High-efficiency coalescing separator combination device and method for oil-water separation by using high-efficiency coalescing separator combination device

Abstract

The invention discloses a high-efficiency coalescence separator combination device which comprises a horizontal tank body, one end of the tank body is provided with a liquid inlet, and the bottom of the other end of the tank body is provided with a water outlet; a first-stage rapid separation module, a combined fiber coalescence module and a second-stage coalescence separation module are sequentially arranged in the tank body in the fluid flowing direction; wherein the top of the tank body is provided with an oil bag used for collecting a separated oil phase, and the bottom of the tank body is provided with a desanding pipeline used for removing deposited solids. The invention also discloses an oil-water separation method of the device. Oil-water two-phase separation is achieved through the self-adaptive rotational flow core pipe, the combined fiber coalescence structure and the rapid separation module coupling structure, and efficient and rapid separation is carried out on treatment objects with complex incoming liquid working conditions (heavy thick oil, severe incoming liquid fluctuation, high suspended matter impurity concentration and the like). The device has an excellent effect on a treatment object of a heavy oil field, and the technological process is remarkably shortened while the high separation efficiency is guaranteed.

Description

Technical Field

[0001] This invention belongs to the fields of petrochemical and environmental protection technology, specifically relating to a novel, highly efficient coalescing separator assembly and its method for oil-water separation. Background Technology

[0002] Oily wastewater is one of the most common and difficult-to-treat pollutants in industrial production processes, widely present in fields such as oil extraction, oil refining, iron and steel metallurgy, machining, food processing, and marine transportation. Direct discharge of untreated oily wastewater can cause lasting and serious harm to water bodies, soil, and ecosystems. Furthermore, the oil in wastewater is a valuable resource, and its effective recovery has significant economic value.

[0003] The presence of emulsified oil in oily wastewater poses a significant challenge to oil-water separation. An emulsion can be understood as a relatively stable dispersion system composed of oil, water, and surfactants. Surfactants are molecules possessing both hydrophilic and lipophilic groups, which adsorb onto the droplet interface. The hydrophilic portion forms a barrier preventing oil droplet aggregation, while the lipophilic portion forms a barrier preventing water droplet aggregation, thus maintaining the emulsion's stability. However, naturally occurring or synthetic surfactant molecules commonly found in wastewater adsorb onto the surface of oil droplets, forming a film that prevents contact and aggregation between tiny oil droplets, resulting in a difficult-to-separate oil-in-water emulsion. For this type of emulsion, traditional gravity separation methods are completely ineffective due to the near-zero settling (or floating) velocity of the oil droplets. While air flotation can remove some, its effectiveness is limited for emulsified oil with high interfacial film strength, and the addition of reagents increases the complexity and cost of subsequent treatment. Although membrane separation offers high separation precision, it suffers from rapid membrane flux decay, frequent cleaning, and high operating costs when treating emulsified oils, especially high-concentration or heavy oily wastewater. Therefore, demulsification and coalescence technologies for emulsions are particularly important.

[0004] Coalescing separation technology utilizes the selective wetting effect and microporous structure of coalescing materials to force emulsified oil droplets to collide, rupture the interfacial film, and coalesce and grow as they pass through the material, achieving a demulsification effect. Traditional coalescing materials, including quartz sand, glass fiber, and stainless steel fiber, are prone to surface adhesion and clogging when processing high-viscosity heavy oils, significantly reducing coalescing performance and treatment efficiency, and making regeneration and recovery difficult. Furthermore, some materials lack sufficient mechanical strength, making them susceptible to fiber breakage, structural collapse, or compression under high flow rate or high pressure fluctuations, leading to decreased separation efficiency and shortened service life.

[0005] Therefore, there is an urgent need for a method and apparatus for oil-water separation that can handle heavy oil, provide stability, and operate at low cost. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems of low efficiency in treating emulsified oil, easy clogging and damage of coalescing materials, and poor adaptability to working conditions in traditional oil-water separation technology. It provides a modular and flexibly combinable oil-water separation device and method, which achieves efficient, stable and low-cost separation through a step-coupling process.

[0007] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows:

[0008] A first aspect of the present invention provides a high-efficiency coalescing separator assembly, comprising:

[0009] A horizontal tank, wherein one end of the tank is provided with a liquid inlet and the bottom of the other end is provided with a water outlet;

[0010] Inside the tank, along the direction of fluid flow, are arranged in sequence as follows:

[0011] The first-stage rapid separation module is used to receive the incoming liquid and perform flow field rectification and initial coalescence of oil droplets. It includes a combination of parallel flow stabilizers, stepped flow guides, corrugated coalescing plates, corrugated flow guides, or non-uniform parallel plate assemblies.

[0012] A composite fiber coalescing module, connected downstream of the primary rapid separation module, is used for deep demulsification of the liquid phase containing emulsified oil. The module is composed of oleophilic and hydrophobic fibers and hydrophilic and oleophobic fibers in proportion, and is equipped with an integrated air purging pipeline.

[0013] A secondary coalescing separation module is connected downstream of the combined fiber coalescing module and is used for the final separation of oil and water;

[0014] The tank has an oil bag at the top for collecting the separated oil phase and a sand removal pipeline at the bottom for removing deposited solids.

[0015] According to a preferred embodiment of the present invention, an adaptive cyclone core tube is further disposed upstream of the primary rapid separation module; the adaptive cyclone core tube is composed of a main separation tube, a secondary separation tube and a connecting tube, and is arranged vertically or horizontally within the tank.

[0016] Furthermore, the single-tube processing capacity of the adaptive cyclone core is 5 m³ / h or 10 m³ / h, and the operating pressure drop is no greater than 0.2 MPa.

[0017] Preferably, in the composite fiber coalescing module, the ratio of oleophilic and hydrophobic fibers to hydrophilic and oleophilic fibers is 3:7 to 7:3; for light oils, the proportion of oleophilic fibers is 60% to 70%; for heavy oils, the proportion of hydrophilic fibers is 60% to 70%.

[0018] Furthermore, the combined fiber coalescing module is a parallel plate structure, with the air purging pipeline laid in the flow channel between the plates; or, it is a full-section structure that fills the entire flow cross-section of the tank, with the air purging pipeline laid on its surface.

[0019] According to a preferred embodiment of the present invention, the oil pack includes a first oil pack and a second oil pack, the first oil pack being located on top of the tank behind the primary rapid separation module, and the second oil pack being located on top of the tank behind the secondary coalescing separation module; the first oil pack can be replaced by a gas pack with a gas deliquescence module inside.

[0020] Preferably, the sand removal pipeline consists of two parallel pipelines laid parallel to the central axis of the bottom of the tank, and the pipelines are equipped with sand removal nozzles with spray directions at 45° and 90° angles to the pipeline axis.

[0021] Furthermore, the stepped guide plates are arranged in the flow direction such that the width of the plates decreases step by step, or the height of the plates decreases step by step; or in the vertical direction, the density between the plates decreases from bottom to top.

[0022] A second aspect of the present invention provides a method for oil-water separation using the apparatus described above, comprising the following steps:

[0023] S1. The oil-water mixture is passed through a primary rapid separation module to eliminate fluid turbulence and promote the collision and initial coalescence of oil droplets, resulting in a preliminarily separated oil phase and an aqueous phase containing emulsified oil.

[0024] S2. The aqueous phase containing emulsified oil obtained in step S1 is passed through a combined fiber coalescence module, and the fiber bed is used to make the micro emulsified oil droplets coalesce and grow, resulting in a deeply demulsified liquid phase.

[0025] S3. The liquid phase obtained after deep demulsification in step S2 is further coalesced and separated by a two-stage coalescing separation module to finally obtain a collectable oil phase and a water phase that meets the discharge or reuse standards.

[0026] Before step S1, depending on whether the oil phase density of the incoming liquid is less than 900 kg / m³ and the oil content is less than 1000 ppm, the oil-water mixture is selectively pretreated by cyclone centrifugation through an adaptive cyclone core tube.

[0027] According to a preferred embodiment of the present invention, in step S2, the combined fiber coalescing module is periodically purged and regenerated by the air purging pipeline; and / or, depending on whether the processing capacity of the device is less than 150 m³ / h, a combined fiber coalescing module with a parallel plate type or a full cross-section structure is selected.

[0028] The beneficial effects of this invention are as follows:

[0029] 1. This invention achieves oil-water two-phase separation through an adaptive cyclone core tube, a combined fiber coalescing structure, and a rapid separation module coupling structure, enabling efficient and rapid separation of processing objects with complex incoming liquid conditions (heavy oil, drastic fluctuations in incoming liquid, and high concentrations of suspended impurities).

[0030] 2. The present invention has an oil phase removal efficiency of over 97% in water, and the pressure drop and water phase residence time are only 50% and 30% of those of the "inclined plate oil separator + aerated flotation" method, respectively. It also has extremely high operational flexibility in terms of the target and throughput (maximum operational flexibility 0-160%), and is highly effective for heavy oilfields. While ensuring high separation efficiency, it significantly shortens the process flow, effectively reduces the footprint of the treatment system, and eliminates or reduces the use of a large number of chemical reagents, thus making up for the shortcomings of the prior art. Attached Figure Description

[0031] Figure 1 A schematic diagram of the first combination method and device for a high-efficiency coalescing separator;

[0032] Figure 2 A schematic diagram of the first combination method and apparatus for a high-efficiency coalescing separator (the first oil tank is an air tank);

[0033] Figure 3 A top view of the structure of the first combination method and device for a high-efficiency coalescing separator;

[0034] Figure 4 This is a schematic diagram of the longitudinal arrangement of adaptive cyclone core tubes, where... Figure 4 A is a left view showing the longitudinal arrangement of adaptive swirl core tubes. Figure 4 B is a top view of the longitudinal arrangement of adaptive swirl core tubes;

[0035] Figure 5 This is a cross-sectional structural diagram of the coalescing plate assembly, in which... Figure 5 A is a parallel flow stabilizer. Figure 5 B is a stepped guide vane. Figure 5 C represents a corrugated coalescing plate. Figure 5 D is a corrugated guide vane. Figure 5 E represents a non-uniform parallel plate assembly.

[0036] Figure 6 The diagram shows three structural designs for the stepped guide vane combination. Figure 6 A is a schematic diagram of the first type of stepped guide vane combination (with vane width decreasing step by step). Figure 6 B is a schematic diagram of the second type of stepped guide vane combination (with the vane height decreasing step by step). Figure 6 C is a schematic diagram of the third type of stepped guide vane combination (with increasing density between the vanes);

[0037] Figure 7 This is a structural schematic diagram of a parallel-plate composite fiber coalescing module, in which... Figure 7 A is a top view of a parallel plate-type composite fiber coalescing module. Figure 7 B is the left view of the parallel plate-type composite fiber coalescing module;

[0038] Figure 8 A schematic diagram of fiber weaving structures with different shapes is provided. Figure 8 A is a schematic diagram of an Ω-shaped composite fiber braiding structure. Figure 8 B is a schematic diagram of an X-type composite fiber weaving structure.

[0039] Figure 9 This is a schematic diagram of the nitrogen purging pipes arranged on a parallel plate-type composite fiber coalescing module, wherein... Figure 9 A is a top view of the nitrogen purging pipes arranged on the parallel plate-type composite fiber coalescing module. Figure 9 B is a left view of the nitrogen purging pipes arranged on the parallel plate composite fiber coalescing module;

[0040] Figure 10 A schematic diagram of the annular spiral distribution structure of a nitrogen purging pipe;

[0041] Figure 11 A schematic diagram of the second combination method of the high-efficiency coalescing separator (longitudinal distribution of core tubes, small processing capacity) and the structure of the device;

[0042] Figure 12 This is a schematic diagram of the structure of a full-section fiber coalescing module, in which... Figure 12 A is a top view of the full-section fiber coalescing module. Figure 12 B is the left view of the full-section fiber coalescing module;

[0043] Figure 13 This is a schematic diagram of the nitrogen purging pipes arranged on a full-section composite fiber coalescing module, wherein... Figure 13 A is a top view of the nitrogen purging pipes arranged on the full-section composite fiber coalescing module. Figure 13 B is a left view of the nitrogen purging pipes arranged on the full-section composite fiber coalescing module;

[0044] Figure 14 This is a schematic diagram of the third combination method (lateral distribution of core tubes) for a high-efficiency coalescing separator and the structure of the device.

[0045] Figure 15 This is a schematic diagram of a structure with adaptive cyclone core tubes arranged laterally, where... Figure 15 A is a top view of the laterally arranged adaptive swirl core tubes. Figure 15 B is a left view of the adaptive swirl core tubes arranged laterally;

[0046] Figure 16 This is a schematic diagram of the fourth combination method of a high-efficiency coalescing separator (with transverse core tube distribution and small processing capacity) and the structure of the device.

[0047] Figure 17 This is a schematic diagram of the fifth combination method (coreless tube) of a high-efficiency coalescing separator and the structure of the device;

[0048] Figure 18 This is a schematic diagram of the sixth combination method (coreless, small throughput) of a high-efficiency coalescing separator and the structure of the device.

[0049] Figure 19 This is a schematic diagram of the seventh combination method (low inlet oil content) of a high-efficiency coalescing separator and the structure of the device;

[0050] Figure 20 This is a schematic diagram of the eighth combination mode of the high-efficiency coalescing separator (low inlet oil content, small processing capacity) and the structure of the device;

[0051] Figure 21 This is a schematic diagram of the ninth combination mode of a high-efficiency coalescing separator (low inlet oil content, small processing capacity, and oil collection at the tail end of the tank) and the structure of the device.

[0052] Among them, 1-liquid inlet; 2-adaptive cyclone core tube; 3-first-stage rapid separation module; 4-oil tank; 5-parallel plate combined fiber coalescing module; 6-air purging pipeline; 7-secondary coalescing separation module; 8-water outlet; 9-sand removal pipeline; 10-full cross-section combined fiber coalescing module; 12-weir plate; 13-oil collection chamber; 14-oil outlet; 11-liquid inlet distribution pipe; 21-main separation pipe; 22-secondary separation pipe; 23-main and secondary pipe connecting pipe; 24-connector; 41-first oil tank; 42-second oil tank; 43-air tank; 44-gas dehydration module; 45-air outlet; 61-air purging air inlet; 62-air purging main pipe; 63-air purging branch pipe; 64-air purging nozzle; 65-connecting pipe; sand removal nozzle-91. Detailed Implementation

[0053] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only 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.

[0054] This invention provides a high-efficiency coalescing separator device and its combination method. Its core lies in achieving efficient separation of emulsified oil through step-coupling process and optimized structural design, meeting the processing needs under complex working conditions.

[0055] Example 1: High-efficiency coalescing separator device and separation method of the first combination

[0056] 1.1 The first type of combination device composition

[0057] like Figure 1 As shown, the main body of the high-efficiency coalescing separator assembly in this embodiment is a horizontal tank. One end of the tank has an inlet 1 for introducing the oil-water two-phase mixture to be treated, and the bottom of the other end of the tank has an outlet 8 for discharging the separated aqueous phase. Inside the tank, arranged sequentially according to the fluid flow direction, are an adaptive cyclone core tube 2, a primary rapid separation module 3, a combined fiber coalescing module 5, a gas purging line 6, and a secondary coalescing separation module 7. The top of the tank has an oil tank 4 for collecting the oil and gas phases. The oil tank 4 includes a first oil tank 41 and a second oil tank 42. The first oil tank 41 is installed on the top of the tank behind the primary rapid separation module 3, and the second oil tank 42 is installed on the top of the tank behind the secondary coalescing separation module 7. The bottom of the tank has a sand removal line 9 for removing deposited solid impurities.

[0058] like Figure 2 As shown, the device consists of the first combination, and the first oil bag can also be replaced with an air bag 43, which is equipped with a gas dehydration module 44.

[0059] Figure 3 This is a top view of the first type of combined device, such as... Figure 3 As shown, one end of the tank is provided with an air purge inlet 61, which is connected to the air purge main pipe 62. A connecting pipe 65 passes through the middle of the air purge main pipe 62. Several air purge branch pipes 63 are also arranged horizontally inside the air purge main pipe 62 that passes through the combined fiber coalescing module 5. An air purge nozzle 64 is vertically installed at one end of each air purge branch pipe 63, and the air purge nozzle 64 faces the combined fiber coalescing module 5.

[0060] The liquid inlet 1 is connected to the liquid distribution pipe 11 via a flange. Figure 1 and Figure 3 As shown, the liquid distribution pipe 11 is evenly distributed on both sides of the liquid inlet 1. Its function is to evenly distribute the oil-water mixture to be treated to the subsequent processing unit to ensure the stability of the flow.

[0061] The uniformly distributed fluid then enters the adaptive vortex core tube 2 for initial centrifugal separation. For example... Figure 4 A and Figure 4As shown in Figure B, the adaptive cyclone core tube 2 adopts the structure described in CN112387013A, consisting of a main separation tube 21, a secondary separation tube 22, a connecting main and secondary tube 23, and a connector 24. The adaptive cyclone core tubes 2 are arranged vertically and fixed inside the tank via threaded connections using the connectors 24. All adaptive cyclone core tubes 2 are parallel to each other. The core tube material can be selected from 316L stainless steel, carbon steel, polypropylene (PP), polytetrafluoroethylene (PTFE), or high-strength aerospace resin. Specifications include single-tube processing capacities of 5 m³ / h and 10 m³ / h. During operation, the pressure drop is ≤0.2 MPa, achieving high-efficiency separation while reducing energy consumption.

[0062] like Figure 5 As shown, the primary rapid separation module 3 can be freely combined with plate groups according to the operating conditions, including but not limited to parallel flow stabilizer 31, stepped guide plate 32, corrugated coalescing plate 33, corrugated guide plate 34, and non-uniform parallel plate assembly 35. The arrangement of different stepped guide plates 32 is stepped, with the width of the plates decreasing sequentially along the liquid flow direction (e.g., ...). Figure 6 (as shown in A) or height (as shown in A) Figure 6 (As shown in B); or, within the same stepped guide vane 32, along the vertical height direction, from bottom to top (i.e., the direction of oil phase rising), the density between the vanes gradually decreases (e.g., as shown in B). Figure 6 (As shown in C). The liquid passes through the first-stage rapid separation module 3 to eliminate turbulence interference and cause oil droplets to collide and coalesce. After the small oil droplets coalesce and grow, they float to the surface and flow into the first oil pack 41. The aqueous phase (containing emulsified oil) enters the combined fiber coalescing module 5.

[0063] like Figure 7 , Figure 8 As shown, the composite fiber coalescing module 5 is composed of oleophilic-hydrophobic fibers and hydrophilic-oleophobic fibers in a ratio of 3:7 to 7:3. For light oils, 60% to 70% of the fibers are oleophilic, and for heavy oils, 60% to 70% are hydrophilic. The coalescing bed is constructed using an X / Ω weave, and the materials include nylon, glass fiber, metallic wool, or polyester fiber. Figure 9 As shown, the composite fiber coalescing module 5 adopts a parallel plate structure with flow channels between the plates; the air purging pipeline 6 is laid between the two plates of the parallel plate composite fiber coalescing module 5, and is composed of an air purging main pipe 62 and air purging branch pipes 63. The air purging branch pipes 63 are equidistantly distributed on the air purging main pipe 62, and an air purging nozzle 64 is installed at one end of the air purging branch pipe 63, with the air purging nozzle 64 facing the composite fiber coalescing module 5; or, as Figure 10 The air purging pipeline 6 shown is distributed in a ring-shaped spiral. Multiple air purging nozzles 64 are evenly distributed along the circumference of the ring-shaped pipeline. The spraying range covers the entire combined fiber coalescing module 5. Air is sprayed out from the air purging nozzles 64 to clean the impurities intercepted in the fiber, so that the fiber can be regenerated. The purging gas is nitrogen or production gas.

[0064] The secondary coalescence separation module 7 is similar in structure to the primary rapid separation module 3, but focuses on coalescence separation. The baffle width is extended to increase the probability of oil droplet collision, which causes the small oil droplets after demulsification to coalesce and grow into large oil droplets that flow into the second oil pack 42, while the aqueous phase sinks and is finally discharged from the outlet 8.

[0065] The sand removal pipeline 9 at the bottom of the tank adopts the structure described in CN202508938U, consisting of two parallel DN50 pipelines laid parallel to each other on the central axis of the bottom of the tank. The material is not less than 316L. Each pipeline has nozzles 91 arranged at equal intervals along the axial direction, and each cross section is equipped with two sand removal nozzles 91. The spraying direction is at an angle of 45° and 90° to the pipeline axis, and the coverage area is 0.25~0.3m².

[0066] 1.2 Separation Method of the First Combination

[0067] The separation method in this embodiment is adapted to the first type of combined device, and the specific steps are as follows:

[0068] S1. Preliminary separation of heavy oil: The incoming liquid enters from the inlet 1 and is evenly distributed through the inlet distribution pipe 11. The incoming liquid enters the adaptive cyclone core tube 2 for cyclone separation—the oil phase, as the light phase, flows into the oil tank 4 through the secondary separation pipe 22, while the water phase, as the heavy phase, flows into the primary rapid separation module 3 from the main separation pipe 21.

[0069] S2. Rectification and Initial Coagulation: The liquid phase passes through the first-stage rapid separation module 3, where it undergoes rectification, distribution, and initial coalescence. The oil reservoir setting is determined based on the pressure difference between the upstream equipment and the CFC equipment, and the gas-liquid ratio: If the pressure difference > 200 kPa or the gas-liquid ratio ≥ 0.1, the first oil reservoir 41 is set as a gas reservoir, and the gas phase is discharged from the gas reservoir; if the pressure difference ≤ 200 kPa and the gas-liquid ratio < 0.1, both stages are set as oil reservoirs, and a small amount of gas is discharged with the oil phase. The plate assembly eliminates turbulence, promoting the coalescence and upward floating of small oil droplets.

[0070] S3. Deep Demulsification and Separation: The liquid phase enters the combined fiber coalescing module 5. Under the action of inertial collision, diffusion interception, and induced interception, the fiber bed causes smaller oil droplets to coalesce into larger oil droplets. The gas purging pipeline 6 is periodically purged to remove fiber impurities and maintain module regeneration; the purging frequency is adjusted according to the impurity load.

[0071] S4. Rapid coalescence and flotation: The liquid phase passes through the secondary coalescence separation module 7 for enhanced separation; the uncoalesced tiny oil droplets coalesce between the plates, the oil phase floats up and flows into the oil tank 4, and the water phase sinks and is discharged from the outlet pipe 8.

[0072] Example 2: A second combination of a high-efficiency coalescing separator device and separation method

[0073] 2.1. Composition of the second type of combination device

[0074] like Figure 11 As shown, the main structure of the second combination is basically the same as that of the first combination. The core difference is that the combined fiber coalescing module 5 is replaced by a full-section combined fiber coalescing module 10, which is suitable for working conditions with a processing capacity of <150m³ / h, in order to save space.

[0075] The full-section module 10 has a columnar structure, combined with... Figure 12 As shown, the full-section composite fiber coalescing module 10 is constructed from a coalescing bed made of oleophilic and hydrophobic fibers in a specific ratio, with materials including nylon, glass fiber, metallic wool, or polyester fiber. Combined with... Figure 13 As shown, the air purging line 6 is laid on the surface of the full-section composite fiber coalescing module 10, with the line arrangement covering the entire module cross-section and the nozzles evenly distributed. The remaining components are the same as in Example 1.

[0076] 2.2 Separation method for the second combination

[0077] The separation method, based on the overall steps, is adapted to a second type of combined device:

[0078] S1. Preliminary separation of heavy oil: Same as in Example 1.

[0079] S2, Rectification and Preliminary Coagulation: The liquid phase is processed by the first-stage rapid separation module 3, and the baffle combination is freely selected according to the properties of the incoming liquid.

[0080] S3, Deep Demulsification Separation: The liquid phase enters the full-section composite fiber coalescing module 10 for deep demulsification; this module is used when the unit's throughput is <150m³ / h, and a parallel plate structure is used if the throughput is ≥150m³ / h. The air purging pipeline 6 operates periodically, with the nozzles covering the entire cross-section.

[0081] S4. Rapid aggregation and floating: The final separation steps are the same as in Example 1. The full-section structure optimizes space, making it suitable for small processing stations.

[0082] Example 3: A third combination of a high-efficiency coalescing separator device and separation method

[0083] 3.1 The third type of combination of devices

[0084] like Figure 14 As shown, the core difference in the third combination lies in the adaptive swirl core tube 2, which is arranged horizontally and laterally in the upper part of the inlet chamber to adapt to space-constrained scenarios. Combined with... Figure 15 As shown, when the adaptive vortex core tube 2 is arranged horizontally, the liquid inlet 1 is located in an independent chamber below the core tube, and the liquid distribution pipe 11 ensures uniform distribution of the incoming liquid.

[0085] The primary rapid separation module 3 can be arranged in the upper part of the inlet chamber, with a height of 3 / 5 of the tank diameter. The remaining components are the same as in Embodiment 1.

[0086] 3.2 Separation method for the third combination

[0087] Separation method adapted for horizontally arranged core tubes:

[0088] S1. Preliminary separation of heavy oil: After the incoming liquid is evenly distributed through the inlet distribution pipe 11, it enters the horizontally arranged adaptive cyclone core tube 2 from the bottom; the cyclone separation steps are the same as in Example 1, but the centrifugal effect is more suitable for high flow conditions when arranged horizontally.

[0089] S2, Rectification and Preliminary Coagulation: The liquid phase is processed by the first-stage rapid separation module 3. The module height is adapted to the tank space, and the baffle combination is adjusted according to the fluctuation of the incoming liquid.

[0090] S3 and S4 are the same as in Example 1. The horizontal arrangement reduces the tank length, making it suitable for land-based modular equipment.

[0091] Example 4: A fourth combination of a high-efficiency coalescing separator device and separation method

[0092] 4.1 The fourth type of combination of devices

[0093] like Figure 16 As shown, the fourth combination, based on the third combination, replaces the combined fiber coalescing module 5 with a full-section combined fiber coalescing module 10, which is suitable for scenarios with a processing capacity of <150m³ / h and limited space height. The adaptive cyclone core tube 2 is arranged laterally, and the full-section module 10 replaces the plate structure; the air purging pipeline 6 is laid on the surface of the full-section combined fiber coalescing module 10.

[0094] The liquid inlet distribution pipe 11 ensures that the incoming liquid is evenly distributed in the lower part of the horizontal core tube. The remaining components are the same as in Example 3.

[0095] 4.2 Separation method for the fourth combination

[0096] Separation methods include:

[0097] S1. Preliminary separation of heavy oil: The incoming liquid is processed by the horizontally arranged adaptive cyclone core tube 2, and the steps are the same as in Example 3.

[0098] S2, Rectification and Preliminary Coagulation: After liquid phase rectification, it enters the next module.

[0099] S3, Deep demulsification and separation: The liquid phase enters the full-section combined fiber coalescence module 10; the ring distribution of the air purging pipeline 6 enhances the cleaning efficiency and prevents fiber blockage.

[0100] S4, Rapid coalescing and floating: Final separation. This combination saves height space and is suitable for compact platforms.

[0101] Example 5: A high-efficiency coalescing separator device and separation method of the fifth combination.

[0102] 5.1 The fifth combination of devices

[0103] like Figure 17 As shown, the main structure of the fifth combination is basically the same as that of the first combination. The core difference is that the adaptive cyclone core tube 2 is eliminated, and the incoming liquid directly enters the first-stage rapid separation module 3. The composition, position, and connection relationship of the remaining components are completely consistent with the first combination. It is suitable for working conditions where the oil phase density is <900kg / m³ and the oil content of the incoming liquid is <1000ppm, avoiding redundant design.

[0104] 5.2 Separation method for the fifth combination

[0105] This separation method is suitable for non-cyclone core tube designs:

[0106] S1. Preliminary separation of heavy oil: When the oil phase density is <900kg / m³ and the oil content is <1000ppm, the incoming liquid directly enters the first-stage rapid separation module 3, skipping the cyclone step.

[0107] S2-S4 are the same as in Example 1. The swirl function is omitted, reducing energy consumption and making it suitable for light oil applications.

[0108] Example 6, the sixth combination of a high-efficiency coalescing separator device and separation method

[0109] 6.1 The sixth combination of devices

[0110] like Figure 18 As shown, the sixth combination, based on the fifth combination (without adaptive cyclone core tube), replaces the combined fiber coalescing module 5 with a full-section combined fiber coalescing module 10, which is suitable for processing conditions with a throughput of <150m³ / h and low oil phase density. The air purging line 6 is laid on the surface of the full-section combined fiber coalescing module 10.

[0111] 6.2 Separation method for the sixth combination

[0112] This separation method is compatible with the sixth type of combined device:

[0113] S1. Preliminary oil-water separation: When the oil phase density is <900kg / m³ and the oil content of the incoming liquid is <1000ppm, the incoming liquid directly enters the first-stage rapid separation module 3, skipping the cyclone separation step.

[0114] S2, Rectification and Preliminary Coalescing: The liquid phase passes through the first-stage rapid separation module 3, where it undergoes rectification, distribution, and preliminary coalescence. The oil reservoir setting is determined based on the pressure difference and gas-liquid ratio (a gas reservoir is set when the pressure difference is >200 kPa or the gas-liquid ratio is ≥0.1), and the baffle combination is adjusted according to the properties of the incoming liquid.

[0115] S3, Deep Demulsification Separation: The liquid phase enters the full-section combined fiber coalescing module 10 for deep demulsification; this module is used when the unit's throughput is <150 m³ / h. The air purging pipeline 6 is operated periodically to remove impurities trapped in the fiber bed.

[0116] S4. Final separation: After the liquid phase is enhanced by the secondary coalescence separation module 7, the oil phase floats to the surface and flows into the oil tank, while the water phase is discharged from the outlet 8.

[0117] This method is suitable for small-volume, low-oil-density applications, has a compact structure, and low operating costs.

[0118] Example 7: A high-efficiency coalescing separator device and separation method of the seventh combination.

[0119] 7.1 The seventh combination of devices

[0120] like Figure 19 As shown, the seventh combination, based on the fifth combination (without adaptive cyclone core tube), eliminates the first oil pack 41, retaining only the second oil pack 4 at the end of the tank, suitable for conditions where the oil content at the inlet is <200ppm. The internal components of the tank are a primary rapid separation module 3, a combined fiber coalescing module 5 (parallel plate type), and a secondary coalescing separation module 7. Only the second oil pack 42 is located at the top of the tank. The inlet 1 is directly connected to the primary rapid separation module 3, simplifying the top structure of the tank by eliminating the primary oil pack. The combined fiber coalescing module 5 adopts a parallel plate structure, with the air purging line 6 arranged parallel between the plates. The sand removal line 9 and the water outlet 8 retain their original configurations.

[0121] 7.2 Separation Method for the Seventh Combination

[0122] This separation method is designed for low oil content operating conditions:

[0123] S1. Preliminary oil-water separation: When the oil phase density is <900kg / m³ and the oil content is <1000ppm, the incoming liquid directly enters the first-stage rapid separation module 3.

[0124] S2, Rectification and Preliminary Coagulation: After being processed by the first-stage rapid separation module 3, the liquid phase directly enters the subsequent modules; because the inlet oil content is <200ppm, the first-stage oil pack setting is omitted.

[0125] S3, Deep demulsification and separation: The liquid phase enters the combined fiber coalescence module 5, and the fiber bed is demulsified; the air purging pipeline 6 is maintained regularly.

[0126] S4. Final separation: After coalescing in the secondary coalescence module 7, the oil phase floats to the end oil pack 4, and the water phase is discharged from the outlet 8.

[0127] This method simplifies the oil pack structure and reduces equipment complexity.

[0128] Example 8: The eighth combination of a high-efficiency coalescing separator device and separation method

[0129] 8.1 The eighth combination of devices

[0130] like Figure 20 As shown, the eighth combination, based on the seventh combination, replaces the combined fiber coalescing module 5 with a full-section combined fiber coalescing module 10, suitable for processing conditions with a capacity <150m³ / h and an inlet oil content <200ppm. Only the second oil reservoir 42 is located at the end of the top of the tank. The full-section module 10 fills the entire tank cross-section, and the air purging pipeline 6 is laid on its surface, using a parallel or ring-shaped distribution.

[0131] 8.2 Separation method for the eighth combination

[0132] This separation method is suitable for low oil content and small throughput conditions.

[0133] S1. Preliminary oil-water separation: The incoming liquid directly enters the first-stage rapid separation module 3 (oil phase density <900kg / m³ and oil content <1000ppm).

[0134] S2, Rectification and Preliminary Coagulation: After liquid phase rectification, it enters the full-section module 10; because the inlet oil content is <200ppm, no first-stage oil pack is set.

[0135] S3, Deep demulsification and separation: Full-section combined fiber coalescing module 10 treats emulsified oil; air purging pipeline 6 enhances cleaning effect.

[0136] S4. Final Separation: The oil phase flows into the terminal oil pack 4, while the aqueous phase is discharged. This assembly has a simplified structure and is suitable for scenarios with strictly limited space.

[0137] Example 9: The ninth combination of a high-efficiency coalescing separator device and separation method

[0138] 9.1. The ninth combination of devices

[0139] like Figure 21As shown, the ninth combination, based on the eighth combination, eliminates the top oil reservoir 4 and replaces it with an oil collection chamber 13 at the rear of the tank. The original location of the second oil reservoir 42 on the top of the tank is now occupied by an outlet 45. The oil collection chamber 13 is an overflow weir plate structure, suitable for scenarios where space at the top of the tank is limited. The weir plate 12 is vertically installed at the bottom of the rear of the tank, with a height greater than two-thirds of the tank diameter. The oil collection chamber 13 is located behind the weir plate 12, and its bottom is connected to the oil outlet 14 via a pipe. The volume of the oil collection chamber 13 meets the oil phase residence time requirements.

[0140] 9.2 Separation method for the ninth combination

[0141] This separation method is compatible with tail-end oil collection structures:

[0142] S1-S3, the same as in Example 8, the incoming liquid is processed by the first-stage rapid separation module 3 and the full-section module 10.

[0143] S4. Final Separation: The oil phase rises above the weir plate 12 and enters the oil collection chamber 13, while the water phase flows out from the bottom outlet 8 at the front end of the weir plate. The oil phase is collected in the oil collection chamber 13 and discharged from the oil outlet 14. This method is suitable for special sites where oil packs cannot be installed at the top.

[0144] In summary, this invention, through nine combinations, covers various working conditions ranging from high-viscosity oil to low-oil content, large-volume processing to low-flow rate, and conventional to confined spaces, achieving efficient and compact oil-water separation.

[0145] Example 10: Application Verification of a Platform in a Bohai Oilfield (Heavy Oil)

[0146] The equipment in this embodiment processes 4500m³ of produced fluid. 3 / d, gas content 1.0×10 4 Sm 3 / d, oil phase density > 920 kg / m³ 3 (Heavy oil). Overall water content 99%, i.e., oil content 1000 mg / L, solid content approximately 300 mg / L. The specific processing procedure is as follows:

[0147] The produced fluid first enters an adaptive cyclone core tube for three-phase separation of oil, water, and gas. After separation, the liquid phase with an oil content of 500-1000 mg / L and a solid content ≤100 mg / L enters the combined fiber coalescing module through a rapid separation module from the bottom outlet. The combined fiber coalescing module facilitates rapid coalescence of oil droplets, causing emulsified oil droplets with a median particle size (D50) of 10-30 μm to collide and coalesce in the bed, eventually coalescing into larger oil droplets with a median particle size (D50) of 0.1-10 mm. These droplets float to the top outlet, and after demulsification, the liquid phase with an oil content <80 mg / L enters the coalescing separation module from the bottom outlet. The coalescing separation module achieves rapid separation of the oil and water phases. After treatment, the average oil content of the outlet aqueous phase is reduced to 50 mg / L, with a separation efficiency exceeding 95%; the solid content is reduced to below 40 mg / L.

[0148] The system operated continuously and stably for 30 days. During this period, when the throughput fluctuated within ±30%, all separation indicators remained stable and there was no significant decrease in efficiency. At the same time, the amount of demulsifiers and reverse demulsifiers used was reduced by 30% compared to the traditional inclined plate + air flotation process.

[0149] Application verification on the Bohai Oilfield platform shows that the staged separation device and method have a stable processing capacity for produced fluids with high water cut and heavy oil content. The separation efficiency at each stage remains above 90%, and the final reinjection water index fully meets industry standards. The system is highly adaptable to fluctuations in processing capacity and can significantly reduce reagent consumption, demonstrating its applicability and economic efficiency in the Bohai Sea area.

[0150] Example 11: Application Verification of a Platform in a Yellow Sea Oilfield (Light Oilfield)

[0151] In this embodiment, the project equipment processes 3200 m³ / d of produced fluid with a gas content of 1.5 × 10⁻⁶ m³ / d. 4 Sm³ / d, oil phase density < 850 kg / m³ (light crude oil). Overall water content 98%, i.e., imported oil content approximately 2000 mg / L, solid content approximately 200 mg / L. The specific treatment process is as follows:

[0152] After the produced fluid enters the system, it first passes through a combined fiber coalescing module, which utilizes the surface properties of special fiber materials to capture micro-emulsified oil droplets, promoting their coalescence and enlargement into larger oil droplets. Subsequently, the fluid enters a coalescing separation module, where, based on the oil-water density difference and fluid dynamics design, instantaneous stratification and rapid separation of the large oil droplets from the aqueous phase are achieved. After treatment, the average oil content in the outlet aqueous phase is reduced to below 30 mg / L, with a separation efficiency exceeding 98%; the solid content is reduced to below 20 mg / L.

[0153] The system operated continuously and stably for 30 days. During this period, the effluent quality remained stable and was not affected by flow fluctuations, even with a processing volume fluctuation of ±25%. Meanwhile, thanks to the improved physical coalescence efficiency, the dosage of chemical agents such as reverse demulsifiers was reduced by 25% compared to the original conventional gravity sedimentation + cyclone separation process.

[0154] Application verification on the South China Sea oilfield platform shows that this device can treat light oil produced fluids through a simplified process without the need for adaptive cyclone core tubes, and the treatment effect is stable. The entire unit occupies only 38% of the platform's original treatment system (traditional inclined plate oil separator + air flotation separator + walnut shell filter), and the annual operation and maintenance cost is reduced by 45% compared to the original system. The system has a compact structure, small footprint, and can effectively reduce reagent operating costs, demonstrating its applicability and economic advantages on the confined space platform in the South China Sea.

[0155] The above description is only a partial embodiment of the present invention and is not intended to limit the scope of the present invention. Various changes can be made to the above embodiments of the present invention. All simple and equivalent changes and modifications made based on the description of the present invention fall within the protection scope of the present invention. All aspects not described in detail in this invention are conventional technical content.

Claims

1. A high-efficiency coalescing separator assembly, characterized in that, include: A horizontal tank, wherein one end of the tank is provided with a liquid inlet and the bottom of the other end is provided with a water outlet; Inside the tank, along the direction of fluid flow, are arranged in sequence as follows: The first-stage rapid separation module is used to receive the incoming liquid and perform flow field rectification and initial coalescence of oil droplets. It includes a combination of parallel flow stabilizers, stepped flow guides, corrugated coalescing plates, corrugated flow guides, or non-uniform parallel plate assemblies. A composite fiber coalescing module, connected downstream of the primary rapid separation module, is used for deep demulsification of the liquid phase containing emulsified oil. The module is composed of oleophilic and hydrophobic fibers and hydrophilic and oleophobic fibers in proportion, and is equipped with an integrated air purging pipeline. A secondary coalescing separation module is connected downstream of the combined fiber coalescing module and is used for the final separation of oil and water; The tank has an oil bag at the top for collecting the separated oil phase and a sand removal pipeline at the bottom for removing deposited solids.

2. The apparatus according to claim 1, characterized in that, It also includes an adaptive cyclone core tube located upstream of the primary rapid separation module; the adaptive cyclone core tube consists of a main separation tube, a secondary separation tube and a connecting tube, and is arranged vertically or horizontally within the tank.

3. The apparatus according to claim 1, characterized in that, The single-tube capacity of the adaptive cyclone core is 5 m³ / h or 10 m³ / h, and the operating pressure drop is no greater than 0.2 MPa.

4. The apparatus according to claim 1, characterized in that, In the composite fiber coalescing module, the ratio of oleophilic and hydrophobic fibers to hydrophilic and oleophilic fibers is 3:7 to 7:3; for light oils, the proportion of oleophilic fibers is 60% to 70%; for heavy oils, the proportion of hydrophilic fibers is 60% to 70%.

5. The apparatus according to claim 4, characterized in that, The combined fiber coalescing module is a parallel plate structure, with the air purging pipeline laid in the flow channel between the plates; or, it is a full cross-section structure that fills the entire flow section of the tank, with the air purging pipeline laid on its surface.

6. The apparatus according to claim 1, characterized in that, The oil pack includes a first oil pack and a second oil pack. The first oil pack is located on top of the tank behind the first-stage rapid separation module, and the second oil pack is located on top of the tank behind the second-stage coalescing separation module. The first oil pack can be replaced with a gas pack equipped with a gas deliquescence module inside.

7. The apparatus according to claim 1, characterized in that, The sand removal pipeline consists of two parallel pipelines laid along the central axis of the bottom of the tank. Sand removal nozzles are installed on the pipelines with spray directions at 45° and 90° angles to the pipeline axis.

8. The apparatus according to claim 1, characterized in that, The stepped guide plates are arranged in the flow direction such that the width of the plates decreases step by step, or the height of the plates decreases step by step; or in the vertical direction, the density between the plates decreases from bottom to top.

9. A method for oil-water separation using the apparatus according to claims 1-8, characterized in that, Includes the following steps: S1. The oil-water mixture is passed through a primary rapid separation module to eliminate fluid turbulence and promote the collision and initial coalescence of oil droplets, resulting in a preliminarily separated oil phase and an aqueous phase containing emulsified oil. S2. The aqueous phase containing emulsified oil obtained in step S1 is passed through a combined fiber coalescence module, and the fiber bed is used to make the micro emulsified oil droplets coalesce and grow, resulting in a deeply demulsified liquid phase. S3. The liquid phase obtained after deep demulsification in step S2 is further coalesced and separated by a two-stage coalescing separation module to finally obtain a collectable oil phase and a water phase that meets the discharge or reuse standards. Before step S1, depending on whether the oil phase density of the incoming liquid is less than 900 kg / m³ and the oil content is less than 1000 ppm, the oil-water mixture is selectively pretreated by cyclone centrifugation through an adaptive cyclone core tube.

10. The method according to claim 9, characterized in that, In step S2, the air purging line is periodically activated to purge and regenerate the combined fiber coalescing module; and / or, depending on whether the device's processing capacity is less than 150 m³ / h, a combined fiber coalescing module with a parallel plate or full cross-section structure is selected.

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