Ultrahigh-temperature roller kiln and battery material sintering process

Abstract

The invention discloses an ultra-high-temperature roller kiln and a battery material sintering process, and belongs to the field of battery material sintering equipment.The ultra-high-temperature roller kiln comprises an inlet replacement chamber, a low-temperature section, a high-temperature section, a cooling section and an outlet replacement chamber which are sequentially connected, and the high-temperature section comprises a side heating element and a bearing furnace wall piece; the side heating elements are movably connected to the bearing furnace wall piece and extend into the two sides of the interior of the high-temperature section in a depth-adjustable mode, and the side heating elements with the insertion depth capable of being adjusted are arranged on the side faces of the high-temperature section, so that high-density heat input is achieved; the roller way empty kiln can stably operate at the ultra-high temperature of 1400 DEG C or above, and meanwhile the requirement for mass production of large-size roller way kilns is met.

Description

Technical Field

[0001] The present invention relates to the field of battery material sintering equipment, and particularly relates to an ultra-high temperature roller hearth kiln and a battery material sintering process. Background Art

[0002] The rapid development of the new energy vehicle and energy storage industries has driven the growing demand for high-performance batteries such as lithium-ion batteries and sodium-ion batteries. The production of battery anode and cathode materials (such as sodium battery anodes, hard carbon cathodes, etc.) requires high-temperature sintering processes, and the sintering temperature continues to increase with the material upgrade. Some battery materials need to be sintered in a kiln at a temperature above 1400°C, which poses higher requirements for the temperature upper limit, uniformity, and stability of the sintering equipment. The current mainstream high-temperature sintering equipment is the electric heating roller hearth kiln, and its heating elements have defects: for example, the long-term operating temperature of the electric heating alloy wire usually does not exceed 1000°C, which is only suitable for low-temperature sintering; while the silicon carbide rod can withstand higher temperatures, but its maximum withstand temperature is about 1300°C, still unable to meet the requirements of ultra-high temperature processes above 1400°C. In addition, although the silicon molybdenum rod can be used for high-temperature sintering at 1600°C, due to its high-temperature expansion characteristics, it cannot be installed horizontally, but needs to be installed perpendicular to the ground. Its heating area is only limited to the side of the furnace chamber, and it is difficult to form a uniform heating temperature field inside the overall furnace chamber. Therefore, its adaptability is poor, and it is only suitable for small test furnace heating and cannot be used in roller hearth kilns for mass production.

[0003] The large-scale production of lithium battery materials needs to meet the requirements of ultra-high temperature stability and temperature uniformity at the same time: on the one hand, it needs to operate at a temperature above 1400°C for a long time and the temperature control accuracy is controlled within ±5°C, and on the other hand, it needs to ensure that the temperature difference across the furnace section does not exceed 10°C to avoid fluctuations in material properties. However, the traditional roller hearth kiln is limited by the temperature upper limit of the heating element and the heating method. The application scenario of the side heating of the silicon molybdenum rod is limited to the test furnace, and it is difficult to achieve a uniform temperature field in a large-size kiln. In addition, during the mass production of battery materials, the disturbance of the furnace atmosphere caused by the continuous entry and exit of the saggers further exacerbates the temperature fluctuations in the furnace, resulting in the inability of existing equipment to balance high-temperature performance and mass production requirements. Therefore, there is a need for a roller hearth kiln structure with ultra-high temperature tolerance and uniform temperature inside the kiln. Summary of the Invention

[0004] One of the purposes of the present invention is to provide an ultra-high temperature roller hearth kiln, which solves the problems of insufficient heating temperature and uneven internal temperature distribution of the existing battery material roller hearth kiln using electric heating.

[0005] To achieve the above-mentioned invention purpose, the technical solutions adopted by the present invention are as follows:

[0006] An ultra-high temperature roller kiln comprises an inlet displacement chamber, a low temperature section, a high temperature section, a cooling section and an outlet displacement chamber which are connected in sequence, wherein the high temperature section comprises a side heating element and a supporting furnace wall member, wherein the side heating element is movably connected to the supporting furnace wall member, and the side heating element extends into both sides of the interior of the high temperature section in an adjustable depth;

[0007] The side heating element is a silicon-molybdenum rod, an electric heating element is arranged in the low-temperature section, a protective layer is arranged on the outer wall of the electric heating element, and the electric heating element is one of an electric heating wire or a silicon carbon rod. Different heating elements are arranged according to different temperature requirements of different sections to achieve ultra-high temperature heating and ensure the service life of the kiln;

[0008] The high temperature section includes an atmosphere system, which includes a left air inlet chamber, a bottom air inlet chamber and a right air inlet chamber. The left air inlet chamber is arranged on the left side wall of the high temperature section, the right air inlet chamber is arranged on the right side wall of the high temperature section, the bottom air inlet chamber is arranged at the bottom of the high temperature section, and the left air inlet chamber is arranged in the upper half of the high temperature section, and the right air inlet chamber is arranged in the lower half of the high temperature section. The bottom air inlet pipe on the bottom air inlet chamber faces the direction of the left air inlet chamber, so that a clockwise atmosphere circulation is formed in the high temperature section. Through the circulation of the atmosphere, the heat generated by the side heating element is evenly distributed to various places in the section to ensure the uniformity of the heating temperature. By arranging the side heating element with adjustable insertion depth on the side of the high temperature section, high-density heat input is achieved, and the ultra-high temperature and stable operation of the empty roller kiln above 1400°C is achieved, and at the same time, it meets the needs of mass production of large-size roller kilns.

[0009] Furthermore, the side heating element is an electric heating U-shaped tube, which has a simple structure and is easy to arrange.

[0010] Furthermore, an installation groove is provided on the supporting furnace wall member, and the installation groove is arranged to pass through the supporting furnace wall member. The installation groove is arranged as a longitudinal groove parallel to the moving direction of the sagger or a transverse groove perpendicular to the moving direction of the sagger. The side heating element passes through the installation groove and extends into the high-temperature section. According to different usage requirements, the side heating elements are arranged in different directions to meet the requirements of usage space or heat density.

[0011] Furthermore, a plurality of first heat insulation boards are provided in the low-temperature section, and the plurality of first heat insulation boards are arranged at the inlet and outlet and inside the low-temperature section to prevent the airflow in the low-temperature section, thereby realizing gradient temperature rise within the section, making the temperature control more accurate and the temperature during internal heating more uniform.

[0012] Furthermore, the high-temperature section includes a high-temperature heating chamber, and the cooling section includes a buffer chamber. Upper and lower heat insulation plates are provided at the connection between the buffer chamber and the high-temperature heating chamber to separate the upper and lower parts of the chamber, block the flow of the hot gas atmosphere in the buffer chamber, and prevent the high-temperature gas in the high-temperature section from flowing into the buffer chamber and the cooling section, thus avoiding affecting the cooling effect and improving the quality of the sintered battery material.

[0013] Preferably, the left air inlet chamber includes a left air inlet pipe and a left preheating chamber. One end of the left air inlet pipe is communicated with the left preheating chamber, and the other end is communicated with the inside of the high-temperature section. The left air inlet chamber has the same structure as the right air inlet chamber. The bottom air inlet chamber includes a bottom air inlet pipe and a bottom preheating chamber. One end of the bottom air inlet pipe is communicated with the bottom preheating chamber, and the other end is communicated with the inside of the high-temperature section, so as to actively circulate the atmosphere inside the section.

[0014] More preferably, it further includes a conveying system and an exhaust system. The conveying system includes a plurality of conveying rollers. An insulating coating is provided on the outer wall of the conveying rollers in the high-temperature section. A smoke exhaust port is provided at the top of the low-temperature section. The exhaust system is connected to the smoke exhaust port to increase the layout density of the side heating elements and discharge the waste gas generated by sintering.

[0015] The second object of the present invention is to provide a sintering process for battery material production, which solves the problem of uneven internal temperature distribution during high-temperature forming in the existing battery material sintering process.

[0016] To achieve the above-mentioned invention object, the technical solution adopted by the present invention is as follows:

[0017] A battery material sintering process is realized by the ultra-high temperature roller hearth kiln described above, and includes the following steps:

[0018] S1. The battery material is loaded in a sagger, and after the air is displaced in the inlet replacement chamber, it enters the low-temperature section for preheating;

[0019] S2. The waste gas generated by the battery material in the preheated sagger in the low-temperature section is discharged outward by the exhaust system on the low-temperature section. After the battery material is preheated to above 1250 °C, it is sent into the high-temperature section;

[0020] S3. Heat is generated by the side heating elements in the high-temperature section, and the heat is driven by the atmosphere system in the high-temperature section to circulate in the direction of the sagger's travel, uniformly heating the battery material to 1250 °C - 1600 °C, so that the battery material is sintered and formed at high temperature;

[0021] S4. The battery material after sintering and forming enters the cooling section and is cooled to 120°C - 130°C, and then is discharged after being replaced in the outlet replacement chamber. The battery material is uniformly sintered through a high-temperature kiln to achieve batch production of the battery material.

[0022] The beneficial effects of the present invention are as follows:

[0023] (1) The ultra-high temperature roller hearth kiln is provided with side heating elements in the high-temperature section. The side heating elements are inserted into the high-temperature section in a movable connection manner. The insertion depth of each side heating element is adjustable and evenly arranged, which solves the installation stability problem caused by the high-temperature expansion of silicon molybdenum rods, and breaks through the limitation of the traditional vertical hoisting method on the furnace chamber size, realizes ultra-high temperature stable operation above 1400°C, and at the same time meets the requirements of mass production of large-size roller hearth kilns.

[0024] (2) The low-temperature section of the ultra-high temperature roller hearth kiln is provided with electric heating elements. The electric heating elements are one of electric heating wires or silicon carbide rods, and the outer wall has a protective layer, which can prevent the corrosive gas generated by the battery material in the low-temperature section from damaging the electric heating elements. The side heating elements in the high-temperature section are silicon molybdenum rods, and the heating temperature is high, which can be used for high-temperature sintering of battery materials.

[0025] (3) The ultra-high temperature roller hearth kiln is provided with left and right air inlet chambers with left high and right low in the high-temperature section and a bottom air inlet chamber arranged at the bottom of the kiln. The air inlet direction of the bottom air inlet chamber faces the left air inlet chamber. When the three air inlet chambers intake air, it pushes the atmosphere in the kiln to rotate clockwise around the traveling direction of the sagger, so that the heat generated by the side heating elements can circulate in the kiln, and the heat generated by the side heating elements is evenly distributed into the kiln to heat the battery material in the sagger until the effect of uniform atmosphere temperature. Description of the Drawings

[0026] Figure 1 is a structural schematic diagram of the ultra-high temperature roller hearth kiln provided by the present invention;

[0027] Figure 2 is a structural diagram of the low-temperature section, high-temperature section and cooling section of the ultra-high temperature roller hearth kiln provided by the present invention;

[0028] Figure 3 is a sectional structural diagram of the low-temperature section of the ultra-high temperature roller hearth kiln provided by the present invention;

[0029] Figure 4 is a sectional structural diagram of the high-temperature section of the ultra-high temperature roller hearth kiln provided by the present invention;

[0030] Figure 5 is a sectional structural diagram of the cooling section of the ultra-high temperature roller hearth kiln provided by the present invention;

[0031] Figure 6 is Figure 4 a partial enlarged view of part A above;

[0032] Figure 7 is Figure 4 Partial enlarged view of part B above;

[0033] Figure 8 is Figure 4 Partial enlarged view of part C above;

[0034] Figure 9 is Figure 4 Partial enlarged view of part D above;

[0035] Figure 10 is Figure 4 Partial enlarged view of part E above;

[0036] Figure 11 The side heating element mode provided by the present invention Figure 1 ;

[0037] Figure 12 The side heating element mode provided by the present invention Figure 2 ;

[0038] Figure 13 Structural diagram of the inlet replacement chamber provided by the present invention;

[0039] Figure 14 Structural diagram of the fixed clamp installation provided by the present invention.

[0040] Reference numerals:

[0041] 1. Inlet replacement chamber; 11. Conveying system; 111. Conveying roller; 112. Insulating coating; 12. Replacement cavity; 13. First sealing door; 14. Second sealing door; 15. Third sealing door; 2. Low-temperature section; 21. First heat insulation board; 22. Smoke exhaust port; 23. Top sealing box; 24. Electric heating element; 25. Bottom air inlet device; 26. Heating box sealing cavity; 27. First transmission sealing cavity; 28. Side air inlet device; 3. High-temperature section; 31. Second heat insulation board; 32. High-temperature heating chamber; 33. Atmosphere system; 34. Right air inlet chamber; 341. Right air inlet pipe; 342. Right preheating chamber; 35. Second transmission sealing cavity; 36. Left air inlet chamber; 361. Left air inlet pipe; 362. Left preheating chamber; 37. Side heating element; 371. Heat preservation part; 3711. Installation groove; 372. Extension part; 373. Furnace wall supporting part; 38. Bottom air inlet chamber; 381. Bottom air inlet pipe; 382. Bottom preheating chamber; 4. Cooling section; 41. Bottom air injection device; 42. Heat discharge port; 43. Buffer chamber; 431. Upper heat insulation board; 432. Lower heat insulation board; 44. Heat exchange tube; 5. Outlet replacement chamber; 6. Smoke exhaust system; 7. Heat extraction system; 8. Saggar. Specific embodiments

[0042] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0043] Embodiment 1

[0044] As Figures 1 - 14 shown, this embodiment discloses an ultra-high temperature roller hearth kiln, which includes an inlet replacement chamber 1, a low temperature section 2, a high temperature section 3, a cooling section 4, and an outlet replacement chamber 5 connected in sequence. The high temperature section 3 includes side heating elements 37 and a supporting furnace wall member 373. The side heating elements 37 are movably connected to the supporting furnace wall member 373, and the side heating elements 37 are inserted into the two sides inside the high temperature section 3 with adjustable depth. A plurality of side heating elements 37 are evenly arranged at intervals on both sides of the high temperature section 3. The battery materials entering the high temperature section 3 are heated by heating air and thermal radiation. The inserted depth of each side heating element 37 is adjustable, which solves the installation stability problem caused by the high temperature expansion of silicon molybdenum rods, and has a higher layout density, realizing stable operation at ultra-high temperatures above 1400°C.

[0045] Among them, the high temperature section 3 includes an atmosphere system 33. The atmosphere system 33 includes a left air inlet chamber 36, a bottom air inlet chamber 38, and a right air inlet chamber 34. The left air inlet chamber 36 is arranged on the left side wall of the high temperature section 3, the right air inlet chamber 34 is arranged on the right side wall of the high temperature section 3, the bottom air inlet chamber 38 is arranged at the bottom of the high temperature section 3, and the left air inlet chamber 36 is arranged in the upper half of the high temperature section 3, the right air inlet chamber 34 is arranged in the lower half of the high temperature section 3. The bottom air inlet pipe 381 on the bottom air inlet chamber 38 faces the direction of the left air inlet chamber 36, so that a clockwise atmosphere circulation is formed in the high temperature section 3. According to different specific situations, the left air inlet chamber 36 can be arranged in the lower part of the high temperature section 3, the right air inlet chamber 34 can be arranged in the lower part of the high temperature section 3, and the bottom air inlet chamber 38 faces the right air inlet chamber 34, realizing the counterclockwise circulation of the internal high temperature atmosphere around the sagger 8. The heat generated by the side heating elements 37 is evenly distributed into the high temperature section 3 through the blown atmosphere, and a stable and uniform high temperature environment is formed in the entire high temperature section 3. The side heating elements 37 vertically suspended on both sides provide heat, and the battery materials are heated at ultra-high temperatures by radiation and convection.

[0046] Preferably, a fixing clip is provided at the end of the side heating element 37. The fixing clip can slide relative to the side heating element 37. The fixing clip is provided with bolts for applying the clamping force to clamp the side heating element 37. The fixing clip is connected to the supporting furnace wall member 373 for adjusting the depth of the side heating element 37 entering the kiln.

[0047] Preferably, the side heating element 37 extends vertically into the high-temperature section 3, which can increase the layout density of the side heating element 37.

[0048] Furthermore, the side heating element 37 is an electrically heated U-shaped tube. The U-shaped tube has a simple structure and a large heating area, which is convenient for installation.

[0049] Among them, the side heating element 37 is a silicon molybdenum rod. An electric heating element 24 is provided in the low-temperature section 2. A protective layer is provided on the outer wall of the electric heating element 24. The electric heating element 24 is one of an electric heating wire or a silicon carbide rod. The electric heating wire and the silicon carbide rod are suitable for heating below 1250°C, and the silicon molybdenum rod is suitable for heating above 1250°C. By reasonably arranging the spacing of the heating elements, the stable operation of the heating elements is ensured. By using the electric heating element 24 and the side heating element 37 in different zones, the purpose of stably heating the battery material at a super high temperature of 1400°C is achieved, and the use of the electric heating alloy wire at a temperature exceeding 1000°C for a long time is avoided; the maximum tolerable temperature of the silicon carbide rod is about 1300°C, which cannot meet the requirements of the super high temperature sintering process above 1400°C. Although the silicon molybdenum rod can withstand high-temperature sintering at 1600°C, due to its high-temperature expansion characteristics, it should be avoided to install it horizontally. By installing it perpendicular to the ground, the stability of the super high temperature heating is ensured.

[0050] Specifically, the electric heating element 24 is horizontally inserted from both side walls of the low-temperature section 2, and the electric heating elements 24 are respectively arranged above and below the sagger 8 for surrounding heating of the sagger 8.

[0051] Furthermore, an installation groove 3711 is provided on the supporting furnace wall member 373. The installation groove 3711 is arranged to penetrate the supporting furnace wall member 373 and is horizontal with the ground. The installation groove 3711 is arranged as a longitudinal groove parallel to the advancing direction of the sagger 8. The side heating element 37 passes through the installation groove 3711 and extends into the high-temperature section 3. The side heating element 37 can adjust the length extending into the high-temperature section 3 through the installation groove 3711, thereby ensuring the heating efficiency.

[0052] Preferably, the supporting furnace wall member 373 is a part of the kiln furnace wall, and the insertion of the side heating element 37 is realized by constructing a special-shaped structural member.

[0053] Preferably, it further includes an extension member 372 and a heat insulation member 371. One end of the extension member 372 is connected to the supporting furnace wall member 373, and the other end is connected to the heat insulation member 371. The side heating element 37 passes through the heat insulation member 371 and the extension member 372 and enters the high-temperature section 3 through the installation groove 3711. The heat insulation member 371 prevents the heat of the side heating element 37 from leaking from the tail, improving the energy utilization rate. The extension member 372 is used to adjust the length of the side heating element 37 extending into the high-temperature section 3 and surround the redundant part to prevent heat from escaping.

[0054] Furthermore, a plurality of first heat insulation plates 21 are provided in the low-temperature section 2. The plurality of first heat insulation plates 21 are arranged at the inlet, outlet and inside of the low-temperature section 2, which play a role in separating the low-temperature section 2 to reduce the temperature disturbance caused by the airflow. The hot gas atmosphere in the section is difficult to flow, making the temperature stable during heating and the heating curve of the battery material stable, facilitating the realization of gradient control of temperature rise, and helping to control the premature discharge of the waste gas generated by the battery material.

[0055] Preferably, the low-temperature section 2 includes a top sealing box 23 surrounding the furnace wall, a heating box sealing cavity 26 and a first transmission sealing cavity 27, which realize the sealing and heat insulation of the kiln, prevent heat leakage from the heating part and the transmission part, and improve the energy utilization rate.

[0056] Preferably, a bottom air inlet device 25 and a side air inlet device 28 are respectively provided at the bottom and side of the low-temperature section 2, which are used to input a hot atmosphere into the low-temperature section 2, can replace the waste gas generated in the section, and ensure the quality of the preheated battery material.

[0057] Furthermore, the high-temperature section 3 includes a high-temperature heating chamber 32, and the cooling section 4 includes a buffer chamber 43. Upper heat insulation plates 431 and lower heat insulation plates 432 are arranged at the connection between the buffer chamber 43 and the high-temperature heating chamber 32, which are used to separate and disconnect the upper and lower parts of the buffer chamber 43, prevent the hot gas in the high-temperature heating chamber 32 from entering the buffer chamber 43, control the cooling rate, and block the flow of high-temperature gas in the high-temperature section to the buffer chamber 43 and the cooling section 4, avoiding affecting the cooling effect.

[0058] Preferably, a sealing structure and a second transmission sealing cavity 35 are also provided outside the kiln of the high-temperature section 3, which are used to seal the kiln and isolate the transmission part, playing a heat preservation role.

[0059] Preferably, the left air inlet chamber 36 includes a left air inlet pipe 361 and a left preheating chamber 362. One end of the left air inlet pipe 361 is communicated with the left preheating chamber 362, and the other end is communicated with the inside of the high-temperature section 3. The left air inlet chamber 36 has the same structure as the right air inlet chamber 34. The right air inlet chamber 34 includes a right air inlet pipe 341 and a right preheating chamber 342. One end of the right air inlet pipe 341 is communicated with the right preheating chamber 342, and the other end is communicated with the high-temperature section 3. The bottom air inlet chamber 38 includes a bottom air inlet pipe 381 and a bottom preheating chamber 382. One end of the bottom air inlet pipe 381 is communicated with the bottom preheating chamber 382, and the other end is communicated with the inside of the high-temperature section 3. Each air inlet chamber preheats the input atmosphere through the preheating chamber and then blows it into the high-temperature section 3 through the air inlet pipe. By controlling the direction of the blown gas, the heat in each temperature zone in the high-temperature section 3 can be evenly distributed, and the hot air generated by the side heating elements 37 on both sides of the high-temperature section 3 is blown to realize the circulating heating of the high-temperature atmosphere.

[0060] More preferably, the inlet displacement chamber 1 comprises a displacement chamber 12 and a first sealing door 13, a second sealing door 14 and a third sealing door 15 which are sequentially telescopically arranged along the length direction of the displacement chamber 12. The structure of the inlet displacement chamber 1 is the same as that of the outlet displacement chamber 5. The sagger 8 enters the displacement chamber 12 through the first sealing door 13. The first sealing door 13 is closed to form an enclosed space. Inert gas is blown into the displacement chamber 12 to replace the air, thereby preventing the air from following the sagger 8 into the interior of the kiln and causing oxidation of the battery material. The second sealing door 14 and the third sealing door 15 are opened sequentially to separate the environment inside the kiln from the external environment, thereby preventing heat leakage during feeding and saving energy.

[0061] Preferably, it also includes a conveying system 11 and a smoke exhaust system 6. The conveying system 11 includes a plurality of conveying rollers 111. An insulating coating 112 is provided on the outer wall of the conveying roller 111 in the high-temperature section 3 to prevent the side heating element 37 from being too close to the conveying roller 111 and generating an arc. The insulating coating 112 can increase the length of the side heating element 37 entering the high-temperature section 3, thereby increasing the energy density of heating and achieving the effect of increasing the upper limit of temperature rise. A smoke exhaust port 22 is provided on the top of the low-temperature section 2, and the smoke exhaust system 6 is connected to the smoke exhaust port 22. When the low-temperature section 2 preheats the battery material in the sagger 8, the battery material will generate exhaust gas when heated, and the exhaust gas will corrode the inside of the kiln. The outer layer of the electric heating element 24 is covered with a protective layer, and the protective layer is made of quartz tube or ceramic tube to prevent exhaust gas corrosion. After the exhaust gas is generated, it is input into the smoke exhaust system 6 through the smoke exhaust port 22. The smoke exhaust system 6 performs harmless treatment on the exhaust gas and then discharges it to the outside.

[0062] Preferably, a heat exchange tube 44 is provided in the cooling section 4, and the heat exchange tube 44 is horizontally inserted into the kiln. The heat exchange tube 44 is filled with a heat exchange medium to exchange the heat in the cooling section 4 to the outside through contact until the cooling effect is achieved.

[0063] Preferably, a heat extraction system 7 is provided on the cooling section 4 , and the heat extraction system 7 extracts hot air from the heat exhaust port 42 through a fan to reduce the temperature in the cooling section 4 .

[0064] Preferably, a bottom aeration device 41 is provided at the bottom of the cooling section 4 , and the bottom aeration device 41 inputs cooling gas into the cooling section 4 to accelerate the cooling of the sagger 8 .

[0065] Preferably, a second heat insulation board 31 is provided at one end of the high temperature section 3 opposite to the low temperature section 2 to prevent the temperature atmosphere in the low temperature section 2 from entering the high temperature section 3 and causing temperature fluctuations in the high temperature section 3 .

[0066] Embodiment 2

[0067] See also Figure 11 and Figure 12, this embodiment discloses an ultra-high temperature roller hearth kiln. Its installation groove 3711 is arranged as a transverse groove perpendicular to the advancing direction of the sagger 8. The side heating element 37 passes through the installation groove 3711 and extends into the high-temperature section 3. By reducing the longitudinal space occupation of the side heating element 37 in the longitudinal direction of the kiln, the arrangement density of the side heating element 37 is increased, thereby increasing the heating rate and the upper limit of the heating temperature, and further improving the production efficiency of the kiln. The side heating element 37 uses a silicon molybdenum rod for heating, which can provide more heat to the sagger 8, and a reasonable distribution of the spacing can avoid the occurrence of arc phenomenon of the silicon molybdenum rod.

[0068] Embodiment III

[0069] This embodiment also discloses a battery material sintering process implemented by an ultra-high temperature roller hearth kiln, including the following steps:

[0070] S1. The battery material is loaded by the sagger 8, the air is discharged through the inlet replacement chamber 1, and then enters the low-temperature section 2 for preheating.

[0071] S2. The waste gas generated by preheating the battery material in the sagger 8 in the low-temperature section 2 is discharged outward by the smoke exhaust system 6 on the low-temperature section 2. After the battery material is preheated to above 1250 °C, it is sent into the high-temperature section 3.

[0072] S3. The high-temperature section 3 generates heat by the side heating element 37, and the heat is driven by the atmosphere system 33 in the high-temperature section 3 to circulate around the advancing direction of the sagger 8, uniformly heating the battery material to 1250 °C - 1600 °C, so that the battery material is sintered and formed at high temperature.

[0073] S4. The sintered and formed battery material enters the cooling section 4 and is cooled to 120 °C - 130 °C, and then is discharged after being replaced in the outlet replacement chamber 5. The battery material in the outlet replacement chamber 5 is further reduced to 80 °C - 90 °C.

[0074] The specific working process of this ultra-high temperature roller hearth kiln for battery materials is as follows:

[0075] After the battery material is loaded into the sagger 8, it enters the inlet replacement chamber 1. The first sealing door 13, the second sealing door 14, and the third sealing door 15 on the inlet replacement chamber 1 are opened in sequence to separate the replacement chamber 12 from the external environment, and the replacement of air is achieved by injecting inert gas. After the replacement is completed, the sagger 8 enters the low-temperature section 2. The electric heating element 24 in the low-temperature section 2 heats the sagger 8. The waste gas generated after the battery material is preheated is processed by the exhaust system 6 on the exhaust port 22 and discharged outwards. When heating, the first heat insulation board 21 divides the low-temperature section 2 into multiple shorter temperature zones to ensure that the heating temperature rise of the sagger 8 heated in the low-temperature section 2 is evenly transitioned and the temperature is stable during heating, and the heating temperature is controlled more accurately. When the temperature is heated to 1000°C - 1250°C, the sagger 8 enters the high-temperature section 3 from the low-temperature section 2. Heat is generated by the side heating element 37 in the high-temperature section 3 for heating. The second heat insulation board 31 in the high-temperature section 3 is opened. When heating, the left air inlet chamber 36, the right air inlet chamber 34, and the bottom air inlet chamber 38 on the atmosphere system 33 are opened to blow in hot air, so that the hot atmosphere in the high-temperature section 3 rotates around the sagger 8, evenly distributing the heat generated by the side heating element 37 to achieve uniform heating of the sagger 8. The sagger 8 is sintered and formed within the temperature range of 1250°C - 1600°C. After the sintering is completed, the sagger 8 enters the buffer chamber 43 in the cooling section 4. The upper heat insulation board 431 and the lower heat insulation board 432 in the buffer chamber 43 are opened to prevent hot air from entering the cooling section 4. The heat exchange tube 44 in the cooling section 4 exchanges the heat in the sagger 8, and the heat extraction system 7 extracts the hot air atmosphere in the cooling section 4 from the heat discharge port 42 on the cooling section 4. After the sagger 8 is cooled to the predetermined temperature, the sagger 8 is sent out of the kiln furnace after being replaced by the outlet replacement chamber 5.

[0076] Based on the disclosure and teachings of the above specification, those skilled in the art to which the present invention pertains can also make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for convenience of description and do not constitute any limitation to the present invention.

Claims

1. A super-high-temperature roller hearth kiln, comprising an inlet replacement chamber (1), a low-temperature section (2), a high-temperature section (3), a cooling section (4) and an outlet replacement chamber (5) connected in sequence, characterized in that: The high-temperature section (3) includes side heating elements (37) and a furnace wall supporting member (373). The side heating elements (37) are movably connected to the furnace wall supporting member (373), and the side heating elements (37) extend into both sides inside the high-temperature section (3) with adjustable depth. The side heating elements (37) are silicon molybdenum rods. An electric heating element (24) is provided inside the low-temperature section (2). A protective layer is provided on the outer wall of the electric heating element (24). The electric heating element (24) is one of an electric heating wire or a silicon carbide rod. The high-temperature section (3) includes an atmosphere system (33). The atmosphere system (33) includes a left air inlet chamber (36), a bottom air inlet chamber (38), and a right air inlet chamber (34). The left air inlet chamber (36) is provided on the left side wall of the high-temperature section (3). The right air inlet chamber (34) is provided on the right side wall of the high-temperature section (3). The bottom air inlet chamber (38) is provided at the bottom of the high-temperature section (3). The left air inlet chamber (36) is provided in the upper half of the high-temperature section (3). The right air inlet chamber (34) is provided in the lower half of the high-temperature section (3). The bottom air inlet pipe (381) on the bottom air inlet chamber (38) faces the direction of the left air inlet chamber (36), so that a clockwise atmosphere circulation is formed inside the high-temperature section (3).

2. The ultra-high temperature roller hearth kiln according to claim 1, characterized in that: The side heating elements (37) are electric heating U-shaped tubes.

3. The ultra-high temperature roller hearth kiln according to claim 1, characterized in that: The furnace wall supporting member (373) is provided with an installation groove (3711). The installation groove (3711) is arranged to penetrate through the furnace wall supporting member (373). The installation groove (3711) is arranged as a longitudinal groove parallel to the traveling direction of the sagger (8) or a transverse groove perpendicular to the traveling direction of the sagger (8). The side heating elements (37) pass through the installation groove (3711) and extend into the high-temperature section (3).

4. The ultra-high temperature roller hearth kiln according to any one of claims 1-3, characterized in that: A plurality of first heat insulation plates (21) are provided inside the low-temperature section (2). The plurality of first heat insulation plates (21) are provided at the inlet and outlet of the low-temperature section (2) and inside, to prevent the air flow inside the low-temperature section (2) from flowing.

5. The ultra-high temperature roller hearth kiln according to claim 1, characterized in that: The high-temperature section (3) includes a high-temperature heating chamber (32). The cooling section (4) includes a buffer chamber (43). Upper and lower heat insulation plates (431) and (432) are provided at the connection between the buffer chamber (43) and the high-temperature heating chamber (32) to separate the upper and lower parts of the buffer chamber (43).

6. The ultra-high temperature roller hearth kiln according to claim 1, characterized in that: The left air inlet chamber (36) includes a left air inlet pipe (361) and a left preheating chamber (362). One end of the left air inlet pipe (361) communicates with the left preheating chamber (362), and the other end communicates with the interior of the high-temperature section (3). The left air inlet chamber (36) has the same structure as the right air inlet chamber (34). The bottom air inlet chamber (38) includes a bottom air inlet pipe (381) and a bottom preheating chamber (382). One end of the bottom air inlet pipe (381) communicates with the bottom preheating chamber (382), and the other end communicates with the interior of the high-temperature section (3).

7. The ultra-high temperature roller hearth kiln according to any one of claims 1-3, characterized in that: It further includes a conveying system (11) and a smoke exhaust system (6). The conveying system (11) includes a plurality of conveying rollers (111). An insulating coating (112) is provided on the outer wall of the conveying rollers (111) in the high-temperature section (3). A smoke exhaust port (22) is provided at the top of the low-temperature section (2). The smoke exhaust system (6) is connected to the smoke exhaust port (22).

8. A sintering process for battery materials, characterized in that, Implemented by the ultra-high temperature roller hearth kiln according to any one of claims 1-7, including the following steps: S1. The battery material is loaded by the sagger (8), and after the air is discharged through the inlet replacement chamber (1), it enters the low-temperature section (2) for preheating; S2. The waste gas generated by preheating the battery material in the sagger (8) in the low-temperature section (2) is discharged outward by the smoke exhaust system (6) on the low-temperature section (2). After the battery material is preheated to above 1250 °C, it is sent into the high-temperature section (3); S3. Heat is generated by the side heating element (37) in the high-temperature section (3), and the heat is driven by the atmosphere system (33) in the high-temperature section (3) to circulate in the direction of the travel of the sagger (8), and the battery material is uniformly heated to 1250 °C - 1600 °C, so that the battery material is sintered and formed at high temperature; S4. The sintered and formed battery material enters the cooling section (4) and is cooled to 120 °C - 130 °C, and then is discharged from the furnace after being replaced by the outlet replacement chamber (5).

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