence zone 13, a material coalescence zone 20, and a corrugated plate settling zone 21 are arranged sequentially along the running direction of the emulsion. An oil inlet pipeline 11 is provided at one end of the emulsification tank body 10 near the electrostatic coalescence zone 13. The oil inlet pipeline 11 is connected to the oil outlet of the oil outlet pipe 5. A demulsifier injection pipeline is also connected to the oil inlet pipeline 11. The emulsion extracted from the floating pump 2 enters the coupled demulsification device 3 sequentially through the hose 4, the oil outlet pipe 5, and the oil inlet pipeline 11. At the same time, the demulsifier is sent to the coupled demulsification device 3 through the demulsifier injection pipeline. The emulsion undergoes oil-water separation through electrostatic coalescence, material coalescence, and corrugated plate settling in sequence. The separated crude oil is reinjected into the electrostatic desalting tank 1 through the return oil pipeline, thereby realizing the resource utilization of the emulsion.

[0060] Preferably, a rectifier plate 12 is provided inside the emulsion tank body 10 between the oil inlet line 11 and the electrostatic coalescence zone 13. The emulsion enters the electrostatic coalescence zone 13 after its flow state is stabilized by the rectifier plate 12.

[0061] Preferably, a primary oil pack 17 is provided at the top of the emulsion tank 10 and between the electrostatic coalescence zone 13 and the material coalescence zone 20. After the emulsion undergoes deep separation in the electrostatic coalescence zone 13, the upper separated oil phase is recovered by the primary oil pack 17, while the remaining oil droplets with larger particle sizes that have not been separated from the aqueous phase enter the material coalescence zone 20.

[0062] Preferably, a secondary oil reservoir 18 is provided at the top of the emulsifying tank 10 and downstream of the corrugated plate settling zone 21, and a water reservoir 19 is provided at the bottom of the emulsifying tank 10 and downstream of the corrugated plate settling zone 21. The crude oil after oil-water separation in the material aggregation zone 20 and the corrugated plate settling zone 21 is recovered by the secondary oil reservoir 18, while the water phase that settles down is discharged from the water reservoir 19 at the bottom of the emulsifying tank 10, thereby realizing oil-water separation of the emulsion.

[0063] The primary oil tank 17 and the secondary oil tank 18 are connected to the inlet of the electric desalting tank 1 through the return oil pipeline. The crude oil recovered in the primary oil tank 17 and the secondary oil tank 18 is reinjected into the electric desalting tank 1 through the return oil pipeline, realizing the resource utilization of the emulsion.

[0064]

Example 5

[0065] like Figure 5As shown, the electrostatic coalescence zone 13 adopts a single-segment multi-layer eccentric squirrel cage combined electrode. The combined electrode consists of three layers of electrode components with a circular cross-section, including an outer circular electrode 22, a middle circular electrode 23, and a central electrode 24. Adjacent electrode layers form a ring electric field region, and the spacing between adjacent electrode layers gradually increases from top to bottom, forming an electric field region layout from strong to weak. At the same time, the electrodes are covered with insulating material, which can effectively solve the problems of reduced electric field strength or short circuit caused by excessive current when processing high water content emulsions, ensuring equipment safety and operational stability.

[0066] The combined electrode is fixed to the inner wall of the emulsifying tank 10 by the second insulating hanger 16. The combined electrode is connected to the pulse transformer 14 fixed to the outer wall of the emulsifying tank 10 by the high voltage lead 15. The pulse transformer 14 can change the input power of the transformer according to the load change, thereby achieving the best desalination effect.

[0067]

Example 6

[0068] Within the material aggregation zone 20, oleophilic-hydrophobic or hydrophilic-oleophobic fiber materials are used as fillers with a density of 750–850 g / L. The oleophilic-hydrophobic materials can be polypropylene fibers, polytetrafluoroethylene fibers, or natural cellulose fibers; the hydrophilic-oleophobic materials can be silver fibers or nylon fibers. Small oil droplets entrained in the emulsion can quickly form an oil film on the oleophilic-hydrophobic surface, and after detachment, form large oil droplets, realizing the transformation from dispersed to free oil droplets.

[0069] The residence time of the emulsion in the material coalescence zone 20 is 10–45 min.

[0070]

Example 7

[0071] The corrugated plate settling zone 21 is composed of multiple sinusoidal corrugated plates. The upper and lower ends of the sinusoidal corrugated plates have a certain gap with the inner wall of the emulsion tank body 10. The emulsion, after being treated by the electrostatic coalescence zone 13 and the material coalescence zone 20, enters the corrugated plate settling zone 21. The multiple sinusoidal corrugated plates increase the probability of oil droplet collision. The oil droplets gather at the top of the wave crest and float upward. At the same time, it accelerates the sedimentation of the aqueous phase to further achieve oil-water separation. The separated crude oil is recovered by the secondary oil bag 18 and reinjected into the electrostatic desalting tank 1. Meanwhile, the sedimented aqueous phase is discharged from the water bag 19 at the bottom of the emulsion tank body 10, realizing the oil-water separation and resource utilization of the emulsion.

[0072] Preferably, the sinusoidal corrugated plate is made of materials such as polypropylene, polytetrafluoroethylene, and stainless steel.

[0073]

Example 8

[0074] This invention provides a method for treating the emulsion layer inside an electrostatic desalination tank. The method utilizes the emulsion layer treatment system described in the above embodiments to treat the emulsion layer inside the electrostatic desalination tank. Specifically:

[0075] The crude oil is fed into the electrostatic desalting tank 1 from the bottom via a distributor and distributed to the vicinity of the electric field area. After separation by the electric field, the desalted crude oil leaves the electrostatic desalting unit from the top of the electrostatic desalting tank 1, while the electrostatic desalting water leaves the unit from the bottom of the electrostatic desalting tank 1. The emulsion layer formed at the oil-water interface is extracted by the floating oil pump 2 and pumped to the coupled demulsification unit 3. At the same time, the demulsifier is also sent to the coupled demulsification unit 3 through the injection pipeline. The oil and water are separated in sequence through electrostatic coalescence, material coalescence and corrugated plate settling zone. After separation, the crude oil is reinjected into the electrostatic desalting tank 1 through the return oil pipeline, thereby realizing the resource utilization of the emulsion. Meanwhile, the discharged high-salt wastewater is sent to the next treatment unit along with the electrostatic desalting water.

[0076] In this invention, since the floating oil extractor 2 can be raised and lowered inside the electric desalting tank 1, it can change according to the position of the emulsion layer inside the electric desalting tank 1, so that the floating oil extractor 2 can accurately extract the stubborn emulsion layer inside the electric desalting tank 1.

[0077] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0078] In the description of this invention, unless otherwise stated, the terms "upper," "lower," "left," "right," "inner," "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0079] The above technical solution is only one embodiment of the present invention. For those skilled in the art, based on the principles disclosed in the present invention, it is easy to make various types of improvements or modifications, and not limited to the technical solutions described in the specific embodiments of the present invention. Therefore, the foregoing description is only a preferred option and is not restrictive.

Claims

1. A system for treating an emulsion layer inside an electrostatic desalting tank, characterized in that, This includes a floating oil pump and a coupled demulsifier that are vertically mounted inside the electric desalting tank; Both ends of the floating oil pump are connected to the oil inlet of the drain pipe via hoses; The coupling demulsifier is connected to the oil outlet of the oil drain pipe, and the coupling demulsifier is connected to the oil inlet of the electric desalting tank through the oil return line.

2. The system according to claim 1, characterized in that, The floating oil pump includes multiple parallel oil pumping pipes, and each oil pumping pipe has multiple oil pumping holes evenly distributed on its pipe wall. Multiple oil extraction pipes are connected to oil extraction manifolds at both ends, and two oil extraction manifolds are connected to the oil inlet of the drain pipe via flexible hoses.

3. The system according to claim 2, characterized in that, Multiple parallel oil extraction pipes are fixed at both ends to an insulating support rod, which is connected to an explosion-proof motor via a first insulating hanger; An interface gauge is also installed on the outer wall of the electric desalination tank, and the interface gauge is electrically connected to the explosion-proof motor.

4. The system according to claim 1, characterized in that, The coupling demulsification device includes an emulsification tank body. Inside the emulsification tank body, an electrostatic coalescence zone, a material coalescence zone, and a corrugated plate settling zone are arranged sequentially along the running direction of the emulsion. An oil inlet pipeline is provided at one end of the emulsification tank body near the electrostatic coalescence zone. The oil inlet pipeline is connected to the oil outlet of the oil drain pipe. A demulsifier injection pipeline is also connected to the oil inlet pipeline.

5. The system according to claim 4, characterized in that, A rectifier plate is installed inside the emulsification tank between the oil inlet pipeline and the electrostatic coalescence zone.

6. The system according to claim 4, characterized in that, A primary oil tank is provided at the top of the emulsification tank and between the electrostatic coalescence zone and the material coalescence zone. A secondary oil tank is installed at the top of the emulsifying tank and downstream of the corrugated plate settling zone, and a water tank is installed at the bottom of the emulsifying tank and downstream of the corrugated plate settling zone. The primary and secondary oil tanks are connected to the oil inlet of the electric desalination tank via return oil pipelines.

7. The system according to claim 4, characterized in that, The electrostatic coalescence region adopts a single-segment multi-layer eccentric squirrel cage-type combined electrode. The combined electrode consists of three layers of electrode components with a circular cross-section, including an outer circular electrode, a middle circular electrode, and a central electrode. Adjacent layers of electrodes form a ring-shaped electric field region. The distance between adjacent layers of electrodes gradually increases from top to bottom, forming an electric field region layout from strong to weak.

8. The system according to claim 7, characterized in that, The combined electrode is fixed to the inner wall of the emulsification tank by a second insulating hanger, and the combined electrode is connected to a pulse transformer fixed to the outer wall of the emulsification tank by a high-voltage lead.

9. The system according to claim 4, characterized in that, The corrugated plate settling zone is composed of multiple layers of sinusoidal corrugated plates, and the upper and lower ends of the sinusoidal corrugated plates have gaps with the inner wall of the emulsification tank.

10. A method for treating the emulsion layer inside an electrostatic desalting tank, characterized in that, The treatment of the emulsion layer inside the electrostatic desalting tank is achieved by using the emulsion layer treatment system described in any one of claims 1-9, specifically as follows: The emulsion layer formed at the oil-water interface inside the electric desalting tank is extracted by a floating pump and sent to a coupled demulsifier. At the same time, the demulsifier is sent to the coupled demulsifier through the injection pipeline to demulsify the emulsion and achieve oil-water separation. After separation, the crude oil is reinjected into the electric desalting tank through the return pipeline, thereby realizing the resource utilization of the emulsion.

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