Integrated high-efficiency falling film concentration separator

Abstract

The integrated high-efficiency falling film concentration separator comprises a tower body, an upper tube plate is arranged at the upper end opening of the tower body, an upper tube box is arranged above the upper tube plate, and a tube pass feed liquid inlet is formed in the center of the top of the upper tube box; the upper end opening of the tower body is provided with an upper tube plate, the lower end opening of the tower body is provided with a lower tube plate, the upper tube plate and the lower tube plate are respectively and uniformly provided with a plurality of tube orifices, the upper and lower corresponding tube orifices are respectively connected through falling film tubes, a lower tube box is arranged below the lower tube plate, the bottom of the lower tube box is provided with a crystal mush outlet, and the side wall of the upper part of the lower tube box is provided with a secondary steam outlet; a shell pass steam inlet is formed in the upper side wall of the tower body, and a condensed water outlet is formed in the lower side wall of the tower body. The falling-film tube is a spiral falling-film tube with a long circular section, two ends of a long axis of each cross section are opposite semicircles, two ends of a short axis are parallel to each other, and the falling-film tube is continuously twisted into a spiral shape by taking the center line of the falling-film tube as an axis. The integrated high-efficiency falling film concentration separator is small in occupied area, high in heat transfer coefficient and low in shell pass resistance, and liquid films in the falling film pipes are uniformly distributed.

Description

Technical Field

[0001] The present invention relates to a falling film concentrating separator, in particular to an integrated high-efficiency falling film concentrating separator, which belongs to the technical field of concentrating equipment and is used for concentrating solutions containing inorganic salts or solids in the new energy or chemical wastewater industries. Background Art

[0002] The current mainstream technology in the market for concentration, purification and separation of chemical wastewater uses four independent devices: falling film evaporator, vapor-liquid separator, steam scrubber and thickener to respectively complete concentration, vapor-liquid separation, small droplet capture and clear liquid separation. The falling film evaporator uses ordinary light tubes, which has the following problems:

[0003] 1. Using multiple devices to perform different functions will result in high equipment costs, large floor space, and higher civil engineering costs.

[0004] 2. The shell side of an existing ordinary falling film evaporator requires a considerable number of bow-shaped baffles. The baffles have the following two functions: first, the falling film tubes need to be supported in the longitudinal direction to ensure that the shell-side fluid does not vibrate due to the Karman vortex street when flowing through the falling film tubes; second, they allow the shell-side fluid to pass through the tube bundle as longitudinally as possible. However, when the shell-side fluid passes through the top of each baffle in a wavy and zigzag manner, dead zones are formed in the triangular areas on both sides of the connection between the root of each baffle and the inner wall of the shell cylinder, reducing the effective heat exchange length and heat exchange area of ​​each falling film tube. The existence of each dead zone greatly affects the heat transfer efficiency. Furthermore, the disturbance of the shell-side steam by the traditional bow-shaped baffles is limited by factors such as material cost and shell-side resistance drop. The shell-side steam can only be deflected within a large range, and the number of deflections is also quite limited.

[0005] 3. The traditional vertical falling film evaporator adopts a light tube. When the shell side adopts steam condensation heating, the steam will form a condensation liquid film on the outer wall of the falling film tube after condensation. The liquid film will gradually thicken in the height direction of the falling film tube due to the effect of gravity, so the heat transfer effect is poor in the middle and lower parts of the falling film tube.

[0006] 4. When the shell-side fluid of the existing common falling film evaporator flows through the baffle notch area, the resistance will increase due to the reduction of the flow area.

[0007] 5. Existing ordinary falling film evaporators require a larger falling film tube center distance to reduce the resistance of the shell-side fluid and ensure that the shell-side resistance drop meets the process requirements. This limits the heat exchanger shell to a larger diameter and increases the material cost.

[0008] 6. The thickness of the liquid film in the falling film tube of the existing ordinary falling film evaporator is poorly uniform in the circumferential direction. In order to ensure the uniform thickness of the liquid film in the circumferential direction of the falling film tube, the film distributor must have a good film spreading effect and the falling film tube bundle must be manufactured and installed with high vertical accuracy. Otherwise, the tube-side fluid will fall more evenly on the tube bridge of the upper tube plate after passing through the specially structured film distributor. During the process of flowing downward along the falling film tube, the unevenness of the liquid film in the falling film tube in the circumferential direction may be amplified due to deviations in the manufacturing and installation of the heat exchanger, thereby affecting the heat transfer effect. Furthermore, when the deviation of the liquid film in the falling film tube reaches a certain level, the liquid film thickness may decrease to zero on one side, thereby causing dryness in some areas of the falling film tube, scaling, and further blockage of the falling film tube.

[0009] 7. The liquid distribution plate of the traditional falling film evaporator adopts a porous structure, and the number of holes is generally 1.1 to 1.5 times the number of falling film tubes. In addition, the structure of the preliminary liquid distributor + single-stage film distributor is generally adopted. In order to distribute the liquid evenly, the number of liquid distribution holes is difficult to reduce, which results in the relatively small diameter of the liquid distribution holes. In the concentration process of inorganic salt solutions or other solutions containing solids, it is easy to scale on the surface of the liquid distribution plate. When the scale reaches a certain thickness, it will form a bridge to block the liquid distribution holes, thereby causing the falling film tubes of the falling film evaporator to be blocked and unable to operate normally. Summary of the Invention

[0010] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of the invention of this application, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0011] In view of the above problems and / or the problems existing in the prior art, the present invention is proposed.

[0012] The purpose of the present invention is to overcome the problems existing in the prior art and provide an integrated high-efficiency falling film concentrator separator with a small footprint, high heat transfer coefficient, low shell-side resistance, and uniform liquid film distribution in the falling film tube.

[0013] In order to solve the above technical problems, the present invention provides an integrated high-efficiency falling film concentrator separator, including a tower body, wherein the upper port of the tower body is provided with an upper tube plate, an upper tube box is provided above the upper tube plate, and a tube-side liquid inlet is provided at the top center of the upper tube box; the lower port of the tower body is provided with a lower tube plate, and a plurality of pipe openings are evenly distributed on the upper tube plate and the lower tube plate, respectively, and the upper and lower corresponding pipe openings are respectively connected by falling film tubes, a lower tube box is provided below the lower tube plate, a slurry outlet is provided at the bottom of the lower tube box, and a secondary steam outlet is provided on the upper side wall of the lower tube box; a shell-side steam inlet is provided on the upper side wall of the tower body, and a condensate outlet is provided on the lower side wall of the tower body.

[0014] As an improvement of the present invention, a liquid collecting and guide tube is connected below the lower tube plate, and the liquid collecting and guide tube includes a large diameter section of the guide tube, a conical section of the guide tube and a small diameter section of the guide tube from top to bottom. The upper port of the lower tube box is connected to the lower outer periphery of the large diameter section of the guide tube.

[0015] As a further improvement of the present invention, a swirl blade is provided in the middle cross-section of the inner cavity of the small diameter section of the guide tube. When the vapor-liquid mixture flowing out of the lower tube plate flows from the large diameter section of the guide tube to the small diameter section of the guide tube, the axial flow velocity is accelerated, and when passing through the swirl blade, high-speed rotation is generated. Under the action of centrifugal force, small droplets entrained in the secondary steam collide with the inner wall of the small diameter section of the guide tube to form large droplets, and then fall along the tube wall, thereby reducing the amount of droplets entrained in the secondary steam.

[0016] As a further improvement of the present invention, a demister is provided in the annular section between the outer periphery of the small diameter section of the guide tube and the inner wall of the lower tube box, and an annular flushing device is provided above the demister. The nozzle of the flushing device is downward for regularly cleaning the demister; the flushing device is located below the secondary steam outlet.

[0017] As a further improvement of the present invention, a preliminary liquid separator coaxial with the liquid inlet of the tube side is provided below the inlet of the tube side, and a preliminary liquid separator is provided at the bottom of the preliminary liquid separator. The diameter of the preliminary liquid separator is 1 / 3 to 1 / 2 of the diameter of the upper tube plate, and a plurality of preliminary liquid separator holes are evenly arranged thereon; the outer periphery of the preliminary liquid separator is provided with an upwardly erected preliminary liquid separator cylinder, and the circumferential outer wall of the preliminary liquid separator cylinder is suspended below the top wall of the upper tube box by a plurality of suspension rods.

[0018] As a further improvement of the present invention, a plurality of preliminary liquid separation grooves are evenly provided on the lower circumference of the preliminary liquid separation cylinder, each preliminary liquid separation groove extends vertically upward, and the lower edge of the preliminary liquid separation groove is flush with the top surface of the preliminary liquid separation plate.

[0019] As a further improvement of the present invention, a first-level liquid distributor is provided directly below the preliminary liquid distributor, and a first-level liquid distribution tray is provided at the bottom of the first-level liquid distributor; a plurality of first-level liquid distribution holes are evenly distributed on the first-level liquid distribution tray, and an upwardly erected first-level liquid distribution cylinder is provided on the outer periphery of the first-level liquid distribution tray.

[0020] As a further improvement of the present invention, a secondary film distributor is provided directly below the primary liquid distributor, and a secondary liquid distribution tray is provided at the bottom of the secondary film distributor. A plurality of secondary liquid distribution holes are evenly distributed on the secondary liquid distribution tray, and an upwardly erected secondary liquid distribution cylinder is provided on the outer periphery of the secondary liquid distribution tray.

[0021] As a further improvement of the present invention, each secondary liquid distribution hole on the secondary liquid distribution tray is respectively provided with a tooth-shaped liquid distribution unit, the middle part of each tooth-shaped liquid distribution unit is embedded in the corresponding secondary liquid distribution hole and welded and fixed, and the upper circumference of each tooth-shaped liquid distribution unit is symmetrically provided with three V-shaped overflow grooves that are wide at the top and narrow at the bottom, and the bottom of each V-shaped overflow groove is flush with the upper surface of the secondary liquid distribution tray; the lower circumference of each tooth-shaped liquid distribution unit is symmetrically provided with three V-shaped drooping parts that extend downward and are wide at the top and narrow at the bottom, and each V-shaped drooping part is located directly below the corresponding V-shaped overflow groove.

[0022] As a further improvement of the present invention, the adjacent tube openings of the upper tube plate are distributed in an equilateral triangle, and every three falling film tubes correspond to one tooth-shaped liquid distribution unit. The circumference of each tooth-shaped liquid distribution unit is located above the center of the three falling film tubes, and each V-shaped drooping part of the tooth-shaped liquid distribution unit points to the center point of the tube bridge between the three falling film tubes for liquid distribution.

[0023] As a further improvement of the present invention, the center line of each first-level liquid distribution hole on the first-level liquid distribution plate is located between two adjacent tooth-shaped liquid distribution units.

[0024] As a further improvement of the present invention, the falling film tube is a spiral falling film tube with an oblong cross-section, the two ends of the long axis of each cross section are semicircular and facing each other, the two ends of the short axis are parallel to each other, and the tube is continuously twisted into a spiral with the center line of the falling film tube as the axis.

[0025] As a further improvement of the present invention, the major axis and minor axis of each oblong cross-section spiral falling film tube are parallel to each other, and the gaps between each row of oblong cross-section spiral falling film tubes in the minor axis direction constitute the shell-side medium channel.

[0026] As a further improvement of the present invention, the center distances between adjacent oblong cross-section spiral falling film tubes are equal to the length of the long axis, so that the adjacent oblong cross-section spiral falling film tubes are tangentially contacted with each other through the two end points of the long axis to achieve self-support.

[0027] As a further improvement of the present invention, the center line of each oblong cross-section spiral falling film tube remains unchanged during the spiral process, and it makes tangential contact with the adjacent oblong cross-section spiral falling film tube six times within 360° of each pitch, and the position of the tangential contact point with the adjacent oblong cross-section spiral falling film tube changes every 60°.

[0028] As a further improvement of the present invention, the outer circumference of the spiral falling film tube bundle with an oblong cross-section is a dodecagon, and the outer circumference is tied with multiple straps.

[0029] As a further improvement of the present invention, the cross-sectional dimensions of each oblong cross-section spiral falling film tube are 45x25.5mm, and the spiral pitch is 250mm; the upper and lower ends of each oblong cross-section spiral falling film tube are circular base tubes with an outer diameter of 38mm.

[0030] As a further improvement of the present invention, a clear liquid overflow device is installed at the bottom center of the lower pipe box, and the clear liquid overflow device includes an umbrella-shaped cover and a cone bucket coaxial with the lower pipe box, a pressure-balancing elbow is provided at the cone top center of the umbrella-shaped cover, and the lower port of the umbrella-shaped cover is provided with a cylinder extending vertically downward; the cone bucket is a structure with a larger upper portion and a smaller lower portion and the upper end is located in the inner cavity of the umbrella-shaped cover, and the outer wall of the upper port of the cone bucket is connected to the inner wall of the cylinder of the umbrella-shaped cover through a plurality of symmetrically arranged ribs, the bottom of the cone bucket is supported on the bottom of the lower pipe box, and the lower end of the cone bucket is connected to an overflow clear liquid outlet extending out of the lower pipe box; the concentrated liquid enters the lower pipe box for sedimentation and separation, and the concentrated liquid containing crystal slurry particles with a higher density is discharged from the crystal slurry outlet at the bottom of the lower pipe box, and the clear liquid with a lower density floats up from the annular space between the umbrella-shaped cover cylinder and the upper end of the cone bucket and enters the cone bucket, and then is discharged from the overflow clear liquid outlet.

[0031] As a further improvement of the present invention, a tower body bracket is welded to the upper circumferential outer wall of the tower body, and a tower top hanging column is fixed on the tower body bracket. The upper end of the tower top hanging column is bent toward the center line of the tower top and is provided with an upper pipe box lifting lug for facilitating lifting the upper pipe box; the upper circumferential outer wall of the tower body is also symmetrically provided with a plurality of tower body lifting lugs.

[0032] Compared with the prior art, the advantages or beneficial effects achieved by the embodiments of the present application include at least: 1. A compact combination structure is adopted to integrate the original four devices into one device, reducing the site area occupied by more than 50%; and there is no need to set up a vapor-liquid separator, a vertical steam scrubber and a thickener, which saves the material cost required to build these two devices; at the same time, the original three devices need to be connected to each other through pipes and flanges, etc., and this part of the material cost is also saved; in addition, the original connection of these four devices through pipes and flanges has the risk of pipe welding and flange connection leakage. Now that these pipes and flanges have been eliminated, the reliability of the device is also increased.

[0033] 2. The shell-side baffles are eliminated, which saves the material cost and machining cost of the baffles; at the same time, there is no need to set tie rods and distance tubes, saving material costs;

[0034] 3. The smaller falling film tube center distance is adopted. Under the condition of the same heat exchange area, the diameter of the tube bundle is smaller, which means that thinner tower body and upper and lower tube sheets can be used. The tube sheets and tower body can be reduced in diameter and thickness, saving material costs.

[0035] 4. Using an oblong-section spiral falling film tube as the falling film tube. The unique structure of the oblong-section spiral falling film tube prevents the liquid film formed during the shell-side condensation of the heated steam from continuously thickening as in a traditional falling film evaporator, thereby reducing the thickness of the thermal boundary layer outside the falling film tube and reducing the heat transfer resistance between the steam and the outer wall of the falling film tube. At the same time, the spiral structure of the inner wall of the falling film tube makes the liquid film thickness on the inner wall of the tube more uniform through secondary distribution. At the same time, the secondary flow in the circumferential direction also makes the thermal boundary layer thickness of the liquid film inside the falling film tube more uniform, thereby improving the heat transfer coefficient on the tube side. The comprehensive improvement of the heat transfer efficiency inside and outside the tube increases the total heat transfer coefficient of the integrated high-efficiency falling film evaporation separator from 1600W / (㎡·k) of the traditional falling film evaporator to more than 2100W / (㎡·k), an increase of more than 31% in heat transfer coefficient.

[0036] 5. Due to the circumferential secondary flow generated by the oblong cross-section spiral falling film tube on the inner wall of the tube, the flow boundary layer velocity of the liquid film in the tube is faster, and the scaling period of the inner wall of the oblong cross-section spiral falling film tube is longer, which means that a lower tube fouling thermal resistance can be selected in thermal calculation;

[0037] 6. A liquid collecting guide tube is installed at the bottom of the lower tube box. The inner cavity of the small diameter section of the guide tube is equipped with swirl blades. When the steam-liquid mixture coming out of the lower tube plate flows from the large diameter section of the guide tube to the small diameter section of the guide tube, the cross section decreases and the axial flow velocity accelerates. When passing through the swirl blades, high-speed rotation is generated. Under the action of centrifugal force, small droplets entrained in the secondary steam collide with the inner wall of the small diameter section of the guide tube to form large droplets, which then fall along the tube wall. This reduces the amount of droplets entrained in the secondary steam.

[0038] 7. A clear liquid separation device is installed at the bottom of the integrated high-efficiency falling film evaporation separator, which can replace the thickener. The unique overflow structure makes the separation of the concentrated salt solution and clear liquid better, and the salt solid particle content in the clear liquid is significantly reduced compared with the traditional vapor-liquid separator;

[0039] 8. The film distributor on the top adopts a multi-stage structure of preliminary liquid distributor + first-level liquid distributor + second-level film distributor. Through the specially designed tooth-shaped liquid distribution unit, the chemical cleaning cycle of the falling film evaporator can be greatly extended and the difficulty of chemical cleaning is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. The drawings are only provided for reference and illustration, and are not used to limit the present invention.

[0041] in:

[0042] Figure 1 This is a front view of the integrated high-efficiency falling film concentrating separator of the present invention;

[0043] Figure 2 for Figure 1 Left view of;

[0044] Figure 3 1. An exploded view of the multi-stage liquid distribution mechanism of the present invention;

[0045] Figure 4 This is a three-dimensional enlarged view of the secondary membrane distributor;

[0046] Figure 5 This is a three-dimensional enlarged view of the tooth-shaped liquid distribution unit in the secondary film distributor;

[0047] Figure 6 A top view of the upper tube plate and the tooth-shaped liquid distribution unit above it in the present invention;

[0048] Figure 7 A three-dimensional diagram of a spiral falling film tube bundle with an outer circular cross section in the present invention;

[0049] Figure 8 A perspective view of a spiral falling film tube with an oblong cross section according to the present invention;

[0050] Figure 9 Schematic diagram of the transformation of the spiral falling film tube bundle with an oblong cross-section from the supporting point in the present invention;

[0051] Figure 10 It is a cross-sectional view of the clear liquid overflow device in the present invention;

[0052] In the figure: 1. Tower top davit; 1a. Upper tube box lifting lug;

[0053] 2. Upper pipe box; 2a. Pipeline liquid inlet;

[0054] 3. Preliminary liquid dispenser; 3a. Preliminary liquid dispensing plate; 3b. Preliminary liquid dispensing tank;

[0055] 4. First-stage liquid distributor; 5. Second-stage film distributor;

[0056] 6. Tooth-shaped liquid distribution unit; 6a. V-shaped overflow trough; 6b. V-shaped hanging part;

[0057] 7. Upper tube sheet; 8. Long circular cross-section spiral falling film tube; 9. Band;

[0058] 10. Tower body; 10a. Shell-side steam inlet; 10b. Condensate outlet; 10c. Tower body lifting lug;

[0059] 11. Lower tube plate; 12. Liquid collecting guide tube; 13. Swirl blades;

[0060] 14. Lower tube box; 14a. Secondary steam outlet; 14b. Slurry outlet;

[0061] 15. Defoamer; 16. Flushing device;

[0062] 17. Clear liquid overflow device; 17a. Umbrella-shaped cover; 17b. Pressure-balancing elbow; 17c. Rib plate; 17d. Conical bucket; 17e. Overflow clear liquid outlet. DETAILED DESCRIPTION

[0063] In the following description of the present invention, the terms "up", "down", "front", "back", "left", "right", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not mean that the device must have a specific direction.

[0064] In order to make the technical means, creative features, objectives and effects of the present invention easier to understand, the present invention is further described below with reference to specific figures. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them.

[0065] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention.

[0066] like Figure 1 、 Figure 2 As shown, the integrated high-efficiency falling-film evaporation separator of the present invention includes a tower body 10. An upper tube sheet 7 is provided at the upper end of the tower body 10. An upper tube box 2 is located above the upper tube sheet 7. A tube-side liquid inlet 2a is located at the top center of the upper tube box 2. A multi-stage film distribution device is located below the tube-side liquid inlet 2a. A lower tube sheet 11 is provided at the lower end of the tower body 10. Multiple nozzles are evenly distributed on each of the upper and lower tube sheets 7 and 11, and the corresponding nozzles are connected by falling-film tubes. A lower tube box 14 is located below the lower tube sheet 11. A slurry outlet 14b is located at the bottom of the lower tube box 14, and a secondary steam outlet 14a is located on the upper sidewall of the lower tube box 14. A shell-side steam inlet 10a is located on the upper sidewall of the tower body 10. The shell-side steam inlet 10a is located on the expanded diameter section at the upper end of the tower body to facilitate steam entry and uniform distribution. A condensate outlet 10b is located on the lower sidewall of the tower body 10.

[0067] Steam enters the tower through the shell-side steam inlet 10a at the top, enters the shell side, heats the falling film tubes, and releases its latent heat of vaporization as condensed water, which is then discharged through the condensed water outlet 10b at the bottom of the tower. A salt solution or other liquid enters the upper tube box 2 through the tube-side liquid inlet 2a. After being evenly distributed by the multi-stage film distribution device, it falls onto the upper tube sheet 7 and then evenly enters the falling film tubes, forming a falling film on the inner walls of each tube, increasing the specific surface area of ​​the liquid. The heating of the shell side rapidly evaporates the water or solvent, resulting in rapid concentration.

[0068] The upper circumferential outer wall of the tower body is symmetrically provided with a plurality of tower body lifting ears 10c to facilitate the lifting, positioning and installation of the tower body.

[0069] A tower body bracket is welded to the outer circumferential wall of the upper part of the tower body, and a tower top sling 1 is fixed on the tower body bracket. The tower top sling 1 is L-shaped, and the upper end is bent toward the center line of the tower top and is provided with an upper tube box lifting lug 1a. The upper tube box lifting lug 1a and the wire rope can be used to conveniently lift the upper tube box 2, which is convenient for cleaning dirt on the multi-stage film distribution device, and also for cleaning dirt in each falling film tube, or for maintenance and replacement.

[0070] like Figures 3 to 5 As shown, the multi-stage membrane distribution device of the present invention adopts a stacked structure of a preliminary liquid distributor 3, a primary liquid distributor 4, and a secondary membrane distributor 5. The preliminary liquid distributor 3 is located below the tube-side liquid inlet 2a and is coaxial with it. The bottom of the preliminary liquid distributor 3 is provided with a preliminary liquid distribution tray 3a. The outer periphery of the preliminary liquid distribution tray 3a is provided with an upwardly erected preliminary liquid distribution cylinder. The outer circumferential wall of the preliminary liquid distribution cylinder is suspended below the top wall of the upper tube box 2 by multiple suspension rods. The diameter of the preliminary liquid distribution tray 3a is 1 / 3 to 1 / 2 of the diameter of the upper tube plate, and multiple preliminary liquid distribution holes are evenly distributed thereon. Each preliminary liquid distribution hole only performs preliminary liquid distribution. Therefore, the aperture and flow rate of the preliminary liquid distribution holes are relatively large, and clogging is not easy to occur.

[0071] Multiple preliminary liquid separation grooves 3b are evenly distributed around the lower circumference of the preliminary liquid separation cylinder. Each preliminary liquid separation groove 3b extends vertically upward, with its lower edge flush with the top surface of the preliminary liquid separation plate 3a. While the preliminary liquid separation holes distribute liquid downward, the surrounding preliminary liquid separation grooves 3b also distribute liquid outward, distributing the liquid downward as evenly as possible.

[0072] A first-level liquid distributor 4 is provided directly below the preliminary liquid distributor 3, and a first-level liquid distribution tray is provided at the bottom of the first-level liquid distributor 4; a plurality of first-level liquid distribution holes are evenly distributed on the first-level liquid distribution tray, and an upwardly erected first-level liquid distribution cylinder is provided on the outer periphery of the first-level liquid distribution tray, and handles are symmetrically provided on the inner wall of the upper end of the first-level liquid distribution cylinder to facilitate installation and disassembly.

[0073] A secondary film distributor 5 is provided directly below the primary liquid distributor 4. A secondary liquid distributor pan is provided at the bottom of the secondary film distributor 5. A plurality of secondary liquid distribution holes are evenly distributed on the secondary liquid distribution pan. An upwardly erected secondary liquid distribution cylinder is provided on the outer periphery of the secondary liquid distribution pan. Handles are symmetrically provided on the inner wall of the upper end of the secondary liquid distribution cylinder.

[0074] A toothed liquid distribution unit 6 is provided in each secondary liquid distribution hole on the secondary liquid distribution tray. The middle part of each toothed liquid distribution unit 6 is embedded in the corresponding secondary liquid distribution hole and welded and fixed. Three V-shaped overflow grooves 6a, which are wide at the top and narrow at the bottom, are symmetrically provided on the upper circumference of each toothed liquid distribution unit 6. The bottom of each V-shaped overflow groove 6a is flush with the upper surface of the secondary liquid distribution tray; three V-shaped drooping parts 6b, which are wide at the top and narrow at the bottom, are symmetrically provided on the lower circumference of each toothed liquid distribution unit 6. Each V-shaped drooping part 6b is located directly below the corresponding V-shaped overflow groove 6a.

[0075] like Figure 6 As shown, the adjacent tube openings of the upper tube plate 7 are distributed in an equilateral triangle, and every three falling film tubes correspond to a tooth-shaped liquid distribution unit 6. The circumference of each tooth-shaped liquid distribution unit 6 is located above the center of the three falling film tubes, and each V-shaped drooping part 6b of the tooth-shaped liquid distribution unit 6 points to the center point of the tube bridge between the three falling film tubes for liquid distribution.

[0076] The center line of each first-level liquid distribution hole on the first-level liquid distribution plate is located between two adjacent tooth-shaped liquid distribution units 6. Although the first-level liquid distribution plate also adopts a porous structure, the number of first-level liquid distribution holes is approximately 30% of the number of falling film tubes. Therefore, the diameter of the first-level liquid distribution hole is also larger, and it is difficult to form a bridge blockage.

[0077] The liquid on the secondary liquid distribution plate overflows from each V-shaped overflow groove 6a to the inner cavity of the tooth-shaped liquid distribution unit 6, flows downward along its inner wall, and when it flows to the lower end of the V-shaped hanging part 6b, it is accurately distributed to the center point of the tube bridge between the three falling film tubes.

[0078] Each toothed liquid distribution unit 6 utilizes a toothed structure. This not only improves flowability and allows for a wide range of adjustable film flow rates, but also reduces the number of toothed liquid distribution units 6 to just one-third the number of falling film tubes. The diameter of each distribution unit is approximately 1.37-1.5 times the diameter of the falling film tube, virtually eliminating the possibility of bridging due to scaling. The tiny bridging structure formed at the lowest triangle of the V-shaped drooping portion 6b is self-cleaning due to the erosion of liquid flow (particularly for solutions containing solids), significantly extending the service life of the entire film distribution system.

[0079] Although the number of tooth-shaped liquid distribution units 6 is only 1 / 3 of the number of falling film tubes, it can still accurately ensure that three film distribution points are evenly distributed on the outer circumference of each falling film tube below, greatly improving the uniformity of film distribution.

[0080] The following improvements have been made to the inherent defects of the bow baffles: Figures 7 to 9 As shown, each falling film tube is changed from a plain tube to a spiral falling film tube 8 with an oblong cross-section, that is, the two sides of each falling film tube are parallel to each other, and the two ends are semicircular cross-sections facing each other. The straight line where the centers of the two semicircular cross-sections are located is the long axis of the falling film tube, and the short axis of the falling film tube is between the parallel two sides. The tube is continuously twisted into a spiral shape along the height direction with the center line of the falling film tube as the axis.

[0081] The major axis and minor axis of each oblong cross-section spiral falling film tube 8 are parallel to each other, that is, the phases of each oblong cross-section spiral falling film tube 8 on the cross section of the tower body are consistent; the gaps between each row of oblong cross-section spiral falling film tubes 8 in the minor axis direction constitute the shell-side medium channel.

[0082] The center distances between adjacent oblong cross-section spiral falling film tubes 8 are equal to the length of the long axis, so that the adjacent oblong cross-section spiral falling film tubes 8 are tangentially contacted with each other through the two end points of the long axis to achieve self-support. This avoids a series of problems caused by the use of bow-shaped baffles; at the same time, the self-support between the two end points of the long axis of the falling film tube can better avoid the vibration caused by the Karman vortex street. In addition, the shell-side steam can quickly pass through the entire length direction of the tube bundle because there is no obstruction of the bow-shaped baffles. Then, due to the effect of pressure, it overcomes the flow resistance and flows to the center area and the other side of the tube bundle. There is no dead zone in the entire flow process of the shell side, and the heat transfer efficiency is greatly improved compared to the traditional tube bundle. Compared with the bow-shaped baffles, the flow of the shell-side gas of the falling film tube bundle is disturbed in the circumferential direction due to the spiral space formed between the tube bundles, and the number of disturbances is Figure 7 For example, the tube bundle in the embodiment can achieve 38 perturbations, or 38 turns of the spiral. Compared to the approximately 5 to 8 perturbations of conventional bowed baffles, the shell-side flow disturbance is significantly better, with corresponding increases in turbulence and shell-side Reynolds number. Because bowed baffles are not installed, the flow cross-sectional area remains unchanged, and the shell-side resistance is much lower than that of a tube bundle with bowed baffles. During the shell-side steam flow, there are no dead zones on either side of the base of the bowed baffles, and the entire perimeter of the oblong-cross-section spiral falling-film tube represents effective heat exchange area.

[0083] like Figure 9As shown, the oblong spiral falling-film tubes are arranged in an equilateral triangle, with their centerlines remaining constant throughout the spiraling process. Within each 360° pitch, they make tangential contact with adjacent oblong spiral falling-film tubes six times, with the locations of these tangential contact points shifting every 60°. These contact points provide self-support, and multiple straps 9 are tied around the outer perimeter of the tube bundle to secure the bundle together. The bundle is arranged in a specially designed dodecagonal pattern, maximizing the circular area of ​​the upper tube sheet 7 while perfectly matching the toothed liquid distribution unit 6 above. The straps 9 contact the outermost layer of falling-film tubes in the bundle, ensuring mutual support between all the tubes at these contact points. This eliminates the need for traditional bow-shaped baffles to secure the bundle, allowing precise positioning of the oblong spiral falling-film tubes. Furthermore, the shell-side fluid automatically redirects along the flow paths between the oblong spiral falling-film tubes. When the shell-side fluid flows through the gaps between the falling film tubes, heat transfer occurs with the condensation film on the wall of the falling film tube. Since the process length is greatly shortened, the shell-side resistance is much lower than that of the traditional structure, and the distribution of resistance along the height direction of the tube bundle is also more uniform.

[0084] Taking 0° as an example, the shell-side steam first flows along the vertical channel. When it reaches 60°, the shell-side steam flows along the inclined channel. The following is similar, so that the flow channel of the shell-side steam is constantly switching, forming a continuous disturbance to the shell-side fluid, so that the steam is always in a turbulent state, thereby improving the heat exchange efficiency.

[0085] When shell-side steam condenses on the outer wall of the falling-film tubes to form a liquid film, it falls down the outer wall due to gravity, and periodically disturbs the contact points with the surrounding falling-film tubes. This keeps the thickness of the condensate film within a relatively small range, significantly improving the shell-side film heat transfer coefficient compared to bare tubes. Furthermore, the steam inlet method adopted by the present invention is to introduce steam from the upper middle part and discharge condensate from the bottom. As the steam flows downward along the spiral flow path formed between the falling-film tubes, it accelerates the downward flow of the condensate film.

[0086] Because the oblong-cross-section spiral falling-film tubes achieve self-support through their contact points with surrounding falling-film tubes, the center-to-center distance between adjacent falling-film tubes can be directly set to the long axis of the cross-section. This significantly reduces the center-to-center distance between falling-film tubes compared to traditional falling-film evaporators. Because there are no baffles to disturb the flow, the resistance drop of the shell-side fluid is also lower than that of traditional falling-film evaporators, significantly improving the heat transfer rate per unit shell-side resistance drop. Furthermore, the reduced shell diameter allows for reductions in parameters such as tubesheet diameter, tubesheet thickness, and tube box flange thickness, significantly reducing material costs.

[0087] When the tube-side fluid passes through the secondary film distributor 5 and falls on the center of each tube bridge of the upper tube plate 7, even if the manufacturing and installation of the heat exchanger cause the verticality of the falling film tube to deviate, it will not affect the uniformity of the liquid film thickness in the circumferential direction of the tube; when the liquid film falls along the inner wall of the falling film tube, due to the effect of the spiral, the liquid film will autonomously form a secondary distribution in the circumferential direction, which offsets the negative impact of the verticality deviation of the falling film tube, and greatly improves the tube-side heat transfer coefficient. At the same time, it can also better prevent scaling problems caused by dry pipes in the falling film tube.

[0088] Each oblong spiral falling-film tube has a 38mm outer diameter circular base tube at its upper and lower ends, facilitating insertion into the upper and lower tube sheets 7 and 11. Each oblong spiral falling-film tube has cross-sectional dimensions of 45 x 25.5 mm, with a spiral pitch of 250 mm. These dimensions were determined after multiple considerations: first, processing a 38mm outer diameter circular base tube to a 45mm cross-sectional major axis yields a yield exceeding 99% in the special-shaped tube manufacturing process; second, when the cross-sectional major axis is set at 45 mm, the cross-sectional area formed by the gaps between the oblong spiral falling-film tubes accounts for 43.4% of the cross-sectional area of ​​the entire tube bundle (within the dodecagon). Taking the tube bundle application conditions shown in this embodiment as an example, the cross-sectional flow rate of the shell-side steam is 4.5 m / s, and the shell-side resistance is approximately 52 kPa. The shell-side membrane heat transfer coefficient can reach above 3100 W / (㎡*K). This size is the optimal solution for the cross-sectional shape at this pitch. Specific data comparison is shown in the table below (assuming the heat exchange area and pitch are the same).

[0089] Spiral elliptical tube cross-section length (mm) Shell side flow rate m / s Shell side resistance drop kPa <![CDATA[Shell-side film heat transfer coefficient W / (m 2 *K)]]> 44 5.88 75 2933 45 4.92 52 3135 46 4.43 42 2836

[0090] As can be seen from the above table, under the most common working conditions of falling film evaporation of inorganic salt solutions or liquid materials containing solids in the biochemical industry, the best solution is to set the long axis of the spiral falling film tube to 45mm and the short axis to 25.5mm.

[0091] like Figure 1 、 Figure 2 and Figure 10 As shown, a liquid collecting and guiding tube 12 is provided in the lower separation section of the integrated high-efficiency falling film evaporation separator. The liquid collecting and guiding tube 12 is connected to the bottom of the lower tube plate 11. The liquid collecting and guiding tube 12 includes, from top to bottom, a guiding tube large-diameter section, a guiding tube conical section, and a guiding tube small-diameter section. The upper port of the lower tube box 14 is connected to the lower outer periphery of the guiding tube large-diameter section.

[0092] A swirl blade 13 is provided in the middle cross section of the inner cavity of the small diameter section of the guide tube. When the vapor-liquid mixture flowing out of the lower tube plate 11 flows from the large diameter section of the guide tube to the small diameter section of the guide tube, the axial flow velocity is accelerated. When passing through the swirl blade 13, high-speed rotation is generated. Under the action of centrifugal force, small droplets entrained in the secondary steam collide with the inner wall of the small diameter section of the guide tube to form large droplets, which then fall along the tube wall, thereby reducing the amount of droplets entrained in the secondary steam.

[0093] A demister 15 is provided in the annular section between the outer periphery of the small diameter section of the guide tube and the inner wall of the lower tube box 14. An annular flushing device 16 is provided above the demister 15. The nozzle of the flushing device 16 is downward for regularly cleaning the demister 15. The flushing device 16 is located below the secondary steam outlet 14a.

[0094] A clear liquid overflow device 17 is installed at the bottom center of the lower pipe box 14. The clear liquid overflow device 17 includes an umbrella-shaped cover 17a and a conical bucket 17d coaxial with the lower pipe box 14. A pressure-balancing elbow 17b is provided at the center of the cone top of the umbrella-shaped cover 17a, and a cylinder extending vertically downward is provided at the lower port of the umbrella-shaped cover 17a; the conical bucket 17d has a structure that is larger at the top and smaller at the bottom, and the upper end is located in the inner cavity of the umbrella-shaped cover 17a, and the outer wall of the upper port of the conical bucket 17d is connected to the inner wall of the cylinder of the umbrella-shaped cover 17a through a plurality of symmetrically arranged ribs 17c. The bottom of the conical bucket 17d is supported on the bottom of the lower pipe box 14, and the lower end of the conical bucket 17d is connected to an overflow clear liquid outlet 17e extending out of the lower pipe box 14. The concentrated liquid enters the lower pipe box 14 for sedimentation and separation. The concentrated liquid containing crystal slurry particles has a higher density and is discharged from the crystal slurry outlet 14b at the bottom of the lower pipe box 14. The clear liquid has a lower density and floats from the annular space between the umbrella-shaped cover cylinder and the upper end of the cone bucket 17d and enters the cone bucket 17d, and is then discharged from the overflow clear liquid outlet 17e.

[0095] The present invention integrates the functions of the original four devices into one in an integrated manner, realizing the concentration of feed liquid, vapor-liquid separation, small droplet capture in secondary vapor, and clear and turbid liquid separation in one device. It occupies a smaller area and has a lower steel structure cost. The number of flange connection points between devices is also greatly reduced, reducing material costs and leakage risks.

[0096] When the equipment is in operation, the liquid to be concentrated is preheated to the process temperature and enters the upper tube box 2 from the top pipe liquid inlet 2a, and then falls on the liquid distribution plate of the first-level liquid distributor 4 after being evenly distributed by the preliminary liquid separator 3. After staying on the liquid distribution plate for a short time, it flows downward and continues to fall on the liquid distribution plate of the second-level film distributor 5, and then falls on the tube bridge of the upper tube plate 7 after passing through the specially designed toothed liquid distribution unit 6; then due to gravity, it flows downward along the inner wall of the oblong cross-section spiral falling film tube to form a liquid film, but at this time the thickness of the liquid film is not uniform in the horizontal circumferential direction. In the process of the liquid flowing downward along the inner wall of the oblong cross-section spiral falling film tube, due to the unique spiral structure of the oblong cross-section spiral falling film tube, the liquid can generate secondary flow in the circumferential direction in the horizontal plane in addition to the vertical flow. Under the dual action of this secondary flow and the surface tension of the liquid itself, the thickness of the liquid film in the circumferential direction will become more uniform. Since this circumferential secondary flow exists in the entire height direction of the falling film tube, the adverse effects on the uniformity of the liquid film thickness caused by the vertical deviation of the tube bundle installation can be corrected at any time.

[0097] As the liquid film forms on the inner wall of the falling film tube, it reaches its boiling point due to the heat provided by the shell-side steam, partially vaporizing. The resulting secondary vapor rapidly flows downward along the inner wall of the falling film tube under the suction force of the secondary vapor outlet 14a. The liquid film on the inner wall of the oblong spiral falling film tube continues to flow downward and vaporize under the thrust of gravity and airflow. The resulting concentrated liquid and secondary vapor mixture flows out of the lower tube plate 11 and passes through the swirl vanes 13 in the lower section of the liquid collecting and guiding tube 12. Due to the centrifugal action of the swirl vanes 13, small droplets in the vapor-liquid mixture impact the tube wall, forming larger droplets that fall along the inner wall of the guiding tube. The liquid in the vapor-liquid mixture then settles by gravity in the liquid storage section at the bottom of the lower tube box 14. After the clear liquid is separated, the crystal slurry is discharged from the crystal slurry outlet 14b and sent to the centrifuge for separation. The clear liquid passes through the clear liquid overflow device 17 and flows out of the equipment through the overflow clear liquid outlet 17e for further concentration.

[0098] At the same time, the secondary steam in the vapor-liquid mixture flows out from the lower port of the liquid collecting guide tube 12 and then returns upward. A small amount of entrained droplets are captured when passing through the demister 15. The remaining relatively pure secondary steam enters the compressor through the pipeline from the secondary steam outlet 14a, where it is heated and pressurized. It then re-enters the shell-side space of the tube bundle through the shell-side steam inlet 10a, achieving recycling. Because there are no baffles in the shell-side space, the steam can quickly penetrate the entire shell-side space and then flow into the interior space of the tube bundle due to the steam pressure. During this process, the oblong-section spiral falling film tubes can support each other, thus avoiding the risk of falling film tube vibration caused by the Karman vortex street. The outermost tubes of the oblong-section spiral falling film tubes are arranged in a dodecagonal shape. Due to the provision of the band 9, the rigidity and strength of the entire tube bundle are guaranteed.

[0099] The shell-side steam condenses outside the oblong-section spiral falling film tube to form a condensation film, which flows downward along the outer wall of the oblong-section spiral falling film tube. When it encounters a contact point with the surrounding tubes, the condensation film converges on both sides of the contact point, which prevents the condensation film on the outer wall of the falling film tube below the contact point from continuing to thicken, thereby making the heat exchange between the shell-side steam and the oblong-section spiral falling film tube more sufficient; in the process of flowing through the channels between the tube bundles, the shell-side steam is constantly disturbed due to the unique shape of the oblong-section spiral falling film tube, which also makes the shell-side heat transfer film coefficient higher; the condensation film flows downward along the outer wall of the oblong-section spiral falling film tube to the bottom of the falling film tube and is discharged outside the equipment through the condensate outlet 10b.

[0100] The above description is only a preferred embodiment of the present invention, which shows and describes the basic principles, main features and advantages of the present invention, but does not limit the scope of patent protection of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. In addition to the above embodiments, the present invention may have other implementation modes without departing from the spirit and scope of the present invention. The present invention may also have various changes and improvements, and all technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the present invention. The scope of protection required by the present invention is defined by the attached claims and their equivalents. Technical features not described in the present invention can be achieved by or using existing technologies, and will not be described here.

Claims

1. An integrated high-efficiency falling film concentrator separator, comprising a tower body, characterized in that: The upper port of the tower body is provided with an upper tube plate, an upper tube box is provided above the upper tube plate, and a tube-side liquid inlet is provided at the top center of the upper tube box; the lower port of the tower body is provided with a lower tube plate, and a plurality of pipe openings are evenly distributed on the upper tube plate and the lower tube plate, respectively, and the upper and lower corresponding pipe openings are connected by falling film tubes, a lower tube box is provided below the lower tube plate, a slurry outlet is provided at the bottom of the lower tube box, and a secondary steam outlet is provided on the upper side wall of the lower tube box; a shell-side steam inlet is provided on the upper side wall of the tower body, and a condensate outlet is provided on the lower side wall of the tower body.

2. The integrated high-efficiency falling film concentrator separator according to claim 1, characterized in that: A liquid collecting and guiding tube is connected below the lower tube plate. The liquid collecting and guiding tube includes a guiding tube large diameter section, a guiding tube conical section and a guiding tube small diameter section from top to bottom. The upper port of the lower tube box is connected to the lower outer periphery of the guiding tube large diameter section.

3. The integrated high-efficiency falling film concentrator separator according to claim 2, characterized in that: A swirl blade is provided in the middle cross section of the inner cavity of the small diameter section of the guide tube. When the vapor-liquid mixture flowing out of the lower tube plate flows from the large diameter section of the guide tube to the small diameter section of the guide tube, the axial flow velocity is accelerated. When passing through the swirl blade, high-speed rotation is generated. Under the action of centrifugal force, small droplets entrained in the secondary steam collide with the inner wall of the small diameter section of the guide tube to form large droplets, and then fall along the tube wall, thereby reducing the amount of droplets entrained in the secondary steam.

4. The integrated high-efficiency falling film concentrator separator according to claim 2, characterized in that: A demister is provided in the annular section between the outer periphery of the small diameter section of the guide tube and the inner wall of the lower tube box. An annular flushing device is provided above the demister. The nozzle of the flushing device is downward for regularly cleaning the demister. The flushing device is located below the secondary steam outlet.

5. The integrated high-efficiency falling film concentrator separator according to claim 1, characterized in that: A preliminary liquid separator is provided below the tube-side liquid inlet and is coaxial with the inlet. A preliminary liquid separator is provided at the bottom of the preliminary liquid separator. The diameter of the preliminary liquid separator is 1 / 3 to 1 / 2 of the diameter of the upper tube plate, and a plurality of preliminary liquid separator holes are evenly distributed thereon. An upwardly erected preliminary liquid separator cylinder is provided on the outer periphery of the preliminary liquid separator, and the circumferential outer wall of the preliminary liquid separator cylinder is suspended below the top wall of the upper tube box by a plurality of suspension rods.

6. The integrated high-efficiency falling film concentrator separator according to claim 5, characterized in that: A plurality of preliminary liquid separation grooves are evenly arranged on the lower circumference of the preliminary liquid separation cylinder, each preliminary liquid separation groove extends vertically upward, and the lower edge of the preliminary liquid separation groove is flush with the top surface of the preliminary liquid separation plate.

7. The integrated high-efficiency falling film concentrator separator according to claim 5, characterized in that: A first-level liquid distributor is provided directly below the preliminary liquid separator, and a first-level liquid distribution tray is provided at the bottom of the first-level liquid distributor; a plurality of first-level liquid distribution holes are evenly distributed on the first-level liquid distribution tray, and an upwardly erected first-level liquid distribution cylinder is provided on the outer periphery of the first-level liquid distribution tray.

8. The integrated high-efficiency falling film concentrator separator according to claim 7, characterized in that: A secondary film distributor is provided directly below the primary liquid distributor, and a secondary liquid distribution tray is provided at the bottom of the secondary film distributor. A plurality of secondary liquid distribution holes are evenly distributed on the secondary liquid distribution tray, and an upwardly erected secondary liquid distribution cylinder is provided on the outer periphery of the secondary liquid distribution tray.

9. The integrated high-efficiency falling film concentrator separator according to claim 7, characterized in that: A tooth-shaped liquid distribution unit is provided in each secondary liquid distribution hole on the secondary liquid distribution tray. The middle part of each tooth-shaped liquid distribution unit is embedded in the corresponding secondary liquid distribution hole and welded and fixed. Three V-shaped overflow grooves that are wide at the top and narrow at the bottom are symmetrically provided on the upper circumference of each tooth-shaped liquid distribution unit. The bottom of each V-shaped overflow groove is flush with the upper surface of the secondary liquid distribution tray; three V-shaped drooping parts that extend downward and are wide at the top and narrow at the bottom are symmetrically provided on the lower circumference of each tooth-shaped liquid distribution unit. Each V-shaped drooping part is located directly below the corresponding V-shaped overflow groove.

10. The integrated high-efficiency falling film concentrator separator according to claim 9, characterized in that: The adjacent tube openings of the upper tube plate are distributed in an equilateral triangle, and every three falling film tubes correspond to one tooth-shaped liquid distribution unit. The circumference of each tooth-shaped liquid distribution unit is located above the center of the three falling film tubes, and each V-shaped drooping part of the tooth-shaped liquid distribution unit points to the center point of the tube bridge between the three falling film tubes for liquid distribution.

11. The integrated high-efficiency falling film concentrator separator according to claim 9, characterized in that: The center line of each primary liquid distribution hole on the primary liquid distribution plate is located between two adjacent tooth-shaped liquid distribution units.

12. The integrated high-efficiency falling film concentrator separator according to claim 1, characterized in that: The falling film tube is a spiral falling film tube with an oblong cross section. The two ends of the long axis of each cross section are semicircular and facing each other, and the two ends of the short axis are parallel to each other. The tube is continuously twisted into a spiral with the center line of the falling film tube as the axis.

13. The integrated high-efficiency falling film concentrator separator according to claim 12, characterized in that: In the same cross section, the major axis and minor axis of each oblong-section spiral falling film tube are parallel to each other, and the gaps between each row of oblong-section spiral falling film tubes in the minor axis direction constitute the shell-side medium channel.

14. The integrated high-efficiency falling film concentrator separator according to claim 12, characterized in that: The center distances of adjacent oblong-section spiral falling film tubes are equal to the length of the long axis, so that the adjacent oblong-section spiral falling film tubes are in tangential contact with each other through the two end points of the long axis to achieve self-support.

15. The integrated high-efficiency falling film concentrator separator according to claim 14, characterized in that: The center line of each oblong cross-section spiral falling film tube remains unchanged during the spiral process, and it makes tangential contact with the adjacent oblong cross-section spiral falling film tube six times within 360° of each pitch, and the position of the tangential contact point with the adjacent oblong cross-section spiral falling film tube changes every 60°.

16. The integrated high-efficiency falling film concentrator separator according to claim 15, characterized in that: The outer circumference of the spiral falling film tube bundle with an oblong cross section is dodecagonal and is tied with multiple straps.

17. The integrated high-efficiency falling film concentrator separator according to claim 12, characterized in that: The cross-sectional dimensions of each oblong cross-sectional spiral falling film tube are 45x25.5 mm, and the spiral pitch is 250 mm; the upper and lower ends of each oblong cross-sectional spiral falling film tube are respectively circular base tubes with an outer diameter of 38 mm.

18. The integrated high-efficiency falling film concentrator separator according to claim 1, characterized in that: A clear liquid overflow device is installed at the bottom center of the lower pipe box, and the clear liquid overflow device includes an umbrella-shaped cover and a cone bucket coaxial with the lower pipe box, a pressure-balancing elbow is provided at the cone top center of the umbrella-shaped cover, and the lower port of the umbrella-shaped cover is provided with a cylinder extending vertically downward; the cone bucket is a structure with a larger upper portion and a smaller lower portion and the upper end is located in the inner cavity of the umbrella-shaped cover, and the outer wall of the upper port of the cone bucket is connected to the inner wall of the cylinder of the umbrella-shaped cover through a plurality of symmetrically arranged ribs, the bottom of the cone bucket is supported on the bottom of the lower pipe box, and the lower end of the cone bucket is connected to an overflow clear liquid outlet extending out of the lower pipe box; the concentrated liquid enters the lower pipe box for sedimentation and separation, and the concentrated liquid containing crystal slurry particles with a higher density is discharged from the crystal slurry outlet at the bottom of the lower pipe box, and the clear liquid with a lower density floats up from the annular space between the umbrella-shaped cover cylinder and the upper end of the cone bucket and enters the cone bucket, and then is discharged from the overflow clear liquid outlet.

19. The integrated high-efficiency falling film concentrator separator according to any one of claims 1 to 18, characterized in that: A tower body bracket is welded to the upper circumferential outer wall of the tower body, and a tower top sling is fixed on the tower body bracket. The upper end of the tower top sling is bent toward the center line of the tower top and is provided with an upper pipe box lifting lug for facilitating lifting the upper pipe box; a plurality of tower body lifting lugs are also symmetrically provided on the upper circumferential outer wall of the tower body.

Images