Oxidation kettle for producing sodium dichloroquinoline-8-quinoline carboxylate

Abstract

The utility model discloses an oxidation kettle for producing sodium dichloroquinoline-8-quinoline carboxylate, which belongs to the technical field of oxidation kettles and comprises an oxidation kettle, an interlayer is arranged on the outer wall of the oxidation kettle, and a temperature adjusting pipeline is arranged in the interlayer; the bottom of the oxidation kettle is provided with a discharge port, and the top is provided with an upper cover body; a material feeding opening, a plurality of liquid inlet pipes and a transmission box are arranged at the upper end of the upper cover body, a transmission device is arranged in the transmission box, and the lower end of the transmission device is fixedly connected with a stirring device; the stirring device comprises a stirring shaft, the stirring shaft is of a hollow structure, a pipeline is rotatably arranged in the hollow structure, and the upper end of the pipeline penetrates out of the stirring shaft and then extends to the outer side of the transmission box; a plurality of open grooves are formed in the side wall of the stirring shaft in the vertical direction at equal intervals, and a plurality of air outlet holes are formed in the pipeline at the open grooves. According to the oxidation kettle for producing sodium dichloroquinoline-8-quinoline carboxylate, disclosed by the utility model, the risk of flash explosion can be obviously reduced, and the safety of the whole production process is improved.

Description

Technical Field

[0001] This utility model relates to the field of oxidation reactor technology, and in particular to an oxidation reactor for the production of sodium dichloroquinoline-8-quinolinecarboxylate. Background Technology

[0002] Sodium dichloroquinoline-8-quinolinecarboxylate is a quinoline acid hormone-type herbicide that is low in toxicity, highly effective, and highly selective. It is a highly effective selective herbicide for controlling barnyard grass in rice fields. It is mainly used to control barnyard grass and has a long applicable period, being effective from the 1 to 7 leaf stage. It is safe for rice and highly effective in killing barnyard grass. Currently, the industrialized production process of dichloroquinoline acid by nitric acid oxidation involves first preparing 7-chloro-8-methylquinoline from 3-chloro-2-methylaniline and glycerol, then reacting 7-chloro-8-methylquinoline with chlorine to generate 3,7-dichloro-8-methylquinoline chloride, and finally oxidizing the 3,7-dichloro-8-methylquinoline chloride in concentrated sulfuric acid with concentrated nitric acid to obtain sodium dichloroquinoline carboxylate. In the oxidation reaction stage: water and sulfuric acid are added to the oxidation reactor according to the metered amount, stirring is started, and the tail gas absorption system is activated. Then, the chloride is added to the oxidation reactor and the temperature is raised. When the temperature reaches 110℃, nitric acid is added dropwise. After 12 hours of dropwise addition, the temperature is raised to 115-125℃ and maintained at this temperature for 13 hours. After the holding period, the temperature is lowered while the gas is expelled. When the temperature drops to 50℃, the lower layer of material is placed into the precipitation reactor. In the above process, excessively high oxygen concentrations (>30%) or localized accumulation in the oxidation reactor can easily trigger flash explosions. Oxidation reactions are typically exothermic; excessively high oxygen concentrations in the reactor accelerate the reaction rate, generating more heat. When this heat cannot dissipate in time, the temperature inside the reactor rises sharply, further accelerating the reaction and creating a vicious cycle that may ultimately lead to a runaway reaction and flash explosion. Based on this, this invention proposes an oxidation reactor for the production of sodium dichloroquinoline-8-quinolinecarboxylate. By employing a stepped air intake distribution method, oxygen enters the reactor in layers and at multiple angles, avoiding the localized oxygen-rich zones caused by traditional single-hole air intake. Utility Model Content

[0003] The purpose of this invention is to provide an oxidation reactor for the production of sodium dichloroquinoline-8-quinolinecarboxylate, thereby solving the aforementioned problems.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0005] This utility model discloses an oxidation reactor for the production of sodium dichloroquinoline-8-quinolinecarboxylate, comprising an oxidation reactor with an outer wall having a jacket, and a temperature regulating pipeline installed within the jacket; a discharge port is provided at the bottom of the oxidation reactor, and an upper cover is provided at the top; the upper end of the upper cover is provided with a material inlet, several liquid inlet pipes, and a transmission box, and a transmission device is provided inside the transmission box; a reduction motor is fixedly connected to the upper end of the transmission device, and a stirring device is fixedly connected to the lower end of the transmission device;

[0006] The transmission device includes a bevel gear one fixedly connected to the reduction motor, the bevel gear one meshing with a bevel gear two, the bevel gear two meshing with a bevel gear three, and the bevel gear three fixedly connected to the stirring device;

[0007] The stirring device includes a stirring shaft, which is a hollow structure. A pipe is rotatably installed inside the hollow structure. The upper end of the pipe extends out of the stirring shaft and extends to the outside of the transmission box. Several slots are equally spaced vertically on the side wall of the stirring shaft. Several air outlets are provided on the pipe located at the slots. The air outlets are connected to an external air source through a vent pipe, which is located inside the pipe. A stirring mechanism is provided on the outer wall of the stirring shaft.

[0008] Furthermore, the inlet and outlet of the temperature regulating pipeline are respectively connected to a high-temperature water pipe or a cooling water pipe.

[0009] Furthermore, several mounting brackets are circumferentially distributed on the outer wall of the oxidation vessel. These mounting brackets are used to connect support components / suspension components to support the oxidation vessel.

[0010] Furthermore, a rotary seal is provided between the inner wall of the stirring shaft and the outer wall of the pipeline at the groove.

[0011] Furthermore, the length of the vent hole is less than the wall thickness of the rotary seal.

[0012] Furthermore, a sealing element is provided between the air outlet and the wall of the vent pipe.

[0013] Furthermore, the stirring mechanism includes a number of fasteners sleeved on the outer wall of the stirring shaft, and the end of the fastener away from the stirring shaft is provided with stirring blades via a connecting rod; the number of stirring blades are distributed in a spiral shape.

[0014] Furthermore, the bottom of the stirring shaft is provided with bottom stirring blades that are compatible with the bottom of the oxidation reactor.

[0015] Compared with the prior art, the beneficial technical effects of this utility model are as follows:

[0016] This novel oxidation reactor for the production of sodium dichloroquinoline-8-quinolinecarboxylate utilizes equidistantly spaced slots to deliver oxygen in a stepped manner through the vents. This allows oxygen to enter at different heights or positions, promoting mixing and reducing localized accumulation. This helps maintain uniform oxygen concentration throughout the reactor, preventing certain areas from exceeding safe thresholds and thus reducing the risk of flash explosions. Furthermore, this design enhances the mixing of gaseous and liquid or solid reactants, improving reaction efficiency and reducing temperature rises caused by excessively vigorous localized reactions, thereby lowering the risk of runaway reactions. In summary, this novel oxidation reactor for the production of sodium dichloroquinoline-8-quinolinecarboxylate significantly reduces the risk of flash explosions and improves the safety of the entire production process. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings.

[0018] Figure 1 This is a front view of the oxidation reactor used in the production of sodium dichloroquinoline-8-quinolinecarboxylate according to this utility model;

[0019] Figure 2 This is a structural diagram of the transmission device inside the transmission box;

[0020] Figure 3 Here is a structural diagram of the stirring device;

[0021] Figure 4 This is a schematic diagram of the installation structure of the stirring shaft and pipeline;

[0022] Explanation of reference numerals in the attached drawings: 1. Oxidation kettle; 2. Jacket; 3. Temperature control pipeline; 4. Discharge port; 5. Upper cover; 6. Material feeding port; 7. Liquid inlet pipe; 8. Mounting frame; 9. Gear motor; 10. Transmission box; 11. Pipeline; 12. Bevel gear one; 13. Bevel gear two; 14. Bevel gear three; 15. Stirring shaft; 1501. Groove; 16. Fastener; 17. Connecting rod; 18. Stirring blade; 19. Bottom stirring blade; 20. Vent pipe; 21. Vent hole. Detailed Implementation

[0023] like Figures 1-4As shown, an oxidation reactor for the production of sodium dichloroquinoline-8-quinolinecarboxylate includes an oxidation reactor 1, which is an enamel-lined oxidation reactor with a volume of 10,000 L. The outer wall of the oxidation reactor 1 has a jacket 2, within which a temperature regulating pipe 3 is installed. The inlet and outlet of the temperature regulating pipe 3 are connected to a high-temperature water pipe or a cooling water pipe, respectively. By inputting hot or cold water, the oxidation reactor 1 is heated and cooled to meet the temperature requirements during operation. A discharge port 4 is installed at the bottom of the oxidation reactor 1, and a top cover 5 is installed at the top. The upper end of the top cover 5 is equipped with a material inlet 6, several liquid inlet pipes 7, and a transmission box 10. Several mounting brackets 8 are circumferentially distributed on the outer wall of the oxidation reactor 1. These mounting brackets 8 are used to connect support components / suspension components to support the oxidation reactor 1.

[0024] A transmission device is installed inside the transmission box 10. A reduction motor 9 is fixedly connected to the upper end of the transmission device, and a stirring device is fixedly connected to the lower end of the transmission device. The transmission device includes a bevel gear 12 fixedly connected to the reduction motor 9. The bevel gear 12 meshes with a bevel gear 13, and the bevel gear 13 meshes with a bevel gear 14. The bevel gear 14 is fixedly connected to the stirring device. The bevel gears 12 and 14 are bevel gears of the same structure, and in this embodiment, they are symmetrically arranged vertically. The bevel gear 13 meshes with both the bevel gear 12 and 14, thereby transmitting the transmission power from the bevel gear 12 to the bevel gear 14, which then drives the stirring device to perform the stirring operation.

[0025] The stirring device includes a stirring shaft 15, which is a hollow structure. A pipe 11 is rotatably mounted within the hollow structure. The upper end of the pipe 11 extends from the stirring shaft 15 to the outside of the transmission box 10. Specifically, the upper part of the pipe 11 is bent. After exiting the top of the stirring shaft 15, it bends 90° within the space formed by bevel gear 12, bevel gear 13, and bevel gear 14, and then extends to the outside of the transmission box 10 in a direction away from bevel gear 14, connecting to an oxygen supply source. Several slots 1501 are equidistantly spaced vertically on the side wall of the stirring shaft 15. The openings of the slots can be aligned or staggered, depending on the actual requirements. Several air outlets 21 are installed on the pipe 11 located at the slot 1501. These air outlets 21 are connected to an external air source via vent pipes 20. Each vent pipe 20 is equipped with a solenoid valve to control its opening and closing, thereby regulating the amount and rate of oxygen intake to meet precise control requirements. The vent pipes 20 are installed inside the pipe 11. Depending on the different air outlets 21 connected to the vent pipes 20, an appropriate length of vent pipe 20 is selected to achieve a tiered, stepped, and layered oxygen supply.

[0026] A stirring mechanism is installed on the outer wall of the stirring shaft 15. The stirring mechanism includes several fasteners 16 sleeved on the outer wall of the stirring shaft 15. At the end of each fastener 16 away from the stirring shaft 15, stirring blades 18 are mounted via a connecting rod 17. The stirring blades 18 are arranged in a spiral pattern, generating axial and radial combined flow during rotation, forming spiraling upward or downward vortices, causing the material to circulate and convect within the vessel. This flow pattern effectively breaks up liquid stratification (especially for high-viscosity materials or gas-liquid mixtures), preventing the accumulation of reactants, oxygen, or heat in localized areas, and reducing safety risks caused by uneven concentrations (such as flash explosions due to excessively high oxygen concentrations).

[0027] The bottom of the stirring shaft 15 is equipped with bottom stirring blades 19 that are compatible with the bottom of the oxidation vessel 1, which reduces the stirring blind zone and is especially suitable for materials containing solid particles or easily precipitated materials, preventing local concentration abnormalities caused by solid deposition.

[0028] A rotary seal is installed between the inner wall of the stirring shaft 15 and the outer wall of the pipe 11 at the slot 1501 to prevent fluid leakage between the stirring shaft 15 and the pipe 11.

[0029] The length of the vent 21 is less than the wall thickness of the rotary seal, ensuring that the rotating shaft 15 rotates stably and does not block the oxygen input into the reactor. That is, when the rotating shaft 15 rotates to the side of the slot 1501 away from the vent 21, the oxygen comes out from the vent 21 and is discharged into one side of the slot 1501 through the cavity formed between the inner wall of the stirring shaft 15 and the outer wall of the pipe 11, and finally enters the reactor to participate in the reaction. Since the stirring shaft 15 rotates continuously, there will be no regional accumulation of oxygen.

[0030] A seal is installed between the vent 21 and the wall of the vent pipe 20 to prevent liquid from entering the pipe 11.

[0031] The operation process of this utility model is as follows:

[0032] First, add water and sulfuric acid to oxidation reactor 1 according to the metered amount. Then, seal oxidation reactor 1 and, depending on the liquid level inside the reactor, open the vent valves 20 at different heights to introduce oxygen. Allowing oxygen to enter at different heights or positions promotes mixing and reduces local accumulation, which helps maintain the uniformity of oxygen concentration throughout the reactor and prevents oxygen concentration in certain areas from exceeding the safety threshold, thereby reducing the risk of flash explosion. Next, start the stirring device to ensure uniform mixing of materials and enhance mass transfer (gas dispersion) and heat transfer. Finally, introduce heat transfer oil, steam, or cooling water through the temperature control pipeline to control the temperature within the optimal reaction range and set the reaction time to achieve efficient conversion from raw materials to the target product.

[0033] The embodiments described above are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Various modifications and improvements made to the technical solutions of the present utility model by those skilled in the art without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. An oxidation reactor for the production of sodium dichloroquinoline-8-quinolinecarboxylate, characterized in that: The device includes an oxidation reactor (1), the outer wall of which is provided with a jacket (2), and a temperature regulating pipe (3) is provided inside the jacket (2); the bottom of the oxidation reactor (1) is provided with a discharge port (4), and the top is provided with an upper cover (5); the upper end of the upper cover (5) is provided with a material feeding port (6), several liquid inlet pipes (7) and a transmission box (10), and the transmission box (10) is provided with a transmission device, the upper end of which is fixedly connected to a reduction motor (9), and the lower end of which is fixedly connected to a stirring device; The transmission device includes a bevel gear one (12) fixedly connected to the reduction motor (9), the bevel gear one (12) meshing with a bevel gear two (13), the bevel gear two (13) meshing with a bevel gear three (14), and the bevel gear three (14) fixedly connected to the stirring device; The stirring device includes a stirring shaft (15), which is a hollow structure. A pipe (11) is rotatably arranged inside the hollow structure. The upper end of the pipe (11) extends out of the stirring shaft (15) and extends to the outside of the transmission box (10). Several slots (1501) are equidistantly arranged vertically on the side wall of the stirring shaft (15). Several air outlets (21) are arranged on the pipe (11) located at the slots (1501). The air outlets (21) are connected to an external air source through a vent pipe (20). The vent pipe (20) is arranged inside the pipe (11). A stirring mechanism is arranged on the outer wall of the stirring shaft (15).

2. The oxidation reactor for producing sodium dichloroquinoline-8-quinolinecarboxylate according to claim 1, characterized in that: The inlet and outlet of the temperature regulating pipeline (3) are respectively connected to a high-temperature water pipe or a cooling water pipe.

3. The oxidation reactor for producing sodium dichloroquinoline-8-quinolinecarboxylate according to claim 1, characterized in that: The oxidation vessel (1) has several mounting brackets (8) distributed circumferentially on its outer side wall. The mounting brackets (8) are used to connect the support assembly / suspension assembly to support the oxidation vessel (1).

4. The oxidation reactor for producing sodium dichloroquinoline-8-quinolinecarboxylate according to claim 1, characterized in that: A rotary seal is provided between the inner wall of the stirring shaft (15) at the slot (1501) and the outer wall of the pipeline (11).

5. The oxidation reactor for producing sodium dichloroquinoline-8-quinolinecarboxylate according to claim 4, characterized in that: The length of the vent (21) is less than the wall thickness of the rotary seal.

6. The oxidation reactor for producing sodium dichloroquinoline-8-quinolinecarboxylate according to claim 1, characterized in that: A sealing element is provided between the air outlet (21) and the wall of the vent pipe (20).

7. The oxidation reactor for producing sodium dichloroquinoline-8-quinolinecarboxylate according to claim 1, characterized in that: The stirring mechanism includes a number of fasteners (16) sleeved on the outer wall of the stirring shaft (15). The end of the fastener (16) away from the stirring shaft (15) is provided with stirring blades (18) through a connecting rod (17). The number of stirring blades (18) are arranged in a spiral shape.

8. The oxidation reactor for producing sodium dichloroquinoline-8-quinolinecarboxylate according to claim 7, characterized in that: The bottom of the stirring shaft (15) is provided with bottom stirring blades (19) that are compatible with the bottom of the oxidation vessel (1).

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