Indirect heat pump dichloromethane rectification device for lithium battery diaphragm
By designing an indirect heat pump dichloromethane distillation device in the production of lithium battery separators, and using a high-temperature centrifugal heat pump to circulate and recover hot water, the problem of unrecovered steam heating heat in the prior art is solved, and energy consumption is reduced and process flow is simplified.
Patent Information
- Application Number
- CN202421903299.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-07
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2034-08-07
AI Technical Summary
In the prior art, in the production process of lithium battery separators, a large amount of steam is required to be heated during the separation of dichloromethane and white oil, but the heat of the steam cannot be effectively recovered, resulting in a high overall energy consumption.
A dichloromethane distillation device for lithium battery separator was designed, and hot water was circulated using a high-temperature centrifugal heat pump to circulate and use the hot water between the falling film evaporator and the plate heat exchanger through the output side circulation pipeline to replace traditional steam heating.
The high-temperature centrifugal heat pump consumes less electricity to produce and circulate hot water, which realizes the effective recycling of hot water, reduces comprehensive energy consumption, simplifies the process flow and reduces equipment investment.
Smart Images
Figure CN222983729U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of dichloromethane rectification equipment, and specifically, to an indirect heat pump dichloromethane rectification device for lithium battery diaphragms. Background Art
[0002] In the production process of lithium battery diaphragms, dichloromethane is used to extract white oil pore-forming agent in polyethylene to form a porous polyethylene film. Currently, a white oil-dichloromethane mixture is generated, and the white oil-dichloromethane mixture is separated by a single rectification method. During the process, the dichloromethane vapor generated by rectification is condensed with cold water, and a large amount of steam is required for heating. However, in the prior art, no effective measures are taken to recover the heat of the steam, resulting in high comprehensive energy consumption. In view of the above problems, the prior art has not been well solved, which brings trouble to the normal operation of this field. Therefore, there is an urgent need for an indirect heat pump dichloromethane rectification device for lithium battery diaphragms to solve the above problems. Summary of the Utility Model
[0003] The utility model provides an indirect heat pump dichloromethane rectification device for lithium battery diaphragms, which solves the problem in the related art that a large amount of steam is required for heating and there is no recovery measure, resulting in high comprehensive energy consumption.
[0004] The technical solution of the utility model is as follows: An indirect heat pump dichloromethane rectification device for lithium battery diaphragms includes a main pipeline, a raw material storage tank, a plate heat exchanger, a falling film evaporator, a separator, a high-temperature centrifugal heat pump, and an output-side circulation pipeline. The raw material storage tank, the plate heat exchanger, the falling film evaporator, and the separator are sequentially connected to the main pipeline. Both ends of the output-side circulation pipeline are connected to the high-temperature centrifugal heat pump, and the output-side circulation pipeline is sequentially connected to the falling film evaporator and the plate heat exchanger for circulating the hot water produced by the high-temperature centrifugal heat pump among the high-temperature centrifugal heat pump, the falling film evaporator, and the plate heat exchanger.
[0005] Optionally, it further includes a primary condenser, which is arranged on the main pipeline for condensing the dichloromethane vapor separated by the separator.
[0006] Optionally, it further includes an input-side circulation pipeline, both ends of which are respectively connected to the high-temperature centrifugal heat pump, and the input-side circulation pipeline passes through the primary condenser for transferring the heat in the dichloromethane vapor to the input-side circulation pipeline.
[0007] Optionally, it further includes a secondary condenser, which is arranged on the main pipeline for condensing the dichloromethane output by the primary condenser.
[0008] Optionally, it further includes a cold water pipeline which passes through the secondary condenser and is used to supply cold water required for condensation to the secondary condenser.
[0009] Optionally, it further includes a finished dichloromethane storage tank which is arranged on the main pipeline and is used to store the liquid dichloromethane output by the secondary condenser.
[0010] Optionally, it further includes a mixed liquid buffer tank which is arranged on the main pipeline and is used to store the liquid white oil-dichloromethane mixed liquid separated by the separator.
[0011] Optionally, it further includes a first reflux pipeline whose two ends are respectively connected to the primary condenser and the separator, and is used to reflux a part of the dichloromethane output by the primary condenser to the separator.
[0012] Optionally, it further includes a second reflux pipeline whose two ends are respectively connected to the main pipeline and the falling film evaporator, and the connection point of the second reflux pipeline and the main pipeline is located between the separator and the mixed liquid buffer tank, and is used to reflux a part of the white oil-dichloromethane mixed liquid output by the separator to the falling film evaporator.
[0013] Optionally, it further includes a feed pump, a circulation pump and a discharge pump. The feed pump, the circulation pump and the discharge pump are all connected to the main pipeline. The feed pump is located between the raw material storage tank and the plate heat exchanger, and the circulation pump and the discharge pump are located between the separator and the mixed liquid buffer tank.
[0014] The working principle and beneficial effects of the present utility model are as follows:
[0015] A raw material storage tank, a plate heat exchanger, a falling film evaporator and a separator are sequentially connected on the main pipeline. Moreover, a high-temperature centrifugal heat pump and an output-side circulation pipeline are innovatively added. Both ends of the output-side circulation pipeline are connected to the high-temperature centrifugal heat pump. The high-temperature centrifugal heat pump can produce high-temperature hot water at about 80°C with a small amount of electricity. The output-side circulation pipeline is used to circulate the hot water, and the temperature of the return water is about 65°C. Moreover, the output-side circulation pipeline is sequentially connected to the falling film evaporator and the plate heat exchanger, and can circulate the produced hot water among the high-temperature centrifugal heat pump, the falling film evaporator and the plate heat exchanger.
[0016] During operation, a mixed liquid of white oil and dichloromethane is stored in the raw material storage tank. It is first pumped under pressure and sent to a plate heat exchanger for heating, then fed into the top of a falling film evaporator for evaporation, and then discharged from the bottom of the falling film evaporator to a separator to separate the gaseous dichloromethane and the liquid white oil-dichloromethane mixed liquid. During the process, the heating heat source of the falling film evaporator uses the hot water circulated by a high-temperature centrifugal heat pump, while the heating heat source of the plate heat exchanger uses the hot water recovered from the falling film evaporator, thus completing the recycling of hot water.
[0017] By consuming less electricity, the high-temperature centrifugal heat pump produces and circulates hot water, replacing traditional steam as the heating heat source of the falling film evaporator. Moreover, the hot water recovered from the falling film evaporator is also used as the heating source of the plate heat exchanger, achieving good recycling of hot water, simplifying the process flow, reducing equipment investment, and solving the problem in the prior art that a large amount of steam is required for heating during the dichloromethane separation process and no effective heat recovery measures are taken for the heat of the steam, resulting in high comprehensive energy consumption. Brief Description of the Drawings
[0018] The following will further illustrate the above characteristics, technical features, advantages and their implementation manners of the present utility model in a clear and understandable manner in combination with the drawings of the preferred embodiments.
[0019] Figure 1 It is a structural schematic diagram of an indirect heat pump dichloromethane rectification device for a lithium battery separator.
[0020] In the figure: 1, main pipeline; 2, raw material storage tank; 3, plate heat exchanger; 4, falling film evaporator; 5, separator; 6, high-temperature centrifugal heat pump; 7, output side circulation pipeline; 8, primary condenser; 9, input side circulation pipeline; 10, secondary condenser; 11, cold water pipeline; 12, dichloromethane finished product storage tank; 13, mixed liquid buffer tank; 14, return pipeline one; 15, return pipeline two; 16, feed pump; 17, circulation pump; 18, discharge pump. Detailed Embodiments
[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the specific embodiments of the present utility model will be described below with reference to the drawings. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings and other embodiments can be obtained.
[0022] For the sake of simplicity of the drawings, only the parts related to the utility model are schematically shown in each figure, and they do not represent the actual structure of the product as a whole. Additionally, for the sake of simplicity and easy understanding of the drawings, in some figures, only one of the components with the same structure or function is schematically shown, or only one of them is labeled. In this article, "one" not only means "only this one", but also can mean "more than one" situation, and "several" includes "two" and "more than two".
[0023] In this article, it should be noted that unless otherwise clearly stipulated and defined, the terms "installation", "connection", and "linkage" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in this utility model can be understood according to specific situations.
[0024] In addition, in the description of this application, the terms "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.
[0025] Referring to Figure 1 , for the first embodiment of the present utility model, an indirect heat pump dichloromethane rectification device for a lithium battery separator is proposed, which includes a main pipeline 1, a raw material storage tank 2, a plate heat exchanger 3, a falling film evaporator 4, a separator 5, a high-temperature centrifugal heat pump 6, and an output-side circulation pipeline 7. The raw material storage tank 2, the plate heat exchanger 3, the falling film evaporator 4, and the separator 5 are sequentially connected to the main pipeline 1. Both ends of the output-side circulation pipeline 7 are connected to the high-temperature centrifugal heat pump 6. The output-side circulation pipeline 7 is sequentially connected to the falling film evaporator 4 and the plate heat exchanger 3, and is used to circulate the hot water produced by the high-temperature centrifugal heat pump 6 among the high-temperature centrifugal heat pump 6, the falling film evaporator 4, and the plate heat exchanger 3.
[0026] In this embodiment, a raw material storage tank 2, a plate heat exchanger 3, a falling film evaporator 4, and a separator 5 are sequentially connected to the main pipeline 1. Additionally, a high-temperature centrifugal heat pump 6 and an output-side circulation pipeline 7 are innovatively added. Both ends of the output-side circulation pipeline 7 are connected to the high-temperature centrifugal heat pump 6. The high-temperature centrifugal heat pump 6 can produce high-temperature hot water at about 80°C with a small amount of electricity. The output-side circulation pipeline 7 is used to circulate the hot water, and the temperature of the return water is about 65°C. Moreover, the output-side circulation pipeline 7 is sequentially connected to the falling film evaporator 4 and the plate heat exchanger 3, and can circulate the produced hot water among the high-temperature centrifugal heat pump 6, the falling film evaporator 4, and the plate heat exchanger 3.
[0027] During operation, the raw material storage tank 2 stores a mixture of white oil and methylene chloride. The mixture is first pumped under pressure and sent to the plate heat exchanger 3 for heating, then fed into the falling film evaporator 4 from the top for evaporation, and then discharged from the bottom of the falling film evaporator 4 to the separator 5 to separate the gaseous methylene chloride and the liquid white oil-methylene chloride mixture. During the process, the heating heat source of the falling film evaporator 4 uses the hot water circulated by the high-temperature centrifugal heat pump 6, while the heating heat source of the plate heat exchanger 3 uses the hot water recovered from the falling film evaporator 4, thus completing the recycling of hot water.
[0028] The high-temperature centrifugal heat pump 6 consumes less electricity to produce and circulate hot water, replacing the traditional steam as the heating heat source of the falling film evaporator 4. Moreover, the hot water recovered from the falling film evaporator 4 is also used as the heating source of the plate heat exchanger 3, realizing a good recycling of hot water, simplifying the process flow, reducing equipment investment, and solving the problem in the prior art that a large amount of steam is required for heating during the separation process of methylene chloride and no effective heat recovery measures are taken for the heat of the steam, resulting in a relatively high comprehensive energy consumption.
[0029] It also includes a primary condenser 8, and the primary condenser 8 is arranged on the main pipeline 1 for condensing the methylene chloride vapor separated by the separator 5.
[0030] It also includes an input-side circulation pipeline 9. Both ends of the input-side circulation pipeline 9 are respectively connected to the high-temperature centrifugal heat pump 6, and the input-side circulation pipeline 9 passes through the primary condenser 8 for transferring the heat in the methylene chloride vapor to the input-side circulation pipeline 9.
[0031] In this embodiment, the high-purity methylene chloride vapor at about 42°C separated by the separator 5 enters the primary condenser 8, and the input-side circulation pipeline 9 passes through the primary condenser 8, so as to realize the heat exchange between the high-purity methylene chloride entering the primary condenser 8 and the water in the input-side circulation pipeline 9. The water temperature entering the primary condenser 8 is about 30°C, and the outlet water temperature is about 35°C. Thus, while maintaining the evaporation temperature input to the high-temperature centrifugal heat pump 6 and realizing the condensation of methylene chloride vapor, the heat is also transferred to the high-temperature centrifugal heat pump 6 through the evaporation of the refrigerant.
[0032] It also includes a secondary condenser 10, and the secondary condenser 10 is arranged on the main pipeline 1 for condensing the methylene chloride output by the primary condenser 8.
[0033] It also includes a cold water pipeline 11, and the cold water pipeline 11 passes through the secondary condenser 10 for providing the cold water required for condensation for the secondary condenser 10.
[0034] It also includes a dichloromethane finished product storage tank 12, which is arranged on the main pipeline 1 and used to store the liquid dichloromethane output by the secondary condenser 10.
[0035] In this embodiment, the dichloromethane output by the primary condenser 8 enters the secondary condenser 10. The cold water pipeline 11 passes through the secondary condenser 10 to provide the cold water required for condensation for the secondary condenser 10. The inlet water temperature is about 7°C and the outlet water temperature is about 12°C. The dichloromethane is condensed into a liquid after heat exchange in the secondary condenser 10 and finally discharged to the dichloromethane finished product storage tank 12.
[0036] It also includes a mixed liquid buffer tank 13, which is arranged on the main pipeline 1 and used to store the liquid white oil dichloromethane mixed liquid separated by the separator 5.
[0037] In this embodiment, the liquid white oil dichloromethane mixed liquid separated on the other side of the separator 5 is concentrated and then discharged to the mixed liquid buffer tank 13 by pump pressurization to ensure safe storage.
[0038] It also includes a first reflux pipeline 14, the two ends of which are respectively connected to the primary condenser 8 and the separator 5, and is used to reflux a part of the dichloromethane output by the primary condenser 8 to the separator 5.
[0039] In this embodiment, among the dichloromethane output by the primary condenser 8, most of it is discharged to the secondary condenser 10 for heat exchange and condensation, and a small part is refluxed to the separator 5 through the first reflux pipeline 14 to achieve rectification reflux, thereby improving the purity of the final dichloromethane product.
[0040] It also includes a second reflux pipeline 15, the two ends of which are respectively connected to the main pipeline 1 and the falling film evaporator 4. The connection point of the second reflux pipeline 15 and the main pipeline 1 is located between the separator 5 and the mixed liquid buffer tank 13, and is used to reflux a part of the white oil dichloromethane mixed liquid output by the separator 5 to the falling film evaporator 4.
[0041] In this embodiment, among the liquid white oil dichloromethane mixed liquid separated by the separator 5, most of it is discharged to the mixed liquid buffer tank 13 for storage by pump pressurization, and a small part is refluxed to the top of the falling film evaporator 4 for feeding through the second reflux pipeline 15 to achieve rectification reflux, thereby further improving the purity of the final dichloromethane product.
[0042] It further includes a feed pump 16, a circulation pump 17 and a discharge pump 18. The feed pump 16, the circulation pump 17 and the discharge pump 18 are all connected to the main pipeline 1. The feed pump 16 is located between the raw material storage tank 2 and the plate heat exchanger 3, and the circulation pump 17 and the discharge pump 18 are located between the separator 5 and the mixed liquid buffer tank 13.
[0043] In this embodiment, the feed pump 16 provides the power for the raw material storage tank 2 to discharge materials outward. The circulation pump 17 is used to provide the operation of the overall system, and the discharge pump 18 is used to discharge most of the liquid white oil dichloromethane mixed liquid separated by the separator 5 to the mixed liquid buffer tank 13 for storage.
[0044] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.
Claims
1. An indirect heat pump dichloromethane distillation device for lithium battery diaphragm, characterized in that: The invention comprises a main pipeline (1), a raw material storage tank (2), a plate heat exchanger (3), a falling film evaporator (4), a separator (5), a high-temperature centrifugal heat pump (6) and an output side circulation pipeline (7), wherein the raw material storage tank (2), the plate heat exchanger (3), the falling film evaporator (4) and the separator (5) are connected to the main pipeline (1) in sequence, both ends of the output side circulation pipeline (7) are connected to the high-temperature centrifugal heat pump (6), and the output side circulation pipeline (7) is connected to the falling film evaporator (4) and the plate heat exchanger (3) in sequence, and is used for circulating the hot water produced by the high-temperature centrifugal heat pump (6) among the high-temperature centrifugal heat pump (6), the falling film evaporator (4) and the plate heat exchanger (3).
2. The indirect heat pump dichloromethane distillation device for lithium battery diaphragm according to claim 1, characterized in that: It also includes a primary condenser (8), which is arranged on the main pipeline (1) and is used to condense the dichloromethane vapor separated by the separator (5).
3. The indirect heat pump dichloromethane distillation device for lithium battery diaphragm according to claim 2, characterized in that: It also includes an input-side circulation pipeline (9), both ends of which are respectively connected to the high-temperature centrifugal heat pump (6), and the input-side circulation pipeline (9) passes through the primary condenser (8) and is used to transfer heat in the dichloromethane vapor to the input-side circulation pipeline (9).
4. The indirect heat pump dichloromethane distillation device for lithium battery diaphragm according to claim 3, characterized in that: It also comprises a secondary condenser (10), wherein the secondary condenser (10) is arranged on the main pipeline (1) and is used for condensing the dichloromethane outputted from the primary condenser (8).
5. The indirect heat pump dichloromethane distillation device for lithium battery diaphragm according to claim 4, characterized in that: It also includes a cold water pipeline (11), which passes through the secondary condenser (10) and is used to provide the secondary condenser (10) with cold water required for condensation.
6. The indirect heat pump dichloromethane distillation device for lithium battery diaphragm according to claim 4, characterized in that: It also includes a dichloromethane finished product storage tank (12), which is arranged on the main pipeline (1) and is used to store liquid dichloromethane output from the secondary condenser (10).
7. The indirect heat pump dichloromethane distillation device for lithium battery diaphragm according to claim 1, characterized in that: It also comprises a mixed liquid buffer tank (13), which is arranged on the main pipeline (1) and is used to store the liquid white oil and dichloromethane mixed liquid separated by the separator (5).
8. The indirect heat pump dichloromethane distillation device for lithium battery diaphragm according to claim 2, characterized in that: The device further comprises a reflux pipeline (14), the two ends of which are respectively connected to the primary condenser (8) and the separator (5), and is used for refluxing a portion of the dichloromethane output from the primary condenser (8) to the separator (5).
9. The indirect heat pump dichloromethane distillation device for lithium battery diaphragm according to claim 7, characterized in that: It also comprises a second reflux pipeline (15), the two ends of which are respectively connected to the main pipeline (1) and the falling film evaporator (4), and the connection point between the second reflux pipeline (15) and the main pipeline (1) is located between the separator (5) and the mixed liquid buffer tank (13), and is used to reflux a portion of the white oil dichloromethane mixed liquid output from the separator (5) to the falling film evaporator (4).
10. The indirect heat pump dichloromethane distillation device for lithium battery diaphragm according to claim 7, characterized in that: The invention also comprises a feed pump (16), a circulation pump (17) and a discharge pump (18), wherein the feed pump (16), the circulation pump (17) and the discharge pump (18) are all connected to the main pipeline (1), the feed pump (16) is located between the raw material storage tank (2) and the plate heat exchanger (3), and the circulation pump (17) and the discharge pump (18) are located between the separator (5) and the mixed liquid buffer tank (13).