A pre-treatment rotary kiln for producing high purity lithium oxide

Abstract

The utility model provides a kind of pretreatment rotary kiln of production high-purity lithium oxide belongs to rotary kiln technical field, solve the problem that temperature control is more difficult in prior art. It includes at least two supports, the support is rotationally arranged with drum, and the both ends of drum are rotationally sealedly connected with first end cover and second end cover, heating cavity is arranged in the lateral wall of drum, and hot liquid inlet pipe is arranged at the axis of drum and penetrates first end cover, and first connecting pipe is communicated between one end of hot liquid inlet pipe and heating cavity, and jacket is sleeved on hot liquid inlet pipe, second connecting pipe is communicated between jacket and heating cavity, and hot liquid outlet pipe is connected by jacket and penetrates first end cover. Heating cavity is opened on the lateral wall of drum, and temperature-stable hot liquid is transported to heating cavity by hot liquid inlet pipe, then hot liquid is discharged from jacket, hot liquid outlet pipe and heating cavity, to realize the circulating heating of drum, to keep the temperature of lithium hydroxide in drum stable, to ensure the quality and performance of lithium hydroxide.

Description

Technical Field

[0001] This utility model belongs to the field of rotary kiln technology, specifically to a pretreatment rotary kiln for producing high-purity lithium oxide. Background Technology

[0002] A rotary kiln is a tilting, rotating cylindrical device that achieves calcination, drying, or chemical reactions through high-temperature countercurrent contact with materials. It is widely used in industries such as cement, metallurgy, chemicals, and environmental protection, and boasts advantages such as simple structure, strong adaptability, and large production capacity. In the continuous production process of high-purity lithium oxide using DBD (Dielectric Barrier Discharge) plasma technology, a rotary kiln is used to pre-treat crushed lithium hydroxide raw materials for drying. Removing free water from the lithium hydroxide raw material reduces the energy required for subsequent processing and decreases the water vapor content in the gaps between the plasma electrodes, thus lowering the probability of arc discharge between the electrodes.

[0003] Precise temperature control is crucial in the drying process of lithium hydroxide raw materials using a pretreatment rotary kiln. However, existing pretreatment rotary kilns present certain challenges in temperature control, and are prone to excessive temperature fluctuations. This can lead to overheating or undercooling of the lithium hydroxide, affecting product quality and performance. Utility Model Content

[0004] To address the aforementioned problems, the purpose of this utility model is to provide a pretreatment rotary kiln for producing high-purity lithium oxide. A heating chamber is opened on the side wall of the drum, and a hot liquid with a stable temperature is supplied to the heating chamber through a hot liquid inlet pipe. The hot liquid is then discharged from the heating chamber through the jacket and hot liquid outlet pipe, thereby realizing the circulation heating of the drum to maintain the stable temperature of lithium hydroxide inside the drum and ensure the quality and performance of lithium hydroxide.

[0005] The technical solution adopted in this utility model is as follows:

[0006] A pretreatment rotary kiln for producing high-purity lithium oxide includes at least two supports, on which a drum is rotatably mounted. A first end cover and a second end cover are rotatably and sealingly connected to both ends of the drum. A heating chamber is provided in the side wall of the drum. A hot liquid inlet pipe is provided at the center of the drum, extending through the first end cover. A first connecting pipe connects one end of the hot liquid inlet pipe to the heating chamber. A jacket is fitted on the hot liquid inlet pipe. A second connecting pipe connects the jacket to the heating chamber. The jacket extends through the first end cover and is connected to a hot liquid outlet pipe.

[0007] Preferably, the second end cap is provided with an inlet pipe for conveying thermal inert gas, and the first end cap is provided with an outlet pipe.

[0008] Preferably, a water vapor sensor is installed in the air outlet pipe.

[0009] Preferably, the second end cap is provided with a temperature sensor for detecting the temperature of lithium hydroxide.

[0010] Preferably, the inner wall of the roller is provided with several turning plates.

[0011] Preferably, the inner wall of the roller is provided with several spiral baffles.

[0012] Preferably, a drain pipe is provided at the bottom of the first end cap.

[0013] Preferably, the first end cap is provided with a feed pipe, and the second end cap is provided with a discharge pipe.

[0014] Preferably, the roller is inclined toward the discharge pipe.

[0015] Preferably, a toothed ring is fixedly sleeved on the roller, the toothed ring meshes with a gear, and the gear is connected to a fixed drive motor.

[0016] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model are:

[0017] A heating chamber is opened on the side wall of the drum. A hot liquid with a stable temperature is supplied to the heating chamber through a hot liquid inlet pipe. The hot liquid is then discharged from the heating chamber through the jacket and hot liquid outlet pipe, realizing the circulation heating of the drum to maintain the stable temperature of lithium hydroxide inside the drum and ensure the quality and performance of lithium hydroxide. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A three-dimensional structural schematic diagram provided for an embodiment of this utility model;

[0020] Figure 2 A three-dimensional structural schematic diagram from another perspective provided for an embodiment of this utility model;

[0021] Figure 3 This is a schematic diagram of the front cross-sectional structure provided for an embodiment of the present utility model;

[0022] Figure 4 for Figure 3 Enlarged structural diagram at point A in the middle.

[0023] Reference numerals: 1-Support; 2-Roller; 3-Fixing ring; 4-Gear ring; 5-Drive motor; 6-Gear; 7-Water vapor sensor; 8-Outlet pipe; 9-Feed pipe; 10-First end cap; 11-Jacket; 12-Hot liquid inlet pipe; 13-Hot liquid outlet pipe; 14-Drain pipe; 15-Second end cap; 16-Temperature sensor; 17-Outlet pipe; 18-Inlet pipe; 19-Screwing baffle; 20-Tilting plate; 21-Heating chamber; 22-First connecting pipe; 23-Roller; 24-Second connecting pipe. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0026] In the description of this utility model, it should be noted that if terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" appear to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use, they are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0027] The following is combined with Figures 1-4 This utility model will be described in detail.

[0028] Example

[0029] A pretreatment rotary kiln for producing high-purity lithium oxide includes at least two supports 1. A drum 2 is rotatably mounted on the supports 1. A first end cover 10 and a second end cover 15 are rotatably and sealingly connected to both ends of the drum 2. A heating chamber 21 is provided in the side wall of the drum 2. A hot liquid inlet pipe 12 is provided at the axis of the drum 2, penetrating through the first end cover 10. A first connecting pipe 22 is connected between one end of the hot liquid inlet pipe 12 and the heating chamber 21. A jacket 11 is fitted on the hot liquid inlet pipe 12. A second connecting pipe 24 is connected between the jacket 11 and the heating chamber 21. The jacket 11 penetrates through the first end cover 10 and is connected to a hot liquid outlet pipe 13.

[0030] The first end cap 10 and the second end cap 15 can be fixed to the ground or other stationary equipment via connecting rods or other structures, keeping them stationary. The jacket 11 is rotatably sealed to the first end cap 10, and the hot liquid inlet pipe 12 is connected to the corresponding pipe via a rotating joint. Hot liquid enters the hot liquid inlet pipe 12 and flows into the heating chamber 21 through the first connecting pipe 22. The heating chamber 21 discharges the used hot liquid into the jacket 11 through the second connecting pipe 24, and finally discharges it from the hot liquid outlet pipe 13. The hot liquid outlet pipe 13 is not connected to other pipes, thus ensuring that the hot liquid outlet pipe 13 can discharge hot liquid normally during the rotation of the jacket 11. Multiple first connecting pipes 22 and second connecting pipes 24 are evenly arranged along the radial direction of the roller 2 to ensure the uniform inflow or outflow of hot liquid into or out of the heating chamber 21.

[0031] Existing rotary kilns generate a large amount of water vapor during the drying process. If this water vapor cannot be effectively and promptly discharged, it will create a humid environment inside the kiln, affecting the drying effect and quality of lithium hydroxide. Furthermore, the water vapor may corrode the rotary kiln equipment, shortening its service life. Therefore, this application provides an inlet pipe 18 for conveying hot inert gas on the second end cover 15. The inlet pipe 18 is located at the axis of the second end cover 15, and an outlet pipe 8 is provided on the first end cover 10. The inert gas, pumped by an air pump, enters the drum 2 through the inlet pipe 18, carrying away the water vapor from the drum 2 through the outlet pipe 8. This timely discharge of water vapor ensures the drying effect and quality of lithium hydroxide. Simultaneously, the inert gas, after being heated during drying, reaches a certain temperature, further enhancing heat transfer efficiency and ensuring uniform heating of the lithium hydroxide during pretreatment, thus improving the stability of the lithium hydroxide quality.

[0032] In the pretreatment process, the flow rate of the inlet pipe 18 is slightly greater than that of the outlet pipe 8. Inert gas is continuously purged during both the pretreatment and drying processes of lithium hydroxide. The inert gas carrying water vapor passes through the heat exchanger and dehydration drying device of the cooling system, realizing the recycling of the inert gas, fully recovering the heat generated during the heating process, improving energy utilization efficiency, and reducing production costs. At the same time, maintaining the purging of inert gas during the discharge process not only prevents the oxidation of lithium hydroxide but also further utilizes the heat of the inert gas, reducing energy waste.

[0033] A water vapor sensor 7 is installed in the exhaust pipe 8. The water vapor sensor 7 can be an AHS01IB type water vapor sensor from Auson Electronics. The water vapor sensor 7 can monitor the content of water vapor discharged in real time. When no water vapor is detected, the surface lithium hydroxide drying is complete, and the discharge operation can be carried out.

[0034] The second end cap 15 is equipped with a temperature sensor 16 for detecting the temperature of lithium hydroxide. The temperature sensor 16 can detect the temperature of lithium hydroxide, ensuring that the temperature of lithium hydroxide does not exceed 110℃, thus guaranteeing the quality of lithium hydroxide. The dried lithium hydroxide is then transported to a lithium hydroxide temporary storage chamber, which is covered with insulation material. Combined with temperature monitoring during the drying process, this effectively prevents the lithium hydroxide from overheating or cooling, ensuring the stability of product quality.

[0035] In existing rotary kilns, the smooth inner wall of the drum 2 often results in poor tumbling of lithium hydroxide during the drying process, leading to limited contact area between the lithium hydroxide and the heating medium and low heat transfer efficiency. This not only affects the heating speed and uniformity of the lithium hydroxide but also prolongs the production cycle and reduces production efficiency. Therefore, this application provides several turning plates 20 and several swivel baffles 19 on the inner wall of the drum 2. The turning plates 20 and swivel baffles 19 work together to fully tumble the lithium hydroxide, increasing the contact area between the lithium hydroxide and the heating medium and improving heat transfer efficiency. This allows the lithium hydroxide to reach the required temperature more quickly during pretreatment, shortening the production cycle and improving production efficiency. The swivel baffles 19 have a helix angle of 15-40°, a protrusion height of 5-10 cm, and are arranged in 2-5 sets.

[0036] A drain pipe 14 is provided at the bottom of the first end cover 10. The drain pipe 14 is normally closed and is only opened when needed to discharge impurities from the roller 2.

[0037] The first end cap 10 is provided with a feed pipe 9, and the second end cap 15 is provided with a discharge pipe 17, which is located at the bottom of the second end cap 15. The feed pipe 9 is used to feed the crushed lithium hydroxide into the drum 2, and the dried lithium hydroxide is discharged from the drum 2 through the discharge pipe 17.

[0038] The roller 2 is inclined toward the discharge pipe 17. The inclination angle of the roller 2 is 5-10°; the two supports 1 are set at different heights to keep the roller 2 in an inclined state. A fixing ring 3 is fixedly sleeved on the roller 2, and two rollers 23 are rotatably installed in the support 1. The two rollers 23 cooperate with the fixing ring 3 to support the rotation of the roller 2.

[0039] A gear ring 4 is fixedly fitted on the drum 2, and a gear 6 meshes with the gear ring 4. The gear 6 is connected to a fixed drive motor 5. The drive motor 5 drives the gear 6 to rotate through its output shaft, and the gear 6 in turn drives the meshing gear ring 4 to rotate. The drum 2 rotates synchronously with the gear ring 4, realizing the operation of rolling and turning material drying.

[0040] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A pretreatment rotary kiln for producing high-purity lithium oxide, comprising at least two supports (1), wherein a drum (2) is rotatably mounted on each support (1), and a first end cap (10) and a second end cap (15) are respectively rotatably and sealingly connected to both ends of the drum (2), characterized in that, A heating chamber (21) is provided in the side wall of the drum (2). A hot liquid inlet pipe (12) is provided at the axis of the drum (2) and passes through the first end cover (10). A first connecting pipe (22) is connected between one end of the hot liquid inlet pipe (12) and the heating chamber (21). A jacket (11) is fitted on the hot liquid inlet pipe (12). A second connecting pipe (24) is connected between the jacket (11) and the heating chamber (21). The jacket (11) passes through the first end cover (10) and is connected to the hot liquid outlet pipe (13).

2. The pretreatment rotary kiln for producing high-purity lithium oxide according to claim 1, characterized in that, The second end cap (15) is provided with an inlet pipe (18) for conveying thermal inert gas, and the first end cap (10) is provided with an outlet pipe (8).

3. The pretreatment rotary kiln for producing high-purity lithium oxide according to claim 2, characterized in that, A water vapor sensor (7) is installed in the air outlet pipe (8).

4. The pretreatment rotary kiln for producing high-purity lithium oxide according to claim 1, characterized in that, The second end cap (15) is provided with a temperature sensor (16) for detecting the temperature of lithium hydroxide.

5. The pretreatment rotary kiln for producing high-purity lithium oxide according to claim 1, characterized in that, Several turning plates (20) are provided on the inner wall of the roller (2).

6. The pretreatment rotary kiln for producing high-purity lithium oxide according to claim 1, characterized in that, Several spiral baffles (19) are provided on the inner wall of the roller (2).

7. The pretreatment rotary kiln for producing high-purity lithium oxide according to claim 1, characterized in that, A drain pipe (14) is provided at the bottom of the first end cap (10).

8. The pretreatment rotary kiln for producing high-purity lithium oxide according to claim 1, characterized in that, The first end cap (10) is provided with a feed pipe (9), and the second end cap (15) is provided with a discharge pipe (17).

9. A pretreatment rotary kiln for producing high-purity lithium oxide according to claim 8, characterized in that, The roller (2) is inclined toward the discharge pipe (17).

10. A pretreatment rotary kiln for producing high-purity lithium oxide according to claim 1, characterized in that, A toothed ring (4) is fixedly sleeved on the roller (2), and a gear (6) meshes with the toothed ring (4). The gear (6) is connected to a fixed drive motor (5).

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