Internal reverse rotation reforming coalescence separation method and separator

Abstract

The invention provides an internal reverse rotation reforming coalescence separation method and a separator. The cyclone separator is characterized in that a reverse rotation coalescence area is further arranged on the cyclone separator, and the reverse rotation coalescence area is formed by adopting a flow field with rotation direction difference generated by a tangential inlet and a tangential outlet of the cyclone separator; the tangential inlet and the tangential outlet are arranged along the tangential direction of the outer barrel of the cyclone separator barrel and are used for guiding fluid to enter or leave the cyclone separator barrel in a tangential manner; the reverse rotation coalescence area, the rotational flow area and the separation area work cooperatively, coalescence and reforming of dispersed phases with different particle sizes can be achieved, small-particle-size dispersed phases are promoted to be coalesced into large-particle-size dispersed phases, small-particle-size light dispersed phases are guided to the center of the coalescence separator, the rotation radius of the coalescence separator is reduced, and the radial migration force is enhanced. And the small-particle-size dispersed phase after reforming is promoted to be separated. According to the separation method and the separator for implementing the method, efficient separation of small-particle-size dispersed phases can be achieved, and the separation method and the separator are suitable for the fields of petroleum, chemical engineering, environmental protection, food and the like.

Description

Technical Field

[0001] This disclosure relates to a two-phase separation apparatus and method, specifically, to an apparatus and method capable of efficiently separating small-particle-size discrete phases. Background Technology

[0002] Oils mainly exist in four forms: floating oil, dispersed oil, emulsified oil, and dissolved oil. Floating oil and dispersed oil have relatively large droplet sizes and are easily removed by mechanical separation; however, emulsified oil, due to its smaller droplet size and the formation of a stable oil-in-water structure with water, is more difficult to separate. In the petrochemical industry, a large amount of oily wastewater is generated during production processes, with emulsified oil droplets typically ranging in size from 0.1 to 10 μm. Due to the small droplet size, surface charge, and presence of emulsifiers, the separation of these oil droplets presents a significant challenge.

[0003] With the advancement of the national sustainable development strategy and the increasing awareness of energy conservation and environmental protection, the treatment of oily wastewater has gradually received widespread attention, with the separation of emulsified oil being a key step in the treatment process. Currently, commonly used oil-water separation methods in the petroleum, chemical, and environmental protection fields include cyclone separation, air flotation, filtration, membrane separation, and collision and coalescence separation. Among these, air flotation has a limited adaptability to varying oil concentrations; while filtration can achieve efficient separation, it requires frequent backwashing when treating high-oil-content wastewater, making long-term stable operation difficult; membrane separation is costly and has strict requirements for media conditions. In contrast, cyclone separation is widely used due to its advantages such as simple structure, short processing time, high separation efficiency, small footprint, stable and continuous operation, and low cost. However, existing cyclone separators have poor separation performance for small-particle-size discrete phases during the separation process, a deficiency that limits the improvement of their overall separation efficiency.

[0004] To achieve efficient separation of small-diameter discrete phases, it is necessary to induce the coalescence of small-diameter oil droplets into larger-diameter droplets during the cyclone separation process, or to guide small-diameter particles or droplets to the center of the coalescing separator through flow field control, thereby increasing the radial force they experience. In summary, developing a novel cyclone separator and method that can significantly improve the separation efficiency of small-diameter discrete phases has become a critical issue urgently needing to be addressed in the petroleum, chemical, and related industries. Summary of the Invention

[0005] To address the aforementioned technical problems, this disclosure proposes an internal counter-rotating reforming coalescing separation method and apparatus. This apparatus, by setting tangential inlets and outlets in different directions and a spiral body, can achieve one or two forced counter-rotations of the flow field, that is, forcibly changing the flow field originally rotating in a certain direction (e.g., clockwise) to rotating in the opposite direction (e.g., counterclockwise). During the flow field counter-rotation process, the migration trajectories of discrete phases of different particle sizes intersect, thereby inducing coalescence. Simultaneously, after the flow field counter-rotation, small-diameter lightweight discrete phases are guided from large-radius regions to small-radius regions, while large-diameter lightweight discrete phases are guided to large-radius regions. Since large-diameter discrete phases are easier to separate, they can migrate back to small-radius regions in a short time, achieving reforming of the discrete phase particle size. This design can effectively promote the coalescence of small-diameter discrete phases into large-diameter discrete phases, and guide small-diameter particles or droplets to the center of the coalescing separator through flow field control, reducing their rotation radius and enhancing radial migration force, thereby promoting the rapid separation of the reformed small-diameter discrete phases. This innovative design enables efficient separation of mixtures and provides new ideas for optimizing the performance of other related separation equipment.

[0006] The technical solution and implementation steps adopted in this disclosure are as follows:

[0007] First, this disclosure proposes an internal anti-swirl reforming coalescence separation method, which includes setting a swirl zone and a separation zone on a swirl separator. Its unique feature is that:

[0008] An anti-swirl coalescence zone is also provided on the cyclone separator. The anti-swirl coalescence zone is formed by using a flow field with a swirl difference between the tangential inlet and the tangential outlet of the cyclone separator. The tangential inlet and the tangential outlet are both set along the tangential direction of the outer cylinder of the cyclone separator body to guide the fluid to enter or leave the cyclone separator body tangentially.

[0009] The anti-swirl coalescence zone, swirl zone, and separation zone work together to achieve coalescence and reforming of discrete phases with different particle sizes, promote the coalescence of small-particle-size discrete phases into large-particle-size discrete phases, guide the small-particle-size lightweight discrete phases to the center of the coalescence separator, reduce their rotation radius, enhance radial migration force, and promote the separation of the reformed small-particle-size discrete phases.

[0010] Furthermore, the flow field that generates the rotational difference is achieved by adjusting the tangential arrangement angle of the tangential inlet and tangential outlet.

[0011] Furthermore, with the tangential direction of the tangential inlet channel set to 0°, the tangential direction of the tangential outlet channel is set within the range of 0°-45° or 315°-360°, causing the direction of fluid rotation around the cylinder to be reversed.

[0012] To implement the aforementioned method, another aspect of this disclosure proposes an internal anti-swirl reforming coalescing separator, comprising a swirl zone, an anti-swirl coalescing zone, and a separation zone.

[0013] The separator includes a tangential inlet, a cylinder assembly, a tangential outlet, an annular overflow pipe, and a central overflow pipe.

[0014] The cylinder assembly is a hollow cylinder sealed with upper and lower end caps, including a first cylinder, a second cylinder and a third cylinder connected in sequence by flanges; the outer wall of the top of the first cylinder is tangentially connected to a tangential inlet, and the tangential inlet and the first cylinder together form a swirling zone to form a stable swirling field.

[0015] The top cover of the first cylinder is vertically connected to the center overflow pipe, and the bottom outer wall of the third cylinder is tangentially connected to the tangential outlet. Both the tangential inlet and the tangential outlet are arranged along the tangential direction of the outer cylinder of the cylinder to guide the fluid to enter or leave the cylinder in a tangential manner.

[0016] The tangential direction of the channel at the tangential inlet is set as the first swirling direction, and the tangential direction of the channel at the tangential outlet is set as the second swirling direction. The difference between the first and second swirling directions enables the flow fields generated at the tangential inlet and the tangential outlet to turn in opposite directions, resulting in forced reverse swirling of the flow field within the second cylindrical space, thereby forming a reverse swirling coalescence zone.

[0017] The annular overflow pipe, the central overflow pipe, the tangential outlet, and the third cylinder together constitute the separation zone, which is used to achieve efficient separation of the mixed phase.

[0018] Furthermore, the tangential direction of the channel at the tangential inlet is set to 0°, and the tangential direction of the channel at the tangential outlet is set within the range of 0°-45° or 315°-360°, so that the rotation direction of the fluid flowing in from the tangential inlet and out from the tangential outlet around the cylinder is reversed.

[0019] To further improve separation efficiency and adapt to more complex operating conditions, this disclosure provides an internal anti-spin reforming coalescence separator capable of achieving secondary anti-spin function, used to implement any of the aforementioned methods, as follows:

[0020] The separator includes a tangential inlet, a cylinder assembly, a tangential outlet, an annular overflow pipe, and a central overflow pipe;

[0021] The cylinder assembly is a hollow cylinder sealed with upper and lower end caps, including a first cylinder, a second cylinder and a third cylinder connected in sequence by flanges; the outer wall of the top of the first cylinder is tangentially connected to a tangential inlet, and the tangential inlet and the first cylinder together constitute a swirling zone to form a stable swirling field;

[0022] The top cover of the first cylinder is vertically connected to the center overflow pipe, and the bottom outer wall of the third cylinder is tangentially connected to the tangential outlet. Both the tangential inlet and the tangential outlet are arranged along the outer cylinder tangent direction of the cylinder to guide the fluid to enter or leave the cylinder tangentially.

[0023] The annular overflow pipe, the central overflow pipe, the tangential outlet, and the third cylinder together constitute the separation zone, which is used to achieve efficient separation of the mixed phase;

[0024] A fourth cylinder with a built-in helix is ​​connected between the first and second cylinders;

[0025] The spiral body has a circular ring structure at its center, with several blades extending uniformly from the outer edge of the ring and arranged in a spiral shape around the central axis. The spiral body and the cylinder assembly are arranged coaxially. The flow field generated by the spiral body is opposite to the flow field formed by the tangential inlet. The space after the fourth cylinder is connected to the first cylinder forms a primary coalescence anti-spinning zone.

[0026] The flow field direction generated at the tangential outlet is opposite to that of the flow field formed by the spiral body, and the space after the fourth cylinder is connected with the second and third cylinders forms a secondary coalescence anti-rotation zone.

[0027] Compared with the prior art, this disclosure has the following advantages and technical effects:

[0028] 1. By designing the tangential inlet and tangential outlet or by assisting with the direction of the spiral flow channel, the flow field can be reversed once or multiple times, forcibly changing the flow field that originally rotates in a certain direction (such as clockwise) to rotate in the opposite direction (such as counterclockwise), or rotate in the opposite direction again, thereby achieving the control of the flow field rotation direction.

[0029] 2. During the reverse flow process, discrete phases of different particle sizes will experience the convergence and change of their migration trajectories, which will lead to agglomeration. This process promotes droplet agglomeration, increases the collision probability of droplets of different sizes, transforms small droplets into large droplets, and provides favorable conditions for subsequent two-phase separation.

[0030] 3. During the flow field reversal process, small-diameter lightweight discrete phases are guided from large-radius regions to small-radius regions, while large-diameter lightweight discrete phases are guided to large-radius regions. Due to the larger radial migration force experienced by the large-diameter discrete phases, they can migrate back to small-radius regions in a short time, thereby achieving effective reshaping of the discrete phase particle size.

[0031] 4. By guiding small-diameter particles or droplets to the center of the coalescing separator, reducing their rotation radius and enhancing radial migration force, the small-diameter discrete phase after reforming is rapidly separated. This mechanism can achieve efficient separation of the mixture and provide a new design idea for the performance optimization of other related separation equipment.

[0032] 5. It can be simplified into an internal anti-rotation reforming coalescer through structural simplification. This simplified design effectively retains the core functions of the original device. The simplified device is suitable for scenarios that only require discrete phase coalescence and can meet the requirements for efficient coalescence under specific working conditions.

[0033] 6. This invention is applicable to the efficient separation of immiscible two phases. It features a simple structure and convenient installation, and has broad application prospects in petrochemical, environmental protection, and food industries. It can effectively improve the efficiency and economy of various separation processes. Attached Figure Description

[0034] The accompanying drawings, which form part of this disclosure, are used to provide a further understanding of this disclosure. The illustrative embodiments of this disclosure and their descriptions are used to explain this disclosure and do not constitute an undue limitation of this disclosure. In the drawings:

[0035] Figure 1 This is an overall view of an internal counter-rotating reforming coalescing separator;

[0036] Figure 2 This is a cross-sectional view of an internal reverse-spin reforming coalescence separator;

[0037] Figure 3 This is an overall view of a secondary internal counter-rotating reforming coalescing separator.

[0038] Figure 4 This is a cross-sectional view of a secondary internal reverse-rotation reforming coalescence separator;

[0039] Figure 5 This is a schematic diagram of the coalescence principle of an internal anti-spin reforming coalescing separator;

[0040] Figure 6 This is a schematic diagram of the coalescence principle of a secondary internal reverse-spin reforming coalescence separator;

[0041] Figure 7 This is a schematic diagram of the particle size reforming principle of an internal counter-rotating reforming coalescing separator;

[0042] Figure 8 This is a dimensional diagram of an internal counter-rotating reforming coalescing separator;

[0043] Figure 9 This is a dimensional diagram of a secondary internal reverse-spin reforming coalescence separator;

[0044] Figure 10 This is a schematic diagram of an internal anti-rotation reforming coalescer.

[0045] Figure 11 This is an overall view of the spiral flow channel.

[0046] Figure 11-1 This is a top view of the spiral flow channel;

[0047] Figure 11-2 This is a top sectional view of the spiral flow channel;

[0048] Figure 11-3 This is a right-side sectional view of the spiral flow channel;

[0049] Figure 12 The diagram above the cylinder shows the installation configuration of the overflow pipe.

[0050] Figure 13 The diagram below shows the installation configuration of the overflow pipe;

[0051] Figure 14 A diagram showing a cylindrical structure.

[0052] Figure 14-1 This is a diagram illustrating a cylindrical structure with a cylindrical upper section and a conical lower section.

[0053] Figure 14-2 This is a diagram illustrating a cylindrical structure with a cylindrical upper section and a lower arc shape.

[0054] Figure 14-3 A diagram showing a conical cylindrical structure;

[0055] In the diagram: 01-Swirl zone, 02-Anti-swirl coalescence zone, 03-Separation zone, 04-Primary coalescence anti-swirl zone, 05-Secondary coalescence anti-swirl zone, 101-Tangential inlet, 102-Cylinder, 102-1-First cylinder, 102-2-Second cylinder, 102-3-Third cylinder, 102-4-Fourth cylinder, 103-Spiral, 104-Tangential outlet, 105-Central overflow pipe, 106-Flange, 107-Annular overflow pipe. Detailed Implementation

[0056] The technical solution presented in this disclosure will be described in detail below with reference to the accompanying drawings:

[0057] like Figures 1-4 The diagram shows a structural schematic of a separator using the method described in this disclosure. The separator comprises a tangential inlet 101, a cylinder 102, a spiral 103, a tangential outlet 104, a central overflow pipe 105, and an annular overflow pipe 107. Figure 1 , Figure 3 As shown, the cylinder 102 is a hollow cylinder with sealed upper and lower end caps, and it is a multi-segment combination. The cylinders are connected by flanges 106, and the outer wall of its top end is tangentially connected to the tangential inlet 101.

[0058] The tangential inlet 101 and the first cylinder 102-1 together constitute the vortex zone 01, such as Figure 5 , Figure 6It is used to form a stable swirling field; the top cover plate of the cylinder 102 is vertically connected to the center overflow pipe 105 and the annular overflow pipe 107, and the bottom outer wall of the cylinder is tangentially connected to the tangential outlet 104. The tangential inlet 101 and the tangential outlet 104 are both set along the outer cylinder tangent direction of the cylinder 102 to guide the fluid to enter or leave the cylinder in a tangential manner.

[0059] like Figure 1 As shown, the tangential inlet 101 is located in the first cylinder 102-1, and its channel tangential direction is set to a first rotation direction (e.g., clockwise); while the tangential outlet 104 is located in the third cylinder 102-3, and its channel tangential direction is set to a second rotation direction (e.g., counterclockwise) opposite to that of the tangential inlet 101. The aforementioned rotation direction difference can be achieved by adjusting the tangential arrangement angle of the inlet and outlet. Preferably, the tangential direction of the tangential inlet channel is set to 0°. If the rotation direction remains unchanged, the outlet direction should be set to 180°. However, this device sets the tangential direction of the tangential outlet channel to 0°-45° or 315°-360°, causing the fluid rotation direction around the cylinder to reverse. This angle setting can be optimized and adjusted according to the specific structural dimensions of the separator and the fluid characteristics. The flow field direction generated by the tangential outlet 104 is opposite to that generated by the tangential inlet 101. The annular overflow pipe 107, the central overflow pipe 105, the tangential outlet 104, and the third cylinder 102-3 together constitute the separation zone 03, which is used to achieve efficient separation of the mixed phase. Since the flow field direction generated by the tangential inlet 101 and the tangential outlet 104 is opposite, a forced reverse flow will occur in the second cylinder 102-2, thereby forming a reverse flow coalescence zone 02. This zone can effectively realize the coalescence and reforming of discrete phases with different particle sizes, greatly improve the separation efficiency of small particle size discrete phases, and provide a simpler and more efficient solution for the separation process.

[0060] In application, oil and water phases with a certain density difference enter the coalescing separator cylinder 102 through the tangential inlet 101 and rotate at high speed along the cavity wall. Under the action of centrifugal force, the less dense oil droplets gather towards the inner side of the swirling field and gradually flow out through the annular overflow pipe 107. However, due to the small difference in centrifugal force between the small-diameter oil droplets and water, these small oil droplets are still distributed on the outer side of the swirling field and continue to move downward with the mixture. Since the flow field generated by the tangential outlet 104 and the tangential inlet 101 has opposite directions, a change in flow field direction occurs in the middle space of the cylinder. During this process, oil droplets of different sizes will experience the convergence and change of their migration trajectories, causing collisions between the oil droplets. After the collision, the oil film of the oil droplets breaks, forming larger oil droplets. At the same time, due to the change in the swirling direction of the flow field, small-diameter oil droplets are guided from the large-radius region to the small-radius region. In the small-radius region, the rotation radius of the small oil droplets decreases, the radial migration force increases, and they are thus more easily transported to the axis of the swirling field. Larger oil droplets are guided to a larger radius region, and due to the greater radial migration force they experience, they can quickly migrate back to a smaller radius region. Ultimately, oil droplets of different sizes converge at the axis of the swirling flow field and gradually flow out through the top central overflow pipe 105. Simultaneously, the aqueous phase remains distributed on the outer side of the swirling flow field and flows out through the tangential outlet 104 on the bottom side, thus achieving highly efficient oil-water separation.

[0061] For the aforementioned internal reverse-spin reforming coalescing separator, the following modification scheme is proposed to achieve a secondary reverse-spin function: [e.g., ...] Figure 6As shown, a spiral 103 is installed within the anti-spin coalescing zone 02. The spiral 103 has a central ring structure with several blades extending uniformly from the outer edge of the ring and arranged spirally around the central axis. The spiral 103 is coaxially arranged with the cylinder assembly 102, and the flow field generated by the spiral 103 is opposite to the flow field formed by the tangential inlet 101. During this process, oil droplets of different sizes collide and coalesce, and the droplet size is reorganized. The coalesced oil droplets continue to move downwards and enter the spiral 103. Due to the small space inside the spiral 103, oil droplets of different sizes will further collide and coalesce here, and at the same time, oil droplets of different sizes will remix. The space after the fourth cylinder 102-4 is connected to the first cylinder 102-1 forms a primary coalescing anti-spin zone 04. The flow field direction generated by the tangential outlet 104 is opposite to that generated by the spiral 103. The space formed after the fourth cylinder 102-4 connects with the second cylinder 102-2 forms a secondary coalescence and anti-swirl zone 05. During the secondary anti-swirl process, oil droplets continue to collide and coalesce, and the droplet size is reshaped again. Finally, oil droplets of different sizes converge at the axis of the swirling flow field and are gradually discharged through the top central overflow pipe 105. At the same time, the water phase is always distributed on the outside of the swirling flow field and is discharged through the tangential outlet 104 on the bottom side. Through the design of two anti-swirls, the coalescence and separation efficiency of oil droplets is effectively enhanced, thereby achieving more efficient oil-water separation.

[0062] This type of internal counter-rotating reforming coalescing separator can be simplified and converted into an internal counter-rotating reforming coalescing separator as follows: Figure 10 As shown, the feature is that, based on the structure, the overflow pipe 105 is removed and the upper end cover of the cylinder 102 is designed as a completely sealed structure, thereby forming a single-outlet design. This simplified design effectively retains the core function of the original device. By removing the overflow channel, it is suitable for scenarios where only discrete phase coalescing is required, and can meet the demand for efficient coalescing under specific working conditions.

[0063] like Figure 12 , Figure 13 As shown, the annular overflow pipe 107 and the central overflow pipe 105 can be installed in several ways: First, the annular overflow pipe 107 and the central overflow pipe 105 are vertically installed at the top center of the cylinder 102 and extend into the cylinder 102 to a certain depth; second, the central overflow pipe 105 is vertically installed at the top center of the cylinder 102 and communicates with the middle pipe of the spiral 103; third, the annular overflow pipe 107 and the central overflow pipe 105 are vertically installed at the bottom center of the cylinder 102, forming a co-current outflow with the tangential outlet 104.

[0064] The cylindrical body 102 can have several structural forms: cylindrical, cylindrical with a conical lower section, cylindrical with a conical lower section, single conical, or multi-conical, such as... Figure 14 , 14-1As shown in 14-2 and 14-3.

[0065] The main parameters and preferred dimensions of the preferred embodiment are given below:

[0066] D1—the diameter of the overflow pipe, which is also the inner diameter of the spiral body, D1=(0.1~0.95)D3;

[0067] D2—Main diameter of the annular overflow pipe;

[0068] D3—Main diameter of the coalescing separator, determined based on the physical properties of the separated medium and the inlet flow rate;

[0069] L1—Overall length of the coalescing separator, L1=(1~200)D3;

[0070] L2—Overflow pipe insertion length, L2=(0~3)D3;

[0071] L3, L7—Overflow pipe lengths, L3 = (0.1~0.9)L1;

[0072] L4—Distance from the top of the hydrocyclone to the first flange;

[0073] L5—Distance between the two flanges;

[0074] L6—Length of the annular overflow pipe extending into the pipe;

[0075] L8—Pitch of the helical structure, L8=(1~2.5)D 3；

[0076] L9—thickness of the helical blade, L9 = (0.5~0.9)(D3-D1);

[0077] α—Helical blade angle, α = 10°~80°

[0078] β—helix angle, β s =10°~80°

[0079] k—Number of spiral flow channels, k=3~15;

[0080] L—Arch length of the helical blade, determined based on the number of helical flow channels k and the blade angle β;

[0081] A—Tangential inlet height; A = (0.05~1)D²;

[0082] B—Tangential inlet width; B=Q / (v×A), where Q is the throughput (volume flow rate) of the coalescing separator, and v is the inlet velocity of the coalescing separator, both in international standard units;

[0083] C—Tangential exit height;

[0084] D—Tangential exit height.

[0085] In this embodiment, the path of the oil droplet's counter-rotation can be described by a segmented helix, taking an initial flow field of clockwise rotation as an example. Within the swirling region 01, the oil droplet rotates clockwise, and its path is as follows:

[0086] z1(θ) = r1·θ·tanβ1

[0087] After passing through the anti-rotation coalescence region 02, the oil droplets switch to anti-rotation rotation, and their path is as follows:

[0088] z2(θ)=-r2·(θ-θ1)·tanβ2+z1(θ1)

[0089] Wherein, θ is the polar angle variable, representing the angle of rotation of the oil droplet around the central axis; r1 and r2 are the forward and reverse rotation radii, respectively; β1 and β2 are the forward and reverse spiral angles, respectively; θ1 is the polar angle of the reverse rotation switching point, representing the ending angle of the first reverse rotation. Preferably, the polar angle of the reverse rotation switching point θ1 is π to 2π, that is, the oil droplet particles flow out from the reverse rotation coalescing region after completing half to one rotation in the last rotation path.

[0090] During cyclone separation, dispersed oil droplets in the continuous phase are affected by multiple forces, including shear force, centrifugal force, and radial migration force. Particularly in the anti-cyclone coalescence region 02, the flow trajectories of the oil droplets intersect, creating a high probability of collision. Let the diameters of the two oil droplets be d1 and d2, and their relative velocity in the shear flow field be v. rel According to Smoluchowski's theory of coalescence, the number of collisions occurring per unit volume per unit time can be expressed as:

[0091] N C =K·C1·C2

[0092] Where C1 and C2 are the number concentrations of the two oil droplet sizes that collided, respectively; K is the collision kernel function, reflecting the frequency of collisions between oil droplets of different sizes in a given flow field, and is calculated using the following formula:

[0093] K = π(d1 + d2) 2 ·v rel

[0094] Furthermore, the actual number of collisions that can successfully coalesce depends on the coalescing efficiency E. c， The number of aggregations per unit time is:

[0095] N coalesce =E c ·N c =E c ·K·C1·C2

[0096] Cohesion efficiency Ec The following factors influence the flow: relative velocity between oil droplets; relative contact area between oil droplets; intensity and duration of flow field disturbance.

[0097] In the anti-spin coalescence region 02 of the present invention, the flow field fluctuations caused by the reversal of the spin direction can improve v rel This also increases the relative contact area between droplets, thereby increasing the collision frequency K, and within a certain shear rate range, it also helps to increase E. c This causes small-diameter oil droplets to rapidly coalesce into larger droplets. Furthermore, due to particle size reconstruction, the coalesced oil droplets are guided to a small radius within the swirling field, where their radial migration velocity v... r The increased volume allows oil droplets to quickly enter the separation channel and be discharged, thus completing the efficient oil-water separation process.

[0098] The proposed secondary internal counter-rotation reforming coalescing separation structure with an embedded helix is ​​intended to further achieve efficient coalescing and reforming of small-diameter discrete phases. In this structure, immiscible two-phase treatment liquids with a certain density difference (taking oil-water two-phase treatment liquid as an example) enter the coalescing separator cylinder 102 through the tangential inlet 101 and rotate at high speed along the cavity wall. Under the action of centrifugal force, the less dense oil droplets aggregate towards the inner side of the swirling flow field and gradually flow out through the overflow annular pipe 107. However, due to the small difference in centrifugal force between the small-diameter oil droplets and water, these small oil droplets remain distributed on the outer side of the swirling flow field and continue to move downwards with the mixture. Since the flow field generated by the helix 103 and the tangential inlet 101 has opposite directions, the first change in flow field direction occurs in the primary counter-rotation coalescing zone 04. During this process, oil droplets of different sizes collide and coalesce, and the droplet size is reformed. The coalesced oil droplets continue to move downwards and enter the spiral 103. Due to the small space inside the spiral 103, oil droplets of different sizes will further collide and coalesce, while simultaneously remixing. The flow field of the spiral 103 and the tangential outlet 104 rotates in opposite directions, causing a secondary counter-rotation within the secondary counter-rotation coalescing zone 05. During this secondary counter-rotation, oil droplets continue to collide and coalesce, further reshaping their size. Ultimately, oil droplets of different sizes converge at the axis of the swirling flow field and gradually discharge through the top central overflow pipe 105. Meanwhile, the aqueous phase remains distributed on the outer side of the swirling flow field and is discharged through the tangential outlet 104 on the bottom side. This double counter-rotation design effectively enhances the coalescence and separation efficiency of oil droplets, thus achieving more efficient oil-water separation.

[0099] In this embodiment, the first reverse swirl is formed by the difference in swirl direction between the tangential inlet 101 and the outlet of the spiral 103. That is, after the fluid enters from the tangential inlet, its original swirl direction deflects from the direction of the guide channel when it enters the spiral 103 flow guiding structure, forming a first reverse swirl coalescence zone 04. The second reverse swirl is formed by the opposite swirl direction between the outlet of the spiral 103 and the tangential outlet 104. After the fluid passes through the spiral 103, its flow direction is forced to change again, forming a second reverse swirl coalescence zone 05. Through the above two-stage swirl transformation design, two coalescence enhancement zones can be constructed sequentially inside the structure, allowing the small-particle-size discrete phase to undergo multiple coalescence and reconstruction in the continuous phase, effectively promoting particle size reforming and accelerated separation, and improving the overall separation efficiency.

[0100] Taking the helical body 103 with four helical flow channels as an example, the fluid particles in each flow path will experience one and two counter-rotations within the structure. The first path involves the fluid entering the device from the tangential inlet 101, forming a continuous and stable initial swirling field within the swirling region 01. The particle trajectory can be represented in cylindrical coordinates as follows:

[0101] z1(θ) = r1·θ·tanβ1

[0102] The second path segment represents the flow path of the fluid after the first reverse rotation. At this point, the fluid is guided into four sub-channels (k = 0, 1, 2, 3) and continues to move in a spiral direction. Since the spiral channels are uniformly distributed in space, the path in cylindrical coordinates needs to be corrected by angular offsetting the polar angle variable. The expression for the polar angle variable is:

[0103]

[0104] Where 2π is the path termination angle.

[0105] The path trajectory for the k-th channel is as follows:

[0106]

[0107] Where: θ1 k The angle represents the termination angle of the first counter-rotation, i.e., the starting angle in each channel; r2 is the rotation radius of the corresponding channel segment; and α is the helical lift angle.

[0108] The third path is the guide path where the fluid reverses its rotation direction again. Corresponding to the k-th channel, its trajectory is:

[0109]

[0110] Where: θ2 kThe angle representing the termination of the second counter-rotation is r3, the radius of rotation for the third segment is r3, and the angle of ascent is β3. This design, through a three-segment path model, forms a continuous flow-guiding, dual-counter-rotation particle size reforming mechanism, significantly improving aggregation efficiency and separation performance.

[0111] The collision-agglomeration mechanism during anti-rotation is the same as before.

[0112] The above are merely preferred embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A method for separating coalescing coalesces through internal counter-swirling reforming, comprising setting a swirling zone and a separation zone on a cyclone separator, characterized in that: An anti-swirl coalescence zone is also provided on the cyclone separator. The anti-swirl coalescence zone is formed by using a flow field with a swirl difference between the tangential inlet and the tangential outlet of the cyclone separator. The tangential inlet and the tangential outlet are both set along the tangential direction of the outer cylinder of the cyclone separator body to guide the fluid to enter or leave the cyclone separator body tangentially. The anti-swirl coalescence zone, swirl zone, and separation zone work together to achieve coalescence and reforming of discrete phases with different particle sizes, promote the coalescence of small-particle-size discrete phases into large-particle-size discrete phases, guide the small-particle-size lightweight discrete phases to the center of the coalescence separator, reduce their rotation radius, enhance radial migration force, and promote the separation of the reformed small-particle-size discrete phases.

2. The method for separating coalescing from internal anti-rotation reforming according to claim 1, characterized in that: The flow field that generates the rotational difference is achieved by adjusting the tangential arrangement angle between the tangential inlet and the tangential outlet.

3. The method for separating coalescing from internal anti-rotation reforming according to claim 2, characterized in that: With the tangential direction of the tangential inlet channel set at 0°, the tangential direction of the tangential outlet channel is set within the range of 0°-45° or 315°-360°, causing the direction of fluid rotation around the cylinder to be reversed.

4. An internal counter-rotating reforming coalescing separator, used to implement any one of the methods described in claims 1 to 3, characterized in that: It includes a swirling zone (01), an anti-swirling coalescence zone (02), and a separation zone (03); The separator includes a tangential inlet (101), a cylinder assembly (102), a tangential outlet (104), an annular overflow pipe (107), and a central overflow pipe (105); The cylindrical assembly (102) is a hollow cylinder sealed with upper and lower end caps, including a first cylinder (102-1), a second cylinder (102-2), and a third cylinder (102-3) connected in sequence by flanges; the outer wall of the top end of the first cylinder (102-1) is tangentially connected to a tangential inlet (101), and the tangential inlet (101) and the first cylinder (102-1) together constitute a swirling zone (01) for forming a stable swirling field; The top cover of the first cylinder (102-1) is vertically connected to the center overflow pipe (105), and the bottom outer wall of the third cylinder (102-3) is tangentially connected to the tangential outlet (104). The tangential inlet and the tangential outlet are both set along the outer cylinder tangent direction of the cylinder to guide the fluid to enter or leave the cylinder in a tangential manner. The tangential direction of the channel at the tangential inlet is set as the first swirling direction, and the tangential direction of the channel at the tangential outlet is set as the second swirling direction. There is a swirling direction difference between the first swirling direction and the second swirling direction, which can cause the flow fields generated by the tangential inlet (101) and the tangential outlet (104) to turn in opposite directions, and force the flow field to reverse in the space of the second cylinder (102-2), thereby forming a reverse swirling coalescence zone (02). The annular overflow pipe, the central overflow pipe, the tangential outlet, and the third cylinder (102-3) together constitute the separation zone (03), which is used to achieve efficient separation of the mixed phase.

5. An internal counter-rotating reforming coalescing separator according to claim 4, characterized in that: The tangential direction of the channel at the tangential inlet is set to 0°, and the tangential direction of the channel at the tangential outlet is set within the range of 0°-45° or 315°-360°, so that the rotation direction of the fluid flowing in from the tangential inlet and out from the tangential outlet around the cylinder is reversed.

6. An internal counter-rotating reforming coalescing separator for implementing any one of the methods described in claims 1 to 3, characterized in that: The separator includes a tangential inlet (101), a cylinder assembly (102), a tangential outlet (104), an annular overflow pipe (107), and a central overflow pipe (105); The cylindrical assembly (102) is a hollow cylinder sealed with upper and lower end caps, including a first cylinder (102-1), a second cylinder (102-2), and a third cylinder (102-3) connected in sequence by flanges; the outer wall of the top end of the first cylinder (102-1) is tangentially connected to a tangential inlet (101), and the tangential inlet (101) and the first cylinder (102-1) together constitute a swirling zone (01) for forming a stable swirling field; The top cover of the first cylinder (102-1) is vertically connected to the center overflow pipe (105), and the bottom outer wall of the third cylinder (102-3) is tangentially connected to the tangential outlet (104). The tangential inlet and the tangential outlet are both set along the outer cylinder tangent direction of the cylinder to guide the fluid to enter or leave the cylinder in a tangential manner. The annular overflow pipe, the central overflow pipe, the tangential outlet, and the third cylinder (102-3) together constitute the separation zone (03), which is used to achieve efficient separation of the mixed phase; Between the first cylinder (102-1) and the second cylinder (102-2), a fourth cylinder (102-4) with a built-in spiral (103) is connected; The spiral (103) has a circular ring structure at its center, with several blades extending uniformly from the outer edge of the ring and arranged in a spiral shape around the central axis. The spiral (103) is coaxially arranged with the cylinder assembly (102). The flow field generated by the spiral is opposite to the flow field formed by the tangential inlet (101). The space after the fourth cylinder (102-4) is connected to the first cylinder (102-1) forms a primary coalescence anti-rotation zone (04). The flow field generated by the tangential outlet (104) turns in the opposite direction to the flow field generated by the spiral body (103). The space after the fourth cylinder (102-4) is connected with the second cylinder (102-2) and the third cylinder (102-3) forms a secondary coalescence anti-rotation zone (05).

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