A wet-process phosphoric acid high-efficiency fluorine resource recovery device

Abstract

The utility model discloses a kind of high-efficiency fluorine resource recovery devices of wet-process phosphoric acid, belong to wet-process phosphoric acid technical field, including processing device, recovery device, processing device includes feed tank, reaction device, separating device, concentration device;Recovery device includes absorption tower, reaction tank;Fluorine-containing gas generated in reaction device, concentration device can be into absorption tower by pipeline, recycling by reaction tank.By the utility model, phosphor slurry or wet-process phosphoric acid raw material can be stored in feed tank, transported to reaction device by pipeline to carry out acidolysis or chemical reaction, then sent to separating device by screw conveyor to realize solid-liquid separation, finally sent to concentration device to further improve phosphoric acid concentration, ensure the continuity of phosphoric acid production process, and fluorine-containing gas is released in reaction and concentration two links.

Description

Technical Field

[0001] This utility model relates to a high-efficiency fluorine resource recovery device for wet-process phosphoric acid, belonging to the field of wet-process phosphoric acid technology. Background Technology

[0002] Wet-process phosphoric acid is produced by decomposing phosphate rock with sulfuric acid, nitric acid, or hydrochloric acid. The raw materials naturally contain a certain amount of fluoride. During the production process, some of the fluoride in the phosphate rock dissolves into the acid solution, resulting in high concentrations of fluoride ions in the wet-process phosphoric acid and subsequent process waste liquids. Direct discharge of these fluoride-containing waste liquids not only causes environmental pollution but may also pose potential risks to human health. Since fluorides have certain industrial applications, such as as raw materials or additives in metallurgy and chemical industries, the efficient recovery of fluoride ions from waste liquids has significant economic and environmental implications. Therefore, it is necessary to control and recover fluoride resources during the production process.

[0003] Traditional wet-process phosphoric acid treatment for fluorine removal typically employs direct precipitation or adsorption ion exchange. However, these methods have several drawbacks: direct precipitation suffers from poorly controlled reaction conditions and low recovery rates; adsorption ion exchange is complex, costly, and unsuitable for large-scale continuous production. Therefore, it is necessary to design a highly efficient fluorine resource recovery device for wet-process phosphoric acid. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a wet-process phosphoric acid high-efficiency fluorine resource recovery device, which solves the problem.

[0005] The technical problem to be solved by this utility model is achieved by the following technical solution: a wet-process phosphoric acid high-efficiency fluorine resource recovery device, comprising...

[0006] Processing equipment, recycling equipment,

[0007] The recycling device is connected to the processing device.

[0008] The processing device includes a feeding tank, a reaction device, a separation device, and a concentration device. The feeding tank is connected to the reaction device via a pipeline, the reaction device is connected to the separation device via a screw conveyor, and the separation device is connected to the concentration device via a pipeline.

[0009] The recovery device includes an absorption tower and a reaction tank. The absorption tower is connected to the reaction device and the concentration device through pipelines. The reaction tank is located at the bottom of the absorption tower.

[0010] The fluorine-containing gas generated in the reaction device and the concentration device can enter the absorption tower through a pipeline and be recovered through the reaction tank.

[0011] Preferably, the pipes are connected by a flange seal.

[0012] Preferably, the reaction device is a closed stirred tank, and the inner side of the closed stirred tank is made of corrosion-resistant steel plate.

[0013] Preferably, the absorption tower is a multi-stage gas-liquid contact device.

[0014] Preferably, the pipelines between the absorption tower and the reaction device and the concentration device are all connected by flange seals, and check valves are also installed in the pipelines.

[0015] Preferably, the reaction tank is equipped with a stirring and heating device.

[0016] The beneficial effects of this utility model are:

[0017] (1) Through this utility model, the processing device includes a feeding tank, a reaction device, a separation device, and a concentration device. It can store phosphate rock slurry or wet-process phosphoric acid raw material in the feeding tank, transport it through pipeline to the reaction device for acid hydrolysis or chemical reaction, and then send it to the separation device through a screw conveyor to achieve solid-liquid separation. Finally, it is sent to the concentration device to further increase the phosphoric acid concentration, ensuring the continuity of the phosphoric acid production process, and releasing fluorine-containing gas in the reaction and concentration stages.

[0018] (2) This utility model provides a recovery device at the bottom of the processing unit. The recovery device includes an absorption tower and a reaction tank. The fluorine-containing gas discharged from the reaction unit and the concentration unit flows into the absorption tower through a pipeline. After multi-stage gas-liquid contact, the fluorine-containing components are absorbed to the liquid phase at the bottom or side wall of the tower. The absorbent or the fluorine-containing product generated after absorption flows into the reaction tank for stirring, heating, further conversion, or crystallization recovery. This enables centralized recovery of fluorine resources.

[0019] (3) Through this utility model, flange sealing and check valve design are adopted at all key connection pipelines, and the screw conveyor achieves full sealing in the solid-liquid conveying section, reducing gas and liquid leakage; ensuring corrosion-resistant sealing between various equipment, reducing environmental pollution risks and improving recycling efficiency. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the device of this utility model.

[0021] In the diagram: 1-feeding tank, 2-reaction device, 3-separation device, 4-concentration device, 5-absorption tower, 6-reaction tank. Detailed Implementation

[0022] In order to make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0023] Example 1

[0024] like Figure 1 As shown, a wet-process phosphoric acid high-efficiency fluorine resource recovery device includes a processing unit and a recovery unit. The recovery unit and the processing unit are connected by a pipeline.

[0025] In this embodiment, the processing device includes a feeding tank 1, a reaction device 2, a separation device 3, and a concentration device 4. The feeding tank 1 and the reaction device 2 are connected by a pipeline, the reaction device 2 and the separation device 3 are connected by a bolt conveyor, and the separation device 3 and the concentration device 4 are connected by a pipeline.

[0026] The feeding tank 1 is a vertical cylindrical storage tank with a sealable top. The tank body is equipped with a feed inlet, an exhaust outlet, and an inspection port. A corrosion-resistant steel plate is installed on the inner side of the feeding tank 1 to resist corrosion from phosphate rock slurry or acidic materials.

[0027] Storage tank 1 is used to store and uniformly transport wet-process phosphoric acid raw materials or phosphate rock slurry. It is connected to the reaction device 2 via a pipeline, with flange seals at both ends of the pipeline connection. In this embodiment, a metering pump is installed inside the pipeline, and a valve is installed at one end to control the amount of raw material transferred and prevent backflow or overpressure.

[0028] In this embodiment, the reaction device 2 is a closed stirred tank. A stirrer is installed at the top of the stirred tank, and the shaft of the stirrer extends into the stirred tank. The inside of the reaction device 2 is treated with corrosion resistance, specifically, a corrosion-resistant steel plate is installed inside the closed stirred tank. A coil is installed inside the tank for heating or cooling.

[0029] The reaction device 2 can carry out acid hydrolysis of the raw materials sent from the feed tank 1. During the acid hydrolysis process, a certain amount of fluorine-containing gas will be released. Stirring and heating / cooling ensure that the reaction proceeds uniformly. After the reaction is completed, the solid-liquid mixture is discharged from the bottom or side of the vessel and transported to the separation device 3.

[0030] In this embodiment, the top of the reaction device 2 is also provided with an exhaust port. The generated fluorine-containing gas is connected to the absorption tower 5 through a pipeline to prevent gas leakage. The connected pipeline is connected by a flange and a check valve is installed in the pipeline to prevent gas leakage.

[0031] The side wall near the bottom of the reaction device 2 is equipped with a screw conveyor connected to the separation device 3. The screw conveyor can transport semi-fluid or slurry materials from the reaction device 2 to the separation device 3.

[0032] A feed inlet is provided on the top of the side wall of the reaction device 2. The feed inlet is connected to the feed tank 1 by a pipe, and a flange seal is provided at the pipe connection.

[0033] In this embodiment, the separation device 3 is a filter, which can separate the solid-liquid mixture from the reaction device 2 to obtain phosphogypsum or other solid by-products. The filtrate obtained by the separation device 3 contains phosphoric acid and some impurities, and is then transported to the concentration device 4 for further concentration.

[0034] One end of the separation device 3 is connected to a screw conveyor, and the material enters the separation device 3 for filtration. The bottom of the separation device 3 is equipped with a pipe, which is connected to the concentration device 4 by means of a continuous sealing connection. An outlet is provided on the other side of the separation device 3, where solid by-products can be discharged. The solid by-products are transported to a waste disposal site or further utilized.

[0035] In this embodiment, the concentration device 4 is a vacuum evaporator with a vertical cylindrical structure. It has a steam outlet at the top, a heating tube bundle inside, and a phosphoric acid solution collection area at the bottom. The concentration device 4 can evaporate and concentrate the phosphoric acid solution delivered by the separation device 3, increasing the phosphoric acid concentration. During the evaporation and concentration process, water in the solution is evaporated, and fluorine-containing gases may be released.

[0036] The concentrator 4 has a feed inlet on its side, which is connected to the separator 3 by a flange-sealed pipe. The concentrator 4 has an exhaust port at its top, through which the fluorine-containing gas generated during the concentration process is transferred to the absorption tower 5 via a pipe. The concentrator 4 has a concentrated phosphoric acid outlet at its bottom, which can collect and process the concentrated phosphoric acid.

[0037] Absorption tower 5 is a vertical cylindrical tower with a multi-stage gas-liquid contact device inside; a spray system is installed at the top and a gas inlet or gas distribution section is installed at the bottom; a sight glass, pressure gauge, thermometer and sampling port are installed on the outside of absorption tower 5 to facilitate operation monitoring.

[0038] Absorption tower 5 can be used to recover fluorine-containing gases. Fluorine-containing gases from reaction unit 2 and concentration unit 4 are passed into the tower and come into full contact with the absorbent to generate fluoride solutions or other recoverable products. Multi-stage gas-liquid contact can improve the absorption rate and enhance the recovery efficiency of fluorine resources.

[0039] The top of the absorption tower 5 is equipped with an air inlet, which is connected to the reaction device 2 and the concentration device 4 through pipes, sealed with flanges and equipped with check valves in the pipes; the bottom of the absorption tower 5 is equipped with a liquid outlet, which can introduce the fluorine-containing solution generated by the reaction into the reaction tank 6.

[0040] In this embodiment, the reaction tank 6 is a vertical cylindrical shape with a stirring and heating device, and has a flat bottom. It can be adjusted according to the absorption tower 5, and can be integrated with the absorption tower 5, or it can be set up separately next to the absorption tower and connected by a short pipe or flange.

[0041] The fluorine-containing liquid collected in absorption tower 5 enters reaction tank 6 for fluorine resource recovery under stirring and heating conditions. Stirring and heating ensure uniform solution temperature and concentration, preventing localized crystallization or precipitation. A discharge port is provided on the side of absorption tower 5 for conveying the generated fluoride solution / crystals to subsequent processing or storage equipment.

[0042] In this embodiment, the feed tank 1 is connected to the reaction device 2 via a flange-sealed pipe; the reaction device 2 is connected to the separation device 3 via a bolt conveyor to transfer the solid-liquid mixture; the separation device 3 is connected to the concentration device 4 via a flange-sealed pipe, which can send the filtered or settled phosphoric acid solution into the concentration device through the flange-sealed pipe connection; both the reaction device 2 and the concentration device 4 are connected to the absorption tower 5, and each is provided with two fluorine-containing gas pipes connected to the absorption tower, both of which are flange-sealed and equipped with check valves. The absorption tower 5 can efficiently absorb fluorine-containing gases, reduce fluorine pollution and recover fluorine resources; the bottom of the absorption tower 5 is connected to the reaction tank 6 via a pipe or an integrated opening, and the fluorides carried are entered into the reaction tank 6 for stirring, heating and subsequent conversion or storage.

[0043] This embodiment enables a closed-loop process flow of raw material transportation, reaction, separation, concentration, and fluorine-containing gas recovery. Fluorine-containing byproducts are concentrated in the absorption tower and reaction tank for recovery and conversion, greatly reducing fluorine pollution from external discharge and improving the utilization rate of fluorine resources. The pipelines are connected by flange seals, and check valves are installed at key locations to effectively prevent gas backflow or leakage, thereby improving production safety and environmental performance.

[0044] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments, and various changes and modifications can be made without departing from the spirit and scope of this utility model. All such changes and modifications fall within the scope of protection claimed by this utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A wet-process high-efficiency fluorine resource recovery device for phosphoric acid, comprising: Processing equipment, recycling equipment, The recycling device is connected to the processing device. Its features are: The processing device includes a feeding tank, a reaction device, a separation device, and a concentration device. The feeding tank is connected to the reaction device via a pipeline, the reaction device is connected to the separation device via a screw conveyor, and the separation device is connected to the concentration device via a pipeline. The recovery device includes an absorption tower and a reaction tank. The absorption tower is connected to the reaction device and the concentration device through pipelines. The reaction tank is located at the bottom of the absorption tower. The fluorine-containing gas generated in the reaction device and the concentration device can enter the absorption tower through a pipeline and be recovered through the reaction tank.

2. The wet-process high-efficiency fluorine resource recovery device for phosphoric acid according to claim 1, characterized in that: The pipes are connected by flanges for sealing.

3. The wet-process high-efficiency fluorine resource recovery device for phosphoric acid according to claim 1, characterized in that: The reaction device is a closed stirred tank, and the inner side of the closed stirred tank is made of corrosion-resistant steel plate.

4. The wet-process high-efficiency fluorine resource recovery device for phosphoric acid according to claim 1, characterized in that: The absorption tower is a multi-stage gas-liquid contact device.

5. The wet-process high-efficiency fluorine resource recovery device for phosphoric acid according to claim 1, characterized in that: The pipelines connecting the absorption tower to the reaction device and the concentration device are all connected by flange seals, and check valves are also installed in the pipelines.

6. The wet-process high-efficiency fluorine resource recovery device for phosphoric acid according to claim 1, characterized in that: The reaction tank is equipped with a stirring and heating device.

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