Dichloromethane and white oil mixed liquid treatment system

Abstract

The utility model discloses a dichloromethane and white oil mixed liquid treatment system which comprises a storage tank, a first conveying pipeline is installed on the storage tank, the end, away from the storage tank, of the first conveying pipeline is connected with a heat exchange structure A, a second conveying pipeline is installed on the heat exchange structure A, and a heat exchange structure B is installed at the end, away from the heat exchange structure A, of the second conveying pipeline. The heat exchange structure B is connected with the high-temperature rectification device through a third conveying pipeline. The device is simple in structure, heat energy of white oil subjected to high-temperature rectification treatment and heat energy of steam condensate water are reutilized, heat exchange and cooling can be achieved, and energy consumption of circulating water and chilled water can be saved; meanwhile, after the dichloromethane-white oil mixed liquid is subjected to two-stage heat exchange, the initial temperature is increased, and the problems of temperature fluctuation, steam supply intermittency, flow fluctuation and the like possibly occurring when a low-temperature medium is heated by high-temperature steam can be solved.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium battery diaphragm preparation, in particular to a dichloromethane and white oil mixed liquid processing system. Background Art

[0002] The lithium battery diaphragm industry usually uses white oil as a porogen in the wet film making process. The white oil inside the diaphragm is eluted by a low-boiling point, volatile solvent: dichloromethane during the extraction process, thereby forming a microporous structure. The eluted dichloromethane-white oil mixture usually contains 5 to 15wt% white oil. The dichloromethane-white oil mixture is usually treated by distillation. During the distillation process, the dichloromethane that becomes gaseous due to heat is condensed into liquid for recovery. After the white oil is distilled at high temperature, the low volatile components are removed and recovered. The recovered white oil and dichloromethane are reused as materials in the production process for recycling.

[0003] At present, the heat source of the dichloromethane-white oil mixture in the distillation process is usually high-pressure steam, which has the problems of intermittent supply and flow fluctuation. After the high-temperature steam is used to heat the dichloromethane-white oil mixture, steam condensate water with a large amount of thermal energy will be generated; the temperature of the white oil after high-temperature distillation is usually greater than 100°C; it needs to be recycled after heat exchange and cooling with circulating water or deep cooling water. Therefore, a dichloromethane-white oil mixture treatment system is proposed. Utility Model Content

[0004] The utility model aims to provide a dichloromethane-white oil mixed liquid processing system to solve the problem that the dichloromethane-white oil mixed liquid generates steam condensed water and high-temperature white oil in the distillation process and needs to be cooled by circulating water or deep cooling water before recovery.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a dichloromethane white oil mixed liquid processing system, comprising a storage tank, a first delivery pipeline is installed on the storage tank, the end of the first delivery pipeline away from the storage tank is connected to a heat exchange structure A, a second delivery pipeline is installed on the heat exchange structure A, a heat exchange structure B is installed on the end of the second delivery pipeline away from the heat exchange structure A, the heat exchange structure B is connected to a high-temperature distillation device through a third delivery pipeline, and a fourth delivery pipeline connected to the heat exchange structure A and a fifth delivery pipeline connected to the heat exchange structure B are respectively installed on the high-temperature distillation device.

[0006] As a further solution of the utility model: the first delivery pipeline is located between the storage tank and the heat exchange structure A and is equipped with a delivery pump.

[0007] As a further solution of the utility model: the heat exchange structure A is provided with a sixth delivery pipeline.

[0008] As a further solution of the utility model: the heat exchange structure B is provided with a seventh delivery pipeline.

[0009] As a further solution of the utility model: an eighth delivery pipeline is provided on the high-temperature distillation device.

[0010] Compared with the prior art, the utility model has the following beneficial effects: by reusing the heat energy of the white oil after high-temperature distillation treatment and the heat energy of the steam condensed water, not only heat exchange and cooling can be achieved, but also the energy consumption of circulating water and chilled water can be saved; at the same time, after the dichloromethane-white oil mixed liquid undergoes two-stage heat exchange, the initial temperature is improved, which can improve the temperature fluctuation that may occur when the high-temperature steam heats the low-temperature medium, as well as the problems of intermittent steam supply and flow fluctuation. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of a dichloromethane and white oil mixed liquid treatment system of the utility model;

[0012] In the figure: 1. storage tank; 11. first delivery pipeline; 2. delivery pump; 3. heat exchange structure A; 31. second delivery pipeline; 32. sixth delivery pipeline; 4. heat exchange structure B; 41. third delivery pipeline; 42. seventh delivery pipeline; 5. high-temperature distillation device; 51. fourth delivery pipeline; 52. fifth delivery pipeline; 53. eighth delivery pipeline. DETAILED DESCRIPTION

[0013] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0014] See also Figure 1 In an embodiment of the utility model, a dichloromethane white oil mixed liquid processing system includes a storage tank 1, a first delivery pipeline 11 is installed on the storage tank 1, the end of the first delivery pipeline 11 away from the storage tank 1 is connected to the heat exchange structure A3, a second delivery pipeline 31 is installed on the heat exchange structure A3, and a heat exchange structure B4 is installed on the end of the second delivery pipeline 31 away from the heat exchange structure A3. Both the heat exchange structure A3 and the heat exchange structure B4 are shell and tube heat exchangers. The heat exchange structure B4 is connected to a high-temperature distillation device 5 through a third delivery pipeline 41. The high-temperature distillation device 5 is respectively equipped with a fourth delivery pipeline 51 connected to the heat exchange structure A3 and a fifth delivery pipeline 52 connected to the heat exchange structure B4.

[0015] When in use, the storage tank 1 is used to store the dichloromethane-white oil mixed liquid. Then the dichloromethane-white oil mixed liquid in the storage tank 1 enters the interior of the heat exchange structure A3 through the first delivery pipeline 11, and then enters the interior of the heat exchange structure B4 through the second delivery pipeline 31, and then enters the interior of the high-temperature distillation device 5 through the third delivery pipeline 41 to separate the liquids by using the boiling point difference between dichloromethane and white oil. The low-volatile components of the white oil in the mixed liquid inside the high-temperature distillation device 5 are removed by high temperature, and the remaining white oil The temperature is as high as 70-80°C, and the remaining white oil enters the heat exchange structure A3 through the fourth delivery pipeline 51, wherein the tube-side liquid of the heat exchange structure A3 is a cold medium, i.e., a dichloromethane-white oil mixture, with a temperature of about 10-15°C; the shell-side liquid of the heat exchange structure A3 is a hot medium, i.e., the high-temperature white oil produced in the high-temperature distillation device, with a temperature of about 70-80°C. The two media exchange heat in the heat exchange structure A3 by convection, the high-temperature white oil is cooled, and the dichloromethane-white oil mixture is heated, thereby completing the first-stage heat exchange. Heat; at this time, the temperature of the dichloromethane-white oil mixture entering the heat exchange structure B4 is higher than the temperature entering the heat exchange structure A3. After the high-temperature steam is heat exchanged in the high-temperature distillation device 5, the steam condensate generated is sent to the heat exchange structure B4 through the fifth delivery pipeline 52 to provide a heat source for the structure. The tube-side liquid of the heat exchange structure B4 is a cold medium, that is, a dichloromethane-white oil mixture, with a temperature of about 25-30°C; the shell-side liquid of the heat exchange structure B4 is a hot medium, that is, steam condensate generated after the high-temperature steam heat exchange, with a temperature of about 100-110°C. The two media are convectively heat exchanged in the heat exchange structure B4, and the dichloromethane-white oil mixture is heated again to complete the secondary heat exchange. At this time, the temperature of the mixed liquid entering the high-temperature distillation device 5 is higher than the temperature of the mixed liquid entering the heat exchange structure B4. While preheating the mixed liquid, it has a good energy-saving effect. The initial temperature has been improved, which can improve the temperature fluctuation that may occur when the high-temperature steam heats the low-temperature medium, as well as the problems of intermittent steam supply and flow fluctuation.

[0016] See also Figure 1 In one embodiment, in this embodiment, preferably, the first delivery pipeline 11 is located between the storage tank 1 and the heat exchange structure A3 and is equipped with a delivery pump 2. Further, under the action of the delivery pump 2, pressure can be applied to ensure that the dichloromethane-white oil mixture in the storage tank 1 can smoothly enter the subsequent process.

[0017] See also Figure 1 In one embodiment, in this embodiment, preferably, a sixth delivery pipeline 32 is provided on the heat exchange structure A3, and further, the white oil after heat exchange is discharged from the heat exchange structure A3.

[0018] See also Figure 1In one embodiment, in this embodiment, preferably, a seventh delivery pipeline 42 is provided on the heat exchange structure B4, and further, the condensed water after heat exchange is discharged from the heat exchange structure B4.

[0019] See also Figure 1 In one embodiment, in this embodiment, preferably, an eighth delivery pipeline 53 is provided on the high-temperature distillation device 5. Further, high-temperature steam enters the interior of the high-temperature distillation device 5 through the eighth delivery pipeline 53, and liquid separation is performed by utilizing the boiling point difference between dichloromethane and white oil.

[0020] Although this specification is described according to implementation modes, not every implementation mode includes only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0021] Therefore, the above description is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application; that is, all equivalent changes made according to the scope of the claims of the present application are within the protection scope of the claims of the present application.

Claims

1. A dichloromethane white oil mixed liquid treatment system, comprising a storage tank (1), characterized in that: The storage tank (1) is provided with a first delivery pipeline (11), the end of the first delivery pipeline (11) away from the storage tank (1) is connected to a heat exchange structure A (3), the heat exchange structure A (3) is provided with a second delivery pipeline (31), the end of the second delivery pipeline (31) away from the heat exchange structure A (3) is provided with a heat exchange structure B (4), the heat exchange structure B (4) is connected to a high-temperature distillation device (5) via a third delivery pipeline (41), and the high-temperature distillation device (5) is provided with a fourth delivery pipeline (51) connected to the heat exchange structure A (3) and a fifth delivery pipeline (52) connected to the heat exchange structure B (4), respectively.

2. The dichloromethane white oil mixed liquid treatment system according to claim 1, characterized in that: The first delivery pipeline (11) is located between the storage tank (1) and the heat exchange structure A (3) and is equipped with a delivery pump (2).

3. The dichloromethane white oil mixed liquid treatment system according to claim 1, characterized in that: The heat exchange structure A (3) is provided with a sixth delivery pipeline (32).

4. The dichloromethane white oil mixed liquid treatment system according to claim 1, characterized in that: The heat exchange structure B (4) is provided with a seventh delivery pipeline (42).

5. The dichloromethane white oil mixed liquid treatment system according to claim 1, characterized in that: The high-temperature distillation device (5) is provided with an eighth delivery pipeline (53).

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