A new energy battery biomass hard carbon production process

Abstract

The application discloses a new energy battery biomass hard carbon production process and relates to the technical field of new energy batteries, which comprises the following steps: biomass is crushed and then sent into a forward air lock feeder; the biomass is sent into a material density control device to control the process density; the biomass is sent into a fixed carbonization furnace; the capacity of the biomass in the fixed carbonization furnace is detected by a level gauge; when the biomass reaches a set capacity, ignition is performed to heat the biomass to a set temperature for carbonization; the carbonized hard carbon precursor is sent into a reverse air lock feeder by a pair of roller material control devices; and the hard carbon precursor is cooled to normal temperature by a non-contact cooling screw conveyor while being conveyed to a closed storage tank for storage. The application can automatically and continuously decompose and carbonize various biomasses, and the whole process does not need additional heating and manual material loading, thereby solving the technical problems of low automation, low carbonization efficiency, high energy consumption and high labor intensity in the prior art.

Description

Technical Field

[0001] This invention relates to the field of new energy battery technology, specifically to a process for producing biomass hard carbon for new energy batteries. Background Technology

[0002] To alleviate range anxiety in new energy vehicles, research on power batteries is gradually moving towards higher energy density and faster charging. Currently, the commonly used anode materials, natural graphite and artificial graphite, are no longer sufficient to meet the material requirements of power batteries. Hard carbon, due to its high specific capacity, excellent cycle life, rate capability, and low-temperature performance, is gradually attracting attention.

[0003] Hard char is pyrolytic char obtained through the pyrolysis and carbonization of biomass. Currently, the main technologies for pyrolysis and carbonization of biomass include anaerobic carbonization and autoclave carbonization. Each of these technologies has its own advantages and disadvantages, as detailed below:

[0004] The first method, anaerobic carbonization, utilizes a very low oxygen content in the air to cause incomplete combustion of biomass, thereby achieving low-temperature pyrolysis (350℃-550℃). Its advantages include the ability to carbonize different types of biomass, a wide carbonization range, and the fact that the carbonization process does not consume heating energy. However, its disadvantages are:

[0005] 1. Because earthen kilns are used, the filling of each carbonization process requires manual labor, resulting in high labor intensity. Dust and high temperature are the most difficult challenges for workers to overcome.

[0006] 2. The carbonization cycle is long. Generally, biomass (such as straw) takes 8-12 hours to carbonize, and larger tree trunks require even longer.

[0007] 3. Long cooling time: The cooling time for good biomass carbonization is generally 10-16 hours. Human intervention (direct water spray cooling) takes about 6-8 hours. However, direct water spray cooling will cause great rapid cooling damage to the furnace body and reduce the service life of the furnace.

[0008] 4. Low carbonization output. The typical size of a traditional earthen kiln is 4×4×2.5 (meters). Each charge is about 2-3.5 tons, the carbonization time is 8-10 hours, and the cooling time is 8-16 hours. Based on this, the carbonization output per day (24 hours) is 2-3.5 tons.

[0009] The second method, carbonization in a dry distillation kettle, utilizes external energy to heat and carbonize the processed biomass inside the kettle. Its advantages include closed-loop carbonization and pyrolysis of biomass, resulting in higher product quality compared to anaerobic carbonization. Furthermore, loading can be done using a crane, enabling semi-mechanized operations and reducing labor intensity. However, its disadvantages are:

[0010] 1. Carbonization in a dry distillation kettle requires external heating to complete the carbonization process, so it needs to be heated continuously for 8-10 hours using wood, coal, or gas, resulting in a large consumption of energy.

[0011] 2. The carbonization cycle is long, taking approximately 8-12 hours. After carbonization, the carbonized material is hoisted into another sealed box for cooling for 8-10 hours.

[0012] 3. Low production efficiency: each furnace can only be filled with 800-1200 kg of material, and only one furnace can be produced per day.

[0013] As can be seen from the above, although hard carbon can be obtained by pyrolysis through anaerobic carbonization and carbonization in a dry distillation kettle, the existing processes still have technical problems such as low automation, low carbonization efficiency, high energy consumption, and high manual labor intensity. Therefore, it is necessary to develop new technologies to improve them. Summary of the Invention

[0014] The purpose of this invention is to overcome the above-mentioned problems in the prior art and provide a biomass hard carbon production process for new energy batteries. This invention can automatically and controllably decompose and carbonize various biomass in a continuous manner, and the entire process does not require additional heating or manual filling. It solves the technical problems of low automation, low carbonization efficiency, high energy consumption, and high manual labor intensity in the prior art.

[0015] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0016] A process for producing hard carbon from biomass for new energy batteries includes the following steps: Biomass is crushed by a pulverizer → fed into a forward-turning airlock by a feeder → fed into a material density control device via a closed conveyor chain located below the forward-turning airlock for process density control → fed into a fixed carbonization furnace by a conveyor chain bed / grate → the capacity of biomass in the fixed carbonization furnace is detected by a level gauge → when the biomass reaches the set capacity, it is ignited using an ignition device to heat the biomass to the set temperature for carbonization → the carbonized hard carbon precursor is fed into a reverse-turning airlock by a roller feeder → the hard carbon precursor is cooled to room temperature and simultaneously transported to a closed storage tank for storage by a non-contact cooling screw conveyor located below the reverse-turning airlock.

[0017] The crusher, feeder, forward airlock, enclosed conveyor chain, material density control device, conveyor chain bed / grate, ignition device, roller material control device, reverse airlock, and non-contact cooling screw conveyor are all controlled by the control system. When the level gauge detects that the biomass has reached the set capacity, it sends a detection signal to the control system. The control system is used to control ignition and the continuous feeding, carbonization, and discharge of biomass according to the detection signal.

[0018] The enclosed conveyor chain, material density control device, conveyor chain bed / grate and roller material control device are sequentially connected between the forward air shut-off fan and the reverse air shut-off fan, and both the forward air shut-off fan and the reverse air shut-off fan are in a closed state.

[0019] The material density control device is fixed at the upper feed end of the fixed carbonization furnace, and the level gauge is fixed above the material density control device and located on one side of the discharge end of the closed conveyor chain; the roller material control device is fixed at the lower discharge end of the fixed carbonization furnace, and the reverse air shut-off fan and non-contact cooling screw conveyor are sequentially fixed below the roller material control device; the ignition device is fixed at the lower end of the fixed carbonization furnace.

[0020] The roller material control device includes a drive mechanism and two rotating rollers. Each of the two rotating rollers is equipped with a material-pushing plate, and the material-pushing plates on the two rotating rollers are staggered. The drive mechanism is connected to the control system and is used to control the rotating rollers to rotate in opposite directions.

[0021] The biomass, after being pulverized by a pulverizer, has a particle size of 10-80 mm.

[0022] The set temperature for carbonizing the biomass in the fixed carbonization furnace is 800-950℃.

[0023] The advantages of using this invention are:

[0024] 1. The hard carbon production process described in this invention employs equipment including a control system, a crusher, a feeder, a forward-facing airlock, a closed conveyor chain, a material density control device, a conveyor chain bed / grate, a level gauge, an ignition device, a roller material control device, a reverse-facing airlock, and a non-contact cooling screw conveyor. In actual production, the forward-facing airlock ensures the entry of biomass raw materials while isolating external oxygen, and the reverse-facing airlock ensures the delivery of hard carbon precursors out of the fixed carbonization furnace while isolating external oxygen. By rationally assembling these devices into a production line and uniformly controlling it under the control system, various biomass can be decomposed and carbonized automatically and continuously. The entire process requires no additional heating or manual loading, offering advantages such as high automation, high carbonization efficiency, low energy consumption, and low labor intensity.

[0025] 2. This invention forms a specific production process by rationally arranging various equipment, which is conducive to the utilization of combustible gases, can achieve continuous carbonization, and is pollution-free throughout the process.

[0026] 3. The present invention can achieve both controllable continuous material discharge and kiln temperature control through the material discharge speed by using a roller material control device.

[0027] 4. The present invention crushes biomass into particles with a particle size of 10-80mm, which has the advantage of facilitating density control of biomass after it enters the kiln, thereby improving the efficiency of biomass carbonization and achieving uniform carbonization of biomass.

[0028] 5. The present invention sets the temperature for carbonizing biomass in a fixed carbonization furnace to 800-950℃, which is beneficial to improving the efficiency of biomass carbonization.

[0029] 6. The carbon yield of biomass is mainly determined by carbonization temperature and time. This invention can achieve precise control of carbonization temperature and time, and can be adjusted at any time according to different biomass materials, which is conducive to improving the carbon yield. Attached Figure Description

[0030] Figure 1 This is a flowchart of the present invention;

[0031] Figure 2 This is a schematic diagram of the structure of the present invention;

[0032] Figure 3 This is a schematic diagram of the forward-facing airlock in this invention;

[0033] Figure 4 This is a schematic diagram of the closed conveyor chain structure in this invention;

[0034] Figure 5 This is a schematic diagram of the structure of the fixed carbonization furnace in this invention;

[0035] Figure 6 This is a schematic diagram of the roller material control device in this invention;

[0036] Figure 7 for Figure 6 A schematic diagram of the AA cross-sectional structure;

[0037] Figure 8 This is a schematic diagram of the reverse-flow fan in this invention;

[0038] Figure 9 This is a schematic diagram of the non-contact cooling spiral compressor in this invention.

[0039] The following are marked in the diagram: 1. Forward air shut-off fan, 2. Enclosed conveyor chain, 3. Material density control device, 4. Fixed carbonization furnace, 5. Ignition device, 6. Double roller material control device, 7. Reverse air shut-off fan, 8. Non-contact cooling screw conveyor, 9. Level gauge, 10. Drive mechanism, 11. Rotating roller, 12. Material feeding plate. Detailed Implementation

[0040] This invention provides a process for producing biomass hard carbon for new energy batteries. The process involves equipment including a control system (installed in a separate machine room, not shown in the figure), a crusher, a feeder, a forward-facing airlock fan 1, a closed conveyor chain 2, a material density control device 3, a conveyor chain bed / grate, a level gauge 9, an ignition device 5, a roller material control device 6, a reverse-facing airlock fan 7, and a non-contact cooling screw conveyor 8.

[0041] like Figure 2-9 As shown, the enclosed conveyor chain 2, material density control device 3, conveyor chain bed / grate, and roller material control device 6 are sequentially connected between the forward air shut-off fan 1 and the reverse air shut-off fan 7, and both the forward air shut-off fan 1 and the reverse air shut-off fan 7 are in a closed state. The feed end of the enclosed conveyor chain 2 is located below the forward air shut-off fan 1, and the discharge end is located above the material density control device 3; the material density control device 3 is fixed to the upper feed end of the fixed carbonization furnace 4, and the level gauge 9 is fixed to the upper part of the material density control device 3 and located on one side of the discharge end of the enclosed conveyor chain 2; the roller material control device 6 is fixed to the lower discharge end of the fixed carbonization furnace 4, and the reverse air shut-off fan 7 and the non-contact cooling screw conveyor 8 are sequentially fixed below the roller material control device 6; the ignition device 5 is fixed to the lower end of the fixed carbonization furnace 4.

[0042] In addition, the crusher, feeder, forward airlock fan 1, enclosed conveyor chain 2, material density control device 3, conveyor chain bed / grate, ignition device 5, roller material control device 6, reverse airlock fan 7, and non-contact cooling screw conveyor 8 are all connected to the control system. The control system can control the opening and closing of the crusher, feeder, forward airlock fan 1, enclosed conveyor chain 2, material density control device 3, conveyor chain bed / grate, ignition device 5, roller material control device 6, reverse airlock fan 7, and non-contact cooling screw conveyor 8 respectively. The level gauge 9 is used to detect the capacity of biomass or the position reached by the feed in the fixed carbonization furnace 4, and sends the detection signal to the control system when the biomass reaches the set capacity or set position. On the one hand, during the initial production, the control system controls the ignition device 5 to ignite according to the detection signal. On the other hand, after the initial ignition, the control system controls the opening and closing of the crusher, feeder, forward airlock 1, closed conveyor chain 2, material density control device 3, conveyor chain bed / grate, ignition device 5, roller material control device 6, reverse airlock 7 and non-contact cooling screw conveyor 8 according to the detection signal, thereby automatically controlling the continuous feeding, carbonization and discharge of biomass.

[0043] like Figure 1 As shown, the hard carbon production process specifically includes the following steps:

[0044] The biomass is pulverized using a pulverizer into particles with a diameter of 10-80mm to facilitate effective carbonization in subsequent processes. The pulverized biomass is then fed into a forward-facing airlock 1 by a feeder. The forward-facing airlock 1 ensures the biomass feedstock enters while isolating it from external oxygen. A closed conveyor chain 2 then feeds the biomass into a material density control device 3 for process density control. The material density control device 3 maintains the biomass at the required process density, ensuring it enters the fixed carbonization furnace 4 according to the manually set process density. Finally, a conveyor chain bed / grate feeds the biomass to the furnace according to the set process density. The biomass is fed into a fixed carbonization furnace 4. A level gauge 9 detects the volume of biomass within the furnace 4. When the level gauge 9 detects that the biomass has reached the set volume, the control system controls the ignition device 5 to ignite the biomass, raising its temperature to the set temperature for carbonization. A roller feed control device 6 sends the carbonized hard carbon precursor to a reverse airlock 7. The reverse airlock 7 ensures the hard carbon precursor is delivered out of the fixed carbonization furnace 4 while isolating it from external oxygen. A non-contact cooling screw conveyor 8 cools the hard carbon precursor to room temperature and simultaneously transports it to a closed storage tank for storage. Hard carbon is then prepared using the hard carbon precursor. Specifically, biomass begins to decompose and carbonize when heated to 300-450°C. The set temperature for carbonization in the fixed carbonization furnace 4 is 800-950°C. Decomposition and carbonization are completed when the set temperature is reached. Of course, the aforementioned set temperature can be adjusted according to the type of biomass.

[0045] It should be noted that after the biomass in the lower part of the fixed carbonization furnace 4 has completed carbonization, the control system can control the corresponding device to continuously feed the material, so that the production process can be carried out automatically and continuously. This can improve carbonization efficiency, reduce energy consumption, and reduce the intensity of manual labor.

[0046] In addition, the fixed carbonization furnace 4 is equipped with a temperature sensor connected to the control system. The control system can control the temperature inside the fixed carbonization furnace 4 according to the temperature sensor. For example, when the temperature inside the fixed carbonization furnace 4 exceeds the set temperature, the temperature can be reduced by increasing the amount of biomass.

[0047] According to a preferred embodiment of the present invention, such as Figure 6-7 The roller material control device 6 includes a drive mechanism 10 and two rotating rollers 11. Each of the two rotating rollers 11 is provided with a material-pushing piece 12, and the material-pushing pieces 12 on the two rotating rollers 11 are staggered. The drive mechanism 10 is connected to the control system and is used to control the rotating rollers 11 to rotate in opposite directions.

[0048] It should be noted that before the biomass is carbonized, the roller material control device 6 can serve as the bottom support for the biomass in the fixed carbonization furnace 4. After the biomass in the lower part of the fixed carbonization furnace 4 is carbonized into hard carbon precursor, the drive mechanism 10 is opened by the control system. The drive mechanism 10 controls the two rotating rollers 11 to rotate in opposite directions. The rotating rollers 11 can send the hard carbon precursor into the reverse airlock 7 through the feeding plate 12 on them.

[0049] The crusher, feeder, forward-facing airlock fan 1, enclosed conveyor chain 2, material density control device 3, conveyor chain bed / grate, level gauge 9, ignition device 5, reverse-facing airlock fan 7, and non-contact cooling screw conveyor 8 in this invention can all be implemented using existing conventional equipment. For details, please refer to [reference needed]. Figure 2-5 As shown in Figures 8-9.

[0050] Additionally, it should be noted that the material density control device 3 includes two symmetrically arranged, cyclically rotating chains on both sides of the conveyor chain bed / grate. Each chain has at least two transverse pressing plates fixed to it, facing the conveyor chain bed / grate, and the transverse pressing plates on the two chains are symmetrical. When the transverse pressing plates are driven by the chains to the side closest to the conveyor chain bed / grate, the opposite ends of the transverse pressing plates on both chains are located in the middle of the conveyor chain bed / grate. As the chains circulate, the transverse pressing plates are also driven to circulate downwards, thus controlling the density of the biomass. Depending on the type of biomass, in actual production, the speed of the transverse pressing plates can be adjusted by controlling the chain rotation speed, thereby adjusting the required density for different types of biomass and achieving optimal carbonization of the biomass.

[0051] Furthermore, the level gauge 9 in this invention is preferably a pendulum type structure, which mainly uses the reciprocating motion of the pendulum to detect the height of biomass entering the kiln. When the pendulum swings normally, it indicates that the biomass level in the fixed carbonization furnace 4 is insufficient, and a signal is transmitted to the control system to start feeding; when the pendulum stops due to the obstruction of biomass, it indicates that the biomass level in the fixed carbonization furnace 4 has reached the set level, and a signal is transmitted to the control system to stop feeding.

[0052] Finally, the applicant also used this invention to carbonize 1000 kg of biomass material. Testing showed that the carbonization time for this batch of biomass was 4.5–5 hours, and the final hard carbon precursor yielded 180–220 kg. However, because this invention can operate continuously and automatically without interruption, it significantly improves carbonization efficiency compared to existing technologies.

[0053] The above description is merely a specific embodiment of the present invention. Any feature disclosed in this specification may be replaced by other equivalent or similar features unless otherwise specified. All features or steps in the disclosed methods or processes may be combined in any way, except for mutually exclusive features and / or steps.

Claims

1. A process for producing biomass hard carbon for new energy batteries, characterized in that... Includes the following steps: After the biomass is crushed by the pulverizer, it is fed into the forward airlock (1) by the feeder. The biomass is then fed into the material density control device (3) by the closed conveyor chain (2) located below the forward airlock (1) to control the process density. The biomass is then fed into the fixed carbonization furnace (4) by the conveyor chain bed / grate. The biomass volume in the fixed carbonization furnace (4) is detected by the level gauge (9). When the biomass reaches the set volume, the ignition device (5) is used to ignite the biomass and raise its temperature to the set temperature. Carbonization → The carbonized hard carbon precursor is fed into the reverse airlock (7) by the roller material control device (6) → The hard carbon precursor is cooled to room temperature and transported to the closed storage tank by the non-contact cooling screw conveyor (8) set below the reverse airlock (7); and in the actual production process, the forward airlock (1) ensures the entry of biomass raw materials while isolating external oxygen, and the reverse airlock (7) ensures the hard carbon precursor is sent out of the fixed carbonization furnace while isolating external oxygen. The closed conveyor chain (2), material density control device (3), conveyor chain bed / grate and roller material control device (6) are connected in sequence between the forward air shut-off fan (1) and the reverse air shut-off fan (7), and both the forward air shut-off fan (1) and the reverse air shut-off fan (7) are in a closed state.

2. The biomass hard carbon production process for new energy batteries according to claim 1, characterized in that: The crusher, feeder, forward air shut-off fan (1), enclosed conveyor chain (2), material density control device (3), conveyor chain bed / grate, ignition device (5), roller material control device (6), reverse air shut-off fan (7), and non-contact cooling screw conveyor (8) are all controlled by the control system. The level gauge (9) sends a detection signal to the control system when it detects that the biomass has reached the set capacity. The control system is used to control ignition and control the continuous feeding, continuous carbonization, and continuous discharge of biomass according to the detection signal.

3. The biomass hard carbon production process for new energy batteries according to claim 1, characterized in that: The material density control device (3) is fixed at the upper feed end of the fixed carbonization furnace (4), the level gauge (9) is fixed on the upper part of the material density control device (3) and located on one side of the discharge end of the closed conveyor chain (2); the roller material control device (6) is fixed at the lower discharge end of the fixed carbonization furnace (4), the reverse air shut-off fan (7) and the non-contact cooling screw conveyor (8) are fixed below the roller material control device (6) in sequence; the ignition device (5) is fixed at the lower end of the fixed carbonization furnace (4).

4. The biomass hard carbon production process for new energy batteries according to claim 1, characterized in that: The roller material control device (6) includes a drive mechanism (10) and two rotating rollers (11). Both rotating rollers (11) are provided with material-pushing pieces (12), and the material-pushing pieces (12) on the two rotating rollers (11) are staggered. The drive mechanism (10) is connected to the control system and is used to control the rotating rollers (11) to rotate in opposite directions.

5. The biomass hard carbon production process for new energy batteries according to claim 1, characterized in that: The biomass, after being pulverized by a pulverizer, has a particle size of 10-80 mm.

6. The biomass hard carbon production process for new energy batteries according to claim 1, characterized in that: The set temperature for carbonizing the biomass in the fixed carbonization furnace (4) is 800-950℃.

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