Pneumatic conveying assembly, pneumatic conveying device and waste battery powder roasting system

Abstract

The utility model relates to a pneumatic conveying assembly, pneumatic conveying device and waste battery powder roasting system.The pneumatic conveying assembly comprises a cylinder, the cylinder is provided with a first air inlet, a feeding port and an outlet which are sequentially distributed from bottom to top, a grinding mechanism is arranged in the cylinder, the position of the grinding mechanism is not higher than the position of the feeding port, and the position of the grinding mechanism is lower than the position of the discharging port. The position of the first air inlet is not higher than that of the grinding mechanism. According to the pneumatic conveying assembly, crushing, grinding, dispersing, screening and possibly needed preheating of material powder are integrated in the barrel, investment of pretreatment equipment such as material powder crushing equipment and a gas-solid mixer can be effectively reduced, the equipment integration degree is high, the structural compactness of pneumatic conveying equipment can be improved, the structural complexity is simplified, the occupied area is saved, and the cost is reduced. The equipment cost is reduced.

Description

Technical Field

[0001] The utility model relates to a pneumatic conveying component, a pneumatic conveying device and a roasting system for waste battery powder used for pneumatic conveying, and belongs to the field of pneumatic conveying equipment and roasting equipment. Background Art

[0002] In recycling and processing companies for waste battery powder, such as scrap lithium battery powder, the raw material workshops used to store the waste battery powder are often located some distance from the roasting workshop. Furthermore, waste battery powder often contains toxic organic matter such as residual binders and electrolytes, making it unsuitable for transfer using conveyor belts or manual transport using feeder carts. Furthermore, due to accumulation and compression during handling and transportation, the waste battery powder exhibits varying degrees of agglomeration, making it difficult to effectively transport the agglomerated material using conventional pneumatic conveying equipment. Directly using existing pneumatic conveying equipment can easily cause accumulation and blockage within the pneumatic conveying pipes, disrupting production operations or requiring high conveying pressure to transport even a portion of the powder, significantly impacting conveying efficiency and, in turn, overall production line efficiency. Adding specialized pretreatment equipment (such as material crushing mechanisms) for pretreatment prior to transport increases processing costs and equipment footprint, while also reducing production efficiency. Therefore, efficient, smooth, and environmentally friendly transportation of pre-roasted battery powder is a major challenge currently facing waste battery powder recycling companies.

[0003] To this end, the applicant has specifically developed a disturbance enhancement component, a pneumatic conveying system and a roasting system for powder conveying. However, during further research and development, the applicant found that the above-mentioned equipment / system still has room for improvement in terms of structural compactness, dispersion and conveying efficiency. Utility Model Content

[0004] In view of the shortcomings of the existing technology, one of the purposes of the present invention is to provide a pneumatic conveying component that can be used for pneumatic conveying of powder containing agglomerates; the second purpose of the present invention is to provide a pneumatic conveying device; the third purpose of the present invention is to provide a roasting system for waste battery powder.

[0005] In order to solve the above technical problems, the technical solutions of the present invention are as follows:

[0006] The pneumatic conveying component used for pneumatic conveying includes a cylinder, which is provided with a first air inlet, a feed port and an outlet distributed from bottom to top. A grinding mechanism is provided in the cylinder, and the position of the grinding mechanism is not higher than the position of the feed port, and the position of the first air inlet is not higher than the position of the grinding mechanism.

[0007] Thus, the gaseous medium can be input through the first air inlet, and the powder to be conveyed can be input through the feed port. Under the action of the input gaseous medium, the powder with smaller particle size moves upward with the gaseous medium and mixes with the gaseous medium, and enters the subsequent components. The powder with larger particle size (such as agglomerated or agglomerated powder) falls into the grinding operation space of the grinding mechanism under the action of gravity, and is further dispersed, crushed, and ground by the grinding mechanism. At the same time, under the action of the gaseous medium, the powder at the bottom is disturbed and more fully dispersed, crushed, and ground. The refined powder continues to rise and enter the subsequent components, preventing excessive powder from accumulating at the grinding mechanism and affecting the normal operation of the pneumatic conveying components. Therefore, through the coordinated cooperation of the mechanical field and the airflow field, the powder entering the downstream side of the conveying cylinder is all relatively fine powder, which can prevent agglomerated powder from clogging the pneumatic conveying related components, effectively ensuring or improving the smoothness of the pneumatic conveying process.

[0008] Furthermore, the pneumatic conveying assembly of the present invention combines the functions of dispersing and refining the powder and initially mixing the powder with the gas medium. This eliminates the need for a powder crushing mechanism upstream of the pneumatic conveying equipment, allowing for smooth pneumatic conveying of the powder. Furthermore, there is no need for a gas-solid mixer or other equipment at the front end of the pneumatic conveying equipment. Therefore, the pneumatic conveying assembly of the present invention offers at least one advantage, including a simpler and more compact structure.

[0009] Furthermore, at least one sieve plate is provided between the feed inlet and the outlet. Thus, on the one hand, the sieve plate can block larger powder particles, while allowing only smaller powder particles to rise and enter the downstream side, thus preventing agglomerated materials from entering the downstream side and better ensuring the smoothness of the entire pneumatic conveying process. On the other hand, as the powder rises with the gas medium, some of the powder (especially larger powder particles) will collide with the sieve plate at a relatively high speed upon reaching the sieve plate, thereby being further broken down by the mechanical impact force. Simultaneously, upon impact, the powder is more evenly dispersed in the gas medium, thereby further improving the mixing uniformity between the powder and the gas medium, helping to further improve the smoothness of the pneumatic conveying process. When the gas medium is a hot gas medium, it can also further enhance the heating and volatilization effects on the powder.

[0010] Preferably, the cylinder includes an upper cylinder and a lower cylinder distributed upward and downward, the outlet is arranged on the upper cylinder, and the first air inlet and the feed inlet are both arranged on the lower cylinder.

[0011] Furthermore, the at least one sieve plate is disposed within the lower cylinder and above the feed port. When the gaseous medium is hot gas, the mechanical field, thermal field, and airflow field in the space below the sieve plate synergistically dry, volatilize, pulverize, break up, and mix the material, ensuring efficient dispersion, preheating, and pretreatment of the material before pneumatic conveying, ensuring smooth subsequent pneumatic conveying, and preparing the material's form for further preheating.

[0012] Furthermore, the upper and lower barrels are detachably sealed and connected. More preferably, the sieve plate is height-adjustably mounted within the lower barrel. This facilitates maintenance and overhaul of the barrel and its internal components. The position of the sieve plate can also be adjusted between the top of the lower barrel and the feed inlet based on the properties of the powder (type, degree of agglomeration, characteristics, etc.) and feeding and conveying requirements / parameters, further optimizing the feed grading process.

[0013] Furthermore, the sieve plate includes a plurality of sieve bars; thus, corresponding sieve channels are formed by the arrangement of the sieve bars.

[0014] Preferably, the plurality of screen bars are evenly distributed radially around the central axis of the cylinder; more preferably, the screen plate further comprises at least one annular member, and the plurality of screen bars are fixedly connected to the annular member; in this way, through the cooperation between the annular member and the screen bars, sieve holes with a small difference in cross-sectional area are formed, ensuring that the particle size difference of the powder entering the downstream side is small.

[0015] Preferably, the bottom surface of the screen bar is provided with a plurality of downwardly projecting bumps and / or ridges. The cross-sectional area of ​​the bumps perpendicular to the central axis of the cylinder gradually increases from bottom to top, while the cross-sectional area of ​​the ridges perpendicular to the central axis of the cylinder gradually increases from bottom to top. This forms a "cutting edge" on the bottom surface of the screen bar, which better breaks up powder that impacts the screen plate. At the same time, it prevents powder from accumulating on the bottom surface of the screen bar due to air pressure, preventing blockage of the screen plate during long-term operation.

[0016] Furthermore, it also includes a driving mechanism and a rotating shaft arranged in the cylinder body, the rotating shaft is transmission-connected to the driving mechanism, the rotating shaft extends along the length direction of the cylinder body, the crushing and grinding mechanism is arranged on the rotating shaft, and the lower end of the rotating shaft extends downwardly out of the cylinder body.

[0017] Furthermore, the upper end of the rotating shaft extends upward to above the position of the feed port, and the crushing and dispersing mechanism includes a crushing and dispersing section located on the rotating shaft, and the crushing and dispersing section includes a plurality of blades, and the plurality of blades are distributed in sequence along the length direction of the rotating shaft; thereby, the blades can preliminarily disperse and crush the fallen lumps or large particles of powder, and crush and disperse the materials suspended in this section due to the holding force of air and gravity and the limitation of the screen plate, so that only relatively dense or larger lumps selectively enter the fine grinding section, thereby improving the working efficiency of the fine grinding section, extending the service life of the equipment, and further mechanically stirring the gas-solid mixture in the rising state, further improving the gas-solid mixing uniformity effect.

[0018] Preferably, the blades include a plurality of blades, and the plurality of blades are evenly distributed along the circumference of the rotating shaft.

[0019] Preferably, the paddles comprise multiple blades, evenly distributed along the circumference of the rotating shaft, with axially adjacent blades staggered. This further enhances the turbulence and flow path of the material flow within the pneumatic conveying assembly, and further increases the chances of powder colliding with and contacting the blades, thereby further improving the effects of particle refinement, heating, and volatilization and separation of organic matter.

[0020] Preferably, the paddle includes a plurality of blades, and the plurality of blades are evenly distributed along the circumference of the rotating shaft. The blades are inclined along the circumference of the rotating shaft so that the angle between the width direction of the blade and the cross-section of the cylinder is 30-60°. In this way, while enhancing the airflow disturbance effect, the rotating shaft drives the blades to rotate, providing effective suction, making the material flow smoother in the pneumatic conveying component, and avoiding the accumulation of powder at the blades. In addition, the striking working surface of the blade in the vertical direction can be increased to optimize the dispersion and crushing effect of mechanical striking.

[0021] Furthermore, the crushing and grinding mechanism further comprises a fine grinding section located on the rotating shaft, and the crushing and dispersing section and the fine grinding section are distributed above and below.

[0022] More preferably, the system further comprises an air inlet pipe, wherein the rotating shaft is a hollow tube, the outlet of the air inlet pipe is rotatably connected to the lower end of the rotating shaft via a rotary joint, and the upper end of the rotating shaft is sealed. Preferably, the rotating shaft is provided with a plurality of air holes in the section corresponding to the fine grinding section; the blades have cavities connected to the rotating shaft, and the blades are provided with a plurality of air holes connected to the cavities. Thus, gaseous medium can be introduced through the air inlet pipe and ejected from the air holes in the rotating shaft and blades of the fine grinding section. Together with the gaseous medium introduced through the first air inlet, a multi-dimensional impingement airflow is formed, thereby multi-dimensionally disturbing the powder, improving mixing, preventing powder accumulation on the blades, and pushing the fine grinding section material toward the enhanced fine grinding area formed by the cylinder wall and the fine grinding mechanism. Furthermore, the air inlet pressures of the first air inlet and the air inlet pipe can be independently controlled, thereby controlling the air inlet pressure differential, achieving coordinated coordination between the various sections and further optimizing pneumatic conveying and preheating effects.

[0023] Preferably, the air holes are arranged in the front, middle or rear sections of the blades. More preferably, the air holes of adjacent blades are staggered in front and back in the axial direction. Thus, the gas medium forms staggered turbulent flows in different spaces within the pneumatic conveying component, which has a better disturbance dispersion effect.

[0024] Furthermore, the fine grinding section includes a plurality of mounting frames for materials to pass through, and the plurality of mounting frames are fixed on the rotating shaft in sequence along the length direction of the rotating shaft, and a plurality of rotatable grinding rollers are provided between adjacent mounting frames, and the grinding rollers are clearance-matched with the inner wall of the cylinder; thus, on the one hand, the grinding rollers rotate with the rotating shaft, and on the other hand, during operation, the powdered material can enter between the grinding rollers and the inner wall of the cylinder, and the grinding rollers rotate on themselves, thereby crushing this part of the powdered material.

[0025] Preferably, the plurality of grinding rollers are evenly distributed around the circumference of the rotation axis;

[0026] Preferably, axially adjacent grinding rollers are staggered with each other;

[0027] Preferably, the mounting bracket comprises a mounting ring having a coaxial axis with the rotating shaft, and the mounting ring is fixed to the rotating shaft via a plurality of mounting columns.

[0028] Furthermore, the device includes a central shaft and spiral blades disposed within the barrel and above the feed port. The spiral blades are fixed between the central shaft and the inner wall of the barrel, forming a spiral conveying channel from bottom to top. This prolongs the flow path of the gas-solid mixture within the barrel, helps improve homogenization, and reduces the size of the device.

[0029] Preferably, the spiral pitch of the spiral blades gradually decreases from bottom to top; this creates a spiral conveying channel that is wider at the bottom and narrower at the top. This progressively enhances the heat transfer process (when at least part of the gas medium is hot gas), effectively reducing the temperature difference between the material at the end of the barrel and the preheated air temperature, and helping to fully preheat the powder to a temperature close to that of the hot gas medium. Simultaneously, the narrowing of the conveying channel increases the channel pressure, which, combined with the sudden increase in the conveying channel at the top of the barrel, creates a pressure differential, further enhancing gas-solid mixing, dispersion, and heat transfer.

[0030] Preferably, the central shaft is a hollow tube sealed at both ends, and a second air inlet for inputting gas into the central shaft is provided on the central shaft; more preferably, a plurality of air holes are provided on the central shaft, and even more preferably, the density of the air holes on the central shaft gradually increases from bottom to top, thereby gradually increasing the turbulence and enhancing the uniformity of the gas-solid mixture output from the outlet. When the input gas is hot gas, on the one hand, the hot gas carrying sufficient heat is ensured to exchange heat with the powder preheated to a certain degree near the outlet, maximizing the use of the heat in the hot gas, ensuring that the powder is heated sequentially in the forward direction, and reducing the temperature difference between the material and the hot gas at the outlet. On the other hand, the powder is allowed to carry a sufficient amount of hot gas into the gas-solid separator stage, reducing the temperature drop in the gas-solid separation stage, thereby better improving the subsequent treatment effects such as roasting.

[0031] More preferably, a cavity connected to the inner cavity of the central axis is provided in the spiral blade, and a plurality of air holes connected to the cavity are provided on the spiral blade. As a result, the gas medium flowing out from the air holes of the spiral blade and / or the central axis has a further impact on the gas-solid mixture, thereby enhancing the disturbance and homogenization effect; when the gas medium introduced is hot gas, the hot gas can perform secondary heating on the powder, thereby effectively extending the preheating path and further reducing the length of the cylinder.

[0032] More preferably, the air holes are located on the upper surface of the spiral blade. More preferably, the upper surface of the spiral blade has a certain thickness, and the air holes are oriented in the same direction as the upward spiral. In this way, the gas medium is ejected from the spiral blade in the same direction as the spiral and at an upward angle, forming an upward sub-flow to promote the vertical transport of the material flow, and forming a lateral flow to increase material disturbance and heat transfer (when the gas medium is hot gas).

[0033] Moreover, the change in airflow direction and the impact process during the rotation of the shaft make the gas-solid contact more complete, thereby further preheating the material (when the gas medium is hot gas), and at the same time it is conducive to the continuous upward transportation of the powder.

[0034] Preferably, the upper end of the central axis extends upward to or above the location of the outlet, and the vertical height of the spiral conveying channel is less than the height of the central axis, preferably 20%-80% of the central axis height, and more preferably 40%-60%. In this way, a vertical channel is formed near the discharge port of the upper cylinder, causing a sudden increase in relative space relative to the spiral conveying channel. On the one hand, the gas pressure difference and material concentration difference are generated to promote smooth upward conveyance of materials. On the other hand, a regional explosive impact is formed, further optimizing the dispersion, mixing, and heat transfer effects.

[0035] Preferably, the spiral blades and the central shaft are both made of a thermally conductive material. More preferably, the thermally conductive material comprises one or more of a copper alloy, an aluminum alloy, a magnesium alloy, and steel. Thus, when the gas medium employed is hot gas, after stable operation, the temperature of the spiral blades and the central shaft rises, and the powder contacts and collides with the spiral blades and the central shaft during its rise, further dispersing the powder and achieving solid-solid contact heat transfer, thereby enhancing the heating effect.

[0036] Based on the same inventive concept, the present invention also provides a pneumatic conveying device, comprising the pneumatic conveying assembly and the gas-solid separator as described above, which are connected in sequence.

[0037] Furthermore, the exhaust port of the gas-solid separator is connected to a first fan.

[0038] Furthermore, the gas-solid separator is a dust collector.

[0039] Based on the same inventive concept, the utility model also provides a waste battery powder roasting system, including a roasting furnace and the pneumatic conveying device as described above, and the discharge port of the gas-solid separator is connected to the roasting furnace.

[0040] Furthermore, the roasting system also includes an indirect heat exchanger, which 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, and the second medium outlet is connected to a first valve and a third valve. The outlet of the first valve is connected to the first air inlet, and the outlet of the third valve is connected to the air inlet of the roasting furnace.

[0041] Furthermore, the second medium outlet is connected to the first valve, the second valve and the third valve, and the outlet of the second valve is connected to the second air inlet, thereby inputting hot air into the spiral feeding channel to further increase the preheating temperature of the material powder; at the same time, for waste battery powder containing organic matter such as binders and electrolytes, it can further promote the volatilization of organic matter from the perspectives of increasing the preheating temperature and diluting the gas-solid mixture, thereby avoiding organic matter from entering the roasting furnace as much as possible, helping to improve the completeness of the roasting reaction and reduce the amount of toxic gas generated during the roasting process.

[0042] Furthermore, the discharge port of the gas-solid separator is connected to the roasting furnace through a feeding mechanism, and further, the feeding mechanism is a spiral feeding mechanism.

[0043] Based on the same inventive concept, the present invention also provides a method for roasting waste battery powder, wherein the waste battery powder to be processed is fed into a roasting furnace for roasting through the pneumatic conveying device as described above; or, the waste battery powder to be processed is roasted through the roasting system as described above.

[0044] Furthermore, a method for roasting waste battery powder comprises the following steps:

[0045] S1. Start the roasting furnace. At the same time, continuously input air through the second medium inlet and open the third valve to heat the air.

[0046] S2. After the target temperature is reached in the roasting furnace, the crushing and grinding mechanism is turned on to feed the waste battery powder to be processed into the pneumatic conveying assembly through the feed inlet; at the same time, the first valve is opened to allow part of the hot air output from the second medium outlet to enter the pneumatic conveying assembly, and after crushing, scattering and mixing, a gas-solid fine mixture is obtained at the outlet;

[0047] Preferably, the temperature of the solid material at the outlet is controlled to be 100-300°C, more preferably 200-280°C;

[0048] S3, inputting the gas-solid fine mixture into a gas-solid separator, and performing gas-solid separation to obtain hot waste battery material powder and tail gas;

[0049] S4, feeding the hot waste battery material powder into the roasting furnace through the feeding mechanism, and simultaneously feeding part of the hot air output from the second medium outlet into the roasting furnace, and obtaining roasting material and high-temperature flue gas after roasting;

[0050] S5. Inputting the high-temperature flue gas into an indirect heat exchanger through the first medium inlet, and indirectly exchanging heat with the air input through the second medium inlet, thereby obtaining low-temperature flue gas at the first medium outlet and hot air at the second medium outlet;

[0051] S6. Repeat S2-S5 until all the waste battery powder to be processed is roasted.

[0052] Furthermore, in S2, some hot air is input through the air inlet pipe to further enhance the disturbance, heating, crushing and / or stirring effects.

[0053] Furthermore, in S2, part of the hot air is input through the second air inlet to further enhance the disturbance, heating, crushing and / or stirring effects.

[0054] Preferably, the amount of hot air input through the first air inlet is greater than the amount of hot air input through the second air inlet.

[0055] Optionally, the battery is an alkali metal battery. Furthermore, the alkali metal battery includes one or more of a lithium battery and a sodium battery.

[0056] Compared with the prior art, at least some embodiments of the present invention have the following beneficial effects:

[0057] (1) The pneumatic conveying assembly of the present invention integrates the grading, grinding, dispersion, screening and possible preheating of the powder into the pneumatic conveying cylinder, which simplifies the structure of the single equipment and the transmission links between the equipment, and can effectively reduce the investment in pretreatment equipment such as powder crushing equipment and gas-solid mixer. The equipment has a high degree of integration, which helps to improve the structural compactness of the pneumatic conveying equipment, simplify the structural complexity, save floor space, reduce equipment costs, and facilitate industrial production and application.

[0058] (2) The pneumatic conveying assembly of the present invention can make full use of the powder state of most of the powder itself, and use the gravity difference of the agglomerated powder itself to perform functional division, division of labor, and selective dispersion and grinding in coordination with each other. When the pneumatic conveying assembly of the present invention is in operation, the powder that is originally well dispersed in the input powder can directly pass through the sieve plate into the subsequent conveying link. The relatively loose agglomerates can be better dispersed by the mechanical stirring of the blades in the crushing and dispersing section of the grinding mechanism and the air flow disturbance, forming qualified powder that flows upward to the downstream side; large pieces of material or dense agglomerated powder that the blades cannot disperse selectively enter the fine grinding area, greatly reducing the amount of grinding and dispersion, which helps to improve operating efficiency. The different functional sections of the grinding mechanism are used for grinding and pulverization, and the material is graded and segmented according to its characteristics, which improves the grinding efficiency and grinding effect, reduces the grinding load, and further reduces the processing cost.

[0059] (3) The pneumatic conveying component of the present invention fully utilizes multiple physical fields such as space field, thermal field, mechanical field, gas field, etc. to synergistically enhance the mixing, grinding, dispersion and heat conduction effects during the conveying-grinding process. It is not only beneficial to the dispersion, mixing and grinding process of the powder, but also effectively promotes the effective separation of organic matter in the raw materials and the target material, that is, the volatilization separation of organic matter is concentrated in the cylinder, making preparations for the next stage of roasting in terms of dispersion, uniformity, temperature and purity.

[0060] (4) When the pneumatic conveying assembly of the present invention is in operation, the powdered material is spirally conveyed in the spiral conveying channel, and secondary preheated gas can be introduced through the second air inlet to form multi-directional micro-disturbance for sufficient mixing and heat transfer, thereby further optimizing the dispersion state. If battery powder containing organic matter is processed, the organic matter can be more fully volatilized and separated, avoiding entering the subsequent roasting treatment stage.

[0061] (5) The roasting system of the present invention realizes full and efficient utilization of the roasting waste heat system through the cooperation of the pneumatic conveying component, the gas-solid separator, the roasting furnace, the heat exchange system, etc. Specifically, the roasting waste heat enters the pneumatic conveying component from different parts, and the preheating utilization efficiency and preheating effect are effectively improved by utilizing the structural setting of the pneumatic conveying component and the waste heat gas distribution system, so as to make full preparations for the preheating of materials and the pre-separation of organic matter in the roasting process, effectively avoid the phenomena of compaction and ring formation caused by the temperature difference of materials in the roasting process, optimize the roasting process, and improve the roasting efficiency and effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 It is a cross-sectional view of a pneumatic conveying assembly for pneumatic conveying according to Example 1 of the present utility model.

[0063] Figure 2 It is a front view of the rotating shaft, blades and grinding part of the grinding mechanism of Example 1 of the present utility model.

[0064] Figure 3 It is a three-dimensional diagram of the rotating shaft, blades and grinding parts of the grinding mechanism of Example 1 of the present utility model.

[0065] Figure 4 It is a schematic diagram of the internal structure of the corresponding section of the spiral conveying channel of Example 1 of the present utility model.

[0066] Figure 5 It is along Figure 4 Sectional view along line AA.

[0067] Figure 6 It is a schematic diagram of the external structure of the pneumatic conveying component of Example 1 of the present utility model.

[0068] Figure 7 This is a simplified structural diagram of the roasting system of Example 12 of the present invention.

[0069] Figure 8 It is a cross-sectional view of a pneumatic conveying assembly for pneumatic conveying according to Example 6 of the present utility model.

[0070] Figure 9 It is along Figure 8 Cross-sectional view along line BB. DETAILED DESCRIPTION

[0071] The present invention will be described in detail below with reference to the following embodiments. It should be noted that the embodiments and features of the embodiments may be combined unless they conflict. For ease of description, the words "upper," "lower," "left," and "right" appear below merely to indicate the directions of up, down, left, and right in the accompanying drawings and do not limit the structure.

[0072] Example 1

[0073] See also Figures 1-6 The pneumatic conveying assembly for pneumatic conveying includes a cylinder 1, which includes an upper cylinder and a lower cylinder. The upper cylinder is provided with a discharge port 304, and the lower cylinder is provided with a first air inlet 101 and a feed port 102, which are arranged in order from bottom to top. The first air inlet 101 is tangentially connected to the cylinder 1, and the outlet 304 is located on the top side of the cylinder and is also tangentially connected to the cylinder. A grinding mechanism 201 is provided in the cylinder 1. The grinding mechanism 201 is located below the feed port 102, and the first air inlet 101 is located on the bottom side of the grinding mechanism 201. A one-way valve is provided at the feed port to prevent backflow of powder or gas in the cylinder 1.

[0074] A sieve plate 204 is provided above the feed port 102. The sieve plate 204 comprises a plurality of screen bars 2041, which are evenly distributed radially around the central axis of the cylinder 1. The sieve plate 204 also comprises an annular member 2042, to which the screen bars 2041 are fixedly connected. The inner ends of the screen bars 2041 are rotatably connected to the rotating shaft via deep groove ball bearings with sealing rings.

[0075] It also includes a driving mechanism and a rotating shaft 2 arranged in the lower cylinder. The rotating shaft 2 extends along the length direction of the lower cylinder. The crushing and grinding mechanism 201 is arranged on the rotating shaft 2. The lower end of the rotating shaft 2 extends downward to the outside of the cylinder 1, which can facilitate the transmission connection between the rotating shaft and the driving mechanism; the section of the rotating shaft 2 extending outside the cylinder 1 is transmission-connected to the driving mechanism.

[0076] The upper end of the rotating shaft 2 extends upward to above the position of the feed port 102. The crushing and grinding mechanism 201 includes a crushing and dispersing section and a fine grinding section located on the rotating shaft 2 and distributed above and below. The crushing and dispersing section includes a plurality of blades 202, and the plurality of blades 202 are distributed in sequence along the length direction of the rotating shaft 2; a limiting mechanism 205 for allowing materials to pass through is fixed in the lower cylinder, and the rotating shaft 2 is rotatably connected to the limiting mechanism 205. More specifically, the limiting mechanism 205 includes a limiting frame fixed on the inner wall of the lower cylinder, and the rotating shaft passes through the limiting frame and is rotatably connected to the limiting frame through a deep groove ball bearing with a sealing ring.

[0077] The blades 202 include a plurality of blades, which are evenly distributed along the circumference of the rotating shaft 2, and the axially adjacent blades are staggered. The blades are inclined along the circumference of the rotating shaft so that the angle between the width direction of the blades and the cross section of the cylinder 1 is 45 degrees.

[0078] The grinding mechanism includes four mounting frames 206 for materials to pass through, and the four mounting frames 206 are fixed on the rotating shaft 2 in sequence along the length direction of the rotating shaft 2. Three rotatable grinding rollers 207 are provided between adjacent mounting frames 206, and the grinding rollers 207 are clearance-matched with the inner wall of the cylinder 1; the three grinding rollers 207 between adjacent mounting frames 206 are evenly distributed around the circumference of the rotating shaft 2; the axially adjacent grinding rollers 207 are staggered with each other; the mounting frame 206 includes a mounting ring 2061 that is coaxial with the rotating shaft 2, and the mounting ring 2061 is fixed to the rotating shaft 2 through four mounting columns 2062.

[0079] It also includes a central axis 303 and spiral blades 302 arranged in the upper cylinder. The spiral blades 302 are fixed between the central axis 303 and the inner wall of the cylinder 1 to form a spiral conveying channel 3 from bottom to top; the spiral pitch of the spiral blades 303 gradually decreases from bottom to top.

[0080] Example 2

[0081] Repeat Example 1, with the only difference being that: an air inlet pipe is also included, the rotating shaft 2 is a hollow tube, the outlet of the air inlet pipe is rotatably connected to the lower end of the rotating shaft 2 via a rotary joint 23, and the upper end of the rotating shaft 2 is sealed; the blade has a cavity, the cavity is connected to the rotating shaft, and a plurality of air holes 208 connected to the cavity are provided on the blade.

[0082] The central axis 303 is a hollow tube sealed at both ends, and is provided with a second air inlet 301 for inputting gas into the central axis 303; the central axis 303 is provided with a plurality of air holes 305, and the density of the air holes 305 on the central axis 303 gradually increases from bottom to top; a cavity is provided in the spiral blade 302 and is connected to the inner cavity of the central axis 303, and the spiral blade 302 is provided with a plurality of air holes connected to the cavity, and the air holes are located on the upper surface of the spiral blade 302; the spiral blade 302 and the central axis 303 are both made of steel.

[0083] Example 3

[0084] Example 1 is repeated, with the only difference being that the lower end of the upper cylinder and the upper end of the lower cylinder are detachably sealed and connected, and the sieve plate 204 is height-adjustably disposed in the lower cylinder.

[0085] Example 4

[0086] Repeat Example 1, with the only difference being that a plurality of downwardly protruding bumps and / or convex strips are provided on the bottom surface of the screen bar 2041, and the cross-sectional area of ​​the bumps perpendicular to the central axis of the cylinder 1 gradually increases from bottom to top, and the cross-sectional area of ​​the convex strips perpendicular to the central axis of the cylinder 1 gradually increases from bottom to top.

[0087] Example 5

[0088] Repeat Example 1, with the only difference being that the upper end of the central axis 303 extends upward to the location of the discharge port 304 , and the vertical height of the spiral conveying channel 3 is less than the height of the central axis 303 , specifically 1 / 2 of the height of the central axis 303 .

[0089] Example 6

[0090] Repeat Example 1, except that: Figure 8-Figure 9 The upper end of the central axis 303 extends upward to a position above the position of the discharge port 304.

[0091] Example 7

[0092] Example 2 is repeated, with the only difference being that a plurality of air holes are provided on the section of the rotating shaft 2 corresponding to the fine grinding section.

[0093] Example 8

[0094] Example 2 is repeated, with the only difference being that the air holes are respectively arranged in the front section, middle section or rear section of the blade, so that the positions of the air holes of axially adjacent blades are staggered front to back.

[0095] Example 9

[0096] Example 2 is repeated, with the only difference being that the density of the pores on the central axis 303 gradually increases from bottom to top.

[0097] Example 10

[0098] Example 2 was repeated, with the only difference being that the thickness of the upper surface of the spiral blade was 3 mm, and the direction of the air holes was consistent with the upward spiral direction.

[0099] Example 11

[0100] A pneumatic conveying device comprises a pneumatic conveying assembly and a gas-solid separator as described in Example 2, which are connected in sequence.

[0101] Example 12

[0102] See also Figure 7 The calcination system of waste lithium battery powder includes a silo assembly 4, a pneumatic conveying assembly as described in Example 2, a gas-solid separator 5, a calcination furnace 10, an indirect heat exchanger 15, and an exhaust gas treatment system 19;

[0103] The silo assembly 4 includes a silo body for temporarily storing waste lithium battery powder. A first level gauge for monitoring the material level is provided in the silo body. The bottom of the silo body is connected to the feed port 102 through a fifth valve (rotary sealing valve for convenient quantitative feeding).

[0104] The discharge port of the gas-solid separator 5 is connected to a transition chamber 7, which has a discharge port at its bottom. A fifth valve 8 is located at the third outlet. The feed port of the roasting furnace 10 is connected to the discharge port via a feed mechanism 9 (a spiral feed mechanism). The exhaust port of the gas-solid separator 5 is connected to a first fan 6, the outlet of which is connected to an exhaust gas treatment system 19.

[0105] The indirect heat exchanger 15 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, and the second medium inlet and the second medium outlet are interconnected. The first medium inlet is connected to the roasting flue gas outlet, and the first medium outlet is connected to the exhaust gas treatment system 19 via a second fan 18. The second medium inlet is equipped with a third fan 17, and the second medium outlet is connected to a fourth valve 16 (ventilation butterfly valve). The outlet of the fourth valve 16 is connected to a first valve 20 (ventilation butterfly valve), a second valve 21 (ventilation butterfly valve), a third valve 22 (ventilation butterfly valve), and a seventh valve 24 (rotary butterfly valve). The outlet of the first valve 20 is connected to the first air inlet 101, the outlet of the second valve 21 is connected to the second air inlet 301, and the outlet of the third valve 22 is connected to the air inlet of the roasting furnace 10. The outlet of the seventh valve 24 is connected to the inlet of the air intake pipe.

[0106] In this roasting system, the pneumatic conveying assembly, gas-solid separator, and related pipelines not only achieve pneumatic conveying of the waste lithium battery powder, but also complete various pretreatment processes, including preheating, refinement, and organic matter removal. The waste lithium battery powder and some hot air are fed into the cylinder 1, while some lightweight powder rises directly with the hot air. Agglomerated powder is broken up and dispersed by the high-speed crushing and stirring action of the grinding mechanism and blades, fully mixed with the hot air, and suspended in the hot air, rising upward. In the gas-solid separator, the waste lithium battery powder is separated from the air and enters the transition chamber 7. The resulting gas passes through the first blower 6 and enters the exhaust gas treatment system.

[0107] A second level gauge is installed within the transition chamber 7 to monitor the material level within the transition chamber and ensure a tight seal between the transition chamber 7 and the material. This prevents gases containing organic volatiles and sequestrants from entering the roaster and reversely permeating the roaster's gas-solid separator. The discharge port is connected to the inlet of the feed mechanism 9 via a fifth valve 8 (rotary sealing valve). The transition chamber acts as a buffer and blocks the discharge port of the gas-solid separator, forcing gas within the separator to flow toward its exhaust port and preventing gas from within the roaster from entering the separator.

[0108] The roasting furnace 10 is a rotary heating furnace. It features a rotating drum assembly, with the feed mechanism 9 and third valve 22 both connected to the feed end of the assembly. A discharge hood 11, rotatably connected to the drum assembly, is located at the discharge end of the drum. The bottom of the hood 11 is equipped with a roasting material outlet, which is connected to a cooling device 13 via a sixth valve (rotary sealing valve) 12 to cool the roasting material. The top of the hood 11 is connected to the first medium inlet. The rotary drum assembly is equipped with a heating module to heat the material within. Within the roasting furnace, the waste lithium battery powder and hot air are further heated, causing a roasting reaction and releasing a large amount of heat. Since the waste lithium battery powder and air have been heated before entering the rotary drum assembly and have reached a certain high temperature state, compared with the waste lithium battery powder and air at room temperature, they only need to absorb a small amount of heat to quickly reach the roasting reaction temperature in the rotary drum assembly, which can greatly reduce the heating time and heating energy consumption; moreover, the waste lithium battery powder has been fully broken up and organic matter removed during the pneumatic conveying process, so that the roasting reaction can be carried out more efficiently, fully and smoothly.

[0109] A dust removal mechanism 14 is provided between the first medium inlet and the roasting flue gas outlet of the discharge hood 11 to remove dust particles contained in the high-temperature flue gas. The dust removal mechanism 14 includes a cyclone dust collector and a high-temperature dust collector. The roasting flue gas outlet, cyclone dust collector, high-temperature dust collector, and first medium inlet are sequentially connected. The discharge ports of the cyclone dust collector and the high-temperature dust collector are both connected to the cooling device 11. Optionally, the high-temperature dust collector is a conventional high-temperature-resistant dust collector, such as those described in prior art such as CN101559307A and CN110743265B.

[0110] In this way, pneumatic conveying can effectively solve the problem of transferring and transporting waste lithium battery powder between different workshops, without causing dust pollution and with high efficiency. At the same time, with the help of the hot air produced by the indirect heat exchanger, not only the pneumatic conveying of waste lithium battery powder is realized, but also the waste lithium battery powder is preheated and dispersed during the pneumatic conveying, which helps to ensure the smoothness of the pneumatic conveying and improve the subsequent roasting efficiency and roasting adequacy.

[0111] In the above-mentioned roasting system, the high-temperature flue gas generated by the roasting furnace during the air roasting treatment of the waste lithium battery powder can be exchanged with air in the indirect heat exchanger to achieve cooling of the high-temperature flue gas, which is convenient for subsequent treatment and discharge. At the same time, part of the hot air generated by the indirect heat exchanger enters the pneumatic conveying component through the first air inlet, and the powder enters the pneumatic conveying component through the feed port. Part of the powder rises directly with the air flow, and part of the powder falls and is broken and refined by the blades and / or the grinding mechanism. The hot air is mixed, broken up and preheated with the waste lithium battery powder in the pneumatic conveying component, so that the waste lithium battery powder is fully dispersed and suspended in the hot air to form a gas-solid mixture. At the same time, multiple blades distributed in sequence along the length of the rotating shaft strongly disturb and stir the gas-solid mixture and agglomerated powder, enhancing the turbulence intensity and powder fineness of the gas-solid mixture. The coarse particles of the waste lithium battery powder are further repeatedly broken up and crushed, exposing new surfaces, which can effectively promote the volatilization and separation of organic matter such as residual electrolyte and binder in the waste lithium battery powder, thereby obtaining waste battery fine powder with good fluidity, low organic matter content, and non-agglomeration. This effectively improves the smoothness of pneumatic conveying and reduces the possibility of waste lithium battery powder clogging pipes and other components during transportation to the roasting furnace. In addition, no gas-solid separation is required during the preheating process, making the equipment and operation simple, efficient, and with a low failure rate. Substandard powder is intercepted by the screen plate and further crushed by the impact of the screen plate. Powder with larger particle size falls and is further crushed and refined by the blades and / or grinding mechanism before rising. Powder with smaller particle size rises directly with the hot air.

[0112] In addition, due to the favorable influence of the pneumatic conveying component, when the spiral feeding mechanism transports the waste battery fine powder to the roasting furnace, there is no need to worry about the waste lithium battery powder being agglomerated or agglomerated due to extrusion and other effects, thereby affecting the subsequent roasting effect.

[0113] During roasting, the preheated and fully dispersed waste battery fine powder and hot 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, thereby effectively saving energy consumption, realizing heat recycling, and improving energy utilization.

[0114] Moreover, the particle size of the input waste battery fine powder has been further refined and the amount of organic matter it contains is already quite low. The waste battery fine powder and the active substances it contains are able to come into contact with the hot air more fully, and the competitive reaction between organic matter and air is greatly reduced, thereby making the roasting reaction more efficient and thorough, thereby effectively improving the roasting efficiency and roasting completeness, and obtaining a better roasting effect.

[0115] In addition, the roasting reaction stage is a high-temperature reaction stage. Since the amount of organic matter contained in the waste battery fine powder is already quite low, the possibility of toxic and harmful gases such as fluoride, nitrogen oxides, and dioxins produced by the oxidation and combustion reaction of 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 green and environmentally friendly, and can also greatly reduce the burden and cost of subsequent exhaust gas treatment.

[0116] It can be seen that the roasting system with the above-mentioned pneumatic conveying component and pneumatic conveying device developed by the applicant uses an indirect heat exchanger to perform heat exchange treatment on high-temperature flue gas and air, and uses part of the hot air to perform pneumatic conveying and pretreatment of waste lithium battery powder, remove organic matter in the waste lithium battery powder, and use part of the hot air for air roasting treatment, which can improve the smoothness of the transportation of waste lithium battery powder and solve the problem of raw material transportation faced in the industrial processing process; at the same time, it realizes the full recycling of heat, which is conducive to energy saving and consumption reduction; in addition, the air roasting effect of waste lithium battery powder is better, and the amount of toxic and harmful gases generated is lower. It can be seen that the pneumatic conveying component, pneumatic conveying device and roasting system of the utility model have better industrial application prospects and are conducive to the industrial roasting treatment of waste lithium battery powder.

[0117] Example 13

[0118] The method for roasting waste lithium battery powder (waste lithium iron phosphate battery black powder) comprises roasting the waste battery powder to be processed by the roasting system described in Example 12, comprising the following steps:

[0119] S1. Start the roasting furnace. At the same time, continuously input air through the second medium inlet and open the third valve to heat the air.

[0120] S2. After the target temperature is reached in the roasting furnace, the crushing and grinding mechanism is turned on, and the waste lithium battery powder to be processed is fed into the pneumatic conveying assembly through the feed port; at the same time, the first valve, the second valve, and the seventh valve are turned on, so that part of the hot air output from the second medium outlet enters the pneumatic conveying assembly through the first air inlet, the second air inlet, and the air inlet pipe, respectively. After crushing, scattering, and mixing, a gas-solid fine mixture is obtained at the outlet;

[0121] S3, inputting the gas-solid fine mixture into a gas-solid separator, and performing gas-solid separation to obtain hot waste lithium battery material powder and tail gas;

[0122] S4, feeding the hot waste lithium battery powder into the roasting furnace through the feeding mechanism, and simultaneously feeding part of the hot air output from the second medium outlet into the roasting furnace, and obtaining roasting material and high-temperature flue gas after roasting;

[0123] S5. Inputting the high-temperature flue gas into an indirect heat exchanger through the first medium inlet, and indirectly exchanging heat with the air input through the second medium inlet, thereby obtaining low-temperature flue gas at the first medium outlet and hot air at the second medium outlet;

[0124] S6. Repeat S2-S5 until all the waste lithium battery powder to be processed is roasted.

[0125] The contents described in the above embodiments should be understood as these embodiments are only used to more clearly illustrate the present invention, and are not used to limit the scope of the present invention. After reading the present invention, various equivalent modifications to the present invention made by those skilled in the art fall within the scope defined by the claims attached to this application.

Claims

1. A pneumatic conveying assembly, comprising a cylinder (1), characterized in that: The cylinder (1) is provided with a first air inlet (101), a feed inlet (102), and an outlet (304) which are sequentially distributed from bottom to top. A grinding mechanism (201) is provided inside the cylinder (1). The location of the grinding mechanism (201) is not higher than the location of the feed inlet (102), and the location of the first air inlet (101) is not higher than the location of the grinding mechanism (201).

2. The pneumatic conveying assembly according to claim 1, characterized in that At least one sieve plate (204) is provided between the feed port (102) and the outlet (304).

3. The pneumatic conveying assembly according to claim 2, characterized in that The cylinder (1) comprises an upper cylinder and a lower cylinder which are arranged on the upper and lower sides, and the upper cylinder and the lower cylinder are detachably sealed and connected; And / or, the sieve plate (204) comprises a plurality of sieve bars (2041), a plurality of downwardly protruding convex points and / or convex strips are provided on the bottom surface of the sieve bars (2041), the cross-sectional area of ​​the convex points perpendicular to the central axis of the cylinder (1) gradually increases from bottom to top, and the cross-sectional area of ​​the convex strips perpendicular to the central axis of the cylinder (1) gradually increases from bottom to top; and / or, the sieve plate (204) is arranged in the cylinder (1) in a height-adjustable manner.

4. The pneumatic conveying assembly according to any one of claims 1 to 3, characterized in that: It also includes a driving mechanism and a rotating shaft (2) arranged in the cylinder (1), the rotating shaft (2) being in transmission connection with the driving mechanism, the rotating shaft (2) extending along the length direction of the cylinder (1), the crushing and grinding mechanism (201) being arranged on the rotating shaft (2), and the lower end of the rotating shaft (2) extending downward to the outside of the cylinder (1).

5. The pneumatic conveying assembly according to claim 4, characterized in that The upper end of the rotating shaft (2) extends upward to above the position of the feed port (102), and the crushing and dispersing mechanism (201) includes a crushing and dispersing section located on the rotating shaft (2), and the crushing and dispersing section includes a plurality of blades (202), and the plurality of blades (202) are distributed in sequence along the length direction of the rotating shaft (2); the blades (202) include a plurality of blades.

6. The pneumatic conveying assembly according to claim 5, characterized in that It also includes an air inlet pipe, the rotating shaft (2) is a hollow pipe, the outlet of the air inlet pipe is rotatably connected to the lower end of the rotating shaft (2) via a rotary joint (23), and the upper end of the rotating shaft (2) is sealed; the blade has a cavity, the cavity is connected to the rotating shaft, and a plurality of air holes connected to the cavity are opened on the blade.

7. The pneumatic conveying assembly according to claim 6, characterized in that The crushing and grinding mechanism (201) further comprises a fine grinding section located on the rotating shaft (2); a plurality of air holes are provided on a section of the rotating shaft (2) corresponding to the fine grinding section; the crushing and dispersing section and the fine grinding section are distributed above and below; the fine grinding section comprises a plurality of mounting frames (206) for allowing materials to pass through; the plurality of mounting frames (206) are sequentially fixed to the rotating shaft (2) along the length direction of the rotating shaft (2); a plurality of rotatable grinding rollers (207) are provided between adjacent mounting frames (206); the grinding rollers (207) are clearance-matched with the inner wall of the cylinder (1).

8. The pneumatic conveying assembly according to any one of claims 1-3 and 5-7, characterized in that: It also includes a central shaft (303) and a spiral blade (302) arranged in the cylinder (1) and located above the feed port (102), wherein the spiral blade (302) is fixed between the central shaft (303) and the inner wall of the cylinder (1), forming a spiral conveying channel (3) from bottom to top.

9. The pneumatic conveying assembly according to claim 8, characterized in that The spiral pitch of the spiral blade (302) gradually decreases from bottom to top; and / or, the central shaft (303) is provided with a second air inlet (301) for inputting gas into the central shaft (303), the spiral blade (302) is provided with a cavity communicating with the inner cavity of the central shaft (303), the spiral blade (302) is provided with a plurality of air holes communicating with the cavity, the air holes are located on the upper surface of the spiral blade (302), and the orientation of the air holes is consistent with the direction of the upward spiral; and / or, the upper end of the central shaft (303) extends upward to a position at or above the position of the outlet (304), and the vertical height of the spiral conveying channel (3) is less than the height of the central shaft (303).

10. A pneumatic conveying device, characterized in that: The invention comprises a pneumatic conveying component and a gas-solid separator as described in any one of claims 1 to 9 which are connected in sequence.

11. A system for roasting waste battery powder, comprising a roasting furnace, characterized in that: It also includes the pneumatic conveying assembly according to any one of claims 1 to 9, or the pneumatic conveying device according to claim 10; the discharge port of the gas-solid separator is connected to the roasting furnace.

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