A reduction kiln for producing vanadium trioxide and a feeding operation method thereof

Abstract

The application provides a reduction kiln for vanadium trioxide production and a feeding operation method thereof, and is suitable for the technical field of chemical industry. The reduction kiln comprises a reduction cylinder, into which reduction gas is introduced; and a hearth which is sleeved outside the reduction cylinder; wherein a plurality of burners for heating the reduction cylinder are arranged inside the hearth; the burners are connected with compressed air and combustion gas, and the combustion gas can be coal gas; the hearth is sequentially provided with reduction points 1, 2, 3, 4 and 5 along the feeding direction of the reduction cylinder; a stock bin is used for adding raw materials to the reduction cylinder; a spiral feeding device for feeding the reduction cylinder is arranged on the stock bin; and a tank is used for collecting finished products produced by the reduction cylinder. The application effectively solves the problem of ring formation in the initial feeding stage of the reduction kiln, ensures smooth production, and reduces the labor intensity of cleaning the ring formation material of the reduction kiln.

Description

Technical Field

[0001] This invention relates to the field of chemical technology, specifically to a reduction kiln for the production of vanadium trioxide and its feeding operation method. Background Technology

[0002] Currently, the industrial production of vanadium trioxide (V₂O₃) mainly involves the dehydration, deammoniation, and reduction reactions of ammonium polyvanadate under high temperature and reducing atmosphere conditions. This process transforms vanadium from a high-valence oxide to a low-valence oxide, yielding vanadium trioxide as the final product. The main equipment is called a reduction kiln. Due to the large fluctuations in vanadium slag feed and the unique nature of the "calcification roasting-acid leaching" process, the intermediate product ammonium polyvanadate in the vanadium trioxide production process contains many impurities. Continuing to use the traditional sodium leaching process's reduction kiln feeding method easily leads to ring formation in the reduction kiln shell, affecting smooth production.

[0003] To address this technical problem, a reduction kiln for vanadium trioxide production and its feeding operation method are proposed. Summary of the Invention

[0004] The purpose of this invention is to provide a reduction kiln for vanadium trioxide production and its feeding operation method, so as to solve the problems mentioned in the background art.

[0005] According to the present invention, a reduction kiln for the production of vanadium trioxide is provided, comprising: The reduction cylinder is filled with reducing gas. The furnace chamber is fitted onto the outside of the reduction cylinder; The furnace chamber is equipped with multiple burners for heating the reduction cylinder; each burner is connected to compressed air and combustion gas, which can be coal gas; reduction points 1, 2, 3, 4 and 5 are arranged sequentially and at intervals along the material conveying direction of the reduction cylinder inside the furnace chamber for detecting and controlling the reduction temperature. A hopper is used to add raw materials to the reduction cylinder; the hopper is equipped with a screw feeder for feeding materials to the reduction cylinder; and a tank is used to collect the finished products produced by the reduction cylinder.

[0006] As a further embodiment of the present invention: the hopper and the tank are respectively located at both ends of the reduction cylinder.

[0007] As a further embodiment of the present invention, the reduction cylinder is arranged at an angle.

[0008] As a further aspect of the present invention, it also includes a cooling water tank, which is used to cool the packing area on the reduction cylinder.

[0009] As a further aspect of the present invention, it also includes an exhaust gas treatment device for purifying the exhaust gas discharged from the reduction cylinder.

[0010] As a further embodiment of the present invention: the exhaust gas treatment device includes a sealed water tank and an exhaust gas pipeline, the input end of the sealed water tank is connected to the inside of the reduction cylinder, the output end of the sealed water tank is connected to the input end of the exhaust gas pipeline, and the sealed water tank contains a purification medium.

[0011] As a further aspect of the present invention, a flue gas duct is also provided on the furnace.

[0012] To achieve the above objectives, the present invention provides another technical solution as follows: A method for feeding materials into a reduction kiln used in the production of vanadium trioxide, characterized by comprising the following steps: Adjust the air-coal ratio of the burners inside the furnace to raise the temperature of reduction point 1 to 500℃~750℃, the temperature of reduction point 2 to 600℃~800℃, the temperature of reduction points 3 and 4 to 700℃~900℃, and the temperature of reduction point 5 to 450℃~650℃. Adjust the flow rate of reducing gas input to reduction cylinder 1 to 200-400 m³ / h; Once the reduction temperature and reducing gas flow rate inside the furnace reach the required levels, control the feed rate of the silo to 600–900 kg / h. Start feeding materials. After 20 to 60 minutes of feeding, when finished products begin to be discharged from the kiln head, gradually adjust the reduction parameters to the normal production control level. The feeding rate of silo 3 can be adjusted by adjusting the frequency of the screw feeder on silo 3.

[0013] As a further aspect of the present invention, the feeding amount of the silo is adjusted by adjusting the frequency of the screw feeder on the silo.

[0014] As a further aspect of the present invention: when the material is first fed, and after 20 to 60 minutes of feeding, when finished products begin to be discharged from the kiln head, the reduction parameters are gradually adjusted to the normal production control level, including adjusting the temperature of reduction point 1 to 600℃ to 700℃, raising the temperature of point 2 to 700℃ to 800℃, raising the temperatures of points 3 and 4 to 850℃ to 950℃, and raising the temperature of point 5 to 550℃ to 650℃ after 20 to 60 minutes of feeding. Adjust the reducing gas flow rate to 190–240 m³ / h; The feed rate of the silo is controlled at 450-500 kg / h.

[0015] Compared with the prior art, the beneficial effects of the present invention are: the present invention effectively solves the problem of easy ring formation in the initial stage of feeding of the reduction kiln, ensuring smooth production, and at the same time reducing the labor intensity of cleaning the ring-formed material in the reduction kiln. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the reduction kiln used for vanadium trioxide production in an embodiment of the present invention; Figure 2 This is a flowchart of the main processes for the production of trioxide; Figure 3 This is a flowchart illustrating the feeding operation method of the reduction kiln for vanadium trioxide production in an embodiment of the present invention.

[0017] In the diagram: 1-reduction cylinder, 2-furnace chamber, 3-material hopper, 4-sealed water tank, 5-material container, 6-cooling water tank, 7-exhaust pipe, 8-exhaust gas pipe. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Example 1 Please see Figure 1 In Embodiment 1 of the present invention, a reduction kiln for the production of vanadium trioxide is provided, comprising: The reduction cylinder 1 is filled with reducing gas. The furnace 2 is fitted outside the reduction cylinder 1, and the furnace 2 is equipped with multiple burners for heating the reduction cylinder 1; the burners are connected to compressed air and combustion gas, and the combustion gas can be coal gas.

[0020] The hopper 3 is used to add raw materials to the reduction cylinder 1; the hopper 3 is equipped with a screw feeder for feeding materials to the reduction cylinder 1.

[0021] Material tank 5 is used to collect the finished product produced by reduction cylinder 1.

[0022] Inside the furnace chamber 2, reduction points 1, 2, 3, 4 and 5 are arranged sequentially and at intervals along the material conveying direction of the reduction cylinder 1 to detect and control the reduction temperature.

[0023] The hopper 3 and the tank 5 are respectively located at both ends of the reduction cylinder 1. The reduction cylinder 1 is arranged at an angle, which facilitates the flow of raw materials inside the reduction cylinder 1.

[0024] Specifically, the material is fed to the reduction cylinder 1 through the opening on the hopper 3, and the feeding speed is controlled by the screw feeder. After feeding is completed, reducing gas is introduced into the reduction cylinder 1. At the same time, the reduction cylinder 1 rotates, the reducing gas reacts with the raw materials, and then the finished product is produced.

[0025] like Figure 1 As shown, in a preferred embodiment of the present invention, the reduction kiln of the present invention further includes a cooling water tank 6, which is used to cool the packing position on the reduction cylinder 1 to ensure sealing.

[0026] like Figure 1 As shown, in a preferred embodiment of the present invention, the reduction cylinder 1 is rotatably mounted on the support. To drive the reduction cylinder 1 to rotate, a drive motor is also included, which is connected to the reduction cylinder 1.

[0027] like Figure 1 As shown, in a preferred embodiment of the present invention, packing is provided at the connection between the reduction cylinder 1 and the silo 3 and the connection between the material tank 5 for sealing the interface of the reduction cylinder 1, and the cooling water tank 6 is used to seal the packing at the connection to ensure the sealing effect of the interface.

[0028] like Figure 1 As shown, in a preferred embodiment of the present invention, the present invention further includes an exhaust gas treatment device for purifying the exhaust gas discharged from the reduction cylinder 1.

[0029] The exhaust gas treatment device includes a sealed water tank 4 and an exhaust gas pipe 8. The inlet of the sealed water tank 4 is connected to the interior of the reduction cylinder 1, and the outlet of the sealed water tank 4 is connected to the inlet of the exhaust gas pipe 8. The sealed water tank 4 contains a purification medium, which can be water. The exhaust gas from the reduction cylinder 1 after the raw material reduction treatment is discharged through the sealed water tank 4 and the exhaust gas pipe 8. The sealed water tank 4 is used to remove particulate matter from the exhaust gas before it is discharged through the exhaust gas pipe 8.

[0030] like Figure 1 As shown, in a preferred embodiment of the present invention, the furnace 2 is also provided with a flue gas exhaust pipe 7, which is used to exhaust the flue gas from the combustion inside the furnace 2.

[0031] like Figure 1 As shown, in a preferred embodiment of the present invention, the outlet of the reduction cylinder 1 is also provided with a screw conveyor device, which is existing technology and will not be described in detail here.

[0032] The production of industrial vanadium trioxide involves feeding ammonium polyvanadate (APV) material into a drying hot air furnace for drying. After drying, the material is fed into a reduction kiln, which is an externally combusted, closed rotary kiln. The APV material is continuously and stably fed into the kiln and undergoes a reduction reaction with the reducing medium within a reasonable temperature range, ultimately producing V2O3 product.

[0033] Example 2 like Figure 2 and 3 As shown, this embodiment of the invention also provides a method for feeding materials into a reduction kiln for vanadium trioxide production, comprising the following steps S10 to S40: S10. Adjust the air-coal ratio of the burners inside furnace 2 to raise the temperature of reduction point 1 to 500℃~750℃, the temperature of reduction point 2 to 600℃~800℃, the temperature of reduction points 3 and 4 to 700℃~900℃, and the temperature of reduction point 5 to 450℃~650℃. S20. Adjust the flow rate of the reducing gas input to the reducing cylinder 1 to 200-400 m³ / h; S30. When the reduction temperature and reduction gas flow rate inside furnace 2 reach the requirements, control the feed rate of silo 3 to be 600-900 kg / h. S40. Start feeding materials. After 20-60 minutes of feeding, when finished products start to be discharged from the kiln head, gradually adjust the reduction parameters to the normal production control level.

[0034] In a preferred embodiment of the present invention, the feeding amount of the silo 3 is adjusted by adjusting the frequency of the screw feeder on the silo 3.

[0035] As a preferred embodiment of the present invention, when feeding begins, and after 20 to 60 minutes of feeding, when finished products begin to be discharged from the kiln head, the reduction parameters are gradually adjusted to the normal production control level. This includes adjusting the temperature at point 1 to 600°C to 700°C, raising the temperature at point 2 to 700°C to 800°C, raising the temperatures at points 3 and 4 to 850°C to 950°C, and raising the temperature at point 5 to 550°C to 650°C after 20 to 60 minutes of feeding. Adjust the reducing gas flow rate to 190–240 m³ / h; The feed rate of silo 3 is controlled at 450-500 kg / h.

[0036] This invention effectively solves the problem of ring formation in the initial stage of feeding in reduction kilns, ensuring smooth production and reducing the labor intensity of cleaning ring-formed materials in reduction kilns.

[0037] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "top," "bottom," "inner," "outer," "upper," "lower," "front," "rear," "left," "right," "vertical," and "horizontal," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention 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 the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more. Features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature.

[0038] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0039] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for feeding materials into a reduction kiln used in the production of vanadium trioxide, characterized in that, The reduction kiln includes, The reduction cylinder is filled with reducing gas. The furnace chamber fitted outside the reduction cylinder; The furnace chamber is equipped with multiple burners for heating the reduction cylinder; each burner is connected to compressed air and combustion gas; reduction points 1, 2, 3, 4 and 5 are arranged sequentially and at intervals along the material conveying direction of the reduction cylinder inside the furnace chamber for detecting and controlling the reduction temperature. A hopper for adding raw materials to the reduction cylinder, the hopper being equipped with a screw feeder for supplying materials to the reduction cylinder; and a tank for collecting the finished product produced by the reduction cylinder; The feeding operation method includes: Adjust the air-coal ratio of the burners inside the furnace to raise the temperature of reduction point 1 to 500℃~750℃, the temperature of reduction point 2 to 600℃~800℃, the temperature of reduction points 3 and 4 to 700℃~900℃, and the temperature of reduction point 5 to 450℃~650℃. Adjust the flow rate of reducing gas input into the reduction cylinder to 200-400 m³ / h of reducing gas; Once the reduction temperature and reducing gas flow rate inside the furnace reach the required levels, control the feed rate of the silo to 600–900 kg / h. Start feeding. After 20-60 minutes, when finished products begin to be discharged from the kiln head, adjust the temperature at reduction point 1 to 600℃-700℃, the temperature at point 2 to 700℃-800℃, the temperatures at points 3 and 4 to 850℃-950℃, and the temperature at point 5 to 550℃-650℃. Adjust the reduction gas flow rate to 190-240 m³ / h and control the feed rate of the silo to 450-500 kg / h.

2. The feeding operation method of a reduction kiln for vanadium trioxide production according to claim 1, characterized in that, The hopper and the tank are respectively located at both ends of the reduction cylinder.

3. The feeding operation method of a reduction kiln for vanadium trioxide production according to claim 1, characterized in that, The reduction cylinder is arranged at an angle.

4. The feeding operation method of a reduction kiln for vanadium trioxide production according to claim 1, characterized in that, It also includes a cooling water tank, which is used to cool the packing area on the reduction cylinder.

5. The feeding operation method of a reduction kiln for vanadium trioxide production according to claim 1, characterized in that, It also includes an exhaust gas treatment device for purifying the exhaust gas discharged from the reduction cylinder.

6. The feeding operation method of a reduction kiln for vanadium trioxide production according to claim 5, characterized in that, The exhaust gas treatment device includes a sealed water tank and an exhaust gas pipeline. The input end of the sealed water tank is connected to the inside of the reduction cylinder, and the output end of the sealed water tank is connected to the input end of the exhaust gas pipeline. The sealed water tank contains a purification medium.

7. The feeding operation method of a reduction kiln for vanadium trioxide production according to claim 1, characterized in that, The furnace is also equipped with a flue pipe.

8. The feeding operation method of a reduction kiln for vanadium trioxide production according to claim 1, characterized in that, The feed rate of the silo can be adjusted by changing the frequency of the screw feeder on the silo.

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