Roasting system for waste battery powder

Abstract

The utility model relates to a roasting system for waste battery powder. The roasting system comprises a pneumatic conveying device, a roasting furnace and an indirect heat exchanger which are communicated in sequence, the indirect heat exchanger is provided with a first medium inlet, a first medium outlet, a second medium inlet and a second medium outlet, the first medium inlet and the first medium outlet are communicated with each other, the second medium inlet and the second medium outlet are communicated with each other, and the first medium inlet is communicated with an exhaust port of the roasting furnace; an air inlet of the pneumatic conveying device and an air inlet of the roasting furnace are connected to the second medium outlet in parallel. The roasting system has the advantages of being high in raw material conveying smoothness, low in energy consumption, good in roasting effect, environmentally friendly and the like, and the industrial application prospect is good.

Description

Technical Field

[0001] The utility model relates to a roasting system for waste battery powder, in particular to a roasting system for waste lithium battery powder, and belongs to the field of solid waste resource treatment. Background Art

[0002] Waste lithium battery powder is usually the powdery substance obtained after the waste lithium battery goes through pretreatment processes such as disassembly, crushing, and screening. Its main components include metals or their compounds such as nickel, cobalt, manganese, copper, aluminum, and lithium, water, as well as electrolyte, organic solvent, binder, conductive agent, etc. Roasting of waste lithium battery powder is one of the common processes in the current resource treatment process of waste lithium battery powder. One of the common methods is to heat the waste lithium battery powder with air. After reaching the roasting temperature, the battery powder reacts with oxygen in the air and releases a large amount of heat energy. A large amount of heat is required during the heating process.

[0003] The current situation of battery powder roasting involves the treatment and recycling of retired batteries of new energy vehicles, as well as the development trend of related industries. With the explosive growth of the new energy vehicle market, the first batch of power batteries of new energy vehicles has entered the aging stage, leading to the arrival of the "retirement wave" of power batteries. If these retired power batteries are not properly treated, they will pose a great threat to the environment and safety. Therefore, the recycling of power batteries has become a pain point and hot topic in the current rapid development of the industry.

[0004] The Chinese invention patent specification CN117691230A discloses a pretreatment method and a wet recycling method for waste lithium iron phosphate battery black powder. The pretreatment method includes the following steps: placing the waste lithium iron phosphate battery black powder in a rotary heating furnace and performing roasting treatment in an air atmosphere. After roasting, a roasted material is obtained. The pretreatment method is used for the pretreatment of waste lithium iron phosphate battery black powder before wet recycling. It mainly oxidizes divalent iron in the black powder to trivalent iron by roasting in an air atmosphere, and at the same time removes impurities such as binder and carbon black. Thus, although no oxidant and organic solvent are needed during subsequent wet recycling, greatly reducing the amount of waste liquid, its roasting temperature reaches 600 - 800 °C. During the roasting process, organic substances such as binder and electrolyte are prone to react under high temperature conditions to generate toxic and harmful gases such as dioxin and hydrogen fluoride, increasing the burden and cost of subsequent tail gas treatment. In addition, this patent application does not consider how to convey materials into the rotary heating furnace, nor does it consider how to save treatment energy consumption, and there are problems such as low energy utilization rate. Content of the Utility Model

[0005] Aiming at the deficiencies of the prior art, the purpose of the utility model is to provide a roasting system for waste battery powder with low energy consumption.

[0006] To solve the above technical problems, the technical solution of the present utility model is as follows:

[0007] A roasting system for waste battery powder, comprising a pneumatic conveying device, a roasting furnace and an indirect heat exchanger connected in sequence; the indirect heat exchanger has a first medium inlet, a first medium outlet, a second medium inlet and a second medium outlet, the first medium inlet and the first medium outlet are interconnected, the second medium inlet and the second medium outlet are interconnected, the first medium inlet is connected to the exhaust port of the roasting furnace, and the air inlet of the pneumatic conveying device and the air inlet of the roasting furnace are connected in parallel to the second medium outlet.

[0008] In this way, the high-temperature flue gas generated during the air roasting process of the waste battery powder in the roasting furnace can exchange heat with the air input through the second medium inlet in the indirect heat exchanger to cool the high-temperature flue gas, facilitating subsequent treatment and emission; at the same time, a part of the generated hot air enters the pneumatic conveying device as the working medium for pneumatic conveying. Meanwhile, the hot air disperses and heats the waste battery powder during the pneumatic conveying process. Subsequently, the waste battery powder can be input into the roasting furnace to carry out an air roasting reaction with another part of the hot air, completing the roasting process more quickly. Thus, the recycling of the high-temperature flue gas generated by roasting can be realized, which is beneficial to reducing energy consumption; at the same time, the waste battery powder has been preliminarily heated and dispersed before entering the roasting furnace and contacts and mixes with the hot air in the roasting furnace, which is conducive to the more efficient and thorough progress of the roasting reaction.

[0009] In waste battery powder treatment enterprises, the raw material workshop for storing waste battery powder and the roasting workshop usually have a certain distance, and the waste battery powder is in powder form, so it is not suitable to be transferred and conveyed by a conveyor belt, nor is it suitable for manual transfer by a feeding trolley. The present utility model can effectively solve the problems of transfer and transportation of waste battery powder between different workshops through the setting of the pneumatic conveying device, and will not cause dust pollution, and the efficiency is also relatively high. Through the setting of the pneumatic conveying device and with the help of the hot air produced by the indirect heat exchanger, the present utility model not only realizes the pneumatic conveying of the waste battery powder, but also pre-heats the waste battery powder, which helps to ensure the smoothness of the pneumatic conveying and improve the subsequent roasting efficiency and roasting sufficiency. In addition, it can reduce the possibility of clogging pipelines and other components during the transportation of the waste battery powder to the roasting furnace, and there is no need for gas-solid separation during the preheating process. The equipment and operation are simple and efficient, and the failure rate is low.

[0010] Further, the pneumatic conveying device includes a gas-solid mixer, a conveying pipe and a gas-solid separator connected in sequence. The gas-solid mixer is provided with a first inlet, an air inlet connected to the second medium outlet and a first outlet connected to the conveying pipe. A first fan is provided at the exhaust port of the gas-solid separator, and the feed port of the roasting furnace is connected to the discharge port of the gas-solid separator through a feeding mechanism.

[0011] Furthermore, the pneumatic conveying device further includes at least one disturbance enhancement component disposed on the conveying pipe. The disturbance enhancement component includes a first cylinder body, a rotating shaft disposed within the first cylinder body, a second inlet and a second outlet disposed on the first cylinder body, and a driving mechanism drivingly connected to the rotating shaft. The rotating shaft extends along the length direction of the first cylinder body, and a plurality of paddle blades are provided on the rotating shaft. The plurality of paddle blades are sequentially distributed along the length direction of the rotating shaft. The second inlet is communicated with the first outlet, and the inlet of the gas-solid separator is communicated with the second outlet. The rotation speed of the rotating shaft can be controlled by the driving mechanism as required.

[0012] Thus, a part of the hot air generated by the indirect heat exchanger enters the gas-solid mixer. The hot air is preliminarily mixed and preheated with the waste battery powder in the gas-solid mixer, so that the waste battery powder is suspended in the hot air to form a gas-solid rough mixture. Subsequently, the gas-solid rough mixture enters the disturbance enhancement component, and the plurality of paddle blades sequentially distributed along the length direction of the rotating shaft strongly disturb the gas-solid rough mixture, enhancing the turbulence intensity of the gas-solid rough mixture. The coarse particles of the waste battery powder are further repeatedly broken up, exposing new surfaces, which can effectively promote the volatilization and separation of organic matters such as residual electrolyte and binder and / or moisture in the waste battery powder, and then obtain fine waste battery powder with good fluidity, low organic matter content and not easy to agglomerate, effectively improving the smoothness of pneumatic conveying and reducing the possibility of blocking components such as pipelines during the transportation of the waste battery powder to the roasting furnace. In addition, during the process of the feeding mechanism transporting the fine waste battery powder to the roasting furnace, there is no need to worry about the agglomeration or caking of the waste battery powder due to extrusion or other effects, which may affect the subsequent roasting effect. During roasting, the preheated and fully broken-up fine waste battery powder and hot air are simultaneously input into the roasting furnace. The fine waste battery powder and hot air only need to absorb a small amount of heat to quickly reach the temperature required for the roasting reaction, which helps to reduce the required heating time and heating energy consumption, thus effectively saving energy, realizing the recycling of heat and improving the energy utilization rate. Moreover, the particle size of the input fine waste battery powder has been further refined and the amount of organic matter contained therein is quite low, so that the fine waste battery powder and the active substances contained therein can be more fully contacted with the hot air, and the situation of competitive reaction between the organic matter and the air is greatly reduced, thereby making the roasting reaction more efficient and thorough, and effectively improving the roasting efficiency and roasting adequacy, and obtaining a better roasting effect. In addition, the roasting reaction stage is a high-temperature reaction stage. Since the amount of organic matter contained in the fine waste battery powder is quite low, the possibility of generating toxic and harmful gases such as fluorides, nitrogen oxides, and dioxins due to the oxidation combustion reaction of the organic matter in this stage is greatly reduced, effectively reducing the amount of toxic and harmful gases in the high-temperature flue gas. Therefore, it is more environmentally friendly and can also greatly reduce the burden and cost of subsequent tail gas treatment.

[0013] It can be seen that the utility model exchanges heat between high-temperature flue gas and air through an indirect heat exchanger, and uses part of the hot air for pneumatic conveying and pretreatment of waste battery powder, and uses part of the hot air for air calcination treatment. This can improve the smoothness of the conveying of waste battery powder, and better solve the problem of raw material conveying faced in the industrial treatment process. At the same time, it better realizes the recycling of heat, which is beneficial to energy conservation and consumption reduction. In addition, the air calcination effect of waste battery powder is better, and the generation amount of toxic and harmful gases is lower. Therefore, the industrial application prospect of the calcination system of the utility model is good, which helps to better realize the industrial calcination treatment of waste battery powder.

[0014] As another embodiment, the pneumatic conveying device includes a bin assembly, a conveying pipe and a gas-solid separator. The bin assembly and the second medium outlet are connected in parallel to the inlet end of the conveying pipe, and the outlet end of the conveying pipe is communicated with the gas-solid separator. A first fan is provided at the exhaust port of the gas-solid separator, and the feed port of the roasting furnace is communicated with the discharge port of the gas-solid separator through a feeding mechanism. At least one disturbance enhancement component is provided on the conveying pipe. The disturbance enhancement component includes a first cylinder body, a rotating shaft arranged in the first cylinder body, a second inlet and a second outlet arranged on the first cylinder body, and a driving mechanism drivingly connected with the rotating shaft. The rotating shaft extends along the length direction of the first cylinder body, and a plurality of paddle blades are arranged on the rotating shaft. The plurality of paddle blades are sequentially distributed along the length direction of the rotating shaft. The second inlet is communicated with the inlet end of the conveying pipe, and the inlet of the gas-solid separator is communicated with the second outlet. Thus, a disturbance enhancement component is arranged in the pneumatic conveying device to disperse the waste battery powder and promote mass transfer and heat transfer.

[0015] Further, the second inlet is located at or near one end of the first cylinder body, and the second outlet is located at or near the other end of the first cylinder body. In this way, the residence time of the material in the first cylinder body and the collision frequency with components such as paddle blades can be ensured, and thus a good dispersion and homogenization effect can be ensured.

[0016] Further, the included angle between the axis of the first cylinder body and the horizontal plane is 45-90°.

[0017] Further, the position where the second outlet is located is higher than the position where the second inlet is located.

[0018] Further, the gas-solid mixer includes a second cylinder body. The second cylinder body has an inlet end and an outlet end distributed along the axial direction. The first inlet, the air inlet and the first outlet are all arranged on the second cylinder body. The first inlet is located at or near the inlet end of the second cylinder body, the air inlet is located at or near the inlet end of the second cylinder body, and the first outlet is located at or near the outlet end of the second cylinder body.

[0019] Further, the included angle between the axis of the second cylinder body and the horizontal plane is 0-30°.

[0020] Furthermore, the position of the first outlet is higher than that of the first inlet. In this way, the fully dispersed materials can be smoothly transported, while the caked materials or the materials with relatively large particle sizes stay at the front end of the gas-solid mixture or in the middle and lower parts of the first cylinder due to their own gravity, and can be transported to the downstream side only after continuous air flow disturbance and mechanical dispersion.

[0021] Furthermore, the paddle includes at least two blades, preferably three blades; the at least two blades are evenly distributed along the circumferential direction of the rotating shaft;

[0022] Preferably, the blades of the axially adjacent paddles are arranged in an interleaved manner. In this way, the turbulence degree and the flow path of the material flow in the disturbance enhancement component can be further improved, and the collision and contact opportunities between the powder and the blades can be further increased, thereby further improving the heating and the volatilization and separation effects of the organic matter;

[0023] Preferably, the blades are inclined along the circumferential direction of the rotating shaft, so that the included angle between the width direction of the blades and the cross section of the first cylinder is 30-60°. In this way, while ensuring the disturbance effect, when the rotating shaft drives the paddles to rotate, the effective suction force is increased, the material flows more smoothly in the disturbance enhancement component, and at the same time, the battery powder is prevented from accumulating at the blades.

[0024] Furthermore, the second medium outlet is connected in parallel with a first valve, a second valve and a third valve. The rotating shaft is a hollow tube. The outlet of the third valve is rotatably communicated with one end of the rotating shaft, and the other end of the rotating shaft is sealed; the blade has a cavity, the cavity is communicated with the rotating shaft, and a plurality of air holes communicated with the cavity are opened on the blade. Thus, hot air enters the rotating shaft and flows out through the air holes on the blade. On the one hand, the temperature of the high heat-conducting components such as the rotating shaft and the paddle can be increased, and solid-solid heat transfer is realized through the collision and contact between the material and the blade components, so as to realize more sufficient heating of the waste battery powder and further improve the volatilization and separation effects of organic matters such as binders and electrolytes. On the other hand, when the hot air jets out from the air holes on the blade, it will form an impact on the material flow in the disturbance enhancement component in another dimension, further increasing its flow turbulence degree, helping to make full use of the energy in the air to improve the dispersion and heating effects, further promoting the separation of the organic matter, and fully preparing for the next stage of roasting. In addition, the hot air introduced through the third valve can dilute the original gas-solid mixture, reduce the concentration of volatile substances in the gas phase, and reduce its partial pressure, which helps the volatile substances in the waste battery powder to volatilize more fully.

[0025] Hot air performs classification dispersion and classification preheating on waste battery powder in two stages. Among them, the material can be further preheated to a higher temperature (200 - 300 °C) in the disturbance enhancement component. Through the cooperation of the gas-solid mixer and the disturbance enhancement component, the mass transfer, heat transfer and reaction effects are effectively synergistically optimized, promoting the volatilization and separation of organic matter to be concentrated and fully carried out in the disturbance enhancement component, and directly sent to the tail gas treatment device after being separated by the gas-solid separator, effectively reducing the erosion and blockage of other equipment. During roasting, the pre-classified and fully dispersed waste battery fine powder and hot primary air are simultaneously input into the roasting furnace. The waste battery fine powder and hot air only need to absorb a small amount of heat to quickly reach the temperature required for the roasting reaction, which helps to reduce the required heating time and heating energy consumption, thus effectively saving energy, realizing the recycling of heat and improving the energy utilization rate.

[0026] Furthermore, at least one of the inner wall of the first cylinder, the rotating shaft, and the paddle is made of a heat-conducting material, and the heat-conducting material is one of magnesium alloy, aluminum alloy, steel, and copper alloy. Thus, the above-mentioned related components have good heat-conducting and heat-storing capabilities. During operation, their temperatures rise rapidly, enabling the waste battery powder to not only exchange heat with hot air but also undergo multiple and continuous solid-solid interface conduction heating during collisions and contacts with them, enhancing the heating effect, more effectively promoting the separation between the residual electrolyte, binder, and active substances in the waste battery powder, and promoting the full exposure of the roasting reaction interface and heat transfer interface of the waste battery powder, further optimizing the conveying, pretreatment, and roasting effects.

[0027] Furthermore, the second medium outlet is connected in parallel with a first valve and a second valve. The outlet of the first valve is connected to the inlet of the pneumatic conveying device, and the outlet of the second valve is connected to the inlet of the roasting furnace.

[0028] Furthermore, the number of disturbance enhancement components is at least 2. The gas-solid mixer, each disturbance enhancement component, and the gas-solid separator are connected in series in sequence, or each disturbance enhancement component is connected in parallel between the gas-solid mixer and the gas-solid separator. In this way, through the parallel or series setting of multiple disturbance enhancement components, the preheating, dispersion, and pyrolysis effects can be improved, or the feeding flow rate can be strengthened, the processing efficiency can be increased, and the smooth operation of the system can be ensured. In addition, the inclination angles of different disturbance enhancement components can be set separately. For example, some disturbance enhancement components are set vertically, and some disturbance enhancement components are set horizontally to further enhance the disturbance effect.

[0029] Preferably, the gas-solid mixer is a centrifugal stirring mixer.

[0030] Further, it further includes a transition bin communicated with the discharge port of the gas-solid separator. A third outlet is provided at the bottom of the transition bin, and the third outlet is communicated with the inlet of the feeding mechanism through a fourth valve; preferably, the feeding mechanism is a screw feeding mechanism. In this way, it can play a buffering role and block the discharge port of the gas-solid separator, so that the gas in the gas-solid separator flows to its exhaust port and prevents the gas in the roasting furnace from entering the gas-solid separator.

[0031] Further, the roasting furnace is a rotary heating furnace. The rotary heating furnace is suitable for continuous feeding and continuous discharging to achieve continuous roasting treatment. It can be combined with functional units such as a gas-solid mixer, a disturbance enhancement component, a gas-solid separator, and an indirect heat exchanger to form a continuous treatment type roasting system with continuous feeding and continuous discharging, improving the treatment efficiency and better meeting industrial applications.

[0032] Preferably, the rotary heating furnace includes a rotary cylinder assembly and a discharge hood rotatably connected to the discharge end of the rotary cylinder assembly. The air inlet of the roasting furnace is arranged at the feeding end of the rotary cylinder assembly; a roasted material outlet is provided at the bottom of the discharge hood, and the top of the discharge hood is communicated with the first medium inlet. Further, the feeding mechanism is communicated with the feeding end of the rotary cylinder assembly.

[0033] Optionally, the battery is an alkali metal battery. Further, the alkali metal battery includes one or several of a lithium battery and a sodium battery.

[0034] The main steps of roasting using the roasting system as described above are as follows:

[0035] S1. Start the roasting furnace. At the same time, continuously input air through the second medium inlet and open the second valve (6.4) so that the air is heated.

[0036] S2. After the target temperature is reached in the roasting furnace, input the waste battery powder to be processed into the pneumatic conveying device; at the same time, make a part of the hot air output from the second medium outlet enter the pneumatic conveying device. After being dispersed and mixed, a gas-solid mixture is obtained.

[0037] S3. The gas-solid mixture is subjected to gas-solid separation at the end of the pneumatic conveying device to obtain hot battery powder and tail gas.

[0038] S4. Input the hot battery powder into the roasting furnace through the feeding mechanism, and at the same time input a part of the hot air output from the second medium outlet into the roasting furnace. A large amount of heat energy is released after the waste battery powder is roasted with air. After roasting, roasted material and high-temperature flue gas are obtained.

[0039] S5. Input the high-temperature flue gas into the indirect heat exchanger through the first medium inlet, indirectly exchange heat with the air input through the second medium inlet, obtain low-temperature flue gas at the first medium outlet, and obtain hot air at the second medium outlet;

[0040] S6. Repeat S2 - S5 until the roasting treatment of all the waste battery powder to be processed is completed.

[0041] The single structure of the roasting system of the present utility model is simple and the overall layout is reasonable. On the one hand, it can greatly reduce the equipment procurement, operation and maintenance costs, and has a wide range of raw material applicability, being applicable to various powders such as powders with impurities, wet powders, and caked powders. On the other hand, it can fully recover a large amount of heat energy generated during the roasting process, exchange the heat released by the roasting reaction through the indirect heat exchanger to obtain high-temperature hot air. A part of the exchanged hot air is used for the pneumatic conveying of the waste battery powder, and during the pneumatic conveying process of the waste battery powder, the material preheating, dispersion are realized step by step, and the heating, particle refinement, and separation and removal of volatile organic matters of the waste battery powder are directly realized simultaneously in the disturbance enhancement section, making full preparations for the subsequent roasting, effectively avoiding the phenomena of roasting material agglomeration and roasting furnace ring formation caused by too high local temperature difference of the roasting material, optimizing the roasting operation process. At the same time, harmful gases can be collected and treated efficiently with a short process, reducing the erosion of the roasting system, and helping to improve the service life of the roasting system or related components. Another part of the exchanged high-temperature hot air is introduced into the roasting furnace for roasting the waste battery powder. Thus, the energy utilization rate can be effectively improved, the energy consumption can be reduced, and the defects of only being able to recycle part of the heat and low heat utilization rate in the prior art can be overcome. Additionally, more preferably, the material is conveyed through gas paths in multiple directions in sequence, such as horizontal gas path conveying and vertical gas path conveying, which can fully ensure that the material entering the gas-solid separator is fully dispersed, and mechanical and air flow collaborative preheating and dispersion are carried out during the conveying process, effectively avoiding the problem of conveying blockage, with low raw material requirements and wide applicability. In addition, through the cooperation of the transition bin and the feeding mechanism (especially the screw feeding mechanism), physical airtight blocking is realized, and air path blocking can be realized through a simple structure.

[0042] Compared with the prior art, the roasting system of the present utility model has many advantages such as high smoothness of raw material conveying, high energy utilization rate, low energy consumption, good roasting effect, environmental friendliness, etc., and has a wide range of raw material applicability, being applicable to various powders such as powders with impurities, wet powders, and caked powders, with good industrial application prospects, and is helpful to better realize the industrial roasting treatment of waste battery powder. Brief Description of the Drawings

[0043] Figure 1 is a structural schematic diagram of the roasting system of Embodiment 1 of the present utility model.

[0044] Figure 2 is a structural schematic diagram of the disturbance enhancement component of Embodiment 2 of the present utility model.

[0045] Figure 3 It is a three-dimensional internal structure diagram of the disturbance enhancement component of Embodiment 2 of the present utility model.

[0046] Figure 4 It is a three-dimensional diagram of the rotating shaft and the paddle blades of Embodiment 2 of the present utility model.

[0047] Figure 5 It is a schematic structural diagram of the roasting system of Embodiment 2 of the present utility model.

[0048] Figure 6 It is a schematic structural diagram of the roasting system of Embodiment 8 of the present utility model.

[0049] Figure 7 It is a three-dimensional diagram of the disturbance enhancement component of Embodiment 8 of the present utility model.

[0050] Figure 8 It is a three-dimensional diagram of the rotating shaft and the paddle blades of Embodiment 8 of the present utility model.

[0051] Figure 9 It is a sectional view of the rotating shaft and the paddle blades of Embodiment 8 of the present utility model.

[0052] Figure 10 It is a schematic structural diagram of the roasting system of Embodiment 10 of the present utility model. Detailed implementation manners

[0053] The present utility model will be described in detail below in conjunction with embodiments. It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other. For the sake of convenience of description, words such as "upper", "lower", "left", and "right" in the following text only represent the same directions as the upper, lower, left, and right directions of the drawings themselves, and do not limit the structure.

[0054] Embodiment 1

[0055] See Figure 1 , a roasting system for waste battery powder, including a silo assembly 1, a pneumatic conveying device 2, a roasting furnace 3, an indirect heat exchanger 6, and an exhaust gas treatment system 8. The pneumatic conveying device 2 includes a gas-solid mixer 2.6, a conveying pipe 2.8, and a gas-solid separator 2.1 that are connected in sequence;

[0056] The silo assembly 1 includes a silo body 1.1 for temporarily storing waste battery powder, and a first level gauge 1.2 for monitoring the material level height is provided inside the silo body;

[0057] The gas-solid mixer 2.6 is provided with a first inlet 2.61, an air inlet 2.62, a first outlet 2.63 and a stirring mechanism arranged inside the gas-solid mixer; the bottom of the silo body is communicated with the first inlet 2.61 through a fifth valve 1.3 (rotary seal valve, which is convenient for realizing quantitative feeding); at this time, the roasting system is more suitable for roasting and processing waste battery powder with higher purity and more uniform fineness.

[0058] The inlet of the gas-solid separator 2.1 is communicated with the second outlet 2.75 through a conveying pipe. The exhaust port of the gas-solid separator 2.1 is provided with a first fan 2.2 (high-pressure fan), and the outlet of the first fan 2.2 is communicated with the tail gas treatment system 8 so as to treat the heat-exchanged air; the gas-solid separator 2.1 is a bag filter.

[0059] The indirect heat exchanger 6 has a first medium inlet, a first medium outlet, a second medium inlet and a second medium outlet. The first medium inlet and the first medium outlet are communicated with each other, the second medium inlet and the second medium outlet are communicated with each other. The first medium inlet is communicated with the exhaust port of the roasting furnace 3, and the first medium outlet is communicated with the tail gas treatment system 8 through a second fan 7; the second medium inlet is provided with a third fan 6.3, and the second medium outlet is communicated with a fourth valve 6.2 (ventilation butterfly valve). The outlet of the fourth valve 6.2 is connected in parallel with a first valve 6.5 (ventilation butterfly valve) and a second valve 6.4 (ventilation butterfly valve). The outlet of the first valve 6.5 is communicated with the air inlet 2.62 of the gas-solid mixer 2.6, and the outlet of the second valve 6.4 is communicated with the air inlet of the roasting furnace 3.

[0060] Embodiment 2

[0061] See Figures 2-5 , in addition to having the same structure as Embodiment 1, this embodiment further includes a disturbance enhancement component 2.7 arranged on the conveying pipe 2.8. The disturbance enhancement component 2.7 includes a vertically arranged first cylinder body 2.71, a rotating shaft 2.72 arranged inside the first cylinder body 2.71, a second inlet 2.74 and a second outlet 2.75 arranged on the first cylinder body 2.71 and a driving mechanism drivingly connected with the rotating shaft. The rotating shaft 2.72 extends along the length direction of the first cylinder body 2.71, and a plurality of paddle blades 2.73 are arranged on the rotating shaft 2.72. The plurality of paddle blades 2.73 are sequentially and evenly distributed along the length direction of the rotating shaft 2.72; the second inlet 2.74 is communicated with the first outlet 2.63 through a conveying pipe; the second inlet 2.74 is located on the side wall at one end (lower end) of the first cylinder body, and the second outlet 2.75 is located on the side wall at the other end (upper end) of the first cylinder body.

[0062] Embodiment 3

[0063] In addition to having the same structure as Embodiment 2, the gas-solid mixer 2.6 includes a second cylinder body and a stirring mechanism disposed within the second cylinder body. The second cylinder body has an inlet end and an outlet end distributed along the axial direction. The first inlet 2.61, the air inlet 2.62, and the first outlet 2.63 are all disposed on the second cylinder body. The first inlet 2.61 and the air inlet 2.61 are located at or near the inlet end of the second cylinder body, and the first outlet 2.63 is located at or near the outlet end of the second cylinder body. The axial direction of the second cylinder body forms an angle of 0° with the horizontal plane, and the position of the first outlet 2.63 is higher than the position of the first inlet 2.61. The stirring mechanism includes a stirring shaft extending along the axial direction of the second cylinder body and a plurality of dispersion vanes disposed on the stirring shaft and arranged axially.

[0064] Embodiment 4

[0065] In addition to having the same structure as Embodiment 1, the paddle 2.73 includes 3 blades; the 3 blades are evenly distributed circumferentially along the rotating shaft 2.72; the blades of adjacent paddles 2.73 are arranged in an interleaved manner; the blades are inclined circumferentially along the rotating shaft 2.72 such that the angle between the blades and the cross-section of the first cylinder body 2.71 (the section perpendicular to the central axis of the first cylinder body) is 45°. The inner wall of the first cylinder body 2.71, the rotating shaft 2.72, and the paddle 2.73 are all made of steel.

[0066] Embodiment 5

[0067] In addition to having the same structure as Embodiment 1, it further includes a transition bin 2.4 communicated with the discharge port of the gas-solid separator 2.1. A second level gauge 2.3 is provided in the transition bin 2.4 to monitor the material level height in the transition bin, ensure a good seal formed by the transition bin 2.4 and the material, prevent the gas containing organic volatiles and separation substances from permeating into the roasting furnace, and also prevent the gas in the roasting furnace from reversely permeating into the gas-solid separator; a third outlet is provided at the bottom of the transition bin 2.4, and the third outlet is communicated with the inlet of the feeding mechanism 3.1 through a fourth valve 2.5 (rotary seal valve); the feeding mechanism 3.1 is a screw feeding mechanism, and the inlet of the roasting furnace 3 is communicated with the discharge port of the gas-solid separator 2.1 through the feeding mechanism 3.1.

[0068] Embodiment 6

[0069] In addition to having the same structure as Embodiment 1, the roasting furnace 3 in this embodiment is a rotary heating furnace, which includes a rotary cylinder assembly 3.2 and a discharge hood 3.4 rotatably connected to the discharge end of the rotary cylinder assembly 3.2. The feeding mechanism 3.1 and the second valve 6.4 are both communicated with the feeding end of the rotary cylinder assembly 3.2. A roasting material outlet is provided at the bottom of the discharge hood 3.4, and the roasting material outlet is communicated with a cooling device 3.6 through a sixth valve (rotary seal valve) 3.5 to cool down the roasting material. The top of the discharge hood 3.4 is communicated with the first medium inlet. The rotary cylinder assembly 3.2 is made of steel and has a heating module 3.3 to heat the materials inside the rotary cylinder assembly.

[0070] Embodiment 7

[0071] In addition to having the same structure as Embodiment 1, a dust removal mechanism is provided between the first medium inlet and the exhaust port of the roasting furnace 3 to remove dust particles contained in the high-temperature flue gas. The dust removal mechanism includes a cyclone dust collector 4 and a high-temperature dust collector 5. The exhaust port of the roasting furnace 3, the cyclone dust collector 4, the high-temperature dust collector 5, and the first medium inlet are communicated in sequence. The discharge ports of the cyclone dust collector 4 and the high-temperature dust collector 5 are both communicated with the cooling device 3.6.

[0072] Optionally, the high-temperature dust collector is an existing high-temperature resistant dust collector, such as the high-temperature dust collector described in prior arts such as CN101559307A and CN110743265B.

[0073] Embodiment 8

[0074] Repeat Embodiment 2, with the main difference being: Refer to Figures 6-9 , the second medium outlet is connected in parallel with a first valve 6.5 (ventilation butterfly valve), a second valve 6.4 (ventilation butterfly valve), and a third valve 6.6 (ventilation butterfly valve). The rotating shaft 2.72 is a hollow tube. The outlet of the third valve 6.6 is rotatably communicated with one end of the rotating shaft 2.72 through a rotary joint, and the other end of the rotating shaft 2.72 is sealed. The blade has a cavity 2.732, the cavity is communicated with the rotating shaft 2.72, and a plurality of air holes 2.731 communicated with the cavity are opened on the blade. Air holes are provided on both the upper surface and the lower surface of the blade. Optionally, as another implementation, air holes are provided on both the upper surface and the end surface of the blade.

[0075] Embodiment 9

[0076] Repeat Embodiment 8, with the main difference being: From the second inlet 2.74 to the second outlet 2.75, the number of air holes on the blades of each paddle 2.73 gradually increases.

[0077] Embodiment 10

[0078] Repeat Example 2, with the main differences being: Refer to Figure 10 , the pneumatic conveying device 2 is not provided with a gas-solid mixer, the outlet of the silo assembly 1 and the second medium outlet are connected in parallel to the inlet end of the conveying pipe 2.8, and the outlet end of the conveying pipe 2.8 is communicated with the gas-solid separator 2.1.

[0079] Example 11

[0080] Repeat Example 1, with the main differences being: the pneumatic conveying device 2 is not provided with a gas-solid mixer, the outlet of the silo assembly 1 and the second medium outlet are connected in parallel to the inlet end of the conveying pipe 2.8, and the outlet end of the conveying pipe 2.8 is communicated with the gas-solid separator 2.1.

[0081] Example 12

[0082] Repeat Example 1, with the main differences being: the position of the first outlet is higher than the position of the first inlet, the axial direction of the second cylinder forms an angle of 15° with the horizontal plane; the axial direction of the first cylinder forms an angle of 75° with the horizontal plane.

[0083] Example 13

[0084] Repeat Example 2, with the main differences being: the number of disturbance enhancement components is 3; the gas-solid mixer, each disturbance enhancement component, and the gas-solid separator are connected in series in sequence.

[0085] Example 14

[0086] Repeat Example 2, with the main differences being: the number of disturbance enhancement components is 3, and each disturbance enhancement component is connected in parallel between the gas-solid mixer and the gas-solid separator.

[0087] The content clarified in the above embodiments should be understood that these embodiments are only used to illustrate the present invention more clearly, rather than to limit the scope of the present invention. After reading the present invention, various equivalent forms of modification made by those skilled in the art to the present invention all fall within the scope defined by the appended claims of this application.

Claims

1. A system for roasting waste battery powder, characterized in that: The invention comprises a pneumatic conveying device (2), a roasting furnace (3) and an indirect heat exchanger (6) which are connected in sequence; the indirect heat exchanger (6) has a first medium inlet, a first medium outlet, a second medium inlet and a second medium outlet; the first medium inlet and the first medium outlet are connected to each other; the second medium inlet and the second medium outlet are connected to each other; the first medium inlet is connected to the exhaust port of the roasting furnace (3); the air inlet of the pneumatic conveying device (2) and the air inlet of the roasting furnace (3) are connected to the second medium outlet.

2. The roasting system according to claim 1, characterized in that: The pneumatic conveying device (2) comprises a gas-solid mixer (2.6), a conveying pipe (2.8) and a gas-solid separator (2.1) which are connected in sequence; the gas-solid mixer (2.6) is provided with a first inlet (2.61), an air inlet (2.62) connected to a second medium outlet and a first outlet (2.63) connected to the conveying pipe (2.8); the feed inlet of the roasting furnace (3) is connected to the discharge outlet of the gas-solid separator (2.1) via a feeding mechanism (3.1).

3. The roasting system according to claim 2, characterized in that: The pneumatic conveying device (2) further comprises at least one disturbance enhancement component (2.7) arranged on the conveying pipe (2.8), the disturbance enhancement component (2.7) comprising a first cylinder (2.71), a rotating shaft (2.72) arranged in the first cylinder (2.71), a second inlet (2.74) and a second outlet (2.75) arranged on the first cylinder (2.71), and a driving mechanism connected to the rotating shaft in a transmission manner, the rotating shaft (2.72) extending along the length direction of the first cylinder (2.71), the rotating shaft (2.72) being provided with a plurality of blades (2.73), the plurality of blades (2.73) being distributed in sequence along the length direction of the rotating shaft (2.72); the second inlet (2.74) being connected to the first outlet (2.63), and the inlet of the gas-solid separator (2.1) being connected to the second outlet (2.75).

4. The roasting system according to claim 1, characterized in that: The pneumatic conveying device (2) comprises a silo assembly (1), a conveying pipe (2.8) and a gas-solid separator (2.1); the silo assembly (1) and the second medium outlet are connected to the inlet end of the conveying pipe (2.8); the outlet end of the conveying pipe (2.8) is connected to the gas-solid separator (2.1); the feed inlet of the roasting furnace (3) is connected to the discharge port of the gas-solid separator (2.1) via a feeding mechanism (3.1); at least one disturbance enhancement component (2.7) is provided on the conveying pipe (2.8); the disturbance enhancement component (2.7) comprises a first cylinder (2.71), a first cylinder (2.71) and a second cylinder (2.71) arranged on the first cylinder (2. The invention relates to a gas-solid separator (2.1) comprising a rotating shaft (2.72) in a first cylinder (2.71), a second inlet (2.74) and a second outlet (2.75) arranged on the first cylinder (2.71), and a driving mechanism connected to the rotating shaft in a transmission manner, wherein the rotating shaft (2.72) extends along the length direction of the first cylinder (2.71), and a plurality of paddles (2.73) are arranged on the rotating shaft (2.72), and the plurality of paddles (2.73) are distributed in sequence along the length direction of the rotating shaft (2.72); the second inlet (2.74) is connected to the inlet end of the conveying pipe (2.8), and the inlet of the gas-solid separator (2.1) is connected to the second outlet (2.75).

5. The roasting system according to claim 3 or 4, characterized in that: The blade (2.73) comprises at least two blades, and the at least two blades are evenly distributed along the circumference of the rotating shaft (2.72); and / or the second inlet (2.74) is located at or near one end of the first cylinder (2.71), and the second outlet (2.75) is located at or near the other end of the first cylinder (2.71), and the angle between the axial direction of the first cylinder (2.71) and the horizontal plane is 45-90 degrees.

6. The roasting system according to claim 5, characterized in that: The second medium outlet is connected to a first valve (6.5), a second valve (6.4) and a third valve (6.6); the outlet of the first valve (6.5) is connected to the air inlet of the pneumatic conveying device (2); the outlet of the second valve (6.4) is connected to the air inlet of the roasting furnace (3); the rotating shaft (2.71) is a hollow tube; the outlet of the third valve (6.6) is rotatably connected to one end of the rotating shaft (2.71); and the other end of the rotating shaft (2.71) is sealed; the blade has a cavity, which is connected to the rotating shaft (2.71); and a plurality of air holes connected to the cavity are provided on the blade.

7. The roasting system according to claim 3, characterized in that: At least one of the inner wall of the first cylinder (2.71), the rotating shaft (2.72), and the blade (2.73) is made of a heat-conducting material, and the heat-conducting material is one of a magnesium alloy, an aluminum alloy, steel, and a copper alloy; and / or, the gas-solid mixer (2.6) comprises a second cylinder, the second cylinder has an inlet end and an outlet end distributed along the axial direction, the first inlet (2.61), the air inlet (2.62), and the first outlet (2.63) are all arranged on the second cylinder, the first inlet (2.61) and the air inlet (2.61) are located at or near the inlet end of the second cylinder, the first outlet (2.63) is located at or near the outlet end of the second cylinder, the angle between the axial direction of the second cylinder and the horizontal plane is 0-30°, and the position of the first outlet (2.63) is higher than the position of the first inlet (2.61).

8. The roasting system according to claim 3 or 4, characterized in that: The number of disturbance enhancement components (2.7) is at least two, and the gas-solid mixer (2.6), each disturbance enhancement component (2.7), and the gas-solid separator (2.1) are connected in series in sequence, or each disturbance enhancement component (2.7) is connected in parallel between the gas-solid mixer (2.6) and the gas-solid separator (2.1).

9. The roasting system according to any one of claims 2 to 4, characterized in that: It also comprises a transition bin (2.4) connected to the discharge port of the gas-solid separator (2.1), a third outlet is provided at the bottom of the transition bin (2.4), and the third outlet is connected to the inlet of the feeding mechanism (3.1) via a fourth valve (2.5).

10. The roasting system according to any one of claims 2 to 4, characterized in that: The roasting furnace (3) is a rotary heating furnace; the rotary heating furnace comprises a rotary drum assembly (3.2) and a discharge hood (3.4) rotatably connected to the discharge end of the rotary drum assembly (3.2); an air inlet of the roasting furnace (3) is arranged at the feed end of the rotary drum assembly (3.2); a roasting material outlet is arranged at the bottom of the discharge hood (3.4), and a top of the discharge hood (3.4) is connected to a first medium inlet; the feeding mechanism (3.1) is a spiral feeding mechanism.

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