A multi-stage conical vortex flash evaporator

Abstract

This invention provides a multi-stage conical vortex flash evaporator, comprising a vertical tank body with a steam discharge section at the top and a liquid discharge section at the bottom; several layers of conical sleeves vertically arranged inside the tank body, with each layer of conical sleeves spaced apart from the inside out, and adjacent layers of conical sleeves and the interior of the innermost conical sleeve forming a vertically connected flash evaporation channel, the radial cross-section of which is circular or annular. This multi-stage conical vortex flash evaporator, by arranging multiple layers of conical sleeves inside the vertical tank body, and providing a heatable sintered flash evaporation layer on the working surface of each layer of conical sleeves, allows for efficient gas-liquid separation through a liquid distributor on the tube body during operation. The sintered flash evaporation layer within the flash evaporation channel provides a large number of vaporization nuclei to promote flash evaporation, and the resulting vapor-liquid mixture undergoes multi-stage vortex motion within each flash evaporation channel, utilizing centrifugal force.

Description

Technical Field

[0001] This invention relates to the field of low-temperature waste heat recovery technology, and in particular to a multi-stage conical vortex flash evaporator. Background Technology

[0002] In the field of industrial energy conservation, flash evaporation to generate low-pressure steam from a low-temperature heat source (such as hot water at 70-150℃), followed by pressurization by a steam compressor for reuse, is an important waste heat recovery technology. The core equipment of this technology is the flash tank, whose performance directly determines the efficiency of energy recovery.

[0003] Current flash evaporators typically employ a simple container structure, where hot water enters through nozzles or a water distribution plate and flashes naturally under low pressure. This approach presents an inherent contradiction: on the one hand, to enhance vaporization, the hot water needs to be dispersed into fine droplets to increase the vaporization surface area; on the other hand, excessively fine droplets are easily entrained by the generated steam flow, leading to difficulties in gas-liquid separation. This not only reduces steam quality but may also cause cavitation in subsequent pipelines and compression equipment.

[0004] Existing technologies attempt to improve separation by adding a single cyclone plate or demister inside the flash tank, but this often treats "vaporization" and "separation" as two independent processes, failing to achieve synergistic optimization from the root, resulting in bulky equipment with limited efficiency.

[0005] Therefore, in order to solve the above problems, the present invention proposes a multi-stage conical vortex flash evaporator that can deeply couple efficient vaporization and efficient separation processes. Summary of the Invention

[0006] To address the problems existing in the prior art, the present invention provides a multi-stage conical vortex flash evaporator.

[0007] According to one objective of the present invention, a multi-stage conical vortex flash evaporator is provided, comprising a vertical tank body, wherein the tank body is provided with a steam discharge section located at the upper part and a liquid phase discharge section located at the lower part;

[0008] Several layers of conical sleeves are vertically arranged inside the tank body. Each layer of conical sleeves is arranged sequentially from the inside to the outside. The conical sleeves of adjacent layers and the inside of the innermost conical sleeve form a flash evaporation channel that is connected vertically. The radial section of the flash evaporation channel is circular or annular, and its diameter gradually decreases from top to bottom. A heatable sintered flash evaporation layer is provided on the side of the conical sleeve facing the flash evaporation channel.

[0009] A liquid distributor is provided with a plurality of output terminals corresponding to the upper part of each of the flash channels, and the output direction of the output terminals is set along the tangential direction of the flash channels.

[0010] Preferably, the flash channels, from the inside out, have their lower openings arranged at intervals from top to bottom.

[0011] Preferably, the conical sleeve is provided with at least 3 layers, and the conical sleeves of adjacent layers form several layers of annular flash channels, the diameter of each annular flash channel gradually increasing from the inside to the outside.

[0012] Preferably, the vertical tank is cylindrical; a steam outlet is provided at the center of the top of the tank, which forms the steam discharge section; a liquid discharge pipe is provided at the bottom of the tank, which forms the liquid discharge section;

[0013] The conical sleeves and the tank body of each layer are coaxially arranged.

[0014] Preferably, the shape of the conical sleeve matches the shape of the flash evaporation channel, and the conical sleeve is provided with a conical part, and the cone angle of the conical part in each layer of the conical sleeve is in the same upward direction.

[0015] Preferably, the conical sleeve includes a vertical part and a conical part connected sequentially from top to bottom, wherein the vertical part is a cylinder and the conical part is a truncated cone with an upward cone angle, the connection positions of the vertical part and the conical part are flush, and the connection points of the vertical part and the conical part of each layer of the conical sleeve are flush;

[0016] The output end of the liquid distributor is positioned corresponding to the vertical section.

[0017] Preferably, the upper ends of each of the conical sleeves are flush with each other, and the upper ends of the conical sleeves are connected to the inner wall of the tank body by support ribs. The support ribs are arranged radially along the conical sleeves, and there are multiple support ribs arranged at intervals along the circumference of the conical sleeves.

[0018] Preferably, the inner and outer walls of each conical sleeve are covered with a porous sintered flash layer by plasma spraying.

[0019] Preferably, a liquid inlet is provided on the middle wall of the tank, and a liquid distributor is connected to the liquid inlet. The output end of the liquid distributor is suspended inside a multi-layer conical sleeve, and the liquid tangential distributor has a tubular structure.

[0020] The liquid distributor has tangential slots of different sizes on the lower part of its pipe wall.

[0021] Preferably, the upper part of the tank is provided with a wire mesh demister, which is located between the steam outlet and the conical sleeve.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] This multi-stage conical cyclone flash tank integrates a sintered flash layer with high-efficiency vaporization and a multi-layer flash channel with cyclone separation, so that the vaporization process of hot water occurs on the separation surface, while the separation process continuously creates new vaporization surfaces. The synergy between vaporization and separation depths achieves spatiotemporal coupling and mutual promotion of the two processes, fundamentally solving the problem of low recovery efficiency caused by setting vaporization and separation as two independent links in existing technologies.

[0024] Among them, the sintered flash evaporation layer provides a stable and massive amount of vaporization cores, ensuring an extremely high initial vaporization rate; the multi-layer swirling liquid film in the flash evaporation channel has a large area, a thin liquid layer, a short bubble diffusion path, and strong centrifugal force, which effectively prevents droplet entrainment and ensures the high dryness of the outlet steam.

[0025] Within the limited tank space, radially stacked conical sleeves are installed, which increases the effective vaporization surface area and separation path length, making the flash tank small in size, highly efficient, and with a large processing capacity.

[0026] This multi-stage conical vortex flash tank has no moving parts inside, a robust conical sleeve structure, and a sintered metal layer that is corrosion-resistant, high-temperature resistant, and has a long overall service life. It can adapt to fluctuations in operating conditions, ensuring the stable and reliable operation of the flash tank.

[0027] The present invention will be further described below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0028] Figure 1 This is a schematic cross-sectional view of a multi-stage conical vortex flash evaporator according to the present invention;

[0029] Figure 2 for Figure 1 A top view of the AA section;

[0030] Figure 3 This is a cross-sectional schematic diagram of a liquid distributor in a multi-stage conical vortex flash tank according to the present invention;

[0031] Figure 4 This is a schematic diagram showing the distribution of the liquid distributor between the various sleeves in a multi-stage conical vortex flash tank according to the present invention;

[0032] Figure 5 This is a three-dimensional schematic diagram of the slit groove on the liquid distributor in a multi-stage conical vortex flash tank according to the present invention. Detailed Implementation

[0033] The following description is intended to provide a detailed account of the invention so that those skilled in the art can implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art. The basic principles of the invention defined in the following description can be applied to other embodiments, modifications, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the invention.

[0034] Please see Figure 1-3 The present invention provides a technical solution: a multi-stage conical vortex flash tank, the core innovation of which is that the tank body 1 is provided with multiple conical sleeves 2 inside, and flash channels with gradually increasing diameter from the inside to the outside are formed between the conical sleeves 2; the working surface of the conical sleeves 2, that is, the inner and outer wall surfaces in contact with the fluid, are provided with sintered flash layers 3; a liquid distributor 5 is provided on the tank body 1, which extends into each flash channel and whose output direction is tangent to the flash channel.

[0035] Specifically, the multi-stage conical vortex flash evaporator includes:

[0036] A vertical tank 1, wherein the tank 1 is provided with a steam discharge section located at the top and a liquid discharge section located at the bottom;

[0037] Several layers of conical sleeves 2 are vertically arranged inside the tank body 1. Each layer of conical sleeves 2 is arranged sequentially from the inside to the outside. The conical sleeves 2 of adjacent layers and the innermost conical sleeve 2 form a flash evaporation channel that is connected vertically. The radial section of the flash evaporation channel is circular or annular, and its diameter gradually decreases from top to bottom. The radial section of the flash evaporation channel formed between adjacent conical sleeves 2 is annular, and the radial section of the flash evaporation channel inside the innermost conical sleeve 2 is circular. The side of the conical sleeve 2 facing the flash evaporation channel, that is, the working surface of the conical sleeve 2, is provided with a heatable sintered flash evaporation layer 3.

[0038] Liquid distributor 5, which is provided with a plurality of output terminals corresponding to the upper part of each of the flash channels, and the output direction of the output terminals is set along the tangential direction of the flash channels.

[0039] By setting multiple conical sleeves 2 inside the vertical tank 1, and setting a heatable sintered flash layer 3 on the working surface of the multiple conical sleeves 2, when in use, the liquid distributor 5 on the pipe body introduces hot water tangentially to the surface of each flash channel through the output end. The sintered flash layer 3 in the flash channel provides a huge amount of gasification core to promote flashing. The generated gas-liquid mixture undergoes multi-stage swirling motion in each flash channel, and gas-liquid separation is achieved efficiently by using centrifugal force.

[0040] This multi-stage conical vortex flash evaporator deeply couples efficient vaporization and efficient separation processes, resolving the contradiction between "enhanced vaporization" and "preventing entrainment" in traditional flash evaporators. It has the advantages of compact structure, high efficiency, and good steam quality.

[0041] Further, see Figure 1 The flash evaporation channels, arranged from the inside out, have their lower openings spaced out from top to bottom. This arrangement allows the liquid separated from the inner and outer flash evaporation channels to collect orderly and in stages at the bottom of the tank, effectively preventing the fluids from different channels from impacting, mixing, and entraining each other at the bottom of the tank. This reduces the risk of secondary entrainment, ensures final gas-liquid separation, and makes the liquid phase discharge more stable. During use, the gas-liquid mixture in the flash evaporation channels can spiral downwards and outwards under inertia, passing through the flash evaporation channels between the conical sleeves 2 step by step. During this process, the liquid film is thrown towards the wall by centrifugal force, and bubbles diffuse to the surface, achieving liquid-vapor separation.

[0042] See Figure 1 The vertical tank 1 is cylindrical; a steam outlet 6 is provided at the center of the top of the tank 1, which forms a steam discharge section; a liquid discharge pipe 7 is provided at the bottom of the tank 1, which forms a liquid discharge section.

[0043] The conical sleeves 2 and the tank body 1 in each layer are coaxially arranged. The cylindrical tank body and the coaxially arranged conical sleeves form a symmetrical flow field structure, which is conducive to the formation of a stable and uniform vortex of the vapor-liquid mixture in the annular channel, avoiding flow deviation or dead zones, thereby ensuring the stability and consistency of the flash evaporation and separation process. The arrangement of steam outlet at the top center and liquid outlet at the bottom conforms to the natural distribution of gravity and centrifugal force fields, making the process smooth.

[0044] See Figure 1 and 2 The conical sleeve 2 has at least three layers, with adjacent layers forming several annular flash channels. The diameter of each annular flash channel gradually increases from the inside to the outside. Preferably, the conical sleeve 2 has 2-5 layers. By setting multiple layers of conical sleeves, the effective flash surface area and separation path are greatly increased within the limited tank space. The fluid swirls from the inside to the outside, achieving a progressively enhanced multi-stage vaporization and separation process. This improves the processing efficiency of a single unit while maintaining a compact structure.

[0045] See also Figure 1 and 2The shape of the conical sleeve 2 matches the shape of the flash evaporation channel. The conical sleeve 2 has a conical section, and the cone angle of the conical section in each layer of the conical sleeve 2 is consistently upward. The cone angle is relatively small, optionally between 15 and 45 degrees. This consistent cone angle direction causes the cross-sectional area of ​​all annular flash evaporation channels to gradually decrease from top to bottom. According to fluid mechanics principles, when the swirling fluid enters the converging channel, its velocity increases, significantly enhancing the centrifugal force field. This facilitates the throwing of denser droplets towards the sleeve wall, achieving efficient gas-liquid separation, and is key to resolving the "preventing entrainment" problem.

[0046] For the specific connection method between the conical sleeve 2 and the tank body 1, please refer to [link / reference]. Figure 1 and 2 The upper ends of each of the conical sleeves 2 are flush with each other. The upper ends of the conical sleeves 2 are connected to the inner wall of the tank body 1 by support ribs 9. Furthermore, the support ribs 9 are arranged radially along the conical sleeves 2, and there are multiple support ribs 9 arranged at intervals along the circumference of the conical sleeves 2. By fixing the upper ends of the multi-layer sleeves to the tank wall through radial support ribs, a stable internal skeleton structure is formed, ensuring the coaxiality and positional accuracy of each layer of sleeves under fluid impact and temperature changes, thereby ensuring the stability of the flow field.

[0047] In this embodiment, the conical sleeve 2 is provided with 3 layers, and the tank body 1 is fixedly installed with 3 layers of concentrically arranged conical sleeves 2 by radial support ribs 9.

[0048] The conical sleeve 2 includes a vertical part and a conical part connected sequentially from top to bottom, wherein the vertical part is a cylinder and the conical part is a truncated cone with the cone angle pointing upward. The connection positions of the vertical part and the conical part are flush, and the connection points of the vertical part and the conical part of each layer of the conical sleeve 2 are flush.

[0049] The output end of the liquid distributor 5 is positioned corresponding to the vertical section. The upper cylindrical vertical section provides an ideal initial liquid distribution and film-forming zone for the liquid distributor, allowing hot water to smoothly spread into a liquid film and begin flash evaporation. The lower conical section focuses on swirling acceleration and centrifugal separation. This combination of vertical and conical sections optimizes the spatial allocation of the "vaporization initiation" and "separation enhancement" stages, making the entire process more efficient and controllable.

[0050] See also Figure 1 Each conical sleeve 2 has a porous sintered flash layer 3 on its inner and outer walls through a plasma spraying process.

[0051] Optionally, the sintered flash layer 3 is made of sintered stainless steel or sintered ceramic. Preferably, the sintered flash layer 3 is made of 316L stainless steel with an average pore size between 10 and 50 micrometers. The sintered metal layer formed by plasma spraying has a rich and stable microporous structure. These micropores provide a large number of vaporization nuclei for liquid flash evaporation, which can greatly promote and enhance the initial vaporization process, thereby fundamentally improving flash evaporation efficiency.

[0052] See Figure 1 and 3 A liquid inlet 4 is provided on the middle wall of the tank body 1. A liquid distributor 5 is connected to the liquid inlet 4. The output end of the liquid distributor 5 is suspended inside the multi-layer conical sleeve 2. The liquid tangential distributor 5 is a tubular structure with several distribution grooves on its tube wall. Specifically, tangential slots of different areas are provided on the lower part of the tube wall of the liquid distributor 5. The key function of the tangential slots on the tubular distributor is to efficiently convert the linear flow of high-pressure hot water into tangential rotational flow along the sleeve wall. Slots of different areas can be adapted to sleeves at different radial positions to achieve reasonable distribution of liquid volume. The size of each tangential slot gradually increases towards the end of the liquid tangential distributor 5 along its length. For details, see [link to details]. Figure 4 and 5 The tangential slit groove at the end of the liquid tangential distributor 5 along its length serves as the first liquid outlet, with a high liquid pressure. The pressure at subsequent outlets decreases sequentially. If it is necessary to adjust the liquid flow rate entering each sleeve layer, this can be achieved by adjusting the depth of the slit groove. The slit structure helps to form a thin and uniform tangential liquid film, providing ideal initial conditions for subsequent swirl flash evaporation.

[0053] See Figure 1 The upper part of the tank body 1 is equipped with a wire mesh demister 8, which is located between the steam outlet 6 and the conical sleeve 2. As the final fine separation device, the wire mesh demister can capture the extremely fine droplets that may remain after multi-layer cyclone separation, ensuring that the steam discharged from the steam outlet has extremely high dryness, meeting the requirements of subsequent steam compressors and other equipment for intake air quality.

[0054] In summary, during operation, high-temperature pressurized hot water enters at high speed from the inlet 4 under pressure and is evenly spread onto the sintered flash evaporation layer 3 of each conical sleeve 2 through the liquid distributor 5, forming a rotating thin liquid film. The liquid flashes violently at the micropores of the sintered flash evaporation layer 3, generating a large amount of steam. Based on the shape of the flash evaporation channel itself and its multi-layered nested structure, the vapor-liquid mixture moves in a spiral motion along the annular flash evaporation channel between the conical sleeves 2 and the circular flash evaporation channel inside the innermost conical sleeve 2 under the initial momentum of the tangential liquid entry. The vapor-liquid mixture spirals downward and passes through each flash evaporation channel from the inside to the outside step by step.

[0055] During this process, denser droplets are continuously thrown against the wall of the conical sleeve 2 under centrifugal force and fall along the wall. Bubbles diffuse to the surface, and dry steam gathers in the center of the flash evaporation channel and moves upward. After passing through the wire mesh demister 8, the steam achieves efficient gas-liquid separation.

[0056] Dry steam is discharged from the steam outlet 6 at the top of tank 1, and the separated cooling water is collected at the bottom of tank 1 and discharged through the liquid phase discharge pipe 7.

[0057] In summary, this multi-stage conical vortex flash evaporator integrates a sintered flash layer 3 with high-efficiency vaporization and a multi-layer flash channel with vortex separation, allowing the vaporization process of hot water to occur on the separation surface, while the separation process continuously creates new vaporization surfaces. The synergistic effect of vaporization and separation depths achieves spatiotemporal coupling and mutual promotion of the two processes, fundamentally solving the problem of low recovery efficiency caused by setting vaporization and separation as two independent stages in existing technologies.

[0058] Among them, the sintered flash evaporation layer 3 provides a stable and massive vaporization core, ensuring an extremely high initial vaporization rate; the multi-layer swirling liquid film in the flash evaporation channel has a large area, a thin liquid layer, a short bubble diffusion path, and strong centrifugal force, which effectively prevents droplet entrainment and ensures the high dryness of the outlet steam.

[0059] Within the limited space of the tank 1, radially stacked conical sleeves 2 are set up, which improves the effective vaporization surface area and separation path length, making the flash tank 1 small in size, highly efficient, and with a large processing capacity.

[0060] This multi-stage conical vortex flash evaporator has no moving parts inside. The conical sleeve 2 has a robust structure, and the sintered metal layer is corrosion-resistant, high-temperature resistant, and has a long overall service life. It can adapt to fluctuations in operating conditions, ensuring the stable and reliable operation of the flash evaporator.

[0061] The embodiments described above are only used to illustrate the technical ideas and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. The scope of patent application of the present invention should not be limited by these embodiments. That is, any equivalent changes or modifications made in accordance with the spirit disclosed in the present invention still fall within the patent scope of the present invention.

Claims

1. A multi-stage conical vortex flash evaporator, comprising a vertical tank body (1), characterized in that, The tank (1) is provided with a steam discharge section at the top and a liquid discharge section at the bottom; Several layers of conical sleeves (2) are vertically arranged inside the tank body (1). Each layer of conical sleeves (2) is arranged sequentially from the inside to the outside. The conical sleeves (2) of adjacent layers and the inside of the innermost conical sleeve (2) form a flash evaporation channel that is connected vertically. The radial section of the flash evaporation channel is circular or annular, and its diameter gradually decreases from top to bottom. A heatable sintered flash evaporation layer (3) is provided on the side of the conical sleeve (2) facing the flash evaporation channel. Liquid distributor (5) is provided with a plurality of output terminals corresponding to the upper part of each of the flash channels, and the output direction of the output terminals is set along the tangential direction of the flash channels.

2. A multi-stage conical vortex flash evaporator according to claim 1, characterized in that, The flash evaporation channels, from the inside out, have their lower openings arranged sequentially at intervals from top to bottom.

3. A multi-stage conical vortex flash evaporator according to claim 1, characterized in that, The conical sleeve (2) is provided with at least 3 layers, and the conical sleeves (2) of adjacent layers form several layers of annular flash channels, and the diameter of each layer of annular flash channels gradually increases from the inside to the outside.

4. A multi-stage conical vortex flash evaporator according to claim 1, characterized in that, The vertical tank (1) is cylindrical; a steam outlet (6) is provided at the center of the top of the tank (1), and the steam outlet (6) forms the steam discharge section; a liquid phase discharge pipe (7) is provided at the bottom of the tank (1), and the liquid phase discharge pipe (7) forms the liquid phase discharge section; The conical sleeves (2) and the tank body (1) of each layer are coaxially arranged.

5. A multi-stage conical vortex flash evaporator according to claim 1, characterized in that, The shape of the conical sleeve (2) matches the shape of the flash evaporation channel. The conical sleeve (2) is provided with a conical part, and the cone angle of the conical part in each layer of the conical sleeve (2) is always upward.

6. A multi-stage conical vortex flash evaporator according to claim 5, characterized in that, The conical sleeve (2) includes a vertical part and a conical part connected sequentially from top to bottom, wherein the vertical part is a cylinder and the conical part is a truncated cone with the cone angle pointing upward. The connection positions of the vertical part and the conical part are flush, and the connection points of the vertical part and the conical part of each layer of the conical sleeve (2) are flush. The output end of the liquid distributor (5) is set in relation to the vertical part.

7. A multi-stage conical vortex flash evaporator according to claim 1, characterized in that, The upper ends of each of the conical sleeves (2) are flush with each other. The upper ends of the conical sleeves (2) are connected to the inner wall of the tank body (1) by support ribs (9). The support ribs (9) are arranged radially along the conical sleeves (2). There are multiple support ribs (9). The support ribs (9) are arranged sequentially at intervals along the circumference of the conical sleeves (2).

8. A multi-stage conical vortex flash evaporator according to claim 1, characterized in that, Each conical sleeve (2) has a porous sintered flash layer (3) on its inner and outer walls through a plasma spraying process.

9. A multi-stage conical vortex flash evaporator according to claim 1, characterized in that, A liquid inlet (4) is provided on the middle wall of the tank (1). The liquid distributor (5) is connected to the liquid inlet (4). The output end of the liquid distributor (5) is suspended inside the multi-layer conical sleeve (2). The liquid tangential distributor (5) is a tubular structure. The liquid distributor (5) has tangential slots of different areas on the lower part of its tube wall, wherein the size of each tangential slot gradually increases as it approaches the end of the liquid tangential distributor (5) in the length direction.

10. A multi-stage conical vortex flash evaporator according to claim 1, characterized in that, The upper part of the tank (1) is provided with a wire mesh demister (8), which is located between the steam outlet (6) and the conical sleeve (2).

Images