Tail gas recycling device for roller kiln of lithium battery positive electrode material production line

Abstract

The utility model discloses a lithium battery anode material production line roller kiln tail gas recycling device which comprises a gas inlet pipeline connected with a kiln high-temperature tail gas pipeline, the rear end of the gas inlet pipeline is connected with a high-temperature bag-type dust collector, a fresh air part is connected to the side of the gas inlet pipeline, and a high-temperature bag-type dust collector is connected to the rear end of the fresh air part. According to the device, high-temperature tail gas generated by the lithium battery positive electrode material roller kiln is filtered and purified, then the purified high-temperature tail gas is used for spray drying, heat exchange treatment is not needed in the whole process, the heat exchange efficiency is improved, and the energy consumption is reduced. Heat waste caused by heat exchange is avoided, and the heat recycling efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of tail gas treatment of lithium battery positive electrode material production line, in particular to a roller kiln tail gas recycling device for a lithium battery positive electrode material production line. Background Art

[0002] At present, the production process of lithium battery positive electrode materials in the industry generally uses high-temperature solid-phase synthesis for preparation and production. Its production process mainly involves drying and sintering processes, both of which require high temperatures for material processing. Spray drying mainly uses natural gas as a heating source, and its operating temperature is about 200-300°C. With the sharp increase in production capacity in recent years, the corresponding spray drying equipment has also increased, and the demand for natural gas continues to increase. The roller kiln mainly uses electric heating wire heating as a heat source, and its operating temperature is about 700-800°C. When the roller kiln equipment is performing the material sintering process, the exhaust gas generated needs to be treated by an external incinerator, and the exhaust gas generated at about 200°C is directly discharged, resulting in a large loss of heat energy.

[0003] The high-temperature exhaust gas of a common roller kiln is utilized after passing through a shell-and-tube heat exchanger. For example, CN202310276780 provides a kiln exhaust heat energy recovery system, in which the heat energy can be reused after heat exchange. However, this type of structure is limited to the heat exchanger, and its heat exchange efficiency is greatly reduced due to factors such as the logarithmic temperature difference, heat transfer coefficient, heat transfer area, and heat transfer medium. As the use time increases, the accumulation of dirt in the tube and shell of the heat exchanger can also lead to a decrease in heat exchange efficiency. Therefore, how to ensure long-term and stable waste heat recovery and reuse is the primary technical problem. Utility Model Content

[0004] The purpose of the utility model is to provide a roller kiln tail gas recycling device for a lithium battery positive electrode material production line to solve the problems raised in the above background technology.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] A device for recycling exhaust gas from a roller kiln in a lithium battery positive electrode material production line comprises an air intake duct connected to a high-temperature exhaust gas pipeline of the kiln, a high-temperature bag dust collector being connected to the rear end of the air intake duct, a fresh air section being connected to the air intake duct, an outlet end of the high-temperature bag dust collector being connected to an air outlet duct, and an exhaust section being connected to the air outlet duct.

[0007] As a further solution of the utility model: the fresh air part includes a fresh air duct connected to the air inlet duct, and the fresh air duct is provided with a fresh air supply valve.

[0008] As a further solution of the utility model: a temperature sensor is provided on the air intake pipe, and the temperature sensor is in signal communication with a control unit of the fresh air supply valve.

[0009] As a further solution of the utility model: the high-temperature bag dust collector is connected to the air intake duct through a dust removal air intake duct, and the dust removal air intake ducts of the two high-temperature bag dust collectors are respectively provided with a first high-temperature air intake valve and a second high-temperature air intake valve.

[0010] As a further solution of the utility model: the air outlet end of the high-temperature bag dust collector is connected to a high-temperature fan, and a high-temperature air outlet valve is provided between the air inlet end of the high-temperature fan and the high-temperature bag dust collector.

[0011] As a further solution of the utility model: the air inlet end of the high-temperature fan is connected to the air inlet duct through a bypass valve.

[0012] As a further solution of the utility model: the air outlet duct is connected to the air outlet end of the high-temperature fan.

[0013] As a further solution of the utility model: the emptying part includes an emptying pipe connected to the outlet pipe, the emptying pipe is provided with an emergency emptying valve, the outlet pipe is provided with a dust sensor and an exhaust gas conveying valve, the dust sensor, the exhaust gas conveying valve are signal-connected with the control part of the emergency emptying valve.

[0014] As a further solution of the utility model: a high efficiency filter is provided at the end of the air outlet pipe.

[0015] Compared with the prior art, the beneficial effects of the utility model are:

[0016] 1. This application filters and purifies the high-temperature tail gas generated by the roller kiln of lithium battery positive electrode materials, and then uses the purified high-temperature tail gas for spray drying. The whole process does not require heat exchange treatment, which avoids heat waste caused by heat exchange and improves the efficiency of heat reuse;

[0017] 2. This application sets up a fresh air system to control the intake air temperature. The system also sets up a bypass exhaust system to discharge untreated exhaust gas in the event of a system failure to avoid entering the back-end recycling system, thereby ensuring the stability and safety of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the structure of this embodiment;

[0019] In the figure: 1-intake duct, 2-fresh air duct, 3-fresh air supply valve, 4-temperature sensor, 5-first high-temperature intake valve, 6-second high-temperature intake valve, 7-bypass valve, 8-high-temperature bag dust collector, 9-high-temperature outlet valve, 10-high-temperature fan, 11-dust sensor, 12-emergency exhaust valve, 13-exhaust delivery valve, 14-high-efficiency filter, 15-exhaust duct, 16-outlet duct. DETAILED DESCRIPTION

[0020] 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.

[0021] See also Figure 1 In an embodiment of the utility model, a roller kiln exhaust gas recycling device for a lithium battery positive electrode material production line includes an air intake pipe 1 connected to a high-temperature exhaust gas pipeline of the kiln, a high-temperature bag dust collector 8 is connected to the rear end of the air intake pipe 1, and a fresh air section is connected to the air intake pipe 1, the fresh air section includes a fresh air pipe 2 connected to the air intake pipe 1, a fresh air supply valve 3 is provided on the fresh air pipe 2, a temperature sensor 4 is provided on the air intake pipe 1, and the temperature sensor 4 is in signal communication with the control part of the fresh air supply valve 3, two high-temperature bag dust collectors 8 are provided, and the high-temperature bag dust collectors 8 are distributed and connected to the air intake pipe 1 through dust removal air intake pipes, and the dust removal air intake pipes of the two high-temperature bag dust collectors 8 are respectively provided with a first high-temperature air intake valve 5 and a second high-temperature air intake valve 6.

[0022] The air outlet end of the high-temperature bag dust collector 8 is connected to an air outlet pipe 16, and an exhaust part is connected to the air outlet pipe 16. The exhaust part includes an exhaust pipe 15 connected to the air outlet pipe 16, and an emergency exhaust valve 12 is provided on the exhaust pipe 15. A dust sensor 11 and an exhaust gas conveying valve 13 are provided on the air outlet pipe 16. The dust sensor 11, the exhaust gas conveying valve 13 and the control part signal of the emergency exhaust valve 12 are connected. The air outlet end of the high-temperature bag dust collector 8 is connected to a high-temperature fan 10, and the air inlet end of the high-temperature fan 10 is connected to the air inlet pipe 1 through a bypass valve 7. A high-temperature outlet valve 9 is provided between the air inlet end of the high-temperature fan 10 and the high-temperature bag dust collector 8. The air outlet pipe 16 is connected to the air outlet end of the high-temperature fan 10, and a high-efficiency filter 14 is provided at the end of the air outlet pipe 16.

[0023] When the utility model is in use, the high-temperature tail gas of the roller kiln of the lithium battery positive electrode material production line is discharged and enters the recycling device of this embodiment through the air intake pipe 1. A fresh air part is connected to the air intake pipe 1. The opening of the fresh air supply valve 3 is controlled by the temperature sensor 4 in the air intake pipe 1, and the air intake temperature is automatically constant through the air supply volume of the fresh air pipe 2. Then the mixed high-temperature gas enters the high-temperature bag filter 8 through the air intake pipe 1. When the constant temperature tail gas passes through the high-temperature air intake valve 5 and the second high-temperature air intake valve 6 and enters the two high-temperature bag filters 8, the clean tail gas filtered by the high-temperature bag filter 8 is discharged through the high-temperature outlet valve 9 and transported to the outlet pipe 16. The high-temperature bag filter 8 is equipped with an offline pulse backflush system, which can regularly clean the materials attached to the surface of the filter bag. At the same time, the filter bag is equipped with a differential pressure detection to monitor the blockage of the filter bag in real time.

[0024] A high-temperature fan 10 is connected between the outlet pipe 16 and the high-temperature bag filter 8. In addition, a dust sensor 11, an exhaust gas delivery valve 13, and a high-efficiency filter 14 are also provided on the outlet pipe 16. The exhaust part includes an exhaust pipe 15 and an emergency exhaust valve 12. The high-temperature fan 10 is a power device for the air volume in the system, which can pump the exhaust gas of the high-temperature bag filter 8 into the outlet pipe 16. The exhaust gas of the high-temperature bag filter 8 is transported to the high-temperature and high-efficiency filter 14 through the high-temperature fan 10, and the dust content of the exhaust gas is further purified to meet the requirements for spray drying. At the same time, the dust sensor 11 can monitor the dust concentration in the exhaust gas in real time. When it is detected that the current dust concentration exceeds the set value, it is forbidden to introduce the drying equipment. At that time, the PLC controls the exhaust gas delivery valve 13 and the emergency exhaust valve 12 to switch the state, and the exhaust gas is discharged through the exhaust pipe 15, and an alarm is issued at the same time; when the dust concentration is reduced to a safe range, it can be introduced into the drying equipment again. Filter 14 is equipped with differential pressure detection to monitor filter blockage in real time

[0025] In addition, the present embodiment is also provided with an emergency treatment device, which includes a first high-temperature air inlet valve 5, a second high-temperature air inlet valve 6, a bypass valve 7, a high-temperature air outlet valve 9, a high-temperature fan 10, a dust sensor 11, an emergency exhaust valve 12, and an exhaust gas delivery valve 13. When the dust sensor 11 in the system detects an abnormality, the system can automatically close the first high-temperature air inlet valve 5, the second high-temperature air inlet valve 6, the high-temperature air outlet valve 9 and the exhaust gas delivery valve 13, and open the bypass valve 7 and the emergency exhaust valve 12 at the same time, and discharge the gas through the exhaust pipe 15.

[0026] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0027] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains 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.

Claims

1. A roller kiln tail gas recycling device for a lithium battery positive electrode material production line, characterized in that: The invention comprises an air intake pipe (1) connected to a high-temperature tail gas pipeline of a kiln, the rear end of the air intake pipe (1) is connected to a high-temperature bag dust collector (8), the air intake pipe (1) is connected to a fresh air section, the air outlet end of the high-temperature bag dust collector (8) is connected to an air outlet pipe (16), and the air outlet pipe (16) is connected to an emergency exhaust section.

2. The roller kiln tail gas recycling device for a lithium battery positive electrode material production line according to claim 1, characterized in that: The fresh air section comprises a fresh air duct (2) connected to the air inlet duct (1), and a fresh air supply valve (3) is provided on the fresh air duct (2).

3. The roller kiln tail gas recycling device for a lithium battery positive electrode material production line according to claim 2, characterized in that: The air intake pipe (1) is provided with a temperature sensor (4), and the temperature sensor (4) is in signal communication with a control unit of the fresh air supply valve (3).

4. The roller kiln tail gas recycling device for a lithium battery positive electrode material production line according to claim 1, characterized in that: The high-temperature bag dust collector (8) is connected to the air intake duct (1) via a dust removal air intake duct, and the dust removal air intake duct of the high-temperature bag dust collector (8) is provided with a first high-temperature air intake valve (5) and a second high-temperature air intake valve (6).

5. The roller kiln tail gas recycling device for a lithium battery positive electrode material production line according to claim 1, characterized in that: The air outlet end of the high-temperature bag dust collector (8) is connected to a high-temperature fan (10), and a high-temperature air outlet valve (9) is provided between the air inlet end of the high-temperature fan (10) and the high-temperature bag dust collector (8).

6. The roller kiln tail gas recycling device for a lithium battery positive electrode material production line according to claim 5, characterized in that: The air inlet end of the high-temperature fan (10) is connected to the air inlet pipeline (1) via a bypass valve (7).

7. The roller kiln tail gas recycling device for a lithium battery positive electrode material production line according to claim 6, characterized in that: The air outlet pipe (16) is in communication with the air outlet end of the high-temperature blower (10).

8. The roller kiln tail gas recycling device for a lithium battery positive electrode material production line according to claim 1, characterized in that: The exhaust part comprises an exhaust pipe (15) connected to the air outlet pipe (16); an emergency exhaust valve (12) is provided on the exhaust pipe (15); a dust sensor (11) and an exhaust gas delivery valve (13) are provided on the air outlet pipe (16); the dust sensor (11) and the exhaust gas delivery valve (13) are in signal communication with a control unit of the emergency exhaust valve (12).

9. The roller kiln tail gas recycling device for a lithium battery positive electrode material production line according to claim 1, characterized in that: A high efficiency filter (14) is provided at the end of the air outlet pipe (16).

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