Production system for refining carbazide

Abstract

The utility model relates to the technical field of carbazide production, in particular to a production system for refining carbazide, which comprises a first dissolving kettle, a discharge port of the first dissolving kettle is communicated with a first adsorption device, a discharge port of the first adsorption device is communicated with a first crystallization kettle, and a crystal outlet of the first crystallization kettle is communicated with a second dissolving kettle. A discharge port of the second dissolving kettle is communicated with a second adsorption device, a discharge port of the second adsorption device is communicated with a second crystallization kettle, a crystal outlet of the second crystallization kettle is communicated with a washing tank, a discharge port of the washing tank is communicated with a drying device, and a discharge port of the drying device is communicated with a product storage tank. The production system is reasonable in design, and the purity of carbazide is greatly improved.

Description

Technical Field

[0001] This utility model relates to the field of carbazide production technology, and in particular to a production system for the purification of carbazide. Background Technology

[0002] Carbazine is a widely used chemical in the chemical industry, encompassing various forms such as propanecarbazine hydrochloride and diphenylcarbazine. Currently, industrial production technologies for carbazine are quite mature, primarily including the urea process, the dimethyl carbonate process, and the phosgene process. The urea process utilizes readily available and relatively inexpensive raw materials, urea and hydrazine hydrate, and offers relatively mild and controllable reaction conditions; however, the product purity is relatively low, requiring further purification. Therefore, to address these issues, it is necessary to develop a production system for the purification of carbazine. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a production system for the purification of carbazine, which greatly improves the purity of carbazine, in view of the shortcomings of the existing technology.

[0004] To solve the above-mentioned technical problems, the technical solution of this utility model is as follows:

[0005] A production system for refining carbazine includes a first dissolving vessel, the outlet of which is connected to a first adsorption device, the outlet of which is connected to a first crystallization vessel, the crystal outlet of which is connected to a second dissolving vessel, the outlet of which is connected to a second adsorption device, the outlet of which is connected to a second crystallization vessel, the crystal outlet of which is connected to a washing tank, the outlet of which is connected to a drying device, and the outlet of which is connected to a product storage tank.

[0006] As an improved technical solution, both the first dissolving vessel and the second dissolving vessel include a vessel body. The top and bottom of the vessel body are respectively provided with a feed inlet and a discharge outlet. The vessel body is provided with a jacket on the outside and a stirring shaft is provided inside the vessel body. One end of the stirring shaft is connected to a motor. A cylindrical stirring frame is provided on the stirring shaft. Multiple stirring components are provided on the stirring frame. An auxiliary stirring component is provided between two adjacent stirring components.

[0007] As an improved technical solution, the stirring component is a hollow triangular stirring plate, and the auxiliary stirring component is a Y-shaped stirring rod.

[0008] As an improved technical solution, the first crystallization vessel and the second crystallization vessel include a vessel body, with a feed inlet and a crystal outlet at the top and bottom of the vessel body, respectively, and a liquid outlet on one side of the lower part of the vessel body. A filter screen is provided inside the vessel body at a position corresponding to the liquid outlet. A jacket is provided outside the vessel body, and a rotating shaft is provided inside the vessel body. One end of the rotating shaft is connected to a motor, and multiple stirring rods are provided on the rotating shaft.

[0009] As an improved technical solution, the first adsorption device includes a body, with an inlet and an outlet at the top and bottom of the body, respectively. The body has a first adsorption layer, a second adsorption layer and a third adsorption layer inside, wherein the first adsorption layer and the second adsorption layer are both activated carbon adsorption layers, and the third adsorption layer is a strong acid cation exchange resin layer.

[0010] As an improved technical solution, the second adsorption device includes a body, with an inlet and an outlet respectively at the top and bottom of the body. The body has a first adsorption layer and a second adsorption layer inside, the first adsorption layer being a weak cation exchange resin layer and the second adsorption layer being a strong base anion exchange resin layer.

[0011] After adopting the above technical solution, the beneficial effects of this utility model are:

[0012] The production system for refining carbazide includes a first dissolving vessel, the outlet of which is connected to a first adsorption device, the outlet of which is connected to a first crystallization vessel, the crystal outlet of which is connected to a second dissolving vessel, the outlet of which is connected to a second adsorption device, the outlet of which is connected to a second crystallization vessel, the crystal outlet of which is connected to a washing tank, the outlet of which is connected to a drying device, and the outlet of which is connected to a product storage tank. In actual production, the prepared crude carbazine is fed into the first dissolving vessel, where water is added and the mixture is heated and stirred to dissolve. The resulting solution is then pumped to the first adsorption unit to remove impurities such as pigments and metal ions. After impurity removal, the solution enters the first crystallization vessel, where it is cooled and crystallized. Uncrystallized impurities are removed by a filtration pump while remaining in the liquid. The precipitated carbazine crystals are then conveyed to the second dissolving vessel via a conveyor belt. Water is added and the mixture is heated and stirred to dissolve. The dissolved solution is then pumped to the second adsorption unit, where further removal of cations and anions is achieved. The solution is then pumped to the second crystallization vessel, where it is cooled and crystallized. Uncrystallized impurities are removed by a filtration pump while remaining in the liquid. The precipitated crystals are conveyed to a washing tank via a conveyor belt. After washing, the crystals are conveyed to the drying unit via a conveyor belt and finally stored in a product storage tank. The above-mentioned production system is reasonably designed. Through the treatment of the first adsorption device and the second adsorption device, pigments, metal cations and anions can be removed. Through the crystallization treatment of the first crystallization kettle and the second crystallization kettle, impurities can be further removed, realizing the separation of impurities and carbazine, and greatly improving the purity of carbazine.

[0013] Both the first and second dissolving kettles include a kettle body, with an inlet at the top and an outlet at the bottom. The kettle body is fitted with a jacket, and an agitator shaft is located inside. One end of the agitator shaft is connected to a motor, and a cylindrical agitator frame is mounted on the shaft. Multiple agitator components are mounted on the agitator frame, and auxiliary agitator components are positioned between adjacent agitator components. Crude carbazide and crystals precipitated from the first crystallization kettle enter the first and second dissolving kettles, respectively. After water is added, heating is achieved using a heat transfer medium in the jacket. Once the motor starts, it drives the agitator shaft, cylindrical agitator frame, multiple agitator components, and auxiliary agitator components to work together to mix the carbazide material and water, promoting rapid dissolution of the carbazide in the water for subsequent processing.

[0014] The stirring component is a hollow triangular stirring plate, and the auxiliary stirring component is a Y-shaped stirring rod. The synergistic effect of the triangular stirring plate and the Y-shaped stirring rod increases the stirring range, promotes full contact between carbazine and water, improves the dissolution efficiency of carbazine, and facilitates subsequent processing.

[0015] The first and second crystallization vessels each consist of a vessel body with a feed inlet at the top and a crystal outlet at the bottom, and a liquid outlet on one side of the lower part of the vessel body. A filter screen is installed inside the vessel body corresponding to the liquid outlet. The vessel body has an external jacket and an internal rotating shaft with a motor connected to one end. Multiple stirring rods are mounted on the rotating shaft. The carbazide-containing liquid enters the vessel body and is cooled to the crystallization temperature by a refrigerant in the jacket. After the motor starts, it drives the rotating shaft and multiple stirring rods to stir the liquid, promoting uniform cooling and significantly improving crystallization efficiency. Uncrystallized impurities in the mother liquor are extracted through the filter screen by a suction pump. The first and second crystallization vessels with the above structure are rationally designed, achieving effective crystallization of carbazide while also separating carbazide from impurities.

[0016] The first adsorption device comprises a main body with an inlet at the top and an outlet at the bottom. Inside the main body are a first adsorption layer, a second adsorption layer, and a third adsorption layer. The first and second adsorption layers are both activated carbon adsorption layers, and the third adsorption layer is a strongly acidic cation exchange resin layer. The dissolved crude carbazide solution enters the main body and passes through the first, second, and third adsorption layers. The first and second adsorption layers effectively remove pigment impurities, while the third adsorption layer effectively removes metal cation impurities. This first adsorption device is rationally designed and can effectively remove pigments and metal cation impurities from carbazide, thus improving the purity of carbazide.

[0017] The second adsorption device comprises a main body with an inlet at the top and an outlet at the bottom. Inside the main body are a first adsorption layer and a second adsorption layer. The first adsorption layer is a weakly acidic cation exchange resin layer, and the second adsorption layer is a strongly basic anion exchange resin layer. The carbazide solution dissolved in the second dissolving vessel enters the main body. The first adsorption layer removes some metal cations, and the second adsorption layer effectively removes anions. This second adsorption device is rationally designed, achieving the separation of carbazide and impurities, and significantly improving the purity of the carbazide product. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the production system for refining carbazide according to the present invention;

[0019] Among them, 1-first dissolving vessel, 10-stirring component, 11-auxiliary stirring component, 2-first adsorption device, 20-first adsorption layer, 21-second adsorption layer, 22-third adsorption layer, 3-first crystallization vessel, 4-second dissolving vessel, 5-second adsorption device, 50-first adsorption layer, 51-second adsorption layer, 6-second crystallization vessel, 7-washing tank, 8-drying device, 9-product storage tank. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0021] A production system for the refining of carbazine, such as Figure 1 As shown, the system includes a first dissolving vessel 1, the outlet of which is connected to a first adsorption device 2, the outlet of which is connected to a first crystallization vessel 3, the crystal outlet of which is connected to a second dissolving vessel 4, the outlet of which is connected to a second adsorption device 5, the outlet of which is connected to a second crystallization vessel 6, the crystal outlet of which is connected to a washing tank 7 (including a tank body, the top of which is open, the bottom of which has an outlet, the lower side of which has a washing liquid outlet, and a filter screen on the inner wall of which is located at the position corresponding to the washing liquid outlet; a rotating shaft is horizontally installed inside the tank body, one end of which is connected to a motor, and a stirring rod is installed on the rotating shaft), the outlet of which is connected to a drying device 8 (oven), and the outlet of which is connected to a product storage tank 9. The first adsorption device 2 includes a main body with an inlet and an outlet at the top and bottom, respectively. Inside the main body are a first adsorption layer 20, a second adsorption layer 21, and a third adsorption layer 22. The first and second adsorption layers 20 and 21 are both activated carbon adsorption layers, and the third adsorption layer 22 is a strongly acidic cation exchange resin layer (macroporous strongly acidic cation exchange resin - D001). The second adsorption device 5 also includes a main body with an inlet and an outlet at the top and bottom, respectively. Inside the main body are a first adsorption layer 50 and a second adsorption layer 51. The first adsorption layer is a weakly acidic cation exchange resin layer (D113 resin), and the second adsorption layer is a strongly basic anion exchange resin layer (strongly basic styrene-based anion exchange resin).

[0022] In actual production, the prepared crude carbazine is fed into the first dissolving vessel, water is added, and the mixture is heated and stirred to dissolve. The resulting solution is then pumped into the first adsorption device, passing through the first adsorption layer (activated carbon layer), the second adsorption layer (activated carbon layer), and the third adsorption layer (strong acid cation exchange resin layer). The first and second adsorption layers effectively remove pigment impurities, while the third adsorption layer effectively removes metal cation impurities. The purified solution then enters the first crystallization vessel, where it is cooled and crystallized. Uncrystallized impurities are removed by a filtration pump while remaining in the liquid. The precipitated carbazine crystals are then conveyed to the second adsorption vessel via a conveyor belt. Inside the dissolving vessel, water is added, heated, and stirred to dissolve the metal cations. The dissolved solution is then pumped into the second adsorption unit. Passing through the first adsorption layer (a weakly acidic cation exchange resin layer), some metal cations are removed. Passing through the second adsorption layer (a strongly basic anion exchange resin layer), anions are effectively removed. The treated solution is then pumped into the second crystallization vessel. After cooling and crystallization, uncrystallized impurities are removed by a filtration pump. The precipitated crystals are conveyed into a washing tank. After washing, the crystals are conveyed to the drying unit and finally stored in a product storage tank. This production system is rationally designed. The first and second adsorption units remove pigments, metal cations, and anions. The crystallization processes in the first and second crystallization vessels further remove impurities, achieving separation of impurities and carbazine, significantly improving the purity of carbazine.

[0023] Both the first dissolving vessel 1 and the second dissolving vessel 4 include a vessel body, with an inlet and an outlet at the top and bottom of the vessel body, respectively. The vessel body is fitted with a jacket, and a stirring shaft is installed inside the vessel body. One end of the stirring shaft is connected to a motor, and a cylindrical stirring frame is mounted on the stirring shaft. Multiple stirring components 10 are mounted on the stirring frame, and an auxiliary stirring component 11 is positioned between adjacent stirring components. Crude carbazide and crystals precipitated from the first crystallization vessel enter the first and second dissolving vessels, respectively. After water is added, heating is performed using a heat transfer medium in the jacket. Once the motor starts, it drives the stirring shaft, the cylindrical stirring frame, the multiple stirring components, and the auxiliary stirring components to work together to mix the carbazide material and water, promoting rapid dissolution of the carbazide in the water for subsequent processing.

[0024] Because the stirring component 10 is a hollow triangular stirring plate, and the auxiliary stirring component 11 is a Y-shaped stirring rod, the synergistic effect of the triangular stirring plate and the Y-shaped stirring rod increases the stirring range, promotes full contact between carbazine and water, improves the dissolution efficiency of carbazine, and facilitates subsequent processing.

[0025] The first crystallization vessel 3 and the second crystallization vessel 6 each include a vessel body. The top and bottom of the vessel body are respectively equipped with a feed inlet and a crystal outlet. A liquid outlet is located on one side of the lower part of the vessel body. A filter screen is installed inside the vessel body at a position corresponding to the liquid outlet. The vessel body is equipped with a jacket, and a rotating shaft is located inside the vessel body. One end of the rotating shaft is connected to a motor, and multiple stirring rods are installed on the rotating shaft. The feed solution containing carbazide enters the interior of the vessel body and is cooled to the crystallization temperature by the refrigerant in the jacket. After the motor starts, it drives the rotating shaft and multiple stirring rods to stir the feed solution, promoting uniform cooling and greatly improving crystallization efficiency. Uncrystallized impurities in the mother liquor are extracted through the filter screen by a suction pump.

[0026] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A production system for refining a carbazate, characterized by comprising: a carbazate production device; a carbazate refining device; and a carbazate storage device. The system includes a first dissolving vessel, the outlet of which is connected to a first adsorption device, the outlet of which is connected to a first crystallization vessel, the crystal outlet of which is connected to a second dissolving vessel, the outlet of which is connected to a second adsorption device, the outlet of which is connected to a second crystallization vessel, the crystal outlet of which is connected to a washing tank, the outlet of which is connected to a drying device, and the outlet of which is connected to a product storage tank.

2. The production system for refining a carbazate according to claim 1, wherein Both the first and second dissolving vessels include a vessel body. The top and bottom of the vessel body are respectively provided with a feed inlet and a discharge outlet. The vessel body is provided with a jacket on the outside and a stirring shaft is provided inside the vessel body. One end of the stirring shaft is connected to a motor. A cylindrical stirring frame is provided on the stirring shaft. Multiple stirring components are provided on the stirring frame. An auxiliary stirring component is provided between two adjacent stirring components.

3. The production system for refining carbazide according to claim 2, wherein The stirring component is a triangular stirring plate with a hollow structure, and the auxiliary stirring component is a Y-shaped stirring rod.

4. The production system for refining carbazide according to claim 1, wherein The first crystallization vessel and the second crystallization vessel each include a vessel body. The top and bottom of the vessel body are respectively provided with a feed inlet and a crystal outlet. A liquid outlet is provided on one side of the lower part of the vessel body. A filter screen is provided inside the vessel body at a position corresponding to the liquid outlet. A jacket is provided on the outside of the vessel body. A rotating shaft is provided inside the vessel body. One end of the rotating shaft is connected to a motor. Multiple stirring rods are provided on the rotating shaft.

5. The production system for refining carbazide according to claim 1, wherein The first adsorption device includes a body, with an inlet and an outlet at the top and bottom of the body, respectively. The body has a first adsorption layer, a second adsorption layer and a third adsorption layer inside. The first and second adsorption layers are both activated carbon adsorption layers, and the third adsorption layer is a strong acid cation exchange resin layer.

6. The production system for refining a carbazate according to claim 1, wherein The second adsorption device includes a body, with an inlet and an outlet at the top and bottom of the body, respectively. The body has a first adsorption layer and a second adsorption layer inside, the first adsorption layer being a weak cation exchange resin layer and the second adsorption layer being a strong base anion exchange resin layer.

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