Purification and recovery device of organic solvent, method and application thereof

Abstract

The present application relates to the field of environmental protection and energy saving, more specifically, it relates to a kind of organic solvent purification recovery device and method and application, device includes along front and rear procedure sequentially connected raw liquid tank, light component separator, heavy component separator, first relay tank, front section dehydration membrane device, rear section dehydration membrane device, decoloring device, second relay tank, depth purification device and finished product tank, first filter is provided between raw liquid tank and light component separator, light component separator is connected with first condenser, second condenser is arranged between heavy component separator and first relay tank, preheater is arranged between first relay tank and front section dehydration membrane device, third condenser is arranged between decoloring device and second relay tank, second filter is arranged between depth purification device and finished product tank, the present application effectively combines and utilizes distillation method and dehydration membrane method, thereby in the case where cost is reduced and energy consumption is reduced, good purification recovery effect is maintained.

Description

Technical Field

[0001] This invention relates to the field of environmental protection and energy conservation technology, and in particular to an organic solvent purification and recovery device, method and application. Background Technology

[0002] Organic solvents play a crucial role in semiconductor manufacturing processes. Various organic solvents are used to clean semiconductor device surfaces, remove residual photoresist or thin films, and serve as carrier gases in chemical vapor deposition (CVD) and physical chemical vapor deposition (PECVD) processes. In particular, organic solvents used in semiconductors such as IPA (isopropanol), Thinner-1 (propylene glycol methyl ether acetate + isopropanol methyl ether), NMP (N-methylpyrrolidone), EKC270T (developer), Thinner-2 (propylene glycol methyl ether acetate + isopropanol methyl ether), and Develop-2 (cyclopentanone), as well as NMP used in lithium-ion batteries, are used in large quantities. With the rapid development of the semiconductor industry and new energy sources in recent years, the use of organic solvents has increased significantly. Therefore, reducing the cost of using organic solvents such as those mentioned above to improve product competitiveness has become an urgent problem for enterprises. One approach is to purify and recycle the waste liquid generated during the production process.

[0003] Currently, methods for purifying organic solvents include distillation and dehydration membrane methods. Distillation is relatively simple, generally requiring heating the mixture to its boiling point and then collecting the distillate. It is commonly used in large-scale industrial production. However, the construction and operation costs of distillation columns are high, and energy consumption is also significant, resulting in a high-cost disadvantage. Dehydration membrane methods utilize semi-permeable membrane technology to separate water and impurities. For example, the mixture is fed into a dehydration membrane device, allowing water molecules to pass through the membrane pores, thus dehydrating the organic solvent for purification. Compared to distillation, dehydration membrane methods can be performed at lower temperatures and pressures, reducing energy consumption. However, impurities and particles in the organic solvent can clog the membrane pores, reducing separation efficiency or causing membrane damage. Therefore, membrane fouling and lifespan are critical issues.

[0004] Based on this, the inventors proposed an organic solvent purification and recovery device, method and application, which effectively combines distillation and dehydration membrane methods to maintain good purification and recovery effect while reducing costs and energy consumption. Summary of the Invention

[0005] In order to effectively combine distillation and dehydration membrane methods to maintain good purification and recovery effects while reducing costs and energy consumption, this application provides an organic solvent purification and recovery device, method and application.

[0006] In a first aspect, the present invention provides an apparatus for purifying and recovering organic solvents, employing the following technical solution: An organic solvent purification and recovery device includes a raw liquid tank, a light component separator, a heavy component separator, a first relay tank, a front-end dehydration membrane device, a rear-end dehydration membrane device, a decolorization device, a second relay tank, a deep purification device, and a finished product tank, connected sequentially along the preceding and following processes. A first filter is provided between the raw liquid tank and the light component separator. The light component separator is connected to a first condenser. A second condenser is provided between the heavy component separator and the first relay tank. A preheater is provided between the first relay tank and the front-end dehydration membrane device. A third condenser is provided between the decolorization device and the second relay tank. A second filter is provided between the deep purification device and the finished product tank.

[0007] Preferably, a first return pipeline is connected between the front-end dehydration membrane device and the first relay tank.

[0008] Preferably, a second return pipeline is connected between the downstream dehydration membrane device and the second relay tank.

[0009] Preferably, the pipeline on the light component separator with the first condenser is the first condensation pipeline, the pipeline between the heavy component separator and the first relay tank with the second condenser is the second condensation pipeline, the path between the first relay tank and the front dehydration membrane device with the preheater is the preheating pipeline, the first condensation pipeline and the preheating pipeline intersect at a position in front of the first condenser and the preheater, and the second condensation pipeline and the preheating pipeline intersect at a position in front of the second condenser and the preheater.

[0010] Preferably, the first condensing pipe includes a first spiral section, and the second condensing pipe includes a second spiral section. Both the first spiral section and the second spiral section are wound around the preheating pipe. The axis of the flow path of the light component in the first spiral section and the axis of the flow path of the heavy component in the second spiral section are opposite to the axis of the flow path of the organic solvent in the preheating pipe. Both the first spiral section and the second spiral section are in contact with the preheating pipe.

[0011] Preferably, the first helical tube segment is positioned in front of the second helical tube segment.

[0012] Preferably, the preheating pipeline includes a low-temperature junction section and a high-temperature junction section. The preheating pipeline uses the low-temperature junction section to connect with the first spiral section, and the preheating pipeline uses the high-temperature junction section to connect with the second spiral section. The inner diameter of the high-temperature junction section is larger than the inner diameter of the low-temperature junction section, and a spiral baffle is provided along the axis on the inner wall of the high-temperature junction section.

[0013] Preferably, the inner diameter of the second spiral tube segment is larger than the inner diameter of the first spiral tube segment.

[0014] Secondly, the present invention provides a method for purifying and recovering organic solvents, employing the following technical solution: A method for purifying and recovering an organic solvent includes the following steps: S1: The raw liquid in the raw liquid tank is filtered using the first filter, and the filtered raw liquid enters the next process. S2: The light component separator and the heavy component separator are used sequentially to separate the light components and heavy components of the raw liquid, and the heavy component organic solvent enters the next process. S3: The organic solvent is dehydrated sequentially using the front-end dehydration membrane device and the rear-end dehydration membrane device; S4: The decolorizing device is used to remove colored substances from the organic solvent; S5: Remove metal ions from the organic solvent using the aforementioned deep purification device; S6: The organic solvent is filtered using the second filter, and the filtered finished liquid is loaded into the finished product tank; In S3, if the dehydration effect does not meet expectations, the organic solvent is returned to the first relay tank for further dehydration; in S6, if the effect of the finished liquid does not meet expectations, the finished liquid is returned to the first relay tank for further purification.

[0015] In a third aspect, the present invention provides applications of the above-described apparatus in the semiconductor field.

[0016] The beneficial effects of this invention are as follows: 1. The light component separator and heavy component separator use distillation to pre-purify the organic solvent, while the front-end dehydration membrane device and the back-end dehydration membrane device use dehydration membrane method for further purification. Since the initial purification has been carried out by distillation, there are fewer impurities entering the front-end and back-end dehydration membrane devices, reducing the problem that impurities and particles in the organic solvent may clog the membrane pores, reduce the membrane separation effect, or cause membrane damage. Since further purification is carried out by dehydration membrane method, the construction scale and operating cost of the light component separator and heavy component separator can be reduced, while reducing energy consumption. The dehydration device and the deep purification device can further remove colored substances and metal ions in the organic solvent, further ensuring the purification effect. Therefore, the organic solvent purification and recovery device of the present invention can effectively combine distillation and dehydration membrane methods, thereby maintaining a good purification and recovery effect while reducing costs and energy consumption. 2. Through heat exchange between the first condensing pipe and the preheating pipe, and between the second condensing pipe and the preheating pipe, the energy consumption of the first condenser, the second condenser, and the preheater can be reduced simultaneously, thereby improving energy-saving performance. 3. The first spiral tube section is placed in front of the second spiral tube section, so that the organic solvent in the preheating pipeline first exchanges heat with the vaporized light component in the first spiral tube section and then exchanges heat with the vaporized heavy component in the second spiral tube section. This avoids the situation where the heat of the heavy component is transferred to the organic solution first and then the heat of the organic solution is transferred to the light component, thus improving the heat exchange effect. Attached Figure Description

[0017] Figure 1 This is a process flow diagram of the organic solvent purification and recovery device in Example 1; Figure 2 This is a partial structural schematic diagram of the organic solvent purification and recovery device in Example 2; Figure 3 This is a structural cross-sectional view of the high-temperature junction pipe section in Example 2.

[0018] Explanation of reference numerals in the attached drawings: 1. Raw material tank; 2. First filter; 3. Light component separator; 4. First condenser; 5. Light component removal liquid; 6. Second condenser; 7. Heavy component separator; 8. Residue; 9. First relay tank; 10. Front-end dehydration membrane device; 11. Back-end dehydration membrane device; 13. First return pipeline; 14. Preheater; 15. Raw material; 21. Decolorization device; 22. Third condenser; 23. Second relay tank; 24. Deep purification device; 25. Adsorbent material; 26. Second filter; 27. Finished product tank; 28. Finished product liquid; 31. First spiral section; 32. Second spiral section; 33. Preheating pipeline; 34. Low-temperature junction section; 35. High-temperature junction section; 36. Spiral baffle. Detailed Implementation

[0019] The following will be combined with the appendix Figure 1-3 The present invention will be further illustrated by the embodiments.

[0020] Example 1 This embodiment discloses an apparatus for purifying and recovering organic solvents.

[0021] Reference Figure 1The organic solvent purification and recovery device includes a raw liquid tank 1, a light component separator 3, a heavy component separator 7, a first relay tank 9, a front-end dehydration membrane device 10, a rear-end dehydration membrane device 11, a decolorization device 21, a second relay tank 23, a deep purification device 24, and a finished product tank 27, connected sequentially along the preceding and following processes. The raw liquid tank 1 stores the raw liquid 15 to be purified. A first filter 2 is installed between the raw liquid tank 1 and the light component separator 3 to filter the raw liquid 15, reducing impurities entering the light component separator 3. Both the light component separator 3 and the heavy component separator 7 are equipped with heating functions. The light component separator 3 performs vapor-phase separation of the light components in the raw liquid 15 using a low-boiling method. The separated light components are drawn out, while the raw liquid 15 enters the next process. A first condenser 4 is installed along the light component drawing path to condense the vaporized light components for vapor-phase recovery, facilitating the collection of the light component removal liquid 5. The heavy component separator 7 separates the heavy components in the raw liquid 15 through vapor phase separation via high boiling. The separated heavy components enter the next process, while the residue 8 is drawn off. A second condenser 6 is installed along the path of the heavy components entering the next process. The second condenser 6 is used to condense the vaporized heavy components for vapor phase recovery, so that the organic solvent of the heavy components flows into the first relay tank 9. A preheater 14 is installed between the first relay tank 9 and the front-end dehydration membrane device 10. The preheater 14 is used to preheat the organic solvent flowing into the front-end dehydration membrane device 10. The purpose is twofold: First, since the dehydration membranes of the front-end dehydration membrane device 10 and the rear-end dehydration membrane device 11 achieve better dehydration results at specific temperatures, preheating the organic solvent can prevent the organic solvent from causing the dehydration membrane to cool down, thus affecting the dehydration effect. Second, preheating the organic solvent to increase its temperature can increase the kinetic energy of the organic solvent molecules, promoting the faster diffusion of water molecules from the organic solvent, thereby accelerating the dehydration efficiency and effect. The organic solvent, after dehydration by the dehydration membrane, enters the decolorization device 21. At this point, the organic solvent may discolor due to residual pigments or other colored substances on the dehydration membrane. The decolorization device 21 uses flash evaporation to vaporize the heavy components in the organic solvent again, thereby separating them from the residual pigments and other colored substances. A third condenser 22 is installed between the decolorization device 21 and the second relay tank 23. The third condenser 22 is used to condense the vaporized heavy components so that they flow into the second relay tank 23. The deep purification device 24 contains adsorption material 25, which is an ion exchange resin. The deep purification device 24 is used to remove metal ions from the organic solvent, improving the purification effect. A second filter 26 is installed between the deep purification device 24 and the finished product tank 27. The second filter 26 is used for final filtration of impurities in the organic solvent, ultimately forming the finished product liquid 28 which flows into the finished product tank 27.In summary, the light component separator 3 and the heavy component separator 7 utilize distillation to perform preliminary purification of the organic solvent, while the front-end dehydration membrane device 10 and the rear-end dehydration membrane device 11 utilize dehydration membrane technology for further purification. On the one hand, since preliminary purification has already been performed by distillation, fewer impurities enter the front-end dehydration membrane device 10 and the rear-end dehydration membrane device 11, reducing the potential for impurities and particles in the organic solvent to clog membrane pores, reduce membrane separation efficiency, or cause membrane damage. On the other hand, since further purification is achieved through dehydration membrane technology, the construction scale and operating costs of the light component separator 3 and the heavy component separator 7 can be reduced, while also reducing energy consumption. In addition, the dehydration device and the deep purification device 24 can further remove colored substances and metal ions from the organic solvent, further ensuring the purification effect. Therefore, the organic solvent purification and recovery device of the present invention can effectively combine distillation and dehydration membrane methods, thereby maintaining a good purification and recovery effect while reducing costs and energy consumption.

[0022] Reference Figure 1 A first return pipeline 13 connects the front-end dehydration membrane device 10 to the first relay tank 9, and the rear-end dehydration membrane device 11 to the first relay tank 9. When the dehydration effect of the organic solvent in the front-end or rear-end dehydration membrane device 10 is not as expected, the organic solvent can be returned to the first relay tank 9 through the first return pipeline 13 for further dehydration. Additionally, a second return pipeline connects the finished product tank 27 to the first relay tank 9. When the purification effect of the finished product liquid 28 in the finished product tank 27 is not as expected, the finished product liquid 28 can be returned to the first relay tank 9 through the second return pipeline for further purification. Therefore, the arrangement of the first and second return pipelines facilitates the return of unsatisfactory organic solvents or finished product liquid 28 to the first relay tank 9 for further processing, ensuring the purification effect.

[0023] This embodiment discloses a method for purifying and recovering organic solvents.

[0024] Reference Figure 1 The purification and recovery method for organic solvents includes the following steps: S1: The raw liquid 15 in the raw liquid tank 1 is filtered by the first filter 2, and the filtered raw liquid 15 enters the next process. S2: The light components of the raw liquid 15 are separated from the heavy components by the light component separator 3 and the heavy component separator 7 in sequence. The heavy component organic solvent enters the next process. S3: The organic solvent is dehydrated sequentially using the front dehydration membrane device 10 and the rear dehydration membrane device 11; S4: The colored substances in the organic solvent are removed using the decolorization device 21; S5: The metal ions in the organic solvent are removed using the deep purification device 24; S6: The organic solvent is filtered using the second filter 26, and the filtered finished liquid 28 is loaded into the finished product tank 27. In step S3, if the dehydration effect does not meet expectations, the organic solvent is returned to the first relay tank 9 for further dehydration. In step S6, if the effect of the finished product liquid 28 does not meet expectations, the finished product liquid 28 is returned to the first relay tank 9 for further purification.

[0025] Example 2 Reference Figure 1 The path between the first relay tank 9 and the upstream dehydration membrane device 10, where a preheater 14 is installed, is called the preheating pipeline 33. The pipeline on the light component separator 3, where a first condenser 4 is installed, is called the first condensing pipeline. The pipeline between the heavy component separator 7 and the first relay tank 9, where a second condenser 6 is installed, is called the second condensing pipeline. Since the vaporized light and heavy components carry a lot of heat, directly recovering the vaporized light components through the first condenser 4 and directly recovering the vaporized heavy components through the second condenser 6 would result in high energy consumption for both the first condenser 4 and the second condenser 6. Therefore, the organic solvent purification and recovery device of the present invention is further improved in the following ways.

[0026] The difference from Embodiment 1 is that the first condensing pipe and the preheating pipe 33 intersect, with the intersection located in front of the first condenser 4 and the preheater 14, achieving heat exchange between the first condensing pipe and the preheating pipe 33. Similarly, the second condensing pipe intersects with the preheating pipe 33, with the intersection located in front of the second condenser 6 and the preheater 14, achieving heat exchange between the second condensing pipe and the preheating pipe 33. Through this arrangement, on the one hand, by reducing the heat carried by the vaporized light and heavy components, the energy consumption of the first condenser 4 and the second condenser 6 is reduced. On the other hand, by reusing the heat carried by the vaporized light and heavy components to preheat the organic solvent in the preheating pipe 33, the energy consumption of the preheater 14 can be reduced. Therefore, this arrangement can simultaneously reduce the energy consumption of the first condenser 4, the second condenser 6, and the preheater 14, improving energy-saving performance. It should be noted that in this embodiment, "in front" refers to a position closer to the structure in the previous process.

[0027] Reference Figure 2The first condensing pipe includes a first spiral section 31, and the second condensing pipe includes a second spiral section 32. Both the first spiral section 31 and the second spiral section 32 are wound around the preheating pipe 33. The first condensing pipe intersects with the preheating pipe 33 using the first spiral section 31 and the second spiral section 32, which improves the heat exchange effect. Furthermore, the axis of the flow path of the vaporized light component in the first spiral section 31 and the axis of the flow path of the vaporized heavy component in the second spiral section 32 are opposite to the axis of the flow path of the organic solvent in the preheating pipe. This creates a counterbalancing effect between the vaporized light component and the organic solvent, and between the vaporized heavy component and the organic solvent, further enhancing the heat exchange effect. In this embodiment, the first spiral section 31 and the second spiral section 32 also contact the preheating pipe 33, improving heat transfer efficiency and thus enhancing the heat exchange effect.

[0028] Reference Figure 2 Since the light components vaporized in the first condenser tube are produced at low boiling points, while the heavy components vaporized in the second condenser tube are produced at high boiling points, the heat carried by the vaporized light components is lower than that carried by the vaporized heavy components. Therefore, the first spiral tube section 31 is positioned in front of the second spiral tube section 32, allowing the organic solvent in the preheating tube 33 to exchange heat first with the vaporized light components in the first spiral tube section 31 before exchanging heat with the vaporized heavy components in the second spiral tube section 32. This avoids the situation where the heat of the heavy components is first transferred to the organic solution, and then the heat of the organic solution is transferred to the light components, thus improving the heat exchange efficiency.

[0029] Reference Figure 2 and Figure 3Since the heat carried by the vaporized heavy components is greater than the energy carried by the vaporized light components, to more fully utilize the energy carried by the vaporized heavy components, it is necessary to extend the heat transfer time between the organic solvent in the preheating pipe and the heavy components in the second spiral section 32. To this end, the preheating pipe 33 includes a low-temperature junction section 34 and a high-temperature junction section 35. The preheating pipe 33 connects to the first spiral section 31 via the low-temperature junction section 34, and connects to the second spiral section 32 via the high-temperature junction section 35. The inner diameter of the high-temperature junction section 35 is larger than that of the low-temperature junction section 34. Increasing the inner diameter of the high-temperature junction section 35 slows down the flow rate of the organic solution within it, thereby extending the heat transfer time between the organic solvent per unit flow rate and the heavy components in the second spiral section 32, achieving a more efficient reuse of the energy carried by the vaporized heavy components. Furthermore, a spiral baffle 36 is provided along the axis on the inner wall of the high-temperature manifold section 35. The spiral baffle 36 increases the resistance to the flow of the organic solvent within the high-temperature manifold section 35, thus slowing down the flow velocity of the organic solvent within the high-temperature manifold section 35. In addition, the inner diameter of the second spiral section 32 is larger than that of the first spiral section 31. Increasing the inner diameter of the second spiral section 32 slows down the flow velocity of the vaporized heavy components within the second spiral section 32, thereby prolonging the heat transfer time between the organic solvent and the unit flow rate of the heavy components within the second spiral section 32, further achieving the effect of more fully utilizing the energy carried by the vaporized heavy components.

[0030] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A purification and recovery device for organic solvents, characterized in that: The system includes a raw liquid tank (1), a light component separator (3), a heavy component separator (7), a first relay tank (9), a front-end dehydration membrane device (10), a rear-end dehydration membrane device (11), a decolorization device (21), a second relay tank (23), a deep purification device (24), and a finished product tank (27), connected sequentially along the preceding and following processes. A first filter (2) is provided between the raw liquid tank (1) and the light component separator (3). A first condenser (4) is connected to the light component separator (3). A second condenser (6) is provided between the heavy component separator (7) and the first relay tank (9). The first relay tank (9) is connected to the front-end dehydration membrane device (10). A preheater (14) is provided between the first relay tank (9) and the second relay tank (23). A third condenser (22) is provided between the decolorization device (21) and the second relay tank (23). A second filter (26) is provided between the deep purification device (24) and the finished product tank (27). The path of the preheater (14) between the first relay tank (9) and the front dehydration membrane device (10) is a preheating pipeline (33). The pipeline of the first condenser (4) on the light component separator (3) is a first condensing pipeline. The pipeline of the second condenser (6) between the heavy component separator (7) and the first relay tank (9) is a second condensing pipeline. The first condensing pipe includes a first spiral pipe section (31), and the second condensing pipe includes a second spiral pipe section (32). The first spiral pipe section (31) is located in front of the second spiral pipe section (32). The preheating pipe (33) includes a low-temperature junction pipe section (34) and a high-temperature junction pipe section (35). The preheating pipe (33) uses the low-temperature junction pipe section (34) to connect with the first spiral pipe section (31), and the preheating pipe (33) uses the high-temperature junction pipe section (35) to connect with the second spiral pipe section (32). The inner diameter of the high-temperature junction pipe section (35) is larger than the inner diameter of the low-temperature junction pipe section (34). The inner wall of the high-temperature junction pipe section (35) is provided with a spiral baffle (36) along the axis. The inner diameter of the second spiral pipe section (32) is larger than the inner diameter of the first spiral pipe section (31). Both the first spiral tube segment (31) and the second spiral tube segment (32) are wound around the preheating pipe (33).

2. The organic solvent purification and recovery apparatus according to claim 1, characterized by: The front-end dehydration membrane device (10) is connected to the first relay tank (9) by a first return pipeline (13).

3. The organic solvent purification and recovery apparatus according to claim 1, characterized by: A second return pipeline is connected between the downstream dehydration membrane device (11) and the second relay tank (23).

4. The organic solvent purification and recovery apparatus according to claim 3, wherein: The axis of the flow path of the light component in the first spiral section (31) and the axis of the flow path of the heavy component in the second spiral section (32) are opposite to the axis of the flow path of the organic solvent in the preheating pipeline. Both the first spiral section (31) and the second spiral section (32) are in contact with the preheating pipeline (33).

5. A method for purifying and recovering an organic solvent, using an organic solvent purification and recovery apparatus as described in any one of claims 1-4, characterized in that: S1: The raw liquid (15) in the raw liquid tank (1) is filtered using the first filter (2), and the filtered raw liquid (15) enters the next process; S2: The light component separator (3) and the heavy component separator (7) are used in sequence to separate the light components and heavy components of the raw liquid (15), and the heavy component organic solvent enters the next process; S3: The organic solvent is dehydrated sequentially using the front dehydration membrane device (10) and the rear dehydration membrane device (11); S4: The decolorizing device (21) is used to remove the colored substances from the organic solvent; S5: The metal ions of the organic solvent are removed using the deep purification device (24); S6: The organic solvent is filtered using the second filter (26), and the filtered finished liquid (28) is loaded into the finished product tank (27); In S3, if the dehydration effect does not meet expectations, the organic solvent is returned to the first relay tank (9) for dehydration again; in S6, if the effect of the finished liquid (28) does not meet expectations, the finished liquid (28) is returned to the first relay tank (9) for purification again.

6. The application of the organic solvent purification and recovery device according to any one of claims 1-4 in the semiconductor field.

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