Liquid film uniform distribution system of falling film evaporator

Abstract

The invention belongs to the technical field of aluminum oxide production equipment, and particularly relates to a liquid film uniform distribution system of a falling film evaporator. The liquid film uniform distribution system of the falling film evaporator comprises a body; the tube plate is arranged in the body; the heat exchange assemblies comprise a plurality of heat exchange pipes and a plurality of shielding pieces, the heat exchange pipes correspond to the shielding pieces one to one, the shielding pieces are connected with the corresponding heat exchange pipes, and liquid inlets are formed in the shielding pieces and located above the corresponding heat exchange pipes in the radial direction of the heat exchange pipes; the uniform distributor is arranged in the body and located above the heat exchange assembly; the overflow piece is arranged in the body and located above the uniform distributor, the overflow piece is provided with an overflow groove communicated with the liquid inlet pipe, and the overflow piece is annular so as to form an overflow hole communicated with the overflow groove. The liquid film uniform distribution system of the falling film evaporator can ensure the heat exchange efficiency of the falling film evaporator.

Description

Technical Field

[0001] This application belongs to the technical field of alumina production equipment, specifically relating to a liquid film uniform distribution system for a falling film evaporator. Background Technology

[0002] Falling film evaporators are the main production equipment in the evaporation process, and their water consumption and steam consumption play an important role in energy saving and consumption reduction in alumina production.

[0003] In related technologies, uneven liquid film distribution and scaling inside the heat exchange tubes in falling film evaporators lead to low heat exchange efficiency. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a liquid film uniform distribution system for a falling film evaporator, which aims to at least partially solve the technical problem of low heat exchange efficiency in falling film evaporators.

[0005] The technical solution of this invention is as follows: A liquid film uniform distribution system for a falling film evaporator includes: a main body; a tube sheet disposed within the main body; multiple rows of heat exchange assemblies, each heat exchange assembly including multiple heat exchange tubes and multiple shielding members, with each heat exchange tube corresponding to one of the shielding members, the shielding member connected to and located above the corresponding heat exchange tube, and having a liquid inlet along the radial direction of the heat exchange tube; a uniform distributor disposed within the main body and located above the heat exchange assemblies; and an overflow member disposed within the main body and located above the uniform distributor, the overflow member having an overflow groove communicating with the liquid inlet pipe, the overflow member being annular to form an overflow hole communicating with the overflow groove.

[0006] In some embodiments, the shielding member includes: a shielding portion located above the heat exchange tube; and a plurality of support portions, one end of which is connected to the shielding portion and the other end of which is connected to the heat exchange tube; wherein two adjacent support portions are spaced apart to form the liquid inlet.

[0007] In some embodiments, along the axial direction of the heat exchange tube, the projection of the shielding portion onto the body overlaps with the projection of the heat exchange tube onto the body.

[0008] In some implementations, the heights of the shielding elements in two adjacent columns of the heat exchange components are different.

[0009] In some embodiments, the distributor includes: a support base disposed within the body; a distributor obliquely disposed on the support base, wherein the distributor has a through hole coaxially disposed with the overflow hole in its middle portion, and the distributor is spaced apart from the inner wall of the body; wherein, along the axial direction of the heat exchange tube, a portion of the projection of the distributor on the body overlaps with a portion of the projection of the overflow hole on the body, and another portion of the projection of the distributor on the body partially overlaps with a portion of the projection of the overflow groove on the body.

[0010] In some embodiments, the distribution component includes: a plurality of distribution plates disposed on the support base, with adjacent distribution plates connected together.

[0011] In some embodiments, along the axial direction of the heat exchange tube, the projection of the through hole on the body overlaps with the projection of the overflow hole on the body.

[0012] In some embodiments, the angle between the distribution component and the axis of the body is 30° to 89°.

[0013] In some embodiments, the support base includes: a plurality of connecting parts, one end of which is connected to a distribution member and the other end is connected to the body; wherein, two adjacent connecting parts are spaced apart.

[0014] In some implementations, the liquid film distribution system of the falling film evaporator further includes: a first connecting pipe connected to the liquid inlet pipe; and a second connecting pipe connected to the first connecting pipe and connected to the overflow trough, wherein the second connecting pipe is arranged at an angle to the first connecting pipe.

[0015] The beneficial effects of the present invention include at least the following: Since the tube sheet is located within the main body, the multi-row heat exchange assembly includes multiple heat exchange tubes and multiple shielding components. Each heat exchange tube corresponds one-to-one with a shielding component, which is connected to and positioned above the corresponding heat exchange tube. Along the radial direction of the heat exchange tube, the shielding component has a liquid inlet. A distributor is located within the main body and above the heat exchange assembly. An overflow component is located within the main body and above the distributor. The overflow component has an overflow groove communicating with the inlet pipe. The overflow component is annular, forming an overflow hole communicating with the overflow groove. Therefore, the liquid enters the overflow groove of the overflow component through the inlet pipe. After filling the overflow groove, it overflows evenly and stably along the circumference of the overflow groove to overflow the overflow hole. During the process of the liquid overflowing from the overflow groove to the overflow hole, the flow velocity of the liquid can be effectively reduced, effectively buffering the impact force of the liquid. This weakens the turbulence effect of the liquid and provides a stable flow path for the subsequent distribution process. The pre-dispersion base ensures uniform material distribution. Under gravity, the liquid flows through the overflow hole to the distributor. When the liquid reaches the distributor, it impacts the distributor, dispersing the liquid and guiding it. The relatively uniformly distributed liquid allows the liquid to be quickly and evenly distributed on the tube sheet, improving the uniformity of the liquid distribution. The shielding component blocks the liquid above the corresponding heat exchange tubes, changing the path of the liquid and preventing it from directly entering the heat exchange tubes. This allows the liquid to accumulate on the tube sheet until the liquid level is higher than the top of the heat exchange tubes, forcing the liquid to overflow through the tube sheet and enter the heat exchange tubes through the inlet, forming a uniform wall-mounted liquid film. This achieves a true film distribution effect, completely eliminating "dry wall" and uneven liquid film phenomena, preventing scaling and blockage inside the heat exchange tubes. At the same time, the liquid film can protect the iron of the heat exchange tubes during pickling, further extending their service life and improving the heat exchange efficiency of the heat exchange tubes.

[0016] By uniformly distributing the liquid film across the entire heat exchange tube, abnormal distributions such as flow interruption, flow deviation, and full flow are eliminated, solving the problems of uneven heating and stress concentration in the heat exchange tube and avoiding the risk of acid pickling bursts. It is also adapted to the characteristics of high-alkali and high-viscosity liquids, with significant anti-scaling and anti-clogging performance, reducing the frequency of equipment maintenance. At the same time, it improves the heat exchange efficiency of the heat exchange tube, extends its service life, reduces energy consumption and equipment costs in alumina production, and the system has a compact structure, resulting in a 7.6%-22.2% increase in liquid film evaporator capacity, a 3.6%-11.1% reduction in energy consumption, and a more than 2-fold extension of heating tube life. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1This is a schematic diagram of the liquid film distribution system of a falling film evaporator according to some embodiments; Figure 2 for Figure 1 A schematic diagram of the overflow component of the liquid film distribution system in a medium-falling film evaporator; Figure 3 for Figure 1 A schematic diagram of the first structure of the shielding component in the liquid film uniform distribution system of a medium falling film evaporator; Figure 4 for Figure 1 A schematic diagram of the second structure of the shielding component in the liquid film uniform distribution system of a medium falling film evaporator; Figure 5 for Figure 1 A schematic diagram of the distributor in the liquid film distribution system of a medium falling film evaporator.

[0019] In the attached image: Body 10, feed inlet 11; Tube sheet 20; Heat exchange assembly 30, heat exchange tube 31, shielding component 32, shielding part 321, support part 322, mounting part 323, liquid inlet 33; Distributor 40, support base 41, connecting part 411, mounting part 412, distribution component 42, through hole 421, distribution plate 422, connecting component 423; Overflow component 50, overflow groove 51, overflow hole 52; Inlet pipe 60; Bracket 70; First connecting pipe 80; Second connecting pipe 90. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that all directional indications in the embodiments of the present invention are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0022] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0023] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0024] Specific technical solutions will now be described in detail with reference to the accompanying drawings, which are not necessarily drawn to scale. Similar or identical reference numerals may be used to designate the same or similar parts in different figures. The use of similar or identical reference numerals in different figures does not mean that all figures including similar or identical reference numerals constitute a single or the same embodiment. The accompanying drawings illustrate the various embodiments discussed in this application in a generalized, illustrative, and not restrictive manner.

[0025] Combination Figure 1 , Figure 2 , Figure 3 and Figure 4 The liquid film distribution system of the falling film evaporator in this embodiment includes: a body 10, a tube sheet 20, a distributor 40, an overflow member 50, and multiple rows of heat exchange assemblies 30. The tube sheet 20 is disposed within the body 10. The heat exchange assembly 30 includes multiple heat exchange tubes 31 and multiple shielding members 32, with each heat exchange tube 31 corresponding to one of the shielding members 32. The shielding member 32 is connected to the corresponding heat exchange tube 31 and is located above the corresponding heat exchange tube 31. Along the radial direction of the heat exchange tube 31, the shielding member 32 has a liquid inlet 33. The distributor 40 is disposed within the body 10 and located above the heat exchange assembly 30. The overflow member 50 is disposed within the body 10 and located above the distributor 40. The overflow member 50 has an overflow groove 51 communicating with the liquid inlet pipe 60. The overflow member 50 is annular to form an overflow hole 52 communicating with the overflow groove 51.

[0026] Since the tube sheet 20 is located inside the body 10, the multi-row heat exchange assembly 30 includes multiple heat exchange tubes 31 and multiple shielding members 32. Each heat exchange tube 31 corresponds to one shielding member 32. The shielding member 32 is connected to the corresponding heat exchange tube 31 and is located above the corresponding heat exchange tube 31, along the radial direction of the heat exchange tube 31. The shielding member 32 has a liquid inlet 33. The distributor 40 is located inside the body 10 and above the heat exchange assembly 30. The overflow member 50 is located inside the body 10 and above the distributor 40. Above, the overflow component 50 has an overflow groove 51 communicating with the inlet pipe 60. The overflow component 50 is annular to form an overflow hole 52 communicating with the overflow groove 51. Therefore, the liquid enters the overflow groove 51 of the overflow component 50 through the inlet pipe 60. After filling the overflow groove 51, it overflows and falls evenly and stably along the circumference of the overflow groove 51 to overflow into the overflow hole 52. During the process of the liquid overflowing from the overflow groove 51 to the overflow hole 52, the flow rate of the liquid can be effectively reduced, so that the impact force of the liquid can be effectively buffered, which can reduce the flow rate of the liquid. The weak turbulence effect of the liquid feed provides a stable pre-dispersion foundation for the subsequent uniform distribution process, ensuring the uniformity of the distribution. Under the action of gravity, the liquid feed flows through the overflow hole 52 to the distributor. When the liquid feed reaches the distributor, it impacts the distributor, causing the liquid feed to disperse. The distributor guides the liquid feed, resulting in a relatively uniformly distributed liquid that can be quickly and evenly distributed on the tube sheet 20, improving the uniformity of the liquid feed. The shielding element 32 blocks the liquid feed above the corresponding heat exchange tube 31, changing the path of the liquid feed and preventing it from spreading. The liquid directly enters the heat exchange tube 31, allowing the liquid to accumulate on the tube sheet 20 until the liquid level is higher than the top of the heat exchange tube 31. This forces the liquid to overflow through the tube sheet 20 and enter the heat exchange tube 31 through the inlet 33, forming a uniform liquid film that adheres to the wall. This achieves a true film-forming effect, completely eliminating the "dry wall" and uneven liquid film phenomena, and preventing scaling and blockage inside the heat exchange tube 31. At the same time, the liquid film can protect the iron of the heat exchange tube 31 during pickling, further extending its service life and improving the heat exchange efficiency of the heat exchange tube 31.

[0027] By uniformly distributing the liquid film across the entire heat exchange tube 31, abnormal distributions such as flow interruption, flow deviation, and full flow are eliminated, solving the problems of uneven heating and stress concentration in the heat exchange tube 31 and avoiding the risk of acid pickling bursts. It is also adapted to the characteristics of high-alkali and high-viscosity liquids, with significant anti-scaling and anti-clogging performance, reducing the frequency of equipment maintenance. At the same time, it improves the heat exchange efficiency of the heat exchange tube 31, extends its service life, reduces energy consumption and equipment costs in alumina production, and the system has a compact structure, resulting in a 7.6%-22.2% increase in liquid film evaporator capacity, a 3.6%-11.1% reduction in energy consumption, and a more than 2-fold extension of heating tube life.

[0028] In some embodiments, multiple rows of heat exchange components 30 are built into the body 10 and arranged in an equilateral triangle, square, or ring. The heat exchange tubes 31 are fixed to the tube sheet 20 by expansion welding, and the tube ends of the heat exchange tubes 31 extend upward and are exposed on the upper surface of the tube sheet 20 (the exposed length is not less than 10 mm).

[0029] In some embodiments, the body 10 has a feed inlet 11 and an overflow member 50 is located 100mm-300mm below the feed inlet 11.

[0030] In some embodiments, the liquid film distribution system of the falling film evaporator further includes a support 70. The support 70 is connected to the body 10 and the overflow member 50 and is used to support the overflow member 50.

[0031] In some embodiments, one end of the inlet pipe 60 is connected to the overflow tank 51, and the other end is connected to the outlet of the body 10. An inlet pump is provided on the inlet pipe 60, which provides power for the circulation of the liquid. The uniform film distribution and efficient evaporation of the liquid to be evaporated are achieved through stable fluid delivery.

[0032] In some embodiments, the heat exchange tube 31 and the tube sheet 20 are fixedly connected by expansion welding to ensure the sealing performance of the tube sheet 20 and the heat exchange tube 31 and to avoid leakage of high-alkali liquid and steam.

[0033] Combination Figure 1 , Figure 3 and Figure 4 In some embodiments, to alter the feed path, the shielding member 32 includes a shielding portion 321 and a plurality of support portions 322. The shielding portion 321 is located above the heat exchange tube 31. One end of each of the plurality of support portions 322 is connected to the shielding portion 321, and the other end is connected to the heat exchange tube 31. Adjacent support portions 322 are spaced apart to form a liquid inlet 33.

[0034] The support portion 322 supports the shielding portion 321, allowing the shielding portion 321 to block the corresponding heat exchange tube 31, thus changing the path of the liquid and preventing it from directly entering the heat exchange tube 31. This allows the liquid to accumulate on the tube sheet 20 until its level is higher than the top of the heat exchange tube 31, forcing the liquid to overflow through the tube sheet 20 and enter the heat exchange tube 31 through the inlet 33 formed by the spaced intervals between two adjacent support portions 322. This forms a uniform liquid film adhering to the wall, achieving a true film-forming effect and completely eliminating the phenomena of "dry wall" and uneven liquid film. This prevents scaling and blockage inside the heat exchange tube 31. At the same time, the liquid film can protect the iron of the heat exchange tube 31 during pickling, further extending its service life and improving the heat exchange efficiency of the heat exchange tube 31. In some embodiments, the shielding member 32 further includes a mounting portion 323. The mounting portion 323 is connected to the end of the support portion 322 away from the shielding portion 321. The mounting portion 323 is fitted with the tube opening of the heat exchange tube 31 with a clearance. The assembly clearance should be controlled within the range of 0.5mm-1mm. This clearance design can ensure the structural reliability and connection stability of the fitting between the mounting portion 323 and the heat exchange tube 31, and avoid vibration caused by excessive clearance or assembly interference caused by insufficient clearance during operation.

[0035] Combination Figure 1 In some embodiments, along the axial direction of the heat exchange tube 31, the projection of the shielding part 321 on the body 10 overlaps with the projection of the heat exchange tube 31 on the body 10, so that the shielding part 321 can completely shield the heat exchange tube 31 and prevent the liquid from directly entering the heat exchange tube 31.

[0036] If the height of the shielding element 32 of two adjacent heat exchanger units 30 is the same, it will cause impurities to accumulate, clogging the liquid inlet 33. Figure 3 and Figure 4 In some embodiments, the heights of the shielding members 32 of two adjacent heat exchanger components 30 are different, so that when impurities fall down, there are steps, allowing impurities to pass through and preventing impurities from accumulating on the top of the shielding members 32, thus avoiding blockage. This can increase the flow of liquid through the channel and effectively prevent scaling and blockage.

[0037] Combination Figure 1 and Figure 5 In some embodiments, to achieve uniform distribution of the liquid feed, the distributor 40 includes a support base 41 and a distributor 42. The support base 41 is disposed within the body 10. The distributor 42 is inclinedly disposed on the support base 41, and a through hole 421 coaxially arranged with the overflow hole 52 is formed in the middle of the distributor 42. The distributor 42 is spaced apart from the inner wall of the body 10. Along the axial direction of the heat exchange tube 31, a portion of the projection of the distributor 42 on the body 10 overlaps with a portion of the projection of the overflow hole 52 on the body 10, and another portion of the projection of the distributor 42 on the body 10 partially overlaps with a portion of the projection of the overflow trough 51 on the body 10.

[0038] The distributor 42 is supported by the support base 41 to ensure its stability within the body 10. Since the projection of the distributor 42 onto the body 10 partially overlaps with the projection of the overflow hole 52 onto the body 10 along the axial direction of the heat exchange tube 31, and another portion of the projection of the distributor 42 onto the body 10 partially overlaps with the projection of the overflow groove 51 onto the body 10, the liquid can flow to the distributor 42 when passing through the overflow hole 52. Because the distributor 42 is inclined on the support base 41, the liquid impacts the distributor 42 when it reaches it, causing the liquid to disperse. The distributor 42 guides the liquid, allowing it to fall relatively evenly through the edges and through holes 421, thus quickly and evenly distributing the liquid on the tube sheet 20 and improving the uniformity of the liquid distribution.

[0039] In some embodiments, along the axial direction of the body 10, the end of the distributor 42 away from the support base 41 is located below the overflow hole 52, so that the distributor 42 can effectively receive the overflow liquid and make the liquid quickly and evenly distributed along the slope. By enhancing the dispersion effect of the liquid, the uniformity of the liquid entering the next process is improved. Since the distributor 42 abandons the dense opening structure, it can avoid the risk of blockage caused by solid particles in the liquid from the structural level, and significantly improve the stability of equipment operation.

[0040] In some embodiments, the distributor 42 is located 100mm-200mm below the overflow member 50 to ensure the receiving and dispersing effect of the liquid.

[0041] Combination Figure 5 In some embodiments, for ease of installation and molding, the distribution member 42 includes a plurality of distribution plates 422. The plurality of distribution plates 422 are disposed on the support base 41, and adjacent distribution plates 422 are connected. For example, adjacent distribution plates 422 are connected by a connector 423.

[0042] Multiple distribution plates 422 can be installed as independent modules. Compared to a large, monolithic distribution component, each distribution plate 422 is relatively small in size and weight, making it easier for operators to move, position, and secure it, reducing labor intensity and operational difficulty during installation. Furthermore, if a distribution plate 422 experiences positional deviation during installation or requires adjustment after installation, only that single distribution plate 422 needs to be operated on without affecting the installation status of other distribution plates 422. Similarly, if a distribution plate 422 is damaged during use, only the damaged distribution plate 421 needs to be replaced, without replacing the entire distribution component 42, saving maintenance time and costs.

[0043] Combination Figure 1In some embodiments, along the axial direction of the heat exchange tube 31, the projection of the through hole 421 on the body 10 overlaps with the projection of the overflow hole 52 on the body 10, so that when the liquid reaches the distributor 42, the liquid dispersed after impacting the distributor 42 is relatively evenly sprayed through the through hole 421.

[0044] Combination Figure 1 In some embodiments, the angle between the distributor 42 and the axis of the body 10 is 30° to 89°, so that the distributor 42 is inclined and can guide the liquid, so that the liquid is relatively evenly sprinkled through the edge of the distributor 42 and the through hole 421, so that the liquid can be quickly and evenly distributed on the tube sheet 20, thereby improving the uniformity of the liquid distribution.

[0045] Combination Figure 5 In some embodiments, to support the distribution member 42, the support base 41 includes a plurality of connecting portions 411. One end of each connecting portion 411 is connected to the distribution member 42, and the other end is connected to the body 10. Adjacent connecting portions 411 are spaced apart.

[0046] Since the two adjacent connecting parts 411 are spaced apart, when the liquid flows to the edge of the distributor 42 away from the through hole 421, it can flow to the tube sheet 20 through the gap between the two adjacent connecting parts 411.

[0047] Combination Figure 1 and Figure 2 In some embodiments, to achieve liquid diversion, the liquid film distribution system of the falling film evaporator further includes: a first connecting pipe 80 and a second connecting pipe 90. The first connecting pipe 80 is connected to the liquid inlet pipe 60. The second connecting pipe 90 is connected to the first connecting pipe 80 and to the overflow tank 51, and the second connecting pipe 90 is set at an angle to the first connecting pipe 80.

[0048] The liquid in the inlet pipe 60 is transported to the overflow tank 51 through the first connecting pipe 80 and the second connecting pipe 90. The second pipe 90 changes the direction of liquid inlet from vertical to horizontal, which optimizes space, reduces the axial space occupied, and ensures uninterrupted overflow, thus ensuring stable overflow of the liquid.

[0049] When the liquid enters the overflow tank 51 through the second connecting pipe 90, the impact of the liquid is reduced, so that the liquid is evenly filled into the overflow tank 51. The amount of liquid in each area of ​​the overflow tank 51 is equal, ensuring that the liquid in each area of ​​the overflow tank 51 can overflow out of the overflow tank evenly.

[0050] In some embodiments, the included angle between the first connecting pipe 80 and the second connecting pipe 90 can be set from 45° to 135°. In this embodiment, the included angle between the first connecting pipe 80 and the second connecting pipe 90 is 90°, that is, the first connecting pipe 80 and the second connecting pipe 90 are set perpendicularly, and should not be construed as a limitation of this application.

[0051] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0052] In the description of this invention, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0053] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0054] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0055] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A liquid film uniform distribution system for a falling film evaporator, characterized by, The application relates to a falling film evaporator. The falling film evaporator comprises a body, a tube plate arranged in the body, a plurality of heat exchange assemblies arranged in the body, a distributor arranged above the heat exchange assemblies, and an overflow member arranged above the distributor. The heat exchange assembly comprises a plurality of heat exchange tubes and a plurality of shielding members. The shielding member is connected with the corresponding heat exchange tube and is arranged above the corresponding heat exchange tube along the radial direction of the heat exchange tube. The shielding member is provided with a liquid inlet. The distributor is arranged in the body and above the heat exchange assembly.

2. The liquid film uniform distribution system of falling film evaporator according to claim 1, characterized in that, The overflow member is arranged in the body and above the distributor. The overflow member is annular to form an overflow hole communicating with the overflow groove. The shielding member comprises a shielding part arranged above the heat exchange tube and a plurality of supporting parts connected with the shielding part at one end and connected with the heat exchange tube at the other end. The supporting parts are arranged at intervals to form the liquid inlet.

3. The liquid film uniform distribution system of falling film evaporator according to claim 2, characterized in that, The projection of the shielding part on the body overlaps the projection of the heat exchange tube on the body along the axial direction of the heat exchange tube.

4. The liquid film uniform distribution system of the falling film evaporator according to any one of claims 1-3, characterized in that, The heights of the shielding members of two adjacent heat exchange assemblies are different.

5. The liquid film uniform distribution system of the falling film evaporator according to any one of claims 1-3, characterized in that, The distributor comprises a supporting seat arranged in the body and a distribution member arranged on the supporting seat at an angle. The distribution member is provided with a through hole coaxially arranged with the overflow hole. The distribution member is arranged at an angle with the inner wall of the body. The projection of the distribution member on the body overlaps the projection of the overflow hole on the body along the axial direction of the heat exchange tube.

6. The liquid film uniform distribution system of the falling film evaporator according to claim 5, wherein, The projection of the distribution member on the body partially overlaps the projection of the overflow groove on the body. The distribution member comprises a plurality of distribution plates arranged on the supporting seat.

7. The liquid film uniform distribution system of the falling film evaporator according to claim 5, wherein, The through hole on the body overlaps the projection of the overflow hole on the body along the axial direction of the heat exchange tube.

8. The liquid film uniform distribution system of the falling film evaporator according to claim 5, wherein, The angle between the distribution member and the axis of the body is 30-89 degrees.

9. The liquid film uniform distribution system of the falling film evaporator according to claim 5, wherein, The supporting seat comprises a plurality of connecting parts connected with the distribution member at one end and connected with the body at the other end. The connecting parts are arranged at intervals. The falling film evaporator further comprises a first communication pipeline communicating with the liquid inlet pipeline and a second communication pipeline communicating with the first communication pipeline and the overflow groove.

10. The liquid film uniform distribution system of the falling film evaporator according to any one of claims 1-3, characterized in that, The second communication pipeline is arranged at an angle with the first communication pipeline. ​ ​

Images