Falling film evaporator for 1, 4-butylene glycol rectifying tower
By setting up a liquid distribution shell and a limiting rod in the falling film evaporator, and by using stirring blades and an expansion head, the problem of uneven liquid distribution is solved, and uniform liquid distribution is achieved. This solves the problem of uniform liquid distribution, avoids scaling on the inner wall of the heating tube, and improves heat transfer efficiency.
Patent Information
- Application Number
- CN202423160105.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-20
- Publication Date
- 2025-12-02
- Estimated Expiration
- 2034-12-20
AI Technical Summary
Uneven distribution of liquid in existing falling film evaporators leads to insufficient or absent liquid on the inner wall of the heating tubes, resulting in evaporation and scaling, which affects heat transfer efficiency.
A liquid distribution shell and a limiting rod are set in the falling film evaporator. Combined with a stirring paddle and an expansion head, the liquid is evenly distributed by the stirring blades, and the limiting rod and expansion head are used to force the flow so that the liquid flows tightly against the inner wall of the heat exchange tube.
This achieves uniform distribution of the liquid material, avoids scaling on the inner wall of the heating tube, and improves heat transfer efficiency.
Smart Images
Figure CN223615393U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of basic chemical raw material manufacturing, and in particular to a falling film evaporator for a 1,4-butenediol distillation column. Background Technology
[0002] 1,4-Butenediol is a colorless liquid at room temperature and pressure, readily soluble in water and most organic solvents. It is used as a plasticizer for alkyd resins, a crosslinking agent for synthetic resins, and a bactericide. It can also be used in the production of nylon, pharmaceuticals, and other products. In the production stage, 1,4-Butenediol requires distillation and fractionation through a distillation column and a falling film evaporator to obtain a concentrated solution. The falling film evaporation principle involves adding the feed liquid from the upper tube box of the heating chamber of the falling film evaporator. Through a liquid distribution and film-forming device, it is evenly distributed into each heat exchange tube. Under the influence of gravity, vacuum induction, and airflow, it forms a uniform film that flows downwards. During this flow, the liquid is heated and vaporized by the shell-side heating medium. The resulting vapor and liquid phase enter the separation chamber of the evaporator together. After thorough separation, the vapor enters the condenser for condensation (single-effect operation) or enters the next effect evaporator as a heating medium, thus achieving multi-effect operation. The liquid phase is discharged from the separation chamber.
[0003] In the existing technology, the liquid distributor is a key component of the falling film evaporator. Due to the drawback of uneven distribution of liquid in the current falling film evaporator, when the liquid cannot evenly wet the inner surface of all heating tubes, the surface with insufficient liquid may dry out and form scale. The scaled surface, in turn, hinders the flow of the liquid film, thereby further deteriorating the heat transfer conditions in the adjacent area.
[0004] To address this issue, a falling film evaporator for 1,4-butenediol distillation column is proposed, which has the advantages of improving the uniformity of feed distribution and preventing scaling, thereby solving the problems mentioned in the background technology. Utility Model Content
[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a falling film evaporator for a 1,4-butenediol distillation column.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: a falling film evaporator for a 1,4-butenediol distillation column, comprising a falling film evaporator body, a feed inlet provided on the left side wall of the falling film evaporator body, and a circulation pipe connected to the port of the feed inlet by a flange, a circulation pump installed on the surface of the circulation pipe, and the end of the circulation pipe away from the falling film evaporator body connected to the distillation column, a steam inlet connected to the falling film evaporator body being provided below the feed inlet, and a feed outlet provided on the right side wall of the falling film evaporator body, the port of the feed outlet being connected to the lower part of the distillation column, a heat exchange tube assembly internally installed in the falling film evaporator body, and an upper baffle plate installed on the top of the heat exchange tube assembly. Furthermore, a lower baffle is installed at the bottom of the heat exchange tube assembly, and several liquid inlet holes are opened on the surface of the upper baffle. Each liquid inlet hole is welded with a limit rod. An extension head is welded to the bottom of the limit rod, and a slope surface is provided at the connection between the extension head and the limit rod. The extension head extends into the interior of one of the tube shells of the heat exchange tube assembly. A liquid distribution shell is fixed on the upper inner side of the falling film evaporator body, and the bottom of the liquid distribution shell is in contact with the upper baffle. Several diversion ports are opened on the bottom surface of the liquid distribution shell corresponding to the liquid inlet holes. A motor is fixedly installed on the top of the falling film evaporator body, and an agitator is fixed through the motor output end of the falling film evaporator body. The agitator blades extend into the inner side of the liquid distribution shell.
[0007] As a further description of the above technical solution: the stirring paddle is composed of a shaft and several stirring blades arranged around its bottom, and the surface of the stirring blades of the stirring paddle is provided with several round holes.
[0008] As a further description of the above technical solution: two connecting posts are welded to the end of the limiting rod away from the extension head, and both connecting posts are welded to the inner wall of the liquid inlet hole, and an annular gap is formed between the liquid inlet hole and the limiting rod.
[0009] As a further description of the above technical solution: the plurality of liquid inlet holes of the upper baffle correspond one-to-one with the plurality of diversion ports of the liquid distribution shell, and the plurality of liquid inlet holes are respectively connected to the upper ends of the plurality of tube shells of the heat exchange tube assembly.
[0010] As a further description of the above technical solution: the surface of the lower baffle is provided with a number of through holes, and the number of through holes are respectively connected to the lower ends of a number of tube shells of the heat exchange tube assembly.
[0011] As a further description of the above technical solution: the side of the liquid distribution shell is in close contact with the falling film evaporator body, and the top surface of the liquid distribution shell is provided with an opening.
[0012] This utility model has the following beneficial effects:
[0013] In this invention, a liquid distribution shell and an upper baffle with limiting columns are installed above the heat exchange tube assembly of the falling film evaporator body. As the circulating pipe injects the liquid from the distillation column into the liquid inlet, the stirring paddle installed at the motor output end agitates the liquid entering the liquid distribution shell through several stirring blades, so that the liquid flows evenly into several branch ports of the liquid distribution shell. Since the surface of the upper baffle has several liquid inlet holes connected to each tube shell of the heat exchange tube assembly, and each liquid inlet hole is welded with a limiting rod with an extension head, the liquid passing through the branch port enters the annular gap between the liquid inlet hole and the limiting rod. Then, the extension head of the limiting column and the slope between the two forcefully guide the liquid, so that the liquid flows down close to the inner wall of the heat exchange tube assembly tube shell. This increases the uniformity of liquid distribution and avoids the situation where the liquid dries up and scales due to insufficient liquid on the inner wall of the tube shell. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the overall structure of the falling film evaporator for the 1,4-butenediol distillation column of this utility model;
[0015] Figure 2 This is a schematic diagram of the internal structure of a falling film evaporator;
[0016] Figure 3 This is a schematic diagram of the upper baffle.
[0017] Figure 4 This is a schematic diagram of the limit rod.
[0018] Legend:
[0019] 1. Falling film evaporator body; 2. Distillation column; 3. Circulation pipe; 4. Circulation pump; 5. Motor; 6. Feed inlet; 7. Steam inlet; 8. Feed outlet; 9. Heat exchanger tube assembly; 10. Lower baffle; 11. Upper baffle; 12. Feed distribution shell; 13. Stirring paddle; 14. Diverter port; 15. Liquid inlet hole; 16. Limiting rod; 17. Extension head; 18. Sloping surface; 19. Connecting column. Detailed Implementation
[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0021] According to an embodiment of the present invention, a falling film evaporator for a 1,4-butenediol distillation column is provided.
[0022] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments, such as... Figure 1-4 As shown, the falling film evaporator for the 1,4-butenediol distillation column 2 according to an embodiment of the present invention includes a falling film evaporator body 1. A feed inlet 6 is provided on the left side wall of the falling film evaporator body 1, and a circulation pipe 3 is flanged at the port of the feed inlet 6. A circulation pump 4 is installed on the surface of the circulation pipe 3, and the end of the circulation pipe 3 away from the falling film evaporator body 1 is connected to the distillation column 2. A steam inlet 7, connected to the falling film evaporator body 1, is provided below the feed inlet 6. A feed outlet is provided on the right side wall of the falling film evaporator body 1. The feed outlet 8 is connected to the lower part of the distillation column 2. The falling film evaporator body 1 has a heat exchange tube assembly 9 installed inside. The top of the heat exchange tube assembly 9 is equipped with an upper baffle 11, and the bottom of the heat exchange tube assembly 9 is equipped with a lower baffle 10. The surface of the upper baffle 11 has several liquid inlet holes 15, and each liquid inlet hole 15 is welded with a limit rod 16. The bottom of the limit rod 16 is welded with an extension head 17, and a slope surface 18 is provided at the connection between the extension head 17 and the limit rod 16. The extension head 17 extends to the heat exchange tube assembly. Inside one of the tube shells of 9, a liquid distribution shell 12 is fixed to the upper inner side of the falling film evaporator body 1, and the bottom of the liquid distribution shell 12 is in contact with the upper baffle 11. Several diversion ports 14 are opened on the bottom surface of the liquid distribution shell 12 corresponding to the liquid inlet 15. A motor 5 is fixedly installed on the top of the falling film evaporator body 1, and a stirring paddle 13 is fixed through the output end of the motor 5 through the falling film evaporator body 1. The stirring blades of the stirring paddle 13 extend to the inner side of the liquid distribution shell 12. The falling film evaporator body 1 of this device is mainly used for the fractional concentration of 1,4-butenediol, and can also be used for the fractional concentration of other liquids. The contents of the falling film evaporator body 1 not described in detail in this specification are known prior art to those skilled in the art. For the circulating pump 4 and the motor 5, the control method of this utility model is to control them by manually starting and stopping the switch. The wiring diagram of the power components and the power supply are common knowledge in the art. Since this utility model is mainly used to protect mechanical devices, the control method and wiring arrangement will not be explained in detail in this utility model.
[0023] In one embodiment, the stirring paddle 13 is composed of a shaft and several stirring blades arranged around its bottom. The stirring blades of the stirring paddle 13 have several round holes on their surface. The stirring paddle 13 facilitates the stirring of the liquid, making the liquid evenly distributed in the liquid distribution shell 12. The round holes reduce the resistance of the stirring blades.
[0024] In one embodiment, two connecting posts 19 are welded to the end of the limiting rod 16 away from the extension head 17, and both connecting posts 19 are welded to the inner wall of the liquid inlet 15. An annular gap is formed between the liquid inlet 15 and the limiting rod 16. The setting of the annular gap facilitates the "falling film" of the liquid.
[0025] In one embodiment, a plurality of liquid inlet holes 15 of the upper baffle 11 correspond one-to-one with a plurality of diversion ports 14 of the liquid distribution shell 12. The plurality of liquid inlet holes 15 are respectively connected to the upper ends of a plurality of tube shells of the heat exchange tube assembly 9. By setting the upper baffle 11, the liquid in the liquid distribution shell 12 can be easily diverted and poured into a plurality of tube shells of the heat exchange tube assembly 9, and forced to flow down along the inner wall of the tube shell by the limiting rod 16. The diameter of the circular expansion head 17 is smaller than the inner diameter of the tube shell of the heat exchange tube assembly 9, which facilitates the downward flow of the liquid.
[0026] In one embodiment, the surface of the lower baffle 10 is provided with a plurality of through holes, and the plurality of through holes are respectively connected to the lower ends of a plurality of tube shells of the heat exchange tube assembly 9. The lower baffle 10 provides support for the heat exchange tube assembly 9 on the one hand, and facilitates the discharge of liquid on the other hand.
[0027] In one embodiment, the side of the liquid distribution shell 12 is in close contact with the falling film evaporator body 1, and the top surface of the liquid distribution shell 12 is provided with an opening. Through the liquid distribution shell 12, the liquid entering the falling film evaporator body 1 can be temporarily stored in the liquid distribution shell 12, which facilitates the uniform distribution of the liquid.
[0028] Working principle:
[0029] In operation, first, the circulation pump 4 on the surface of the circulation pipe 3 is started to pump the feed liquid (1,4-butenediol solution) into the falling film evaporator body 1 through the circulation pump 4. Then, heating steam is introduced into the falling film evaporator body 1 through the steam inlet 7. As the circulation pipe 3 injects the feed liquid from the distillation column 2 into the feed liquid inlet 6, the stirring paddle 13 installed at the output end of the motor 5 agitates the feed liquid entering the feed liquid distribution shell 12 with several stirring blades, so that the feed liquid flows evenly into several branch ports 14 of the feed liquid distribution shell 12. Since the surface of the upper baffle 11 has several openings for each tube of the heat exchange tube group 9, The liquid inlet 15 is connected to the shell, and a limiting rod 16 with an extension head 17 is welded inside each liquid inlet 15. The liquid entering through the diversion port 14 enters the annular gap between the liquid inlet 15 and the limiting rod 16. The extension head 17 of the limiting rod and the inclined surface 18 between them force the liquid to flow, so that the liquid can flow down close to the inner wall of the heat exchange tube group 9, achieving uniform distribution of the liquid and avoiding the situation where the liquid dries up and forms scale due to insufficient or no liquid on the inner wall of the tube. During this process, the liquid flowing to the liquid outlet 8 is returned to the distillation column 2 to realize the circulation of the liquid.
[0030] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. 1, A falling film evaporator for a 4-butenediol distillation column, comprising a falling film evaporator body (1), characterized in that: A liquid inlet (6) is provided on the left side wall of the falling film evaporator body (1), and a circulation pipe (3) is connected to the port of the liquid inlet (6) by a flange. A circulation pump (4) is installed on the surface of the circulation pipe (3), and the end of the circulation pipe (3) away from the falling film evaporator body (1) is connected to a distillation column (2). A steam inlet (7) connected to the falling film evaporator body (1) is provided below the liquid inlet (6). A liquid outlet (8) is provided on the right side wall of the falling film evaporator body (1), and the port of the liquid outlet (8) is connected to the lower part of the distillation column (2). A heat exchange tube assembly (9) is installed inside the falling film evaporator body (1), and an upper baffle (11) is installed on the top of the heat exchange tube assembly (9), and a lower baffle (10) is installed on the bottom of the heat exchange tube assembly (9). Several liquid inlet holes (11) are opened on the surface of the upper baffle (11). 5), and each liquid inlet hole (15) is welded with a limiting rod (16), the bottom of the limiting rod (16) is welded with an extension head (17), and the connection between the extension head (17) and the limiting rod (16) is provided with a slope surface (18), and the extension head (17) extends into the interior of one of the tube shells of the heat exchange tube group (9). The upper inner side of the falling film evaporator body (1) is fixed with a liquid distribution shell (12), and the bottom of the liquid distribution shell (12) is in contact with the upper baffle (11), and the bottom surface of the liquid distribution shell (12) is provided with several diversion ports (14) corresponding to the liquid inlet hole (15). The top of the falling film evaporator body (1) is fixedly installed with a motor (5), and the output end of the motor (5) is fixedly installed with a stirring paddle (13) through the falling film evaporator body (1), and the stirring blades of the stirring paddle (13) extend into the inner side of the liquid distribution shell (12).
2. The falling film evaporator for the 1,4-butenediol distillation column according to claim 1, characterized in that: The stirring paddle (13) is composed of a shaft and several stirring blades arranged around its bottom, and the stirring blades of the stirring paddle (13) have several round holes on their surface.
3. The falling film evaporator for the 1,4-butenediol distillation column according to claim 1, characterized in that: Two connecting posts (19) are welded to the end of the limiting rod (16) away from the extension head (17), and both connecting posts (19) are welded to the inner wall of the liquid inlet (15). An annular gap is formed between the liquid inlet (15) and the limiting rod (16).
4. The falling film evaporator for a 1,4-butenediol distillation column according to claim 1, characterized in that: The upper baffle (11) has several liquid inlet holes (15) that correspond one-to-one with several diversion ports (14) of the liquid distribution shell (12), and the several liquid inlet holes (15) are respectively connected to the upper ends of several tube shells of the heat exchange tube group (9).
5. The falling film evaporator for a 1,4-butenediol distillation column according to claim 1, characterized in that: The surface of the lower baffle (10) is provided with several through holes, and the several through holes are respectively connected to the lower ends of several tube shells of the heat exchange tube group (9).
6. The falling film evaporator for a 1,4-butenediol distillation column according to claim 1, characterized in that: The side of the liquid distribution shell (12) is in close contact with the falling film evaporator body (1), and the top surface of the liquid distribution shell (12) is open.