A forced circulation evaporator and its vapor-liquid separation structure

Abstract

The application discloses a forced circulation evaporator and a vapor-liquid separation structure thereof. The vapor-liquid separation structure comprises at least two levels of deflection assemblies, which are sequentially arranged between an evaporation chamber and a steam outlet along an axial direction of the evaporation chamber, and a first preset interval is kept between any two adjacent deflection assemblies along the axial direction of the evaporation chamber to form a corresponding steam buffer space. Each deflection assembly comprises a first deflection member and a second deflection member. The first deflection member is arranged to guide liquid-containing steam to form radial or circumferential flow. The second deflection member is arranged to guide the liquid-containing steam to a next deflection assembly or the steam outlet along a preset path, and change the flow direction of the liquid-containing steam, so that the liquid-containing steam forms a turning path between the two adjacent deflection assemblies. The technical scheme can improve the problem that the existing vapor-liquid separation structure has insufficient separation efficiency and liquid phase entrainment at the steam outlet under high load working conditions due to a single separation path.

Description

Technical Field

[0001] This application relates to the field of evaporation and separation technology, and more specifically, to a forced circulation evaporator and its vapor-liquid separation structure. Background Technology

[0002] In related technologies, forced circulation evaporators are widely used in the manufacture of specialized environmental protection equipment for water pollution control, solid waste pollution control, heavy metal pollution control, and nuclear pollution prevention, as well as in industrial fields such as high-salt wastewater treatment and chemical material concentration. Their working principle involves a circulating pump forcing the material to circulate between the heating chamber and the evaporation chamber. In the evaporation chamber, the material is heated and boils, generating liquid-containing vapor. To prevent the vapor from carrying liquid droplets that could affect subsequent processes or contaminate the condensate, a vapor-liquid separation structure is typically installed at the top of the evaporation chamber, before the steam outlet. Existing conventional vapor-liquid separation structures are mostly simple wire mesh demisters or baffles. However, when treating high-salt, high-viscosity, easily foaming materials, as well as waste liquids containing heavy metals, radioactive nuclides, or other pollutants, the high steam rise rate and large amount of entrained droplets render single separation structures inadequate. On the one hand, wire mesh is easily clogged by high-salt droplets or causes secondary entrainment, leading to a sharp decline in separation efficiency. On the other hand, simple baffles rely on only a single impact for separation, with minimal change in airflow direction, making it difficult for droplets to be effectively detached under inertial forces, ultimately resulting in severe liquid entrainment at the steam outlet. This not only reduces steam quality but also causes scaling and corrosion in downstream pipelines and equipment, affecting the long-term stable operation of the entire evaporation system. Therefore, there is an urgent need for a vapor-liquid separation structure with higher separation efficiency and the ability to adapt to high-load operating conditions. Summary of the Invention

[0003] The purpose of this application is to provide a forced circulation evaporator and its vapor-liquid separation structure, which aims to improve the problem that the existing vapor-liquid separation structure has insufficient separation efficiency under high load conditions and is prone to liquid phase entrainment at the steam outlet due to the single separation path.

[0004] To achieve this objective, this application provides a vapor-liquid separation structure for a forced circulation evaporator. The forced circulation evaporator is provided with an evaporation chamber and a steam outlet. The vapor-liquid separation structure includes at least two stages of baffle assemblies. These at least two stages of baffle assemblies are sequentially arranged along the axial direction of the evaporation chamber between the evaporation chamber and the steam outlet. Any two adjacent stages of baffle assemblies maintain a first preset distance along the axial direction of the evaporation chamber to form a corresponding steam buffer space. Each baffle assembly includes a first baffle element and a second baffle element. The first baffle is fixed in the evaporation chamber and is configured to guide the liquid vapor to form a radial or circumferential flow; The second baffle is fixed in the evaporation chamber and located downstream of the first baffle. It is configured to guide the liquid-containing vapor to the next stage baffle assembly or the steam outlet according to a preset path, and to change the flow direction of the liquid-containing vapor so that the liquid-containing vapor forms a reversal path between two adjacent stages of the baffle assembly.

[0005] Optionally, in some embodiments of this application, the first baffle is an annular guide plate, which is continuously arranged along the circumference of the evaporation chamber. The inner edge of the annular guide plate encloses a central channel for the liquid vapor to pass through. The outer edge of the annular guide plate is sealed and fixed to the inner wall of the evaporation chamber. The plate surface of the annular guide plate is inclined or horizontally arranged relative to the axial direction of the evaporation chamber, so as to guide the rising liquid vapor in a radial flow or circumferential swirling manner toward the central channel or the inner wall of the evaporation chamber.

[0006] Optionally, in some embodiments of this application, the surface of the annular guide plate gradually slopes upward from the inner wall of the evaporation chamber toward the center, and the slope angle is 5° to 45°; and / or, The inner edge of the annular guide plate is provided with a guide flange or serrated structure for breaking up large-diameter liquid droplets in the liquid vapor.

[0007] Optionally, in some embodiments of this application, the second baffle is a conical baffle or an arc-shaped baffle cap, which is disposed directly above the central channel, and the conical baffle or the arc-shaped baffle cap maintains a second preset distance from the corresponding annular guide plate in the axial direction of the evaporation chamber, so as to form a preset baffle gap between the annular guide plate and the conical baffle or the arc-shaped baffle cap for the liquid vapor to deflect and pass through.

[0008] Optionally, in some embodiments of this application, the angle between the generatrix of the conical baffle and the horizontal plane is 30° to 60°, or the radius of curvature of the arc-shaped baffle is 0.3 to 0.8 times the inner diameter of the evaporator chamber; and / or, The bottom edge diameter of the conical baffle or the arc-shaped baffle cap is larger than the inner edge diameter of the annular guide plate and smaller than the inner diameter of the evaporation chamber, so that the liquid vapor forms a reversible flow that diffuses from the center to the surrounding area when flowing through the preset baffle gap; and / or, The conical baffle or the arc-shaped baffle cap is fixedly connected to the inner wall of the evaporation chamber or to the upper surface of the annular guide plate by supporting ribs. The supporting ribs are arranged at intervals along the circumference of the evaporation chamber, and the width direction of the supporting ribs is parallel to the flow direction of the liquid-containing vapor to reduce resistance to the vapor flow; and / or, The top of the conical baffle or the arc-shaped baffle cap is also provided with a guide cone tip or a diversion boss. The guide cone tip or the diversion boss is configured to perform initial diversion of the liquid vapor rising to the central region of the second baffle, so as to reduce the direct impact load of the liquid vapor on the top of the second baffle.

[0009] Optionally, in some embodiments of this application, the number of the baffle components is three or four, and the first preset spacing between each baffle component increases progressively from bottom to top along the axial direction of the evaporation chamber to adapt to the gradient changes in the flow rate and liquid content of the liquid-containing vapor during its ascent.

[0010] Optionally, in some embodiments of this application, in two adjacent stages of the baffle assembly, the second baffle of the upper stage baffle assembly and the first baffle of the lower stage baffle assembly partially overlap in the axial direction of the evaporation chamber, so that the liquid vapor forms an S-shaped or Z-shaped return path between the two adjacent stages of the baffle assembly.

[0011] Optionally, in some embodiments of this application, the surface of the first baffle and / or the surface of the second baffle are provided with a hydrophobic coating or a micro / nano-structured hydrophobic layer, wherein the hydrophobic coating or the micro / nano-structured hydrophobic layer is configured to reduce the adhesion of droplets on the surface of the baffle and promote the rapid sliding off of droplets after aggregation; and / or, The first baffle and / or the second baffle are made of corrosion-resistant metal materials or high-temperature resistant engineering plastics; and / or, A liquid collection tank is provided on the lower side of the first baffle or on the outer edge of the second baffle. The liquid collection tank extends circumferentially along the evaporation chamber and is configured to collect the droplets separated by the baffle. The liquid formed by collecting the droplets is then guided back to the liquid pool at the bottom of the evaporation chamber through a liquid guide pipe; and / or, The vapor-liquid separation structure further includes a demister element disposed between the uppermost baffle assembly and the steam outlet. The demister element is at least one of a wire mesh demister, a cyclone demister, and a blade separator. The demister element is configured to perform final liquid-phase capture of the liquid-containing vapor after multi-stage baffle separation; and / or The vapor-liquid separation structure further includes a flow equalization distribution plate, which is located upstream of the baffle assembly closest to the bottom of the evaporation chamber. The flow equalization distribution plate is a perforated plate structure or a grid structure, and is configured to pre-uniformly distribute the liquid-containing vapor rising from the bottom of the evaporation chamber and intercept some large-diameter droplets.

[0012] Furthermore, to achieve this objective, this application embodiment also provides a forced circulation evaporator, which includes an evaporation chamber, a heating chamber, a circulation pump, and a vapor-liquid separation structure of any one of the above. The evaporation chamber has a steam outlet at its top, and the vapor-liquid separation structure is located in the top region of the evaporation chamber, above the boiling liquid surface of the evaporation chamber and below the steam outlet. The heating chamber is connected to the evaporation chamber through a circulation pipe, and the circulation pump is located on the circulation pipe.

[0013] Optionally, in some embodiments of this application, the forced circulation evaporator is a high-salt wastewater evaporation and crystallization device or a high-concentration organic waste liquid concentration device; and / or, The operating pressure of the evaporation chamber is -0.1MPa to 1.0MPa, the operating temperature of the evaporation chamber is 60℃ to 150℃, and the upward flow velocity of the liquid vapor is 0.5m / s to 5m / s.

[0014] The forced circulation evaporator and its vapor-liquid separation structure provided in this application employ at least two stages of baffle components arranged sequentially along the axial direction of the evaporation chamber. Each stage, through the cooperation of a first and a second baffle, forces the liquid-containing vapor to undergo multiple directional changes within a confined space, forming a multi-stage reversible flow path. This structural design effectively overcomes the shortcomings of related technologies, such as the easy clogging and secondary entrainment of single-wire demisters, and the low separation efficiency of simple baffles due to the small change in airflow direction. Specifically, the multi-stage reversible flow path allows droplets entrained in high-speed vapor to obtain multiple opportunities for inertial separation during repeated turning, significantly extending the droplet's travel distance and increasing its collision probability with the baffle components. Simultaneously, the vapor buffer space between adjacent baffle components can homogenize the flow velocity of the liquid-containing vapor after turning, avoiding secondary entrainment of separated droplets due to sudden changes in local flow velocity. This allows the droplets to gradually detach from the gas phase and fall back to the lower evaporation zone under the combined action of inertial force and gravity. Therefore, without relying on external power, this method effectively reduces the risk of liquid entrainment at the steam outlet under high-load operating conditions for high-salt, high-viscosity, or easily foaming materials, mitigates scaling and corrosion in downstream pipelines and equipment, and improves the long-term stability and reliability of the forced circulation evaporation system. It is evident that this technical solution effectively addresses the problems of insufficient separation efficiency and easy liquid entrainment at the steam outlet caused by the single separation path in existing vapor-liquid separation structures under high-load conditions. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] The structures, proportions, sizes, etc., shown in the accompanying drawings are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this application. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce.

[0017] Figure 1 This is a schematic diagram of the forced circulation evaporator according to an embodiment of this application; Figure 2 for Figure 1 A schematic cross-sectional view of the vapor-liquid separation structure of the forced circulation evaporator shown. Figure 3 for Figure 1 The diagram shows a second cross-sectional view of the vapor-liquid separation structure of the forced circulation evaporator. Figure 4 for Figure 1 The diagram shows a third cross-sectional view of the vapor-liquid separation structure of the forced circulation evaporator. Figure 5 for Figure 1 The diagram shows a fourth cross-sectional view of the vapor-liquid separation structure of the forced circulation evaporator.

[0018] Illustrations: 1. Forced circulation evaporator; 10. Vapor-liquid separation structure; 11. Baffle assembly; 111. First baffle; 1111. Central channel; 1112. Guide flange; 112. Second baffle; 1121. Guide cone tip; 113. Preset baffle gap; 114. Support rib; 12. Steam buffer space; 13. Demisting element; 14. Flow distribution plate; 20. Evaporation chamber; 21. Steam outlet; 30. Heating chamber; 40. Circulation pump; 50. Circulation pipe. Detailed Implementation

[0019] To make the inventive objectives, features, and advantages of this application more apparent and understandable, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] In the description of this application, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component centrally located at the same time.

[0021] The technical solution of this application will be further described below with reference to the accompanying drawings and specific embodiments.

[0022] Please see Figures 1 to 5 As shown, in one embodiment, this application provides a vapor-liquid separation structure 10 for a forced circulation evaporator 1. The forced circulation evaporator 1 is provided with an evaporation chamber 20 and a steam outlet 21. The vapor-liquid separation structure 10 includes at least two stages of baffle assemblies 11, which are sequentially arranged between the evaporation chamber 20 and the steam outlet 21 along the axial direction of the evaporation chamber 20. Any two adjacent stages of baffle assemblies 11 maintain a first preset distance along the axial direction of the evaporation chamber 20 to form a corresponding steam buffer space 12. Each baffle assembly 11 includes a first baffle element 111 and a second baffle element 112. The first baffle element 111 is fixed in the evaporation chamber 20 and is configured to guide the liquid-containing vapor to form radial or circumferential flow. The second baffle 112 is fixed in the evaporation chamber 20 and located downstream of the first baffle 111. It is configured to guide the liquid vapor to the next stage baffle assembly 11 or the steam outlet 21 according to a preset path, and change the flow direction of the liquid vapor so that the liquid vapor forms a reversal path between the two adjacent baffle assemblies 11.

[0023] It should be noted that the vapor-liquid separation structure 10 of this embodiment is mainly used in the manufacture of special environmental protection equipment for water pollution, solid waste pollution, air pollution, heavy metal pollution, and nuclear pollution prevention and control, as well as in scenarios requiring forced circulation evaporation processes such as high-salt wastewater evaporation and crystallization, high-concentration organic waste liquid concentration, chemical mother liquor recovery, and pharmaceutical waste liquid treatment. In these application scenarios, the boiling liquid level in the evaporation chamber 20 usually fluctuates significantly, and due to the high salinity, high viscosity, or easy foaming characteristics of the material itself, the secondary steam generated by boiling carries a large number of droplets or even foam, and the steam rises rapidly, requiring high processing capacity and separation accuracy from the separation structure. In this embodiment, the vapor-liquid separation structure 10 is located in the top region of the evaporation chamber 20, above the boiling liquid level and below the steam outlet 21, with liquid-containing steam entering the area where the vapor-liquid separation structure 10 is located from bottom to top. During the actual operation of the evaporation chamber 20, its operating pressure can be negative, normal, or positive, the operating temperature varies according to the boiling point of the material, and the rising velocity of the liquid-containing steam fluctuates depending on the operating conditions. The structure of this embodiment can perform multi-stage deflection processing of liquid vapor by relying solely on the spatial arrangement of the internal deflection assembly 11 without relying on external power.

[0024] In this embodiment, the number of baffle components 11 is at least two stages, but the specific number of stages can be reasonably selected according to the internal space height of the evaporation chamber 20, the steam flow rate, and the required separation efficiency. The more stages, the longer the return path and the more complete the separation effect, but the corresponding pressure drop will also increase. In practical applications, a balance can be achieved between separation efficiency and energy consumption. In addition, the first preset spacing between each stage of baffle components 11 can be adjusted according to the gradient changes in the flow rate and liquid content of the liquid-containing vapor during the rising process, so as to adapt to different material characteristics and operating conditions and ensure that the vapor-liquid separation structure 10 can maintain stable separation performance under a wide range of operating conditions.

[0025] Thus, the vapor-liquid separation structure 10 of this embodiment, through the above-described structural configuration, employs at least two stages of baffle components 11 arranged sequentially along the axial direction of the evaporation chamber 20. Each stage component, through the cooperation of the first baffle 111 and the second baffle 112, forces the liquid-containing vapor to undergo multiple directional changes within a limited space, forming a multi-stage reversible flow path. This structural configuration effectively overcomes the shortcomings of related technologies, such as the easy clogging and secondary entrainment of single-wire demisters, and the low separation efficiency of simple baffles due to the small change in airflow direction. Specifically, the multi-stage reversible flow path allows droplets entrained in high-speed vapor to obtain multiple opportunities for inertial separation during repeated turning processes, significantly extending the droplet's travel distance and increasing its collision probability with the baffle components. Simultaneously, the vapor buffer space 12 between adjacent baffle components 11 can homogenize the flow velocity of the liquid-containing vapor after turning, avoiding secondary entrainment of separated droplets due to sudden changes in local flow velocity, thereby allowing the droplets to gradually detach from the gas phase and fall back to the lower evaporation zone under the combined action of inertial force and gravity. Therefore, without relying on external power, the risk of liquid entrainment at the steam outlet 21 of high-salt, high-viscosity, or easily foaming materials under high-load operating conditions is effectively reduced, the scaling and corrosion trend of downstream pipelines and equipment is mitigated, and the long-term stability and reliability of the forced circulation evaporation system are improved.

[0026] In some examples, such as Figure 2 and Figure 5 As shown, the first baffle 111 is an annular guide plate. The annular guide plate is continuously arranged along the circumference of the evaporation chamber 20. The inner edge of the annular guide plate encloses a central channel 1111 through which liquid vapor passes. The outer edge of the annular guide plate is sealed and fixed to the inner wall of the evaporation chamber 20. The plate surface of the annular guide plate is inclined or horizontal relative to the axial direction of the evaporation chamber 20, so as to guide the rising liquid vapor to the central channel 1111 or the inner wall of the evaporation chamber 20 in a radial flow or circumferential swirling manner. Thus, when the rising liquid vapor enters the baffle assembly 11, it no longer maintains its original single axial upward state, but changes to radial or circumferential flow under the guidance of the annular guide plate. This initial change in flow direction causes some of the larger droplets entrained in the vapor to be thrown towards the inner wall of the evaporation chamber 20 or the surface of the annular guide plate due to inertial force during the turning process, thereby achieving primary separation. At the same time, the guided liquid vapor can enter the central channel 1111 in a more uniform distribution state, providing flow field conditions for the further separation of the subsequent second baffle 112, which is conducive to improving the separation efficiency of the entire baffle assembly 11.

[0027] It should be noted that in this example, the outer edge of the annular guide plate and the inner wall of the evaporation chamber 20 can be sealed and fixed by welding or flange connection to ensure that liquid vapor cannot directly short-circuit through the gap between the outer edge of the annular guide plate and the inner wall of the evaporation chamber 20. This ensures that all rising steam must change direction through the guiding effect of the annular guide plate before passing through the central channel 1111. The surface of the annular guide plate can be a complete annular solid plate, or a small number of balancing holes can be opened on the plate surface according to the actual steam flow rate to adjust the local pressure difference. The cross-sectional shape of the central channel 1111 is consistent with the inner edge shape of the annular guide plate, usually circular, and its diameter can be reasonably designed according to the inner diameter of the evaporation chamber 20 and the expected steam flow rate. In actual installation, the annular guide plate should be placed horizontally or installed precisely according to the designed tilt angle to ensure the accuracy and consistency of the guiding direction.

[0028] In some examples, such as Figures 2 to 5 As shown, the surface of the annular guide plate gradually slopes upwards from the inner wall of the evaporation chamber 20 towards the center, with an inclination angle of 5° to 45°. This inclination angle range provides a smooth and clear directional guidance for the liquid-containing vapor without creating excessive flow resistance, allowing the rising airflow to pre-adjust its direction before entering the central channel 1111. Simultaneously, compared to a horizontally arranged plate, the inclined plate allows droplets impacting and adhering to the plate surface to gain a driving force to slide down the plate surface under the influence of gravity, thereby accelerating the collection and fall of droplets towards the inner wall of the evaporation chamber 20. This effectively prevents droplets from remaining on the upper side of the plate surface for extended periods or being sheared and entrained again by subsequent rising steam, thus improving the stability and reliability of the separation effect of the baffle assembly 11 during long-term operation.

[0029] It should be noted that when the tilt angle is less than 5°, the surface of the annular guide plate is nearly horizontal. The component of the droplet's downward sliding force in the direction of gravity is too small to overcome the adhesion between the droplet and the plate surface. This causes the droplet to easily accumulate on the surface of the annular guide plate, forming a liquid film, which increases the risk of secondary entrainment. When the tilt angle is greater than 45°, the surface of the annular guide plate is too steep. Although this is conducive to droplet sliding, the flow resistance encountered by the liquid vapor as it flows over the plate surface increases significantly, the local pressure drop increases, and the change in airflow direction is too drastic. This easily forms a vortex zone on the lower side of the plate surface, causing some separated droplets to be re-entrained into the central channel 1111. Therefore, limiting the tilt angle to the range of 5° to 45° can achieve a good balance between droplet sliding effect and airflow performance. In practical engineering applications, the specific tilt angle can be optimized and determined based on parameters such as the rising velocity of liquid vapor, the average particle size of the droplets, and the viscosity of the material. For example, when processing high-viscosity materials, the tilt angle can be appropriately increased to enhance the droplet sliding effect.

[0030] In some examples, such as Figure 5 As shown, the inner edge of the annular guide vane is provided with a guide flange 1112 or a serrated structure (not shown) to break up large-diameter droplets in the liquid vapor. Thus, when the liquid vapor accelerates through the central channel 1111, the guide flange 1112 or serrated structure at the inner edge of the annular guide vane can locally cut, disturb, and accelerate the airflow, causing the large-diameter droplets entrained within to be broken into smaller droplets under shear and impact forces. This reduces the mass of the large-diameter droplets, lowers their inertia, and makes them easier to be carried by the airflow and change direction when they subsequently pass through the second baffle 112, thereby increasing the probability of collision between the droplets and the baffle wall and improving the overall droplet collection efficiency of the baffle assembly 11. Furthermore, the droplet breaking process releases some of the surface energy inside the droplets, making them more likely to coalesce and adhere after colliding with the baffle wall, reducing the elastic rebound of the droplets and further improving the separation effect.

[0031] It should be noted that the guide flange 1112 in this example can be specifically set as an annular folded edge structure that extends continuously along the inner edge of the annular guide plate. The folded edge can be folded upwards or downwards relative to the surface of the annular guide plate, and its folding angle is usually 90° to 180°. The width of the folded edge can be designed according to the diameter of the central channel 1111 and the steam flow rate, and is generally taken as 2% to 10% of the inner edge diameter. The serrated structure can be set as multiple tooth-shaped protrusions evenly distributed along the inner edge circumferentially. The tooth shape can be triangular, trapezoidal, or arc-shaped. The height of the teeth and the tooth spacing should be reasonably selected according to the expected droplet breaking effect and the allowable pressure drop increment. Usually, the tooth height is 3mm to 15mm and the tooth spacing is 5mm to 20mm. The guide flange 1112 or the serrated structure can be directly stamped and formed integrally with the annular guide plate, or it can be fixedly connected to the inner edge by welding or riveting. Its material should be the same as that of the annular guide plate to ensure consistent corrosion resistance in high temperature and high salt environment. In addition, when the number of large-diameter droplets entrained in the liquid vapor is small or the material itself is not prone to producing large-diameter droplets, the guide flange 1112 or serrated structure may not be set to simplify the manufacturing process and reduce costs. Therefore, this structure should be selectively set according to the actual working conditions.

[0032] In some examples, such as Figure 2 and Figure 3 As shown, the second baffle 112 is a conical baffle (i.e. Figure 2 (as shown in the diagram) or an arc-shaped deflector cap (i.e.) Figure 3As shown in the diagram, a conical baffle or an arc-shaped baffle cap is positioned directly above the central channel 1111, and the conical baffle or arc-shaped baffle cap maintains a second preset distance from the corresponding annular guide plate in the axial direction of the evaporation chamber 20, so as to form a preset baffle gap 113 between the annular guide plate and the conical baffle or arc-shaped baffle cap for the liquid-containing vapor to turn and pass through. In this way, the liquid-containing vapor, after being guided and accelerated through the central channel 1111 by the annular guide plate, is blocked by the solid wall when it rises to the bottom of the baffle or baffle cap, and is forced to turn radially outward. The flow direction changes from axial upward to radial or oblique diffusion, so that the liquid droplets entrained in the vapor cannot follow the gas phase to complete the sharp turn due to their own inertial force, and are thrown towards the bottom wall of the baffle or baffle cap and the inner wall of the evaporation chamber 20, achieving inertial impact separation. Meanwhile, the surface of the conical baffle or arc-shaped baffle cap is a smooth slope or arc, which allows the droplets after collision and separation to quickly converge along the wall and slide down to the edge to drip, effectively reducing the residence time of droplets on the surface of the baffle and reducing the risk of secondary entrainment. In addition, the solid structure of the conical baffle or arc-shaped baffle cap can also block the straight short-circuit upward path of liquid vapor along the central region of the evaporation chamber 20, forcing all vapor to pass through the preset baffle gap 113, thereby ensuring that each stage of the baffle assembly 11 can effectively handle the entire vapor flow.

[0033] It should be noted that the specific value of the second preset spacing in this example should be determined comprehensively based on the inner diameter of the evaporation chamber 20, the flow rate of the liquid vapor, and the required airflow velocity of the preset baffle gap 113. If the second preset spacing is too small, the preset baffle gap 113 will become narrower, and the flow velocity of the liquid vapor will be too high. On the one hand, this will increase the pressure drop, and on the other hand, the high-speed airflow may shear and entrain the separated droplets again, resulting in secondary entrainment. If the second preset spacing is too large, the flow path of the liquid vapor in the turning area will become longer, the airflow velocity will decrease too quickly, and the inertial separation force obtained by the droplets will be insufficient, which will reduce the separation efficiency. In actual design, the second preset spacing can usually be set to 0.1 to 0.5 times the inner diameter of the annular guide plate. The specific value can be optimized and determined through fluid dynamics calculations or experimental tests. Both the conical baffle and the arc-shaped baffle cap are axisymmetric rotating structures with regular geometric shapes, which are convenient for processing, manufacturing, and installation. In actual production, either form can be selected for implementation according to processing conditions and cost requirements.

[0034] In some examples, such as Figure 2 and Figure 3As shown, the angle between the generatrix of the conical baffle and the horizontal plane is 30° to 60°, or the radius of curvature of the arc-shaped baffle cap is 0.3 to 0.8 times the inner diameter of the evaporation chamber 20. Thus, for the conical baffle, an angle within the above range allows the conical surface of the baffle to maintain a suitable inclination. When the angle is not less than 30°, the conical surface of the conical baffle has sufficient steepness to effectively block and deflect the rising airflow, ensuring that droplets obtain sufficient inertial separation force when impacting the conical surface. When the angle is not greater than 60°, the conical surface of the conical baffle is not too steep, preventing severe flow separation and local eddies of liquid vapor at the bottom of the conical baffle, thus maintaining the stability of the airflow. Simultaneously, the moderate slope of the conical surface allows captured droplets to slide smoothly down the conical surface without stagnation. For the arc-shaped baffle cap, when the radius of curvature of the arc surface is 0.3 to 0.8 times the inner diameter of the evaporation chamber 20, the curvature of the arc surface of the baffle cap can provide sufficient obstruction and guidance for the liquid vapor, allowing the airflow to smoothly change direction under the guidance of the arc surface of the baffle cap. At the same time, it avoids the problems of excessive local resistance due to an excessively small radius of curvature or insufficient separation effect due to an excessively large radius of curvature causing the baffle cap to become flat. Overall, the above-mentioned geometric parameters ensure that the baffle hood or baffle cap has both good hydrodynamic performance and droplet capture performance.

[0035] It should be noted that the specific values ​​of the generatrix angle and the radius of curvature of the arc surface in this example should be selected differently based on the physical properties of the material and the operating conditions. For example, when processing high-viscosity materials, the droplets slide slowly on the surface of the baffle, so a larger generatrix angle (e.g., 45°–60°) or a smaller radius of curvature of the arc surface (e.g., 0.3–0.5 times the inner diameter) can be used to make the conical or arc surface steeper, thereby enhancing the sliding effect of the droplets under gravity, shortening the residence time of the droplets on the wall, and reducing the risk of secondary entrainment. When processing low-viscosity materials, the droplet sliding resistance is small, so a smaller generatrix angle (e.g., 30°–45°) or a larger radius of curvature of the arc surface (e.g., 0.5–0.8 times the inner diameter) can be used to reduce the flow resistance when the airflow passes through, reduce pressure drop loss, and improve the energy efficiency of the system. In practical engineering, the above parameters can be adjusted according to the flow rate of liquid vapor. When the flow rate is high, a gentler angle or curvature can be used to reduce the pressure drop, while when the flow rate is low, a steeper angle or curvature can be used to enhance the separation effect.

[0036] In some examples, such as Figure 2 and Figure 3As shown, the bottom edge diameter of the conical baffle or arc-shaped baffle cap is larger than the inner edge diameter of the annular guide plate and smaller than the inner diameter of the evaporation chamber 20, so that the liquid vapor forms a reversible flow that diffuses from the center to the surrounding area when flowing through the preset baffle gap 113. Thus, since the bottom edge diameter of the conical baffle or arc-shaped baffle cap is larger than the inner edge diameter of the annular guide plate, the bottom edge of the conical baffle or arc-shaped baffle cap extends radially beyond the outer edge of the central channel 1111, so that the liquid vapor rising from the central channel 1111 cannot pass directly upward in a straight line, but must collide with the bottom surface of the conical baffle or arc-shaped baffle cap and then diffuse and change direction to the surrounding area, thereby forming a reversible flow pattern that diffuses from the central region of the evaporation chamber 20 to the circumferential wall. This diffusion-reversal process significantly increases the path length of droplets in the liquid vapor, prolonging their residence time within the separation region and giving them a greater chance to detach from the gas phase under inertial and gravitational forces. Furthermore, as the liquid vapor diffuses from the central channel 1111 outwards, the flow area gradually increases and the airflow velocity gradually decreases, which facilitates the settling of separated droplets and prevents secondary entrainment of droplets by the high-speed airflow. Simultaneously, the bottom diameter of the conical baffle or arc-shaped baffle cap is smaller than the inner diameter of the evaporation chamber 20, ensuring a sufficiently wide annular upward channel between the outer edge of the baffle or baffle cap and the inner wall of the evaporation chamber 20. This allows the redirected liquid vapor to smoothly flow upwards through this annular upward channel to the next stage baffle assembly 11 or the steam outlet 21, preventing blockage or dead zones in the baffle assembly 11 region.

[0037] It should be noted that the specific value of the bottom edge diameter of the conical baffle or arc-shaped baffle cap in this example should be determined comprehensively based on the inner edge diameter of the annular guide plate and the inner diameter of the evaporation chamber 20. The bottom edge diameter of the conical baffle or arc-shaped baffle cap can be set to 0.5 to 0.9 times the inner diameter of the evaporation chamber 20 to provide sufficient flow area for steam while ensuring effective baffle diffusion. When the ratio of the bottom edge diameter of the conical baffle or arc-shaped baffle cap to the inner diameter of the evaporation chamber 20 is less than 0.5, the annular rising channel between the outer edge of the conical baffle or arc-shaped baffle cap and the inner wall of the evaporation chamber 20 is too wide. The turning amplitude of the liquid vapor when passing through the bottom edge of the conical baffle or arc-shaped baffle cap is insufficient, and some vapor may rise directly in a straight line through the annular channel without sufficient turning, weakening the baffle separation effect. When the ratio is greater than 0.9, the annular rising channel is too narrow, the airflow velocity is too high, the pressure drop increases, and secondary entrainment is easily generated. Therefore, the above-mentioned dimensional relationships should be properly matched to ensure that the baffle assembly 11 operates under optimal conditions.

[0038] In some examples, such as Figure 2 and Figure 3As shown, the conical baffle or arc-shaped baffle cap is fixedly connected to the inner wall of the evaporation chamber 20 or to the upper surface of the annular guide plate via supporting ribs 114. The supporting ribs 114 are arranged at intervals along the circumference of the evaporation chamber 20, and the width direction of the supporting ribs 114 is parallel to the flow direction of the liquid vapor to reduce resistance to the vapor flow. In this way, the supporting ribs 114 can firmly position the conical baffle or arc-shaped baffle cap directly above the central channel 1111, ensuring that the coaxiality between the conical baffle or arc-shaped baffle cap and the annular guide plate and the second preset spacing remain unchanged during long-term operation, avoiding the displacement, tilting or loosening of the baffle due to steam impact or equipment vibration, and ensuring the stability and reliability of the separation effect. Meanwhile, the width direction of the support stiffener 114 is set parallel to the flow direction of the liquid vapor, so that the support stiffener 114 faces the airflow with its minimum windward area. This can minimize the obstruction effect of the stiffener on the flow of liquid vapor, reduce the possibility of local flow resistance and eddy current generation, and thus minimize the interference with the steam flow while ensuring the structural connection strength. This is conducive to maintaining the stability of the airflow and the continuity of the separation efficiency in the baffle assembly 11.

[0039] It should be noted that the number and thickness of the support ribs 114 in this example should be determined after structural strength verification based on the self-weight of the conical baffle or arc-shaped baffle cap and the impact force of the liquid vapor on the baffle. Typically, 4 to 8 support ribs 114 can be evenly arranged around the evaporation chamber 20 to ensure connection strength and balanced force distribution in all directions. The thickness of the support ribs 114 can be selected based on the size and weight of the baffle, generally ranging from 3mm to 10mm. Specifically, the width direction of the support ribs 114 should be parallel to the airflow direction as follows: the plane containing the surface of the support ribs 114 should be parallel to the axial direction of the evaporation chamber 20. That is, the width direction of the support ribs 114 extends radially along the evaporation chamber 20, and the thickness direction extends circumferentially along the evaporation chamber 20, thereby ensuring that the thickness side of the support ribs 114 faces the flow direction of the liquid vapor, minimizing the obstruction area to the airflow. The material of the supporting stiffener 114 should be the same as or have similar corrosion resistance and coefficient of thermal expansion as the conical baffle or arc-shaped baffle cap to avoid thermal stress or electrochemical corrosion problems caused by material differences. When the supporting stiffener 114 is fixedly connected to the upper surface of the annular guide plate, a connecting lug or welding base should be pre-installed at the corresponding position on the upper surface of the annular guide plate to ensure the strength and sealing of the connection.

[0040] In some examples, such as Figure 5As shown, the top of the conical baffle or arc-shaped baffle cap is also provided with a guide cone tip 1121 or a flow-dividing boss (not shown). The guide cone tip 1121 or flow-dividing boss is configured to initially divert the liquid-containing vapor rising to the central region of the second baffle 112, thereby reducing the direct impact load of the liquid-containing vapor on the top of the second baffle 112. Thus, when the liquid-containing vapor rises from the central channel 1111 of the annular guide plate and approaches the central region of the second baffle 112, the guide cone tip 1121 or flow-dividing boss first contacts the airflow. Its tip or raised curved surface can effectively divide and guide the airflow that was originally concentrated on the top center of the conical baffle or arc-shaped baffle cap, so that the liquid-containing vapor begins to undergo directional deflection and velocity redistribution before reaching the main wall of the conical baffle or arc-shaped baffle cap. This initial diversion significantly reduces the direct impact of liquid vapor on the top of the baffle, lowering the vibration and noise levels during operation. It also prevents fatigue damage in localized areas caused by prolonged exposure to high impact loads, thus extending the service life of the baffle. Furthermore, after pre-diversion by the guide cone tip 1121 or the diversion boss, the liquid vapor's flow direction is partially deflected before entering the pre-set baffle gap 113 between the conical baffle or arc-shaped baffle cap and the annular guide plate. This results in a more uniform airflow distribution, effectively adding a pre-separation stage before the actual diversion, which further enhances the overall separation efficiency of the baffle assembly 11.

[0041] It should be noted that the guide cone tip 1121 in this example can be specifically designed as a conical structure, with a cone angle typically ranging from 30° to 90°. Its bottom diameter is the same as the top diameter of the conical baffle or arc-shaped baffle cap, and its height can be designed according to the flow velocity of the liquid vapor, generally ranging from 10mm to 50mm. The flow-dividing boss in this example can be specifically designed as a hemispherical or ellipsoidal frustum structure, with a smooth transition surface to avoid dead zones or localized eddies around the boss. The guide cone tip 1121 or the flow-dividing boss can be integrally cast or stamped with the conical baffle or arc-shaped baffle cap, or it can be machined separately and fixed to the top center of the second baffle 112 by welding, riveting, or threaded connection. Its material should be the same as the main body material of the second baffle 112 to ensure consistent corrosion resistance in high-temperature and high-salt environments, while avoiding the risk of galvanic corrosion due to material differences at the connection interface. For applications involving high flow rates and high liquid content materials, the presence of the guide cone tip 1121 or the diversion boss is particularly necessary. However, for applications involving low flow rates and low liquid content materials, this structure can be omitted to simplify the manufacturing process.

[0042] In some examples, such as Figure 3 and Figure 4As shown, the number of baffle components 11 is three or four stages, and the first preset spacing between each stage of baffle components 11 increases progressively from bottom to top along the axial direction of the evaporation chamber 20 to adapt to the gradient changes in the flow velocity and liquid content of the liquid-containing vapor during its ascent. Thus, as the liquid-containing vapor rises, some droplets are separated and removed stage by stage, gradually reducing the liquid content in the gas phase. Simultaneously, the flow velocity distribution changes accordingly as the airflow passes through each stage of baffle components 11 due to variations in flow area and local resistance. The progressively increasing spacing between adjacent baffle components 11 from bottom to top allows for a relatively smaller buffer space between lower-level baffle components 11 (near the evaporation zone), suitable for handling rising steam with high liquid content and high flow velocity, enabling the steam to quickly enter the next-level baffle component 11 for enhanced separation within a shorter distance. Conversely, the relatively larger buffer space between upper-level baffle components 11 (near the steam outlet 21) is suitable for handling steam with significantly reduced liquid content and a more stable flow velocity, providing ample settling space and a velocity homogenization zone, which facilitates the full settling of residual fine droplets under gravity. This differentiated spacing ensures that the separation capacity of each baffle component 11 matches the state of the steam entering that stage, thereby improving the overall separation efficiency of the vapor-liquid separation structure 10 across the entire height range and preventing excessive load or overcapacity of a particular baffle component 11 due to improper spacing.

[0043] It should be noted that the specific value of the first preset spacing between each stage of the baffle assembly 11 in this example should be comprehensively designed based on the internal space height of the evaporation chamber 20, the number of stages of the baffle assembly 11, and the evaporation characteristics of the material. The increase in spacing between adjacent stages of the baffle assembly 11 can be proportional or set in a non-proportional manner according to actual operating conditions. For example, Figure 4 As shown, for the arrangement of the three-stage baffle assembly 11, the spacing between the first and second stages can be set to 0.3 to 0.5 times the inner diameter of the evaporation chamber 20, the spacing between the second and third stages can be set to 0.5 to 0.8 times the inner diameter of the evaporation chamber 20, and the spacing between the third stage and the steam outlet 21 can be further increased to 0.8 to 1.2 times the inner diameter of the evaporation chamber 20 to form a progressively expanding buffer space. In actual engineering design, the above spacing values ​​can also be verified and optimized through computational fluid dynamics simulation or cold model experiments to ensure that the best separation effect can be obtained under different operating conditions. The selection of three or four stages for the number of stages of the baffle assembly 11 is an optimal range determined after comprehensively considering the separation efficiency and equipment manufacturing cost. Too few stages will result in insufficient reversal paths and limited separation effect, while too many stages will complicate the structure and significantly increase the pressure drop.

[0044] In some examples, in adjacent baffle assemblies 11, the second baffle 112 of the upper baffle assembly 11 and the first baffle 111 of the lower baffle assembly 11 partially overlap axially in the evaporation chamber 20, so that the liquid vapor forms an S-shaped or Z-shaped deflection path between the adjacent baffle assemblies 11. Thus, by axially arranging the second baffle 112 for deflection in the upper baffle assembly 11 and the first baffle 111 for flow guidance in the lower baffle assembly 11 in a partially overlapping state, the liquid vapor, after exiting the upper baffle assembly 11, cannot directly rise in a straight line into the central channel 1111 of the lower baffle assembly 11. Instead, it must undergo lateral displacement in the horizontal direction, that is, re-converge from the circumferential wall region of the evaporation chamber 20 towards the central region, and then enter the flow path guided by the first baffle 111 of the lower baffle assembly 11. This spatial arrangement forces the liquid vapor to form an S-shaped or Z-shaped deflection trajectory between adjacent baffle assemblies 11, rather than a simple straight upward movement. The formation of this reversal path provides droplets with additional opportunities for inertial separation, so that residual droplets that were not separated in the previous stage baffle assembly 11 are again subjected to inertial force during the reversal process and are thrown towards the inner wall of the evaporation chamber 20 or the surface of the baffle, thereby further improving the stepwise removal efficiency of droplets. At the same time, it is also conducive to the redistribution and homogenization of airflow velocity during the reversal process.

[0045] It should be noted that in this example, the specific meaning of "the second baffle 112 of the upper-level baffle assembly 11 and the first baffle 111 of the lower-level baffle assembly 11 partially overlap in the axial direction" is that in the axial direction of the evaporation chamber 20, the bottom or lower region of the second baffle 112 of the upper-level baffle assembly 11 (such as a conical baffle or an arc-shaped baffle cap) and the top or upper region of the first baffle 111 of the lower-level baffle assembly 11 (such as an annular guide plate) are within the same height range, that is, their axial projections intersect. This overlapping arrangement ensures that the liquid-containing vapor flowing from the annular rising channel between the outer edge of the second baffle 112 of the upper-level baffle assembly 11 and the inner wall of the evaporation chamber 20 is constrained on the outside by the inner wall of the evaporation chamber 20 and on the inside by the outer wall of the upper-level baffle. Upon reaching the position of the first baffle 111 of the next-level baffle assembly 11, it must turn from the outside to the inside to enter the central channel 1111 of the first baffle 111, thus creating a natural deflection effect. In actual design, the axial overlap can be reasonably set according to the inner diameter of the evaporation chamber 20 and the expected deflection path length, generally set to 0.1 to 0.3 times the inner diameter of the evaporation chamber 20, to ensure that the deflection path is fully formed without excessively obstructing steam flow.

[0046] In some examples, such as Figures 2 to 5As shown, the surfaces of the first baffle 111 and / or the second baffle 112 are provided with a hydrophobic coating or a micro / nano-structured hydrophobic layer (not shown). This hydrophobic coating or micro / nano-structured hydrophobic layer is configured to reduce the adhesion of droplets to the baffle surface and promote rapid droplet aggregation and sliding. Thus, when droplets containing liquid vapor collide with the surface of the baffle provided with the hydrophobic coating or micro / nano-structured hydrophobic layer, the contact angle between the droplet and the wall surface is significantly increased due to the reduction of the surface energy of the solid surface by the hydrophobic coating or micro / nano-structured hydrophobic layer. This makes it difficult for the droplets to spread and adhere to the wall surface, instead maintaining a spherical shape and exhibiting high rollability. This surface characteristic allows droplets to roll off the wall more easily after impact under the influence of gravity or airflow drag, rather than forming a continuous liquid film. This effectively reduces the number and thickness of droplets remaining on the wall, lowering the risk of droplets being sheared and entrained again by subsequent high-speed steam. Furthermore, smaller droplets are more likely to collide and merge during the rolling process, forming larger droplets. These larger droplets have a faster settling velocity under gravity, allowing them to detach from the baffle surface more quickly and fall back into the evaporation zone. In addition, the hydrophobic surface also possesses anti-fouling and self-cleaning properties, which can delay the crystallization and deposition of salts on the baffle surface when handling high-salt materials, extending the equipment's maintenance cycle.

[0047] It should be noted that the hydrophobic coating in this example can be made of fluoropolymers such as polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), or fluorinated ethylene propylene copolymer (FEP), or silicone resin coatings. The coating thickness is typically 20 μm to 200 μm, and can be selected based on the size of the baffle and the expected wear resistance requirements. The micro / nano-structured hydrophobic layer in this example can be achieved by forming a rough surface with micron- and nano-scale composite structures on the baffle surface through chemical etching, anodizing, laser processing, or spraying nanoparticles, followed by modification with low surface energy materials to obtain superhydrophobic properties. In practical applications, since the baffle is exposed to high-temperature, high-salt steam environments for extended periods, the temperature resistance and corrosion resistance of the hydrophobic coating or micro / nano-structured hydrophobic layer are primary considerations when selecting it. For operating conditions with higher temperatures (e.g., exceeding 120°C), high-temperature resistant fluoropolymer coatings or micro / nano-structures treated for high-temperature stability should be preferred. This surface treatment method can be selectively used based on material characteristics and operating temperature, and is not mandatory in all operating conditions.

[0048] In some examples, such as Figures 2 to 5As shown, the first baffle 111 and / or the second baffle 112 are made of corrosion-resistant metal materials or high-temperature resistant engineering plastics. Thus, when treating high-salt wastewater or chemical materials, the liquid vapor in the evaporation chamber 20 typically contains corrosive media such as chlorides and sulfates, and the operating temperature can reach above 100°C or even higher. Ordinary carbon steel materials may suffer severe corrosion in a short period, affecting not only the structural strength and service life of the baffles, but also potentially contaminating materials or condensate with corrosion products. Using corrosion-resistant metal materials (such as duplex stainless steel, titanium, nickel-based alloys, etc.) or high-temperature resistant engineering plastics (such as polyetheretherketone, polyimide, etc.) to make the first baffle 111 and / or the second baffle 112 ensures that the baffles maintain structural integrity and dimensional stability in harsh high-temperature and high-salt environments over a long period, reducing the risk of corrosion thinning, stress corrosion cracking, or material aging failure. This guarantees the reliable operation of the vapor-liquid separation structure 10 throughout its entire lifespan, reduces equipment downtime and maintenance due to baffle corrosion damage, and improves the operating efficiency and economic benefits of the evaporation system.

[0049] It should be noted that the corrosion-resistant metal materials used in this example can specifically be duplex stainless steel (such as 2205, 2507), titanium (such as TA2, TC4), or nickel-based alloys (such as C-276, Inconel 625). These materials exhibit excellent resistance to pitting and stress corrosion in high-temperature steam environments containing chloride ions. For conditions with relatively weak corrosion or lower operating temperatures, economical stainless steel (such as 316L, 317L) can also be used as an alternative to reduce equipment manufacturing costs. The high-temperature resistant engineering plastics used in this example, such as polyetheretherketone (PEEK), have advantages such as a long-term operating temperature up to 250℃, resistance to acid and alkali corrosion, low density, and light weight. They are suitable for applications where equipment weight is a concern or where metal ion contamination needs to be avoided. However, their strength and stiffness are lower than those of metallic materials; therefore, the wall thickness should be appropriately increased or reinforcing ribs added during structural design to ensure sufficient load-bearing capacity. The selection of materials should comprehensively consider factors such as the corrosiveness of the medium, operating temperature, equipment design life, and economic costs, and should be rationally matched by designers based on specific operating conditions.

[0050] In some examples, a liquid collection trough (not shown) is provided on the lower side of the first baffle 111 or the outer edge of the second baffle 112. The liquid collection trough extends circumferentially along the evaporation chamber 20 and is configured to collect the droplets separated by the baffle. The liquid formed by the collected droplets is then guided back to the liquid pool at the bottom of the evaporation chamber 20 through a liquid guide pipe. Thus, during the baffle separation process, droplets captured by the surface of the baffle and sliding down the wall form a converging liquid flow when they reach the lower side or outer edge of the baffle. Without the collection and guidance of the liquid collection trough, these liquid flows might be dispersed by the rising steam flow and re-entrained, or large, irregularly falling droplets might form at the edge of the baffle, causing localized droplet splashing. The liquid collection trough effectively collects these circumferentially distributed liquid flows and guides them to the liquid pool at the bottom of the evaporation chamber 20 through the liquid guide pipe, allowing the separated liquid to return to the evaporation zone in an orderly manner. This avoids secondary dispersion and entrainment of the liquid in the baffle area, further improving separation efficiency. Meanwhile, the drainage effect of the liquid collection tank and the liquid guide pipe can keep the surface of the baffle relatively dry, reduce the coverage area of ​​the liquid film on the surface of the baffle, and help maintain the separation performance of the baffle for subsequent liquid vapor.

[0051] It should be noted that the liquid collection tank in this example can specifically adopt an annular tank structure, with a cross-sectional shape that can be V-shaped, U-shaped, or rectangular. The opening of the tank is positioned upwards below the first baffle 111 or below the outer edge of the second baffle 112 to collect droplets sliding down from the surface of the baffle. The width and depth of the liquid collection tank should be designed according to the expected liquid flow rate. Generally, the tank width can be 20mm to 60mm, and the tank depth can be 15mm to 40mm. Two to eight liquid guide pipes can be installed circumferentially, evenly distributed at the bottom of the annular liquid collection tank. The inner diameter of the liquid guide pipes should be determined according to the liquid flow rate, typically 10mm to 25mm. The liquid guide pipes should extend downwards below the liquid surface of the evaporation chamber 20 to prevent steam from entering the liquid collection tank through the liquid guide pipes. The liquid collection tank can be made of the same material as the baffle and fixed to the baffle or the inner wall of the evaporation chamber 20 by welding, riveting, or bolting. For applications involving materials that are prone to crystallization, heat tracing devices or insulation layers can be installed in the collection tank and the guide pipe to prevent crystals from clogging the tank or pipe.

[0052] In some examples, such as Figure 5As shown, the vapor-liquid separation structure 10 also includes a demister element 13 disposed between the uppermost baffle assembly 11 and the steam outlet 21. The demister element 13 is at least one of a wire mesh demister, a cyclone demister, and a blade separator. The demister element 13 is configured to perform final liquid phase capture on the liquid-containing vapor after multi-stage baffle separation. In this way, after the liquid-containing vapor undergoes repeated back-and-forth separation by the multi-stage baffle assembly 11, most of the entrained droplets have been removed. However, the gas phase may still contain a small number of droplets with extremely small particle sizes (such as less than 10 μm). These tiny droplets are difficult to separate effectively in the baffle assembly 11 by inertial impaction due to their small mass and weak inertial force. A demister element 13 is added downstream of the baffle assembly 11. This element utilizes mechanisms such as wire mesh interception and coalescence, centrifugal separation by cyclones, or multiple collection by blade separators to precisely capture the liquid-containing steam after multi-stage baffle separation. This further removes residual fine droplets, significantly reducing the total amount of liquid entrainment at the steam outlet 21 and improving steam quality. Especially in applications requiring high steam purity (such as condensate recovery or processes sensitive to steam quality), the demister element 13 provides ultimate quality assurance.

[0053] It should be noted that the demister element 13 in this example can be selected from different types depending on the specific separation accuracy requirements and allowable pressure drop loss. Wire mesh demisters have the advantages of simple structure and high demisting efficiency (removal rate of droplets larger than 5μm can reach over 98%), but they are prone to clogging and have limited separation effect on droplets smaller than 3μm. Cyclone demisters separate droplets through centrifugal force, handling large gas volumes with low pressure drop, making them suitable for high-load conditions. Feather separators employ a specially designed feather structure, achieving efficient separation through multiple directional changes and droplet coalescence, maintaining high collection efficiency even for droplets as small as 1μm. In practical applications, various demister elements 13 can also be used in combination, for example, first passing the liquid through a cyclone demister for coarse separation, and then through a wire mesh demister for fine separation, to obtain the best separation effect and operational reliability. The installation position of the demisting element 13 should ensure that there is sufficient distance between it and the uppermost baffle assembly 11 to prevent the high-speed airflow at the outlet of the baffle assembly 11 from directly impacting the demisting element 13, causing local overload or damage to the demisting element 13.

[0054] In some examples, such as Figure 5As shown, the vapor-liquid separation structure 10 also includes a flow equalization distribution plate 14. The flow equalization distribution plate 14 is located upstream of the baffle assembly 11 closest to the bottom of the evaporation chamber 20. The flow equalization distribution plate 14 is a perforated plate structure or a grid structure, and is configured to pre-uniformly distribute the rising liquid-containing vapor from the bottom of the evaporation chamber 20 and intercept some large-diameter droplets. Thus, in the forced circulation evaporator 1, due to the possibility of localized violent boiling or the impact of circulating liquid backflow on the boiling liquid surface, the velocity and liquid content of the rising steam before entering the first-stage baffle assembly 11 are often unevenly distributed across the cross-section of the evaporation chamber 20. Some areas have high steam velocity and high liquid content, while other areas have low velocity and low liquid content. If this uneven airflow directly enters the baffle assembly 11, it will cause some areas of the baffle assembly 11 to be overloaded and the separation effect to decrease, while other areas will not be fully utilized. The flow equalization distribution plate 14 utilizes the flow resistance generated by the orifice plate or grid on the rising steam to redistribute the steam's velocity and direction as it passes through the distribution plate, thus achieving a more uniform flow state before entering the baffle assembly 11. Simultaneously, the openings or grid gaps in the flow equalization distribution plate 14 can intercept and pre-separate large-diameter droplets in the rising steam. Some larger droplets are captured and fall back to the liquid surface upon impact with the plate surface or grid bars of the flow equalization distribution plate 14, thereby reducing the separation load on the subsequent baffle assembly 11 and improving the overall processing capacity and separation efficiency of the vapor-liquid separation structure 10.

[0055] It should be noted that the opening ratio or grid gap of the flow equalization distribution plate 14 in this example should be designed according to the expected steam flow rate and allowable pressure drop. The opening ratio can generally be controlled within the range of 30% to 60%, and the opening diameter or grid gap can be 5mm to 20mm. The flow equalization distribution plate 14 can be in the form of a flat perforated plate, or a conical or arc-shaped distribution plate, to further guide the airflow towards the center or circumferential area of ​​the evaporation chamber 20. The material of the flow equalization distribution plate 14 should be the same as that of the baffle assembly 11 or have equivalent corrosion resistance to ensure reliability for long-term use in high-temperature and high-salt environments. The axial distance between the flow equalization distribution plate 14 and the first-stage baffle assembly 11 should be large enough to avoid the flow equalization distribution plate 14 interfering too closely with the flow field entering the baffle assembly 11. It can generally be set to 0.2 to 0.5 times the inner diameter of the evaporation chamber 20. In practical engineering, when the cross-sectional area of ​​the evaporation chamber 20 is small or the steam rising speed is relatively uniform, the flow distribution plate 14 may be omitted as needed to simplify the structure and reduce costs.

[0056] In one embodiment, such as Figure 1As shown in the illustration, this application also provides a forced circulation evaporator 1, which includes an evaporation chamber 20, a heating chamber 30, a circulation pump 40, and the vapor-liquid separation structure 10 described in the above embodiment. The evaporation chamber 20 has a steam outlet 21 at its top. The vapor-liquid separation structure 10 is located in the top region of the evaporation chamber 20, above the boiling liquid surface and below the steam outlet 21. The heating chamber 30 is connected to the evaporation chamber 20 via a circulation pipe 50, and the circulation pump 40 is mounted on the circulation pipe 50.

[0057] It should be noted that the forced circulation evaporator 1 of this application embodiment is mainly used in the manufacture of special environmental protection equipment for water pollution, solid waste pollution, air pollution, heavy metal pollution, and nuclear pollution prevention and control, as well as in scenarios such as zero-discharge treatment of high-salt wastewater, evaporation and concentration of chemical materials, volume reduction treatment of pharmaceutical wastewater, and high-multiplication concentration of complex water quality such as oilfield produced water and coal chemical wastewater. In these application scenarios, the materials to be treated usually have characteristics such as high salt content, complex composition, easy foaming, and easy scaling, which puts high demands on the separation performance and operational stability of the evaporation system. The forced circulation evaporator 1 of this embodiment, by configuring the above-mentioned multi-stage baffled vapor-liquid separation structure 10 in its evaporation chamber 20, can effectively solve the problem of severe liquid entrainment at the steam outlet 21 under high load conditions without increasing external power consumption, reduce the pollution risk of downstream condensate and secondary steam pipelines, and ensure the stability and reliability of the evaporation system in long-term continuous operation. The bottom of the evaporation chamber 20 is typically equipped with a liquid pool to accommodate circulating materials and separated, falling liquid. The liquid level is controlled by balancing the feed and discharge rates. The vapor-liquid separation structure 10 should always be positioned above the highest liquid level to prevent the liquid from directly submerging the baffle assembly 11 and affecting the separation effect. The circulating pump 40 is the core power equipment of the forced circulation evaporator 1. Its head and flow rate should be rationally selected based on the material circulation volume, the resistance of the heating chamber 30, and the operating pressure of the evaporation chamber 20 to ensure that the flow velocity of the material in the heating tube is sufficient to suppress scaling and maintain a good heat transfer coefficient. In addition, the heating medium of the heating chamber 30 can be selected from steam, thermal oil, or hot water, depending on the material characteristics and heat source conditions. The structure of the heating chamber 30 can be conventional, such as tubular, plate, or spiral, to meet the heat transfer requirements under different operating conditions.

[0058] In this way, the forced circulation evaporator 1 of this application embodiment, through the above-described structural configuration, integrates a multi-stage baffled vapor-liquid separation structure 10 within its evaporation chamber 20. This vapor-liquid separation structure 10 can efficiently separate rising liquid-containing vapor within a wide range of operating conditions, significantly reducing the amount of liquid entrainment at the steam outlet 21, thereby ensuring the quality of the produced steam, reducing scaling and corrosion problems in downstream equipment caused by salt carryover, extending equipment operating cycles, and reducing maintenance costs. At the same time, this vapor-liquid separation structure 10 does not require additional power drive, has good economic efficiency and applicability, and can meet the long-term stable operation requirements under harsh conditions such as high salt and high load.

[0059] In some examples, such as Figure 1 As shown, the forced circulation evaporator 1 is used for evaporating and crystallizing high-salt wastewater or concentrating high-concentration organic waste liquid. Thus, evaporating and crystallizing high-salt wastewater and concentrating organic waste liquid are the most typical application areas for the forced circulation evaporator 1. In these devices, the steam within the evaporation chamber 20 generally has high liquid content, high corrosiveness, and is prone to foaming, placing particularly stringent requirements on the vapor-liquid separation structure 10. When applied to such devices, the forced circulation evaporator 1 of this embodiment fully utilizes the inertial separation advantage of the multi-stage baffled path, maintaining high separation efficiency even when processing high-liquid-content steam. This effectively reduces the entrainment of salt or organic matter in the secondary steam, ensuring the quality requirements for condensate reuse or compliant discharge. Simultaneously, it reduces the tendency for scaling on the inner wall of the evaporation chamber 20 and the steam outlet 21 pipeline, extending the cleaning cycle and service life of the equipment, demonstrating significant application advantages.

[0060] It should be noted that the high-salt wastewater evaporation and crystallization equipment in this example typically treats wastewater with a total dissolved solids (TDS) content of 5% to 30% or even higher. During the evaporation and crystallization process, salt precipitation can easily lead to salt mist entrainment in the steam. The vapor-liquid separation structure 10 in this example, through multi-stage baffles and hydrophobic surface treatment, can effectively reduce the amount of salt mist entrainment, protecting the subsequent condenser and piping system. The high-concentration organic wastewater concentration equipment in this example treats materials that typically contain surfactants or easily foaming components, which easily generate a large amount of foam during evaporation. The flow distribution plate 14 and baffle assembly 11 in this example can effectively break up and intercept the foam, preventing it from entering the steam outlet 21. The operating pressure of this equipment can be negative pressure evaporation (e.g., -0.08MPa to -0.02MPa) or atmospheric pressure evaporation. The operating temperature varies accordingly based on the boiling point of the material, generally between 50℃ and 120℃. Specific parameters should be designed according to the properties of the material and process requirements.

[0061] In some examples, such as Figure 1As shown, the operating pressure of the evaporation chamber 20 is -0.1 MPa to 1.0 MPa, the operating temperature is 60℃ to 150℃, and the rising velocity of the liquid vapor is 0.5 m / s to 5 m / s. Thus, the above operating parameter range covers the operating conditions of most actual working conditions of the industrial forced circulation evaporator 1. Specifically, the wide pressure range from negative to positive pressure adapts to different process requirements from vacuum evaporation to pressurized evaporation; the wide temperature range of 60℃ to 150℃ covers the typical operating range from low-temperature evaporation of heat-sensitive materials to high-temperature concentration of high-boiling-point materials; and the rising vapor velocity of 0.5 m / s to 5 m / s covers the airflow velocity changes under different throughputs from low to high loads. Within the above parameter range, the vapor-liquid separation structure 10 can provide effective vapor-liquid separation through the multi-stage reversal path of the baffle assembly 11, indicating that the vapor-liquid separation structure 10 implemented in this application has good adaptability to operating conditions and operational flexibility, and can be widely applied in forced circulation evaporators 1 of different scales, materials, and process conditions.

[0062] It should be noted that the operating pressure, temperature, and steam upward velocity in this example are interrelated operating parameters. In specific designs, these parameters should be determined comprehensively based on factors such as the thermal properties of the material, the evaporation rate, the cross-sectional area of ​​the evaporation chamber 20, and the heating capacity of the heating chamber 30. The steam upward velocity is a key parameter affecting the design of the vapor-liquid separation structure 10. When the velocity is 0.5 m / s to 2 m / s, it is considered a low-load condition, and the spacing between the baffle components 11 can be appropriately increased to fully utilize the gravity settling effect. When the velocity is 2 m / s to 5 m / s, it is considered a high-load condition, and the spacing between the baffle components 11 needs to be appropriately reduced to enhance the inertial separation effect. Simultaneously, the hydrophobic treatment of the baffle surface should be strengthened to prevent secondary entrainment. In actual engineering, the specific values ​​of the above parameters should be optimized and determined through process calculations and fluid dynamics simulations, and verified and adjusted based on actual operating data after the equipment is put into operation.

[0063] In summary, the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A vapor-liquid separation structure for a forced circulation evaporator, wherein the forced circulation evaporator is provided with an evaporation chamber and a steam outlet, characterized in that, The vapor-liquid separation structure includes at least two stages of baffle assemblies. These at least two stages of baffle assemblies are sequentially arranged along the axial direction of the evaporation chamber between the evaporation chamber and the steam outlet. Any two adjacent stages of baffle assemblies maintain a first preset distance along the axial direction of the evaporation chamber to form a corresponding steam buffer space. Each baffle assembly includes a first baffle element and a second baffle element. The first baffle is fixed in the evaporation chamber and is configured to guide the liquid vapor to form a radial or circumferential flow; The second baffle is fixed in the evaporation chamber and located downstream of the first baffle. It is configured to guide the liquid-containing vapor to the next stage baffle assembly or the steam outlet according to a preset path, and to change the flow direction of the liquid-containing vapor so that the liquid-containing vapor forms a reversal path between two adjacent stages of the baffle assembly.

2. The vapor-liquid separation structure according to claim 1, characterized in that, The first baffle is an annular guide plate, which is continuously arranged along the circumference of the evaporation chamber. The inner edge of the annular guide plate forms a central channel for the liquid vapor to pass through. The outer edge of the annular guide plate is sealed and fixed to the inner wall of the evaporation chamber. The plate surface of the annular guide plate is inclined or horizontal relative to the axial direction of the evaporation chamber, so as to guide the rising liquid vapor in a radial flow or circumferential swirling manner to the central channel or the inner wall of the evaporation chamber.

3. The vapor-liquid separation structure according to claim 2, characterized in that, The surface of the annular guide plate gradually slopes upwards from the inner wall of the evaporation chamber towards the center, with an inclination angle of 5° to 45°; and / or, The inner edge of the annular guide plate is provided with a guide flange or serrated structure for breaking up large-diameter liquid droplets in the liquid vapor.

4. The vapor-liquid separation structure according to claim 2, characterized in that, The second baffle is a conical baffle or an arc-shaped baffle cap. The conical baffle or the arc-shaped baffle cap is disposed directly above the central channel, and the conical baffle or the arc-shaped baffle cap maintains a second preset distance from the corresponding annular guide plate in the axial direction of the evaporation chamber, so as to form a preset baffle gap between the annular guide plate and the conical baffle or the arc-shaped baffle cap for the liquid vapor to turn and pass through.

5. The vapor-liquid separation structure according to claim 4, characterized in that, The angle between the generatrix of the conical baffle and the horizontal plane is 30° to 60°, or the radius of curvature of the arc-shaped baffle is 0.3 to 0.8 times the inner diameter of the evaporator chamber; and / or, The bottom edge diameter of the conical baffle or the arc-shaped baffle cap is larger than the inner edge diameter of the annular guide plate and smaller than the inner diameter of the evaporation chamber, so that the liquid vapor forms a reversible flow that diffuses from the center to the surrounding area when flowing through the preset baffle gap; and / or, The conical baffle or the arc-shaped baffle cap is fixedly connected to the inner wall of the evaporation chamber or to the upper surface of the annular guide plate by supporting ribs. The supporting ribs are arranged at intervals along the circumference of the evaporation chamber, and the width direction of the supporting ribs is parallel to the flow direction of the liquid-containing vapor to reduce resistance to the vapor flow; and / or, The top of the conical baffle or the arc-shaped baffle cap is also provided with a guide cone tip or a diversion boss. The guide cone tip or the diversion boss is configured to perform initial diversion of the liquid vapor rising to the central region of the second baffle, so as to reduce the direct impact load of the liquid vapor on the top of the second baffle.

6. The vapor-liquid separation structure according to claim 1, characterized in that, The number of the baffle components is three or four, and the first preset spacing between each baffle component increases gradually from bottom to top along the axial direction of the evaporation chamber to adapt to the gradient changes in the flow rate and liquid content of the liquid-containing vapor during its ascent.

7. The vapor-liquid separation structure according to claim 1, characterized in that, In two adjacent stages of the baffle assembly, the second baffle of the upper stage baffle assembly and the first baffle of the lower stage baffle assembly partially overlap in the axial direction of the evaporation chamber, so that the liquid vapor forms an S-shaped or Z-shaped return path between the two adjacent stages of the baffle assembly.

8. The vapor-liquid separation structure according to claim 1, characterized in that, The surface of the first baffle and / or the surface of the second baffle are provided with a hydrophobic coating or a micro / nano-structured hydrophobic layer, wherein the hydrophobic coating or the micro / nano-structured hydrophobic layer is configured to reduce the adhesion of droplets on the surface of the baffle and promote the rapid sliding off of droplets after aggregation; and / or, The first baffle and / or the second baffle are made of corrosion-resistant metal materials or high-temperature resistant engineering plastics; and / or, A liquid collection tank is provided on the lower side of the first baffle or the outer edge of the second baffle. The liquid collection tank extends circumferentially along the evaporation chamber and is configured to collect the droplets separated by the baffle. The liquid formed by collecting the droplets is then guided back to the liquid pool at the bottom of the evaporation chamber through a liquid guide pipe. And / or, The vapor-liquid separation structure further includes a demister element disposed between the uppermost baffle assembly and the steam outlet. The demister element is at least one of a wire mesh demister, a cyclone demister, and a blade separator. The demister element is configured to perform final liquid-phase capture of the liquid-containing vapor after multi-stage baffle separation; and / or The vapor-liquid separation structure further includes a flow equalization distribution plate, which is located upstream of the baffle assembly closest to the bottom of the evaporation chamber. The flow equalization distribution plate is a perforated plate structure or a grid structure, and is configured to pre-uniformly distribute the liquid-containing vapor rising from the bottom of the evaporation chamber and intercept some large-diameter droplets.

9. A forced circulation evaporator, characterized in that, The forced circulation evaporator includes an evaporation chamber, a heating chamber, a circulation pump, and a vapor-liquid separation structure as described in any one of claims 1 to 8. The top of the evaporation chamber has a steam outlet, and the vapor-liquid separation structure is located in the top region of the evaporation chamber, above the boiling liquid surface of the evaporation chamber and below the steam outlet. The heating chamber is connected to the evaporation chamber through a circulation pipe, and the circulation pump is located on the circulation pipe.

10. The forced circulation evaporator according to claim 9, characterized in that, The forced circulation evaporator is a high-salt wastewater evaporation and crystallization device or a high-concentration organic waste liquid concentration device; and / or The operating pressure of the evaporation chamber is -0.1MPa to 1.0MPa, the operating temperature of the evaporation chamber is 60℃ to 150℃, and the upward flow velocity of the liquid vapor is 0.5m / s to 5m / s.

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