Rotary kiln and lithium ore pretreatment plant

Abstract

This utility model discloses a rotary kiln and lithium ore pretreatment equipment, solving the technical problem of improving the energy utilization efficiency of rotary kilns. It includes: a cylinder with a feed end at one end and a discharge end at the other, forming a material flow channel between the feed and discharge ends; a jacket fitted onto the outside of the cylinder, with a heating airflow channel formed between the side wall of the jacket and the side wall of the cylinder; a first partition separating the heating airflow channel between the jacket and the cylinder to form different first heating sections distributed along the length of the cylinder; a heating airflow temperature distribution gradient between the different first heating sections, decreasing sequentially from the discharge end to the feed end along the length of the cylinder; the first heating section closest to the discharge end is connected to the main heating airflow inlet, and the first heating section closest to the feed end is connected to the main heating airflow outlet; adjacent first heating sections are connected in series by heating airflow ducts disposed on the outside of the jacket. This achieves precise control of the heating airflow temperature distribution gradient.

Description

Technical Field

[0001] This utility model relates to a rotary kiln and lithium ore pretreatment equipment. Background Technology

[0002] The principle of lithium extraction from lithium ore using the sulfuric acid process is to utilize the oxidation reaction of sulfuric acid with the metals in the lithium ore to generate soluble sulfates, resulting in acidified clinker. After leaching and impurity removal, the acidified clinker undergoes lithium precipitation to obtain battery-grade lithium carbonate. Before the lithium ore reacts with sulfuric acid (acidification), pretreatment of the lithium ore is necessary. Currently, the pretreatment of lithium ore typically involves roasting crushed and dried lithium ore in a rotary kiln. The main purpose of roasting is to loosen the structure of the lithium ore and remove fluorides.

[0003] A traditional jacketed rotary kiln consists of a cylinder and a jacket fitted around the outside of the cylinder. One end of the cylinder is the feed end, and the other end is the discharge end, forming a material flow channel between them. A heating gas flow channel is formed between the jacket and the cylinder for heating the material inside the cylinder. The heating gas typically enters the heating gas flow channel from one end of the jacket (usually near the feed end of the cylinder), then flows along the entire heating gas flow channel before exiting from the other end of the jacket (usually near the discharge end of the cylinder).

[0004] The inventors discovered that because the heating airflow channel is a single, continuous space, the temperature distribution along the length of the cylinder is difficult to control precisely. This temperature distribution characteristic makes it difficult to accurately manage the heating process of lithium ore within the rotary kiln, affecting the pretreatment effect and energy utilization efficiency. Utility Model Content

[0005] The purpose of this utility model is to provide a rotary kiln and lithium ore pretreatment equipment to solve the technical problem of improving the energy utilization efficiency of rotary kilns.

[0006] In a first aspect, a rotary kiln is provided, comprising: a cylinder, one end of which is a feed end and the other end of which is a discharge end, wherein a material flow channel is formed between the feed end and the discharge end; a jacket, fitted onto the outside of the cylinder, wherein a heating airflow channel is formed between the side wall of the jacket and the side wall of the cylinder; the heating airflow channel is separated between the jacket and the cylinder by a first partition plate to form different first heating sections distributed along the length direction of the cylinder; and the heating airflow temperature distribution gradient between the different first heating sections decreases sequentially from the discharge end to the feed end along the length direction of the cylinder; the first heating section closest to the discharge end is connected to a total heating airflow inlet, and the first heating section closest to the feed end is connected to a total heating airflow outlet; adjacent first heating sections are connected in series by a heating airflow duct disposed on the outside of the jacket or a heating airflow through-plate channel disposed on the first partition plate between the adjacent first heating sections.

[0007] As an optimization and / or instantiation of the above-mentioned rotary kiln, further: at least one of the first heating sections is separated from the cylinder by a second partition to form different second heating sections, and these different second heating sections are used to heat different parts of the cylinder.

[0008] As an optimization and / or instantiation of the above-mentioned rotary kiln, further: at least two second baffles are provided in the at least one first heating section, which are spaced apart along the length direction of the cylinder. Each second baffle separates the at least one first heating section into different second heating sections distributed along the length direction of the cylinder. These different second heating sections are respectively connected to the same heating air inlet and the same heating air outlet.

[0009] As an optimization and / or instantiation of the above-mentioned rotary kiln, further: each of the second baffles provided in the at least one first heating section is fixed to the outside of the cylinder and also serves as a cylinder reinforcing rib, and an air passage gap is left between these cylinder reinforcing ribs and the side wall of the jacket.

[0010] As an optimization and / or instantiation of the above-mentioned rotary kiln, further: the first partition is fixed to the outside of the cylinder or to the inside of the jacket, and also serves as a cylinder guide plate; when the first partition is fixed to the outside of the cylinder, a dynamic sealing structure is provided between the outer edge of the first partition and the jacket; when the first partition is fixed to the inside of the jacket, a dynamic sealing structure is provided between the inner edge of the first partition and the cylinder.

[0011] As an optimization and / or instantiation of the above-mentioned rotary kiln, further: the dynamic sealing structure includes graphite sealing lubrication support structures located on both sides of the outer or inner edge of the corresponding first partition.

[0012] Secondly, a lithium ore pretreatment device is provided, which employs the rotary kiln described in the first aspect above.

[0013] As an optimization and / or instantiation of the aforementioned lithium ore pretreatment equipment, it further includes a hot blast stove, the exhaust port of which is connected to the inlet of the total heating airflow.

[0014] As an optimization and / or instantiation of the above-mentioned lithium ore pretreatment equipment, it is further configured such that the temperature at the inlet of the total heating airflow connected to the first heating section closest to the discharge end is 1050℃±20℃, and the temperature at the outlet of the heating airflow connected to the first heating section closest to the discharge end is 930℃±20℃.

[0015] As an optimization and / or instantiation of the above-mentioned lithium ore pretreatment equipment, it is further configured such that the temperature at the outlet of the total heating gas flow connected to the first heating section closest to the feed end is 450℃±50℃.

[0016] This utility model discloses a rotary kiln and lithium ore pretreatment equipment. By setting a first partition between the jacket and the cylinder, the heating airflow channel is divided into different first heating sections distributed along the length of the cylinder. The temperature distribution gradient of the heating airflow between these different first heating sections decreases sequentially from the discharge end to the feed end along the length of the cylinder. At the same time, the first heating section closest to the discharge end is connected to the main heating airflow inlet, and the first heating section closest to the feed end is connected to the main heating airflow outlet. Adjacent first heating sections are connected in series through the heating airflow duct outside the jacket or the heating airflow through-plate channel on the first partition. This achieves precise control of the heating airflow temperature distribution gradient, making the heating process of lithium ore in the rotary kiln more precise and controllable, improving the lithium ore pretreatment effect and energy utilization efficiency.

[0017] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Additional aspects and advantages provided by the present invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the rotary kiln (after the cylinder is made transparent) according to an embodiment of the present utility model.

[0019] Figure 2 for Figure 1 A partial view of the graphite sealing and lubrication support structure.

[0020] The following are marked in the figure: cylinder 1, feed end 11, discharge end 12, jacket 2, first partition 3, heating airflow duct 4, second partition 5, total heating airflow inlet 61, total heating airflow outlet 62, and graphite sealing and lubrication support structure 7. Detailed Implementation

[0021] The present invention will now be clearly and completely described in conjunction with the accompanying drawings. Those skilled in the art will be able to implement the present invention based on these descriptions. Before describing the present invention in conjunction with the accompanying drawings, it should be particularly noted that:

[0022] The technical solutions and features provided in the various sections, including the following description, can be combined with each other without conflict. Furthermore, where possible, these technical solutions, features, and related combinations can be given specific technical subject matter and protected by relevant patents.

[0023] The embodiments of the present invention described below are generally only some embodiments and not all embodiments. Based on these embodiments, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of patent protection.

[0024] The terms "comprising," "including," "having," and any variations thereof in this specification, the corresponding claims, and related sections are intended to cover non-exclusive inclusion. Other related terms and units can be reasonably interpreted based on the relevant content provided in this specification.

[0025] Figure 1 This is a schematic diagram of the structure of the rotary kiln (after the cylinder is made transparent) according to an embodiment of the present utility model. Figure 2 for Figure 1 A partial view of the graphite sealing and lubrication support structure.

[0026] like Figure 1 As shown, the rotary kiln of this embodiment includes a cylinder 1 and a jacket 2. One end of the cylinder 1 is a feed end 11, and the other end is a discharge end 12, forming a material flow channel between the feed end 11 and the discharge end 12. The jacket 2 is fitted onto the outside of the cylinder 1, and a heating airflow channel is formed between the side wall of the jacket 2 and the side wall of the cylinder 1. The heating airflow channel is separated between the jacket 2 and the cylinder 1 by a first partition 3, forming different first heating sections distributed along the length direction of the cylinder 1.

[0027] In this embodiment, the rotary kiln is equipped with two first heating sections: one near the discharge end 12 and the other near the feed end 11. The temperature distribution gradient of the heating gas flow between the different first heating sections decreases sequentially from the discharge end 12 to the feed end 11 along the length of the cylinder 1. This design meets the process requirements of lithium ore roasting pretreatment and makes the temperature distribution more reasonable.

[0028] The first heating section closest to the discharge end 12 is connected to the main heating air inlet 61, and the first heating section closest to the feed end 11 is connected to the main heating air outlet 62. Adjacent first heating sections are connected in series by heating air ducts 4 located on the outside of the jacket 2. The heating air ducts 4 connect the outlet of the upstream first heating section to the inlet of the downstream first heating section, so that the heating air can flow through each first heating section sequentially along a predetermined path.

[0029] In this embodiment, the jacket 2 corresponding to the first heating section near the discharge end 12 is separated from the cylinder 1 by a second partition 5 to form different second heating sections. These different second heating sections are used to heat different parts of the cylinder 1 in the first heating section, thereby achieving more precise temperature control.

[0030] Specifically, a plurality of second baffles 5 are arranged at intervals along the length of the cylinder 1 in the first heating section near the discharge end 12. Each second baffle 5 divides the first heating section into different second heating sections distributed along the length of the cylinder 1. These different second heating sections are respectively connected to the same heating air inlet and the same heating air outlet. This design can achieve more precise temperature control in the discharge end area while maintaining the overall temperature gradient.

[0031] The second baffles 5, located in the first heating section near the discharge end 12, are fixed to the outside of the cylinder 1 and also serve as cylinder reinforcing ribs. A ventilation gap is left between these cylinder reinforcing ribs and the side wall of the jacket 2. This design not only enhances the structural stability of the cylinder 1 and prevents deformation of the cylinder 1 at high temperatures, but also ensures smooth flow of the heating airflow.

[0032] like Figure 1 and Figure 2 As shown, the first partition 3 is fixed to the outside of the cylinder 1 and also serves as a guide plate for the cylinder. Since the first partition 3 is fixed to the outside of the cylinder 1, a dynamic sealing structure is provided between the outer edge of the first partition 3 and the jacket 2. This dynamic sealing structure can effectively prevent the mixing of heating airflow between different first heating sections, while allowing the cylinder 1 to rotate freely within the jacket 2.

[0033] Figure 2 The dynamic sealing structure is shown in detail, which includes graphite sealing and lubrication support structures 7 located on both sides of the outer edge of the first partition 3. The graphite sealing and lubrication support structures 7 not only provide a good sealing effect, but also have a lubrication function, reducing the frictional resistance when the cylinder 1 rotates and extending the service life of the equipment.

[0034] In this embodiment, the rotary kiln serves as the core component of the lithium ore pretreatment equipment and is also used in conjunction with a hot blast stove. The exhaust port of the hot blast stove is connected to the main heating airflow inlet 61, providing a high-temperature heat source for the rotary kiln.

[0035] In practical applications, the lithium ore pretreatment equipment is configured such that the temperature at the main heating gas inlet 61, connected to the first heating section closest to the discharge end 12, is 1050℃±20℃, and the temperature at the heating gas outlet 62, connected to the first heating section closest to the discharge end 12, is 930℃±20℃. Simultaneously, the lithium ore pretreatment equipment is configured such that the temperature at the main heating gas outlet 62, connected to the first heating section closest to the feed end 11, is 450℃±50℃. This temperature setting meets the process requirements of lithium ore roasting pretreatment, ensuring both sufficient roasting effect and full utilization of the heat from the high-temperature gas emitted from the hot blast furnace.

[0036] Compared with traditional rotary kilns, the rotary kiln of this invention achieves precise control of the temperature distribution gradient of the heating airflow by setting different heating sections, which greatly improves energy utilization efficiency. At the same time, the design of the second baffle 5 as a reinforcing rib of the cylinder and the first baffle 3 as a guide plate of the cylinder achieves effective integration of structure and function, improving the structural stability and service life of the equipment.

[0037] The foregoing has described the relevant content of this utility model. Those skilled in the art will be able to implement this utility model based on these descriptions. All other embodiments obtained by those skilled in the art based on the foregoing content of this specification without inventive effort should fall within the scope of this utility model.

Claims

1. Rotary kiln, including: The cylinder has a feed end at one end and a discharge end at the other end, forming a material flow channel between the feed end and the discharge end; A jacket is fitted onto the outside of the cylinder, and a heating airflow channel is formed between the side wall of the jacket and the side wall of the cylinder; Its features are: The jacket and the cylinder are separated by a first partition to form different first heating sections distributed along the length of the cylinder; Furthermore, the temperature distribution gradient of the heating airflow between different first heating sections decreases sequentially from the discharge end to the feed end along the length direction of the cylinder. The first heating section closest to the discharge end is connected to the main heating airflow inlet, and the first heating section closest to the feed end is connected to the main heating airflow outlet; Adjacent first heating sections are connected in series via heating airflow ducts located on the outside of the jacket or heating airflow through-plate channels located on the first partition between the adjacent first heating sections.

2. The rotary kiln as described in claim 1, characterized in that: At least one of the first heating sections is separated from the cylinder by a second partition to form different second heating sections. These different second heating sections are used to heat different parts of the cylinder.

3. The rotary kiln as described in claim 2, characterized in that: The at least one first heating section is provided with at least two second partitions arranged at intervals along the length direction of the cylinder. Each second partition divides the at least one first heating section into different second heating sections distributed along the length direction of the cylinder. These different second heating sections are respectively connected to the same heating air inlet and the same heating air outlet.

4. The rotary kiln as described in claim 3, characterized in that: Each of the second baffles provided in the at least one first heating section is fixed to the outside of the cylinder and also serves as a cylinder reinforcement. A ventilation gap is left between these cylinder reinforcements and the side wall of the jacket.

5. The rotary kiln as described in any one of claims 1-4, characterized in that: The first partition is fixed to the outside of the cylinder or the inside of the jacket, and also serves as a guide plate for the cylinder. When the first partition is fixed to the outside of the cylinder, a dynamic sealing structure is provided between the outer edge of the first partition and the jacket. When the first partition is fixed to the inside of the jacket, a dynamic sealing structure is provided between the inner edge of the first partition and the cylinder.

6. The rotary kiln as described in claim 5, characterized in that: The dynamic sealing structure includes graphite sealing and lubrication support structures located on both sides of the outer or inner edge of the corresponding first partition.

7. Lithium ore pretreatment equipment, characterized in that: The rotary kiln described in any one of claims 1-6 is used.

8. The lithium ore pretreatment equipment as described in claim 7, characterized in that: It also includes a hot air furnace, the exhaust port of which is connected to the main heating airflow inlet.

9. The lithium ore pretreatment equipment as described in claim 8, characterized in that: It is configured such that the temperature at the inlet of the total heating airflow connected to the first heating section closest to the discharge end is 1050℃±20℃, and the temperature at the outlet of the heating airflow connected to the first heating section closest to the discharge end is 930℃±20℃.

10. The lithium ore pretreatment equipment as described in claim 9, characterized in that: It is configured such that the temperature at the outlet of the main heating airflow connected to the first heating section closest to the feed end is 450℃±50℃.

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