Electrolyte multistage condensation distillation recovery device

Abstract

This utility model discloses a multi-stage condensation distillation recovery device for electrolyte, including a horizontally arranged sleeve-shaped distillation tank, with a cavity formed between the inner and outer walls of the distillation tank, and an inner cavity inside the inner wall; a heating sleeve is installed in the cavity, and a conveyor belt is installed through the inner cavity and extends to both sides thereon; both ends of the distillation tank are provided with sealing plates with reserved openings; an air inlet is provided at the end of the distillation tank near the feeding direction, and the air inlet is connected to an inert gas tank through an air inlet pipe; an air outlet is provided at the end of the distillation tank near the discharging direction, and the air outlet is connected to a condensation device through a discharge pipe; an induced draft fan is installed on the discharge pipe; the condensation device includes multiple U-shaped working fluid pipes connected in sequence, and the bottom of each of the multiple U-shaped working fluid pipes is connected to a corresponding collection tank through a liquid discharge pipe; by adopting distillation in an inert environment and multi-stage condensation technology, the oxidation of electrolyte components is effectively avoided, the purity and quality of the recovered product are improved, and the recovery cost is reduced.

Description

Technical Field

[0001] This utility model belongs to the field of retired battery recycling technology, and relates to a retired battery electrolyte recycling device, specifically a multi-stage condensation distillation recycling device for electrolyte. Background Technology

[0002] In the current booming development of the new energy industry, lithium batteries, with their advantages of high energy density and long cycle life, are widely used in electric vehicles, energy storage systems, 3C products, and other fields. As the usage of lithium batteries continues to increase, their recycling and disposal after retirement has become crucial. Effective recovery of the electrolyte is a key step in lithium battery recycling technology. The organic solvents and lithium salts contained in the electrolyte, if properly recycled and reused, can not only reduce resource waste but also reduce environmental pollution. However, existing lithium battery recycling technologies have many drawbacks. Traditional distillation devices mostly operate under normal pressure, causing some components in the electrolyte to easily decompose and oxidize at higher temperatures, reducing the purity and quality of the recycled products. At the same time, existing devices lack comprehensive exhaust gas treatment systems, and the exhaust gases containing harmful components such as fluorides and organic solvent vapors generated during the distillation process are directly emitted, posing a serious threat to the environment and the health of operators. Furthermore, the overall recycling process of existing devices is inefficient and cannot meet the growing demand for lithium battery recycling. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the purpose of this invention is to provide a multi-stage condensation distillation recovery device for electrolytes. By employing distillation in an inert environment and multi-stage condensation technology, the oxidation of electrolyte components is effectively avoided, thereby improving the purity and quality of the recovered products and reducing recovery costs.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] An electrolyte multi-stage condensation distillation recovery device includes a distillation tank arranged horizontally. The side wall of the distillation tank is configured as a sleeve shape including an inner wall and an outer wall, and a cavity is formed between the inner wall and the outer wall. An inner cavity is provided inside the inner wall.

[0006] A heating sleeve is provided inside the cavity, and a conveyor belt extends laterally through the distillation tank to both sides inside the cavity.

[0007] Both ends of the distillation tank are equipped with sealing plates, and the sealing plates are provided with openings for the conveyor belt to pass through; the openings are provided with flexible seals.

[0008] The distillation tank is provided with an air inlet at one end near the feed direction, and the air inlet is connected to an inert gas tank through an air inlet pipe;

[0009] The distillation tank is provided with a gas outlet at one end near the discharge direction, and the gas outlet is connected to a condenser through a discharge pipe;

[0010] An induced draft fan is installed on the discharge pipe;

[0011] The condensation device includes a shell, inside which are vertically arranged multiple U-shaped working fluid pipes connected in sequence. The top of the U-shaped working fluid pipe near the first end is connected to the discharge pipe of the distillation tank through a feed inlet located at the top of the shell; the bottom of the multiple U-shaped working fluid pipes are respectively connected to the corresponding collection tank through liquid discharge pipes.

[0012] The housing has a cooling medium inlet near the bottom and a cooling medium outlet near the top.

[0013] Preferably, both the air inlet pipe and the discharge pipe are equipped with a flow meter and a flow regulating switch.

[0014] Preferably, the distillation vessel is equipped with a thermometer for monitoring the temperature of the inner cavity.

[0015] Preferably, the heating sleeve is connected to a controller for adjusting the heating temperature.

[0016] Preferably, the collection tank connected to the U-shaped working fluid pipe at the end is an end collection tank, and the end collection tank is equipped with a tail gas absorbent.

[0017] Furthermore, the exhaust gas absorbent includes a physical adsorbent and a chemical adsorbent arranged in layers.

[0018] Furthermore, the physical adsorbent is honeycomb activated carbon.

[0019] Compared with the prior art, this utility model has the following technical effects:

[0020] This invention heats the electrolyte in an inert gas environment. Through heating and airflow guidance, a negative pressure is formed in the inner cavity of the distillation tank, which reduces the boiling temperature of the electrolyte, increases vaporization efficiency, and reduces the oxidation and decomposition of the electrolyte. Furthermore, through a multi-stage condensation design, components with different dew points in the gas are separated, achieving low-energy consumption and high-efficiency recovery of the electrolyte. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of this utility model;

[0022] The meanings of the labels in the diagram are as follows: 1-Distillation tank, 101-Inner wall, 102-Outer wall, 103-Heating jacket, 104-Sealing plate, 2-Conveyor belt, 3-Opening, 4-Inlet pipe, 5-Inert gas tank, 6-Discharge pipe, 7-Condensation device, 701-Shell, 702-U-shaped working fluid pipe, 703-Liquid discharge pipe, 8-Collection tank, 801-End collection tank. Detailed Implementation

[0023] The specific content of this utility model will be further explained in detail below with reference to the embodiments.

[0024] like Figure 1 As shown, this embodiment provides an electrolyte multi-stage condensation distillation recovery device, including a distillation tank 1 arranged horizontally. The side wall of the distillation tank 1 is configured as a sleeve shape including an inner wall 101 and an outer wall 102. A cavity is formed between the inner wall 101 and the outer wall 102, and an inner cavity is provided inside the inner wall.

[0025] A heating sleeve 103 is installed inside the cavity, and a conveyor belt 2 extends laterally through the distillation tank 1 to both sides inside the cavity. A thermometer is installed on the distillation tank 1 to monitor the temperature of the cavity. The heating sleeve 103 is connected to a controller to adjust the heating temperature. The heating sleeve 103 heats the cavity, so that the electrolyte passing through the cavity on the conveyor belt 2 is heated. Some organic matter and binder are vaporized by heating, and the remaining substances continue to remain on the conveyor belt 2 and are output from the discharge end of the distillation tank 1.

[0026] Both ends of the distillation tank 1 are provided with sealing plates 104, and the sealing plates 104 are provided with openings 3 for the conveyor belt 2 to pass through; the openings 3 are provided with flexible seals; the sealing plates 104 and flexible seals are used to prevent the gas and vaporized substances in the inner cavity from escaping.

[0027] The distillation tank 1 is provided with an air inlet at one end near the feeding direction, and the air inlet is connected to an inert gas tank 5 through an air inlet pipe 4; the distillation tank 1 is provided with an air outlet at one end near the discharging direction, and the air outlet is connected to a condenser 7 through a discharge pipe 6; the inert gas tank 5 is used to introduce inert gas to prevent the vaporized substances in the electrolyte from oxidizing.

[0028] An induced draft fan is installed on the discharge pipe 6; flow meters and flow regulating switches are installed on both the air inlet pipe 4 and the discharge pipe 6. The induced draft fan is used to guide the airflow and at the same time create a negative pressure in the inner cavity of the distillation tank 1, which reduces the boiling temperature of the electrolyte, increases the vaporization efficiency, and reduces the oxidation and decomposition of the electrolyte.

[0029] The condenser 7 includes a housing 701, inside which are vertically arranged multiple U-shaped working fluid pipes 702 connected in sequence. The top of the U-shaped working fluid pipe 702 near the beginning is connected to the discharge pipe 6 of the distillation tank 1 through an inlet located at the top of the housing 701. The bottoms of the multiple U-shaped working fluid pipes 702 are respectively connected to corresponding collection tanks 8 through liquid discharge pipes 703. The collection tank connected to the U-shaped working fluid pipe 702 at the end is a terminal collection tank 801, which contains a tail gas absorbent. Preferably, the U-shaped working fluid pipes 702 are connected in three stages in sequence.

[0030] The end collection tank 801 includes a bottom liquid collection chamber, a middle physical absorption chamber, and a top chemical absorption tank. One side of the chemical absorption tank has an opening that connects to the bottom. Liquid flowing out of the liquid discharge pipe 703 at the bottom of the U-shaped working medium pipe 702 at the end is collected into the bottom liquid collection chamber. Gas rises and is absorbed by the physical absorption chamber. The remaining gas condenses downward and mixes with the liquid in the liquid collection chamber. The gas that cannot be condensed is absorbed by the chemical absorption tank and then discharged.

[0031] Exhaust gas absorbents include physical adsorbents and chemical adsorbents arranged in layers.

[0032] The physical adsorbent is honeycomb activated carbon.

[0033] The housing 701 has a cooling medium inlet near the bottom and a cooling medium outlet near the top.

[0034] The organic components in lithium battery electrolyte and their corresponding boiling points are as follows: ethylene carbonate (EC) (boiling point: 248℃), dimethyl carbonate (DMC) (boiling point: 90℃), diethyl carbonate (DEC) (boiling point: 125.8℃), and methyl ethyl carbonate (EMC) (boiling point: 107℃).

[0035] Common impurities in lithium battery electrolytes and their corresponding boiling points are as follows: hydrofluoric acid (HF) (boiling point: 19.4℃), ketones (boiling point: 50~150℃), organic acids (boiling point: 50~100℃), aldehydes (boiling point: 20~50℃), and water (boiling point: 100℃).

[0036] When this novel multi-stage condensation distillation and recovery device for electrolyte is in operation, the device is started, inert gas is introduced into the distillation tank 1, and the induced draft fan is turned on until all air is exhausted. The inlet temperature of the heating jacket 103 is set to 150-160℃, and the temperature is heated to the target temperature. The conveyor belt 2 is turned on, and the electrolyte is transported into the distillation tank 1 through the conveyor belt 2. The organic components, hydrofluoric acid (HF), ketones, organic acids, aldehydes, and water in the electrolyte volatilize. The volatilized components are guided by the induced draft fan and enter the condensation device 7 through the discharge pipe 6. The flow rate of the condensate is adjusted so that the temperature range of the primary condensation is 100-130℃. At 0℃, organic components such as DMC and EMC in the steam are condensed and flow out of the liquid outlet pipe 703 at the bottom of the U-shaped working fluid pipe 702 near the beginning to the collection tank 8 for separation. The temperature range of the secondary condensation is 70-100℃, which collects water, organic acids and some ketone compounds. They flow out of the liquid outlet pipe 703 at the bottom of the U-shaped working fluid pipe 702 in the middle to the collection tank 8 for separation. The temperature range of the tertiary condensation is 5-70℃, which collects hydrofluoric acid and aldehyde compounds. They flow out of the liquid outlet pipe 703 at the bottom of the U-shaped working fluid pipe 702 at the end to the final collection tank 801 for separation, and are then absorbed before being discharged.

[0037] In the description of this utility model, it should be noted that the terms "upper", "lower", "inner", "outer", "left", "right", "first", "last", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0038] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," and "connected," etc., should be interpreted broadly. For example, "connected" 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 a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it; although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A multi-stage condensation distillation and recovery device for electrolyte, characterized in that, The distillation tank (1) is arranged horizontally. The side wall of the distillation tank (1) is configured as a sleeve shape including an inner wall (101) and an outer wall (102). A cavity is formed between the inner wall (101) and the outer wall (102). An inner cavity is provided inside the inner wall. A heating sleeve (103) is provided inside the cavity, and a conveyor belt (2) extends laterally through the distillation tank (1) to both sides inside the cavity; Both ends of the distillation tank (1) are provided with sealing plates (104), and the sealing plates (104) are provided with openings (3) for the conveyor belt (2) to pass through; the openings (3) are provided with flexible seals; The distillation tank (1) is provided with an air inlet at one end near the feeding direction, and the air inlet is connected to an inert gas tank (5) through an air inlet pipe (4); The distillation tank (1) is provided with an air outlet at one end near the discharge direction, and the air outlet is connected to the condenser (7) through the discharge pipe (6); An induced draft fan is installed on the discharge pipe (6); The condensation device (7) includes a shell (701), inside which are vertically arranged multiple U-shaped working fluid pipes (702) connected in sequence. The top of the U-shaped working fluid pipe (702) near the first end is connected to the discharge pipe (6) of the distillation tank (1) through an inlet provided at the top of the shell (701); the bottom of the multiple U-shaped working fluid pipes (702) is connected to the corresponding collection tank (8) through liquid discharge pipes (703). The housing (701) has a cooling medium inlet near the bottom and a cooling medium outlet near the top.

2. The multi-stage condensation distillation and recovery device for electrolyte as described in claim 1, characterized in that, Both the air inlet pipe (4) and the discharge pipe (6) are equipped with flow meters and flow regulating switches.

3. The multi-stage condensation distillation and recovery device for electrolyte as described in claim 1, characterized in that, The distillation vessel (1) is equipped with a thermometer to monitor the temperature of the inner cavity.

4. The multi-stage condensation distillation and recovery device for electrolyte as described in claim 1, characterized in that, The heating sleeve (103) is connected to a controller for adjusting the heating temperature.

5. The multi-stage condensation distillation and recovery device for electrolyte as described in claim 1, characterized in that, The collection tank connected to the U-shaped working medium pipe (702) at the end is the end collection tank (801), and the end collection tank (801) is equipped with a tail gas absorbent.

6. The multi-stage condensation distillation and recovery device for electrolyte as described in claim 5, characterized in that, The exhaust gas absorbent comprises a physical adsorbent and a chemical adsorbent arranged in layers.

7. The multi-stage condensation distillation and recovery device for electrolyte as described in claim 6, characterized in that, The physical adsorbent is honeycomb activated carbon.

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