Anti-clogging falling film distributor and falling film evaporator or absorption heat exchanger having the same

Abstract

The utility model provides a kind of anti-blocking falling film distributor and the falling film evaporator or absorption heat exchanger with the falling film distributor of this, anti-blocking falling film distributor includes the tubular body of rolling, the first opening is opened in the body, liquid preferentially can flow into the body through the first opening outside the body, further include: second opening, second opening is set on the wall surface of body, liquid can flow into the body from the body outside through second opening second opening is located above the first opening and is set with the first opening dislocation and interval certain height. By setting second opening above the first opening, to ensure that in the case where the first opening is blocked by particulate matter in liquid, liquid accumulates to the height where second opening is located on tube plate and flows into the body through second opening, and then realize that in the case where the first opening is blocked, still can pass through the body in heat exchange tube from top to bottom, uniformly and stably form liquid film, to increase heat transfer, evaporation efficiency.

Description

Technical Field

[0001] This utility model relates to the technical field of vertical in-tube falling film evaporators, and in particular to an anti-clogging falling film distributor and a falling film evaporator or absorption heat exchanger having the falling film distributor. Background Technology

[0002] The film distributor is installed above the tube sheet of a falling film evaporator or absorption heat exchanger. Its function is not only to form a thin film of liquid inside the heat exchange tubes, but also to ensure that solids pass through the film distributor.

[0003] Existing film-forming devices are equipped with multiple windows at the same height to facilitate liquid flow. However, in actual use, it has been found that these windows become clogged due to particulate matter in the liquid, preventing film formation. For example, in chlor-alkali applications, the long gas-liquid contact time leads to side reactions such as 2HCl + NaClO = NaCl + H2O + Cl2, resulting in the presence of NaCl salt in the system and causing window clogging. In the distillation of 5-hydroxymethylfurfural, the presence of powdered activated carbon in the evaporating feedstock, which adsorbs viscous substances, causes window clogging. In cyclohexanone oxime evaporation projects, the thermosensitive nature of the material means that improper temperature and pressure control can lead to coking of the oxime, causing window clogging. The evaporation of ammonium salt solutions can also cause salt crystallization, resulting in window clogging.

[0004] Therefore, a film applicator that can prevent clogging is needed to solve the above problems. Utility Model Content

[0005] The technical problem to be solved by this utility model is to overcome the defect in the existing falling film design that the liquid containing solids or particles is prone to clogging the film distributor, and to provide an anti-clogging film distributor and a falling film evaporator or absorption heat exchanger with the falling film distributor.

[0006] The present invention solves the above-mentioned technical problems through the following technical solution:

[0007] A clog-resistant falling film distribution device includes a tubular body with a first opening, through which liquid on the outside of the body can flow into the body. The device further includes:

[0008] The second opening is disposed on the wall surface of the body, through which liquid can flow from outside the body into the body. The second opening is located above the first opening and is spaced apart from the first opening.

[0009] In this design, a second opening is provided above the first opening. If the first opening is blocked by particles in the liquid, the liquid accumulates on the tube sheet to the height of the second opening and flows into the body through it. This allows for the formation of a thin film within the body even when the first opening is blocked. The second opening is spaced apart from the first opening. Compared to having the second opening integrated with the first opening, which effectively increases the extension length of the first opening, this design avoids weakening the strength of the film distributor, preventing deformation of the first opening and ensuring uniformity of the liquid film distribution.

[0010] Preferably, the second opening extends along the height direction of the body and is offset from the first opening in the circumferential direction of the body.

[0011] In this solution, the above settings can maintain the appropriate strength of the film applicator and prevent deformation of the film applicator, which would lead to a deterioration in the film application effect.

[0012] Preferably, the lower side of the second opening has a chamfer, which forms an angle of 30-80° with the height direction of the body.

[0013] In this solution, the above settings ensure that the flow rate through the membrane distributor will not change abruptly due to the surface tension of the liquid as the liquid level rises, thus preventing uneven flow rates through different membrane distributor openings.

[0014] Preferably, the distance between the second opening and the first opening along the height direction of the body is in the range of 30-60mm.

[0015] In this solution, by limiting the distance between the second opening and the first opening, the strength of the membrane applicator is ensured, thereby guaranteeing the anti-clogging effect of the membrane applicator. In addition, the distance should not be too large, which would cause the membrane applicator to be too tall, resulting in a waste of materials and space.

[0016] Preferably, the extension height of the second opening is in the range of 20-70 mm along the height direction of the body.

[0017] In this solution, the above settings ensure the reasonable design of the membrane spreader, thereby guaranteeing its anti-clogging effect. In addition, the opening width and length should not be too large, which would make the membrane spreader too big and affect the equipment height.

[0018] Preferably, the size of the second opening is larger than the size of the first opening, so that the cross-sectional area through which the liquid can flow is larger than the cross-sectional area of ​​the first opening.

[0019] In this solution, by setting up the above, in the event of blockage of the first opening, the size of the second opening is increased so that when the first opening is blocked, the liquid flows into the body through the second opening, ensuring the flow rate of fluid entering the body, while also allowing larger diameter solid particles to pass through.

[0020] Preferably, it is formed by rolling a 1.0mm stainless steel sheet with an overlap seam in the middle;

[0021] A limit block is provided in the middle of the main body to limit the installation height of the anti-clogging falling film distribution device;

[0022] The first opening and the second opening are formed by the body punching elastic first guide plate and second guide plate. The first guide plate and the second guide plate are connected to the body on one side in the horizontal direction, forming a free arm with a predetermined inclination angle to the tubular wall of the body, so that the flowing liquid forms a film in the tubular wall of the body along the predetermined angle direction of the free arm. The distance between the end of the free arm of the second opening and the tubular wall of the body is greater than the distance between the end of the free arm of the first opening and the tubular wall of the body.

[0023] The distance between the end of the free arm of the second opening and the tubular wall of the main body is 3-10 mm.

[0024] In this scheme, a limiting block is set to specify the height at which the film distributor is inserted into the heat exchange tube, so as to ensure that the amount of liquid entering the body can stably form a liquid film from top to bottom in the tube without breaking.

[0025] Preferably, the anti-clogging falling film applicator further includes a third opening through which liquid outside the body can flow into the body. The third opening is located above the second opening and is spaced apart from the second opening.

[0026] In this design, a third opening is added based on the second opening. This third opening is used for membrane application when both the first and second openings are blocked. The second and third openings work together to form a dual anti-clogging structure, improving the anti-clogging performance of the membrane applicator and adapting to extreme conditions with higher particulate matter concentrations.

[0027] Preferably, the third opening is a plurality of grooves formed downward from the upper end of the body; the depth of the downward-facing grooves ranges from 10 to 20 mm.

[0028] In this design, the aforementioned arrangement allows liquid to overflow into the body through the grooves even when both the second and first openings are blocked, thereby achieving membrane formation. By limiting the depth of the grooves, the flow rate of the solid-containing liquid into the body is ensured.

[0029] A falling film evaporator or absorption heat exchanger includes an anti-clogging falling film distributor as described above. In this embodiment, the falling film evaporator or absorption heat exchanger includes the aforementioned anti-clogging falling film distributor, which enables uniform film distribution even when the first opening is blocked, using a second or third opening, and prevents the distributor's strength from weakening, overcoming the defect that liquids containing solids or particles easily clog the distributor.

[0030] The positive and progressive effects of this invention are as follows: By providing a second opening above the first opening, even if the first opening is blocked by particles in the liquid, the liquid accumulates on the tube sheet to the height of the second opening and flows into the body through the second opening, thus enabling the formation of a thin film within the body even when the first opening is blocked. The second opening is spaced apart from the first opening, which, compared to having the second opening integrated with the first opening (effectively increasing the extension length of the first opening), prevents the strength of the film spreader from weakening, thus avoiding deformation of the first opening and affecting the uniformity of the liquid film distribution. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of the film applicator according to a preferred embodiment of the present invention.

[0032] Figure 2 This is a top view of a preferred embodiment of the film applicator of this utility model.

[0033] Explanation of reference numerals in the attached figures:

[0034] Ontology 1

[0035] First opening 11

[0036] Second opening 2

[0037] Chamfer 21

[0038] Third opening 3

[0039] Groove 31

[0040] Height direction A

[0041] Limiting block 4

[0042] First guide vane 5

[0043] Second guide vane 6 Detailed Implementation

[0044] The present invention will be described more clearly and completely below with reference to the accompanying drawings, using a preferred embodiment.

[0045] This embodiment provides an anti-clogging falling film distribution device, the specific structure of which is as follows: Figure 1 and Figure 2As shown, the anti-clogging falling film distribution device includes a tubular body 1 with a first opening 11, allowing liquid outside the body 1 to flow into the body 1 through the first opening 11. The anti-clogging falling film distribution device also includes:

[0046] The second opening 2 is disposed on the wall surface of the main body 1. Liquid can flow from the outside of the main body 1 into the main body 1 through the second opening 2. The second opening 2 is located above the first opening 11 and is spaced apart from the first opening 11.

[0047] Specifically, the body 1 is made of rolled stainless steel sheet with the upper and lower ends connected. The first opening 11 is a rectangular opening. The body 1 is set on the tube sheet (not shown in the figure) and the lower end of the body 1 is connected to the heat exchange tube (not shown in the figure). A disc distributor is set above the upper end of the body 1. Its working principle is as follows: the liquid enters the disc distributor inside the evaporator through the feed pipe. The bottom plate of the distributor has liquid drip holes. The liquid can drip along the liquid drip holes to the lower tube sheet layer and form a certain liquid level on the tube sheet. Above the top tube sheet, each heat exchange tube is designed with a film distributor, i.e., the body 1. The first opening 11 on the body 1 can ensure that the liquid forms a tangential flow in the heat exchange tube after entering the body 1, so that a stable liquid film is formed from top to bottom in the tube.

[0048] In this embodiment, based on the first opening 11, a second opening 2 is additionally provided on the body 1. Along the height direction A of the body 1, the second opening 2 is located above the first opening 11. One side of the second opening 2 is recessed towards the interior of the body 1, forming an opening similar to a half-open door structure. The opening can be a rectangular opening, and the opening is a liquid inlet. Furthermore, the second opening 2 is connected to the interior of the main body 1, allowing liquid to flow from the outside of the main body 1 into it through the second opening 2. Even if the first opening 11 is blocked by particles in the liquid, for example in chlor-alkali applications where the long gas-liquid contact time leads to the side reaction 2HCl + NaClO = NaCl + H2O + Cl2, resulting in the system containing NaCl salt, the first opening 11 will be blocked. In the distillation of 5-hydroxymethylfurfural, the evaporation feedstock contains powdered activated carbon and adsorbs viscous substances, causing the first opening 11 to become blocked. In cyclohexanone oxime evaporation projects, due to the heat sensitivity of the material, improper temperature and pressure control can lead to coking of the oxime, causing the first opening 11 to become blocked. The evaporation of ammonium salt solutions can also cause salt crystallization, leading to the first opening 11 becoming blocked. The liquid accumulates on the tube sheet to the height of the second opening 2 and flows into the interior of the main body 1 through the second opening 2, thus enabling the formation of a thin film within the main body 1 even when the first opening 11 is blocked.

[0049] In this embodiment, the second opening 2 is spaced apart from the first opening 11. Compared with the second opening 2 being integrally formed with the first opening 11, which indirectly increases the extension length of the first opening 11 along the height direction 1 of the body 1, this can prevent the strength of the film spreader from weakening, which would cause the first opening 11 of the film spreader to deform and affect the uniformity of the liquid film.

[0050] In this embodiment, the second opening 2 extends along the height direction A of the body 1 and is offset from the first opening 11 in the circumferential direction of the body 1.

[0051] Specifically, multiple second openings 2 and multiple first openings 11 are provided. This embodiment uses three first openings 11 and three second openings 2 as an example, but the number is not limited. The three first openings 11 are located on the same horizontal plane at the same height as the body 1, and the three second openings 2 are located above the first openings 11 and on the same horizontal plane at the same height. The second openings 2 are positioned between the projections of two adjacent first openings 11 along the height direction A of the body 1, so as to achieve a staggered arrangement with the first openings 11 in the circumferential direction of the body 1. This is to avoid the second opening 2 being positioned directly above the first opening 11, so as to maintain the appropriate strength of the film-laying device and prevent the film-laying device from deforming, which would lead to a deterioration in the film-laying effect.

[0052] In this embodiment, the lower side of the second opening 2 has a chamfer 21, and the chamfer 21 forms an angle of 30-80° with the height direction A of the body 1.

[0053] Specifically, the chamfer 21 is a triangular structure and is located on the lower side of the second opening 2, that is, the end of the second opening 2 facing the first opening 11. The chamfer 21 is integrally formed with the second opening 2, which is rectangular, and communicates with the second opening 2. Compared with the end of the second opening 2 being flush, the chamfer 21 can overflow liquid, so that the flow rate through the membrane device will not change abruptly due to the surface tension of the liquid as the liquid level rises, resulting in uneven flow rate through different membrane device openings.

[0054] In this embodiment, the distance between the second opening 2 and the first opening 11 along the height direction A of the body 1 ranges from 30 to 60 mm. By limiting the distance between the second opening 2 and the first opening 11, the strength of the membrane applicator is prevented from being affected by an excessively large distance, thus ensuring the anti-clogging effect of the membrane applicator. In addition, the distance should not be too large, which would cause the membrane applicator to be too tall, resulting in a waste of materials and space.

[0055] In this embodiment, the extension dimension of the second opening 2 along the height direction A of the body 1 ranges from 20 to 70 mm. By limiting the extension dimension of the second opening 2, the reasonable design of the film spreader is ensured, thereby guaranteeing the anti-clogging effect of the film spreader. In addition, the opening width and length should not be too large, which would cause the film spreader to be too large and affect the height of the equipment.

[0056] like Figure 2 As shown, in this embodiment, the size of the second opening 2 is larger than the size of the first opening 11, so that the cross-sectional area through which the liquid can flow is larger than the cross-sectional area of ​​the first opening 11.

[0057] Specifically, one side of the second opening 2 is recessed towards the interior of the body 1, forming an opening similar to a half-open door. From a top view, the structure formed by the second opening 2 and the inner wall of the body 1 is triangular. Similarly, one side of the first opening 11 is recessed towards the interior of the body 1, forming an opening similar to a half-open door. From a top view, the structure formed by the first opening 11 and the inner wall of the body 1 is also triangular. The recessed depth of one side of the first opening 11 is less than the recessed depth of one side of the second opening 2. This allows the liquid to flow into the body 1 through the second opening 2 when the first opening 11 is blocked, ensuring sufficient fluid flow. Simultaneously, the second opening 2 has a larger cross-sectional area for liquid passage, allowing larger diameter solid particles to pass through and preventing blockage.

[0058] It is understood that in this embodiment, along the height direction A of the body 1, the extension length of the first opening 11 is 20-100mm, that is, the extension length of the first opening 11 is greater than the extension length of the second opening 2. In order to ensure sufficient flow of fluid into the body 1 by increasing the recess depth of the second opening 2 and the cross-sectional area through which the fluid passes, when the extension length of the second opening 2 is less than that of the first opening 11.

[0059] In this embodiment, the body 1 is formed by rolling a 1.0mm stainless steel sheet, with an overlap seam in the middle;

[0060] A limiting block 4 is provided in the middle of the main body 1 to limit the installation height of the anti-clogging falling film distribution device; the first opening 11 and the second opening 2 are formed by punching the main body 1 with an elastic first guide plate 5 and a second guide plate 6. The first guide plate 5 and the second guide plate 6 are connected to the main body 1 on one side in the horizontal direction, forming a free arm with a predetermined inclination angle to the tubular wall of the main body 1, so that the flowing liquid forms a film in the tubular wall of the main body 1 along the predetermined angle direction of the free arm. The distance between the end of the free arm of the second opening 2 and the tubular wall of the main body 1 is greater than the distance between the end of the free arm of the first opening 11 and the tubular wall of the main body 1. The distance between the end of the free arm of the second opening 2 and the tubular wall of the main body 1 is 3-10 mm.

[0061] Specifically, the limiting block 4 can be a screw as in the prior art. The screw is used to screw onto the tubular wall of the body 1. The wall surface of the body 1 corresponding to the area where the first opening 11 is located has a threaded hole. The screw is screwed into the threaded hole, and the head size of the screw is larger than the diameter of the threaded hole, so as to form a protrusion on the outer surface of the tubular wall of the body 1. The protrusion is the shape of the screw head, which can be a hemispherical protrusion, or a cylindrical protrusion and a hexagonal prism protrusion. The protrusion is used to overlap with the tube sheet to limit the installation height of the anti-clogging falling film distributor, ensuring that the amount of liquid entering the body 1 can stably form a liquid film from top to bottom in the tube without breaking.

[0062] Furthermore, the free arm of the second opening 2, formed by the punching of the elastic second guide vane 6 by the body 1, has a certain opening angle with the inner wall of the body 1. The width distance between the end of the free arm of the second opening and the inner wall of the body 1 ranges from 3 to 10 mm. Similarly, the free arm of the first opening 11, formed by the punching of the elastic first guide vane 5 by the body 1, also has a certain opening angle with the inner wall of the body 1. The width distance between the end of the free arm of the first opening 11, which is recessed towards the interior of the body 1 to form an opening similar to a half-open door structure, and the inner wall of the body 1 ranges from 1 to 6 mm. By limiting the width distance between the end of the free arm and the inner wall of the body 1, the flow rate of fluid entering the body 1 is ensured.

[0063] In this embodiment, the anti-clogging falling film applicator also includes a third opening 3, through which liquid outside the body 1 can flow into the body 1. The third opening 3 is located above the second opening 2 and is spaced apart from the second opening 2.

[0064] Specifically, the third opening 3 is used to communicate with the interior of the body 1, and along the height direction A of the body 1, the third opening 3 is located above the second opening 2. Therefore, the third opening 3 is set on the basis of the second opening 2. The third opening 3 is used for membrane application when both the first opening 11 and the second opening 2 are blocked. The second opening 2 and the third opening 3 cooperate to form a double anti-clogging structure to improve the anti-clogging performance of the membrane applicator and adapt to extreme working conditions with more particulate matter.

[0065] In this embodiment, the third opening 3 is spaced apart from the second opening 2. Compared with the second opening 2 and the third opening 3 being integrally set, this can prevent the strength of the film spreader from weakening, which would cause the second opening 2 of the film spreader to deform and affect the uniformity of the liquid film.

[0066] In this embodiment, the third opening 3 is a plurality of grooves 31 formed downward from the upper end of the body 1.

[0067] Specifically, the third opening 3 is located at the end of the body 1 opposite to the first opening 11, and the third opening 3 has a serrated structure. The serrated structure itself has a groove 31, the depth direction of which is the height direction A of the body 1. The groove 31 penetrates the inner wall of the body 1 to achieve internal communication between the third opening 3 and the body 1. By setting the groove 31, even if both the second opening 2 and the first opening 11 are blocked, the groove 31 allows liquid to overflow into the body 1, thereby achieving membrane formation.

[0068] In other embodiments, the third opening 3 may also have a wavy structure. The difference between the wavy structure and the serrated structure lies in the shape of the groove 31. The groove 31 of the serrated structure is a "V" shaped groove, while the groove 31 of the wavy structure is an arc-shaped groove, both of which can achieve liquid overflow. Of course, in other embodiments, the third opening 3 may also have other shapes, as long as the groove 31 can meet the overflow requirements.

[0069] In this embodiment, the depth of the downward-facing groove 31 ranges from 10 to 20 mm. By limiting the depth of the groove 31, the flow rate of fluid entering the body 1 is ensured.

[0070] This embodiment also provides a falling film evaporator or absorption heat exchanger, which includes the aforementioned anti-clogging falling film distributor. It can still achieve uniform film distribution by using the second opening 2 or the third opening 3 even if the first opening 11 is blocked, and prevents the strength of the distributor from weakening, thus overcoming the defect that the distributor is easily blocked by liquid containing solids or particles.

[0071] While specific embodiments of this utility model have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this utility model is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this utility model, but all such changes and modifications fall within the scope of protection of this utility model.

Claims

1. A clogging-resistant falling film distribution device, the clogging-resistant falling film distribution device comprising a tubular body, the body having a first opening, through which liquid on the outside of the body can flow into the body, characterized in that, The anti-clogging falling film distribution device also includes: The second opening is disposed on the wall surface of the body, through which liquid can flow from outside the body into the body. The second opening is located above the first opening and is spaced apart from the first opening.

2. The anti-clogging falling film distribution device as described in claim 1, characterized in that, The second opening extends along the height direction of the body and is offset from the first opening in the circumferential direction of the body.

3. The anti-clogging falling film distribution device as described in claim 2, characterized in that, The lower side of the second opening has a chamfer, which forms an angle of 30-80° with the height direction of the body.

4. The anti-clogging falling film distribution device as described in claim 1, characterized in that, Along the height direction of the body, the distance between the second opening and the first opening ranges from 30 to 60 mm.

5. The anti-clogging falling film distribution device as described in claim 1, characterized in that, Along the height direction of the body, the extension dimension of the second opening ranges from 20 to 70 mm.

6. The anti-clogging falling film distribution device as described in claim 1, characterized in that, The size of the second opening is larger than the size of the first opening, so that the cross-sectional area through which the liquid can flow is larger than the cross-sectional area of ​​the first opening.

7. The anti-clogging falling film distribution device as described in claim 6, characterized in that, It is formed by rolling 1.0mm stainless steel sheet, with an overlap seam in the middle; A limit block is provided in the middle of the main body to limit the installation height of the anti-clogging falling film distribution device; The first opening and the second opening are formed by the body punching elastic first guide plate and second guide plate. The first guide plate and the second guide plate are connected to the body on one side in the horizontal direction, forming a free arm with a predetermined inclination angle to the tubular wall of the body, so that the flowing liquid forms a film in the tubular wall of the body along the predetermined angle direction of the free arm. The distance between the end of the free arm of the second opening and the tubular wall of the body is greater than the distance between the end of the free arm of the first opening and the tubular wall of the body. The distance between the end of the free arm of the second opening and the tubular wall of the main body is 3-10 mm.

8. The anti-clogging falling film distribution device as described in claim 1, characterized in that, The anti-clogging falling film applicator also includes a third opening through which liquid outside the main body can flow into the main body. The third opening is located above the second opening and is spaced apart from the second opening.

9. The anti-clogging falling film distribution device as described in claim 8, characterized in that, The third opening is a plurality of grooves formed downward from the upper end of the body; The depth of the downward-facing groove ranges from 10 to 20 mm.

10. A falling film evaporator or absorption heat exchanger, characterized in that, Includes the anti-clogging falling film distribution device as described in any one of claims 1 to 9.

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