Internal accessory of membrane embedded coupling rectifying tower

Abstract

The utility model discloses an internal accessory of a membrane embedded coupling rectifying tower, and belongs to the technical field of chemical engineering. The internal accessory comprises an upper screen, a shell, an internal screen and a lower screen, the internal screen is arranged in the shell, and a middle gap is defined by the internal screen and the shell; one end of the shell and one end of the inner screen are fixedly connected with the outer ring face and the inner ring face of the upper screen respectively, and the other end of the shell and the other end of the inner screen are detachably and fixedly connected with the outer ring face and the inner ring face of the lower screen respectively. The internal accessory has the advantages of being simple in structure, convenient to install, high in operation flexibility and the like. When the filler is used in cooperation with the membrane unit, the embedded membrane unit can be well protected, particles in the rectifying tower are prevented from rushing into a membrane assembly in the working process, the membrane unit is effectively protected against damage of the filler, and after the filler is filled in the middle gap, mass transfer in the rectifying process can be further improved, and the separation efficiency and effect are improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to chemical engineering technical field, concretely relates to a membrane inlay coupling rectifying column internal accessory for protecting inlay membrane unit. BACKGROUND

[0002] The distillation-membrane coupling process is divided into two processes of outer coupling and inner coupling according to the different positions of the membrane unit and the rectifying unit. The distillation-membrane outer coupling process is the most important coupling process and develops rapidly, and is divided into front tower, middle tower and rear tower coupling according to the different positions of the membrane unit. However, the outer coupling process is more similar to the combination of separation methods, and cannot fully exert the synergistic effect between membrane separation and rectification. In comparison, the membrane inlay coupling process is to embed the membrane unit in the internal of the rectifying tower, change the vapor-liquid balance in the tower through the separation effect of the membrane unit in the tower, and thus synergistically improve the rectification separation effect.

[0003] For example, Chinese patent CN 111004090 B discloses a distillation-molecular sieve membrane coupling device for separating a ternary aqueous cosolvent system. The device organically combines the distillation technology and the membrane separation technology, and sets the molecular sieve membrane assembly in a horizontal manner between at least two adjacent tower plates of the rectifying tower. The outer shell of the molecular sieve membrane assembly is a stainless steel mesh cylinder. During the component redistribution process in the gas-liquid phase of the material between the two tower plates, the molecular sieve membrane assembly dehydrates the material, breaking the original gas-liquid balance. This design not only reduces the reflux ratio of the rectifying tower, but also solves the problem of low production capacity of membrane separation, fully utilizes the respective advantages, and achieves the effect of synergistic effect.

[0004] However, in actual use, it is found that the device still has some deficiencies. Due to the large structural difference between the rectifying tower and the membrane unit, the vapor-liquid two-phase in the tower is easy to damage the membrane unit after being affected by the filler. Moreover, since the membrane unit cannot completely fill the tower section, the contact with the vapor phase is affected, so the membrane separation effect cannot be fully exerted, and the membrane area may be wasted, which limits the improvement of the rectification separation effect of the membrane inlay coupling process to some extent. Directly adding fillers in the coupling section will damage the membrane unit and cannot guarantee the improvement of the separation effect. Therefore, it is necessary to improve the coupling device, add a membrane unit protection device, and fully utilize the space in the tower to maximize the separation effect of the membrane unit. SUMMARY

[0005] The utility model discloses a purpose at solving the problem that the membrane unit cannot be contacted with the vapor-liquid phase in the tower and the membrane unit is easy to be damaged in the prior art, and provides a membrane embedded coupling rectifying tower internal accessory, which can protect the membrane unit and promote the contact between the vapor phase in the tower and the membrane unit, thereby fully exerting the separation function of the membrane unit, improving the separation efficiency of the membrane embedded coupling rectifying device, meeting the actual application requirements, and having the advantages of simple structure, convenient installation, high operation flexibility and the like.

[0006] In order to realize the above technical purpose, the utility model is through following technical scheme to realize: membrane embedded coupling rectifying tower internal accessory, including upper screen, shell, internal screen and lower screen, the internal screen is located in the shell, and the internal screen and the shell form annular middle gap, and one end of the shell and the internal screen is fixed with the outer ring surface and the inner ring surface of the upper screen respectively and is detachably fixed with the outer ring surface and the inner ring surface of the lower screen respectively.

[0007] Further, the internal screen and the shell are both cylindrical and coaxially arranged, and the external surface of the internal screen is uniformly distributed with a plurality of screen holes.

[0008] Further, the external surface of the shell is a complete surface without screen holes.

[0009] Alternatively, the external surface of the shell is uniformly distributed with a plurality of screen holes.

[0010] Further, the upper screen and the lower screen are both annular, and the annular planes of the upper screen and the lower screen are uniformly distributed with a plurality of screen holes.

[0011] Further, the inner diameter of the internal screen is greater than the outer diameter of the embedded membrane unit.

[0012] Further, the internal accessory is directly connected to the outer periphery of the membrane unit or fixedly connected to the top vacuum extraction end of the membrane unit.

[0013] The utility model discloses the beneficial effects are:

[0014] The membrane embedded coupling rectifying tower internal accessory disclosed in the application is arranged at the outer periphery of the membrane unit, and the internal screen can well protect the embedded membrane unit, avoid the particles in the rectifying tower from rushing into the membrane assembly during the working process, effectively protect the membrane unit from being damaged by the filler, and further improve the mass transfer in the rectifying process after filling the filler in the middle gap, promote the contact between the membrane unit and the vapor phase in the tower, strengthen the in-situ dehydration of the membrane unit in the tower, and improve the separation efficiency and effect.

[0015] The internal accessory disclosed in the application has a simple structure and is matched with the membrane unit and the rectifying tower structure, which is beneficial to the installation of the internal accessory in the tower.

[0016] The lower screen of the internal accessory disclosed in the application is detachably fixed at one end of the shell and the internal screen, and the design facilitates filling of the filler into the middle gap;

[0017] The internal accessory disclosed in the application is integrally arranged outside the membrane unit in a detachable form, has strong operation flexibility, is convenient to adjust in the face of different application scenarios, and enhances the applicability of the accessory. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 A three-dimensional isometric view of the internal accessory of the membrane-embedded coupled rectifying column;

[0019] Figure 2 A top view of the internal accessory of the membrane-embedded coupled rectifying column is shown in the figure. Figure 1

[0020] Figure 3 A front view of the internal accessory of the membrane-embedded coupled rectifying column after being sleeved outside the membrane unit is shown in the figure.

[0021] In the figure, 1 is an upper screen, 2 is a shell, 3 is an internal screen, 4 is a middle gap, 5 is a lower screen, and 6 is an embedded membrane unit. DETAILED DESCRIPTION

[0022] The following examples further illustrate the content of the present application, but should not be understood as limiting the present application. Modifications and replacements of the method, steps or conditions of the present application, without departing from the essence of the present application, all belong to the protection scope of the present application.

[0023] In the description of the present application, it should be understood that the terms "mounting", "connection" and "connection" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integral connection; it can be direct connection, or connection through intermediate medium, or connection between two elements. For ordinary skilled in the art, the meaning of the above terms in the present application can be understood according to the specific circumstances. In addition, the terms "first" and "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance. In addition, in the description process of the embodiments of the present application, the device position relationship of "up", "down", "front", "back", "left", "right" and the like in all the figures is based on the standard of the drawings.

[0024] ​In order to solve the problems of the membrane unit in the existing distillation-molecular sieve membrane coupling device being difficult to maximize the separation effect and membrane damage due to lack of protection, the utility model provides an internal accessory of a membrane embedded coupling distillation tower, which is composed of an upper screen 1, an outer shell 2, an internal screen 3 and a lower screen 5. The internal screen 3 and the outer shell 2 are both cylindrical. The internal screen 3 is arranged inside the outer shell 2 and the two are coaxially arranged. Several sieve holes are evenly distributed on the outer surface of the internal screen 3. The internal screen 3 and the outer shell 2 enclose an annular middle gap 4, and the middle gap 4 is used to fill the filler. Figure 1 The outer surface of the shell 2 shown in the figure is a complete surface without sieve holes. In actual use, the outer surface of the shell 2 can also be selected to have a sieve structure with uniform sieve holes according to actual needs, that is, the surface of the shell 2 can also be evenly provided with several sieve holes.

[0025] The upper screen 1 and the lower screen 5 are both annular, with several sieve holes evenly distributed on their annular surfaces. One end of the outer shell 2 and the inner screen 3 are fixedly connected to the outer and inner annular surfaces of the upper screen 1, respectively. The other ends of the outer shell 2 and the inner screen 3 are removably fixedly connected to the outer and inner annular surfaces of the lower screen 5, respectively. That is, the lower screen 5 can be removed from one end of the outer shell 2 and the inner screen 3 to facilitate the filling of the intermediate gap 4. The inner diameter of the inner screen 3 is larger than the outer diameter of the embedded membrane unit 6, which facilitates the integral fixing of the internal accessory to the outer periphery of the embedded membrane unit 6. The length of the internal accessory is adapted to the length of the embedded membrane unit 6 to provide all-round protection for the membrane unit.

[0026] The specific usage of the device is as follows:

[0027] like Figure 3 As shown, the membrane is embedded in the coupling distillation tower and the internal accessories are sleeved on the outer periphery of the embedded membrane unit 6. In order to improve the stability of the sleeve connection, the upper screen 1 can be fixedly connected to the top vacuum end of the embedded membrane unit 6 (molecular sieve membrane assembly), and the lower screen 5 is removed from the end of the shell 2. After the filler is filled into the middle gap 4, the lower screen 5 is fixed to the end of the shell 2. Adding filler in the middle gap 4 helps to improve mass transfer during the distillation process and improve separation efficiency. With the protection of the accessories provided on the outside of the membrane unit, particles in the distillation tower can be prevented from rushing into the membrane assembly during operation, thereby avoiding membrane damage and effectively protecting the membrane unit from damage by the filler.

[0028] Application Examples

[0029] This application example is based on the use of internal accessories of a membrane-coupled distillation column to separate an ethanol / water system using a distillation-molecular sieve membrane coupling device. For example, a feed mass of 4.5 kg, with a feed composition of 90 wt.% ethanol and 10 wt.% water, is used. The membrane area is 0.081 m 2The experimental results are shown in Table 1. Analysis of the experimental results shows that the quality of the distillate does not change significantly after the installation of the tower internal accessories, indicating that the presence of the accessories has limited effect on the vapor-liquid phase in the tower, and the rectifying column can still work stably. The increase in ethanol content at the top of the tower indicates that the accessories promote the contact between the vapor phase in the tower and the membrane unit. As can be seen from the flow rate on the permeation side, the in-situ dehydration effect of the membrane unit in the tower is enhanced, and the mass on the permeation side increases. Therefore, the ethanol content in the vapor phase after passing through the membrane unit increases, and the effect of rectification separation is improved.

[0030] Table 1 Comparison of experimental results of embedded coupling rectification

[0031]

[0032] The above results show that it is feasible to use the membrane-embedded coupling rectification tower internal accessory for the separation of ethanol / water. The tower internal accessory plays a role in protecting the embedded membrane unit, promotes the contact between the membrane unit and the vapor phase in the tower, strengthens the in-situ dehydration effect of the membrane unit in the tower, solves the problem caused by the difference between the membrane unit and the rectifying column structure, and thus further improves the effect of rectification separation.

Claims

1. Membrane embedded coupling distillation column internal accessories, characterized in that, It includes an upper screen, an outer shell, an inner screen and a lower screen. The inner screen is arranged inside the outer shell. The inner screen and the outer shell form an intermediate gap. One end of the outer shell and the inner screen is fixedly connected to the upper screen, and the other end is detachably fixedly connected to the lower screen.

2. The membrane embedded coupling distillation column internal accessory according to claim 1, characterized in that: The inner screen and the outer shell are both cylindrical and coaxially arranged, and a plurality of screen holes are evenly distributed on the outer surface of the inner screen.

3. The membrane embedded coupling distillation column internal accessory according to claim 1, characterized in that: The outer surface of the shell is a complete surface without sieve holes.

4. The membrane embedded coupling distillation column internal accessory according to claim 1, characterized in that: A plurality of sieve holes are evenly distributed on the outer surface of the shell.

5. The membrane embedded coupling distillation column internal accessory according to claim 1, characterized in that: The upper screen and the lower screen are both annular. One end of the outer shell and the inner screen are fixedly connected to the outer ring surface and the inner ring surface of the upper screen respectively, and the other end is detachably fixed to the outer ring surface and the inner ring surface of the lower screen respectively. Several sieve holes are evenly distributed on the annular planes of the upper screen and the lower screen.

6. The membrane embedded coupling distillation column internal accessory according to claim 1, characterized in that: The inner diameter of the inner screen is larger than the outer diameter of the embedded membrane unit.

7. The membrane embedded coupling distillation column internal accessory according to claim 1, characterized in that: The internal accessories are directly sleeved and connected to the outer periphery of the membrane unit.

8. The membrane embedded coupling distillation column internal accessory according to claim 1, characterized in that: The upper screen is fixedly connected to the vacuum end at the top of the membrane unit.

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