Ardealite slurry carbonization reaction device and carbonization reaction method
By incorporating a feed turntable, annular gas distribution pipe, and agitation and scraping design, the problems of uneven gas distribution, low mass transfer efficiency, and difficulty in slurry discharge in the phosphogypsum carbonization reactor have been solved, achieving a highly efficient, stable, and simple carbonization reaction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-11
- Publication Date
- 2026-04-07
AI Technical Summary
Existing phosphogypsum carbonization reactors suffer from problems such as uneven gas distribution, low mass transfer efficiency, easy scaling on the inner wall, and difficulty in discharging high-solids slurry. Furthermore, their reliance on complex control systems increases costs and failure rates.
The reactor design features a feed turntable and annular gas distribution pipe, combined with an agitator and a scraper anchor frame to achieve uniform contact and forced circulation of the slurry and CO2. It is equipped with a large-diameter inclined discharge port and a manual control system to prevent scaling and clogging.
It increases the gas-liquid contact area and mixing efficiency, ensuring uniform suspension and rapid discharge, reducing equipment costs and maintenance difficulty, and improving the reliability and ease of operation of the device.
Smart Images
Figure CN121797236A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of industrial solid waste resource utilization and carbon capture technology, specifically a phosphogypsum slurry carbonization reaction device and carbonization reaction method. Background Technology
[0002] Phosphogypsum is a large-scale industrial solid waste generated during the wet-process phosphoric acid production. Its storage not only occupies a significant amount of land but also poses risks of environmental pollution and leakage. Meanwhile, CO2 emissions from industrial flue gas are a major contributor to the greenhouse effect. Utilizing alkaline phosphogypsum slurry to chemically fix acidic CO2 is an ideal technical approach for simultaneously disposing of solid waste and capturing carbon dioxide.
[0003] Existing phosphogypsum carbonization reactors mostly employ traditional stirred tank or bubble column structures, which generally suffer from the following technical problems: First, CO2 gas is typically introduced through a simple bottom or side opening, resulting in uneven gas distribution, low contact efficiency with the high-solids-content slurry, poor mass transfer, and consequently, slow reaction rates and incomplete carbonization. Second, during the reaction, the slurry easily forms scale on the inner wall of the reactor and on the stirring components, which not only worsens heat transfer and reduces effective volume but also seriously affects the long-term continuous operation of the unit. Third, the high-solids-content, high-viscosity carbonized slurry is difficult to discharge and easily clogs the outlet. Furthermore, to improve control precision, some existing technologies have introduced complex online sensors and automatic control systems, but this significantly increases equipment investment, maintenance costs, and system failure rates, making it impractical in complex industrial environments. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide a carbonization reaction device and carbonization reaction method for phosphogypsum slurry, which can solve the problems of uneven gas distribution, low mass transfer efficiency, easy scaling on the inner wall, difficulty in discharging high solid content slurry, and reliance on complex control systems in the prior art.
[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a carbonization reaction device for phosphogypsum slurry, comprising a reaction vessel body, wherein a main shaft is provided inside the reaction vessel body, a stirring paddle and a wall-scraping anchor frame are installed on the main shaft, and a scraper that fits against the inner wall of the reaction vessel body is installed on the wall-scraping anchor frame. The reactor body is equipped with a feed turntable near the top. The feed turntable is fixed on the main shaft by a bracket and rotates together with the main shaft. An annular air distribution pipe is provided above the feed turntable, and an exhaust hole is provided on the annular air distribution pipe.
[0006] In a preferred embodiment, a jacket is provided on the outer wall of the reactor body, and the jacket is provided with a jacket medium inlet and a jacket medium outlet.
[0007] In a preferred embodiment, a hand hole is provided on the side wall of the reactor body, and a pressure-resistant sight glass is provided on the hand hole.
[0008] In a preferred embodiment, the reactor body has a feed inlet at the top and a discharge outlet at the bottom; The feed inlet output end is located above the feed turntable, and the discharge outlet is inclinedly set at the bottom of the reactor body.
[0009] In a preferred embodiment, a CO2 inlet pipe is connected to the annular gas distribution pipe, and the CO2 inlet pipe is equipped with a rotor flow meter and a manual regulating valve.
[0010] In a preferred embodiment, the main shaft is driven by a motor located at the top of the reactor body; The reactor body is also equipped with a gearbox for controlling the motor speed.
[0011] In a preferred embodiment, a pressure gauge and a temperature controller are provided on the top of the reactor body. The pressure gauge and temperature controller are used to monitor the pressure and temperature parameters inside the reactor body.
[0012] The carbonization reaction method based on the above-mentioned phosphogypsum slurry carbonization reaction device includes the following steps: S1. Pump a phosphogypsum slurry with a solid content of 15%-40% into the main body of the reactor through the feed inlet; S2. By operating the manual regulating valve and according to the reading of the rotor flow meter, manually preset the CO2 intake flow rate, and preset the stirring speed of the main shaft by adjusting the gearbox; S3. Turn on the CO2 gas source and drive the motor to start the carbonization reaction, and control the reaction temperature inside the reactor body by manually adjusting the flow rate of the medium introduced into the jacket. S4. During the reaction process, maintain the preset air intake flow rate, stirring speed and reaction temperature at a constant level; S5. After the reaction reaches the predetermined time, stop the CO2 supply and stop stirring. The carbonized slurry is completely discharged from the large-diameter inclined discharge port under the rotational propulsion of the scraper anchor frame.
[0013] In a preferred embodiment, in step S1, the feed turntable centrifugally sprays the phosphogypsum slurry falling onto it while rotating, and the annular air distribution pipe is located above or to the side of the spraying path of the feed turntable, so that the sprayed slurry and the CO2 gas released from the exhaust hole can fully contact and mix in the space.
[0014] In a preferred embodiment, in step S4, the stirring paddle and the wall-scraping anchor frame rotate to form a forced circulating flow field covering the entire reactor body, rapidly dispersing the gas-liquid-solid three-phase material initially mixed in the feed turntable area to the entire reaction area and maintaining the suspension state of the solid particles.
[0015] The carbonization reaction apparatus and carbonization reaction method for phosphogypsum slurry provided by the present invention have the following beneficial effects by adopting the above-described structure and method: (1) The pumped slurry is centrifugally sprayed by a feed turntable set on the main shaft and rotating with it and an annular gas distribution pipe located above the turntable, so that it can fully contact and premix with the CO2 microbubbles evenly distributed from top to bottom in the space during the falling process. The design breaks through the limitations of traditional bottom or side gas distribution, and greatly improves the gas-liquid contact area and mixing efficiency from the initial stage of the reaction, laying a good foundation for subsequent deep carbonization. (2) The mechanical stirring mechanism that integrates the stirring paddle and the wall-scraping anchor frame provides strong axial and radial circulating power during operation, forming forced convection covering the entire area inside the vessel, ensuring uniform suspension of solid particles and eliminating flow dead zones. Meanwhile, the scraper rotating close to the inner wall can continuously scrape off newly formed soft scale, effectively preventing heat transfer deterioration and effective volume reduction caused by scale thickening, ensuring that the device can operate continuously for a long time, stably and efficiently. (3) The bottom of the reactor adopts a large-diameter inclined discharge port. Combined with the rotating and pushing effect of the scraping mechanism in the discharge stage, it can overcome the flow resistance of high-viscosity materials and achieve thorough and rapid discharge of carbonized slurry, avoiding the risk of blockage. The CO2 flow rate, stirring speed and reaction temperature of the entire system are manually preset and adjusted by the rotor flow meter, manual regulating valve, local gearbox and jacket valve, eliminating the need for complex online sensors and automatic control systems, significantly reducing equipment cost, maintenance difficulty and failure rate, and improving the ease of operation and reliability in industrial field environment. Attached Figure Description
[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 This is a schematic diagram of the overall structure of the device of the present invention.
[0017] Figure 2 This is a cross-sectional structural diagram of the present invention.
[0018] Figure 3 This is a schematic diagram of the vertical section structure of the present invention.
[0019] Figure 4 This is a schematic diagram of the annular air distribution pipe structure of the present invention.
[0020] Figure 5 This is a schematic diagram of the internal structure of the reactor body of the present invention.
[0021] In the diagram: 1. Reactor body; 2. Jacket; 3. Annular gas distribution pipe; 4. Support; 5. Main shaft; 6. Stirring paddle; 7. Scraper anchor frame; 8. Scraper; 9. Pressure-resistant sight glass; 10. Manhole; 11. Feed inlet; 12. Discharge outlet; 13. CO2 inlet pipe; 14. Rotor flow meter; 15. Manual regulating valve; 16. Gearbox; 17. Motor; 19. Feed turntable; 20. Jacket medium inlet; 21. Jacket medium outlet; 22. Pressure gauge; 23. Temperature controller; 24. Exhaust port. Detailed Implementation
[0022] Example 1: The reactor body 1 is a vertical pressure vessel, preferably made of 316L stainless steel. A mechanical seal is located at the center of its top for the insertion and sealing of the main shaft 5. The top also features a feed inlet 11, an interface for connecting to the gas distribution system, and interfaces for installing a pressure gauge 22 and a temperature controller 23. A handhole 10 is provided on the side wall, with a pressure sight glass 9 installed for easy observation of the internal condition and maintenance. A jacket 2 is provided outside the reactor body 1, with a jacket medium inlet 20 and a jacket medium outlet 21 forming a temperature control system for introducing steam (heating) or cooling water (cooling). A discharge port 12 is connected to the bottom of the reactor body 1. This discharge port 12 is designed with a large diameter and its central axis forms an angle with the vertical direction, creating an inclined structure that facilitates slurry collection.
[0023] The drive system includes a motor 17 mounted on the top of the reactor and a gearbox 16 connected between the output shaft of the motor 17 and the main shaft 5. The gearbox 16 is preferably a multi-stage gearbox or a continuously variable transmission, used to preset and adjust the speed of the main shaft 5 and achieve a fixed speed output.
[0024] The stirring and scraping system is the core moving component of the device, specifically including: The lower end of the main shaft 5 extends into the reactor vessel. An agitator 6 is installed at the lower part of the main shaft 5; in this embodiment, a double-layered inclined-blade turbine agitator is preferred to provide strong radial and axial flow. Above or at the same height as the agitator 6, a feed turntable 19 is fixedly installed via a bracket 4. This turntable rotates synchronously with the main shaft 5. At the lowest part of the main shaft 5, a wall-scraping anchor frame 7 is connected. The shape of this frame 7 closely matches the contour of the reactor vessel's inner wall. At the corresponding position where the frame 7 contacts the reactor wall, a scraper 8 is installed. The scraper 8 is preferably made of a material with good wear resistance and a certain degree of elasticity, such as polytetrafluoroethylene (PTFE) or ultra-high molecular weight polyethylene (UPE), and is bolted to the frame 7 to ensure that its working surface effectively adheres to and scrapes the inner wall.
[0025] The gas distribution system mainly consists of an annular gas distribution pipe 3, which is fixed to the top of the reactor interior by a bracket, located above the feed turntable 19. Several downward-facing or slightly inclined exhaust holes 24 are evenly distributed along the circumference of the annular gas distribution pipe 3. The small diameter of the exhaust holes 24 helps to break the CO2 gas into microbubbles. The annular gas distribution pipe 3 is connected to an external CO2 gas source via a pipeline. A manual regulating valve 15 and a rotor flow meter 14 are sequentially installed on the connecting pipeline, forming a manual control unit for manually setting and displaying the CO2 inlet flow rate.
[0026] The probes of pressure gauge 22 and temperature controller 23 (which can be a thermometer or a thermocouple) extend into the top space of the reactor to monitor pressure and temperature changes during the reaction process, providing operators with a reference for manual adjustment.
[0027] Example 2: The working principle of this device is based on the synergistic effect of mechanical structures, and can be divided into the feeding premixing stage, the reaction enhancement stage, and the discharge stage.
[0028] The specific feed premixing stage is as follows: The motor 17 is started, and a low speed suitable for feeding and mixing is set through the gearbox 16, driving the main shaft 5 to rotate. A phosphogypsum slurry with a solid content of 15%-40% is pumped into the reactor through the feed inlet 11. The slurry falls onto the high-speed rotating feed turntable 19, where it is rapidly atomized into droplets or thin layers under centrifugal force, dispersing in all directions. Simultaneously, CO2 gas, after its flow rate is set by the manual regulating valve 15, enters the annular gas distribution pipe 3 and is uniformly released from the exhaust port 24 below it in the form of numerous microbubbles. The atomized slurry and the rising / suspended CO2 microbubbles collide, intersect, and contact violently in the space above the feed turntable 19, achieving preliminary and efficient mixing and dispersion of the gas, liquid, and solid phases. This process greatly increases the initial contact area, overcoming the shortcomings of simple gas bubbling, which easily aggregates and distributes unevenly.
[0029] The reaction enhancement phase is as follows: After feeding is complete, the stirring speed can be adjusted to a higher preset reaction speed. At this point, the device enters the deep carbonization reaction period. The powerful fluid shear force and pumping action generated by the high-speed rotation of the agitator 6 create a strong forced circulation flow field covering the entire reactor. This flow field has the following key functions: (1) Three-dimensional mass transfer: The material that has been partially mixed during the feeding stage is rapidly transported and dispersed to every corner of the reactor, so that CO2 bubbles and slurry can continuously and fully contact and react in three-dimensional space.
[0030] (2) Particle suspension: The strong axial flow can effectively overcome the gravitational settling tendency of solid particles (such as unreacted phosphogypsum, generated calcium carbonate, etc.) in high solids content slurry, keeping them basically in a uniform suspension state, ensuring that all solid phase surfaces can participate in the reaction, and avoiding bottom sediment.
[0031] (3) Update the surface: Turbulence continuously renews the gas-liquid and solid-liquid interfaces, reducing diffusion resistance and continuously enhancing the mass transfer process.
[0032] At the same time, the wall-scraping anchor frame 7 drives the scraper 8 to rotate closely against the vessel wall, and its core function is: (1) Continuous scale prevention: In real time, any soft or nascent scale that may form on the inner wall due to water evaporation, crystallization, or adhesion during the reaction process is scraped off to keep the inner wall clean, ensuring that the heat of the jacket 2 can be efficiently transferred to the reactants and maintaining the effective volume of the reactor.
[0033] (2) Elimination of dead zones: The slurry layer with a low flow rate close to the wall is forcibly pushed into the main circulation flow, which completely eliminates the flow dead zones that may exist in traditional stirring, so that the entire reaction system can achieve high uniformity.
[0034] During this stage, the reaction temperature is controlled within a suitable range (e.g., 50-80℃) by manually adjusting the flow rate of the medium (steam or cooling water) in jacket 2. The entire process relies on a preset fixed rotation speed and a fixed CO2 flow rate. The operator only needs to observe through sight glass 9 and make empirical fine adjustments based on the readings of pressure gauge 22 and temperature controller 23. The system is simple and reliable.
[0035] The material feeding stage is detailed as follows: Once the reaction reaches the predetermined time or conversion rate, the CO2 supply is stopped and the motor 17 is turned off. During discharge, the stirring can be briefly restarted (or inertia can be utilized), at which point the low-speed rotating scraper anchor frame 7 plays a crucial role. The scraper 8, like a scraper and pusher, scrapes away the viscous slurry adhering to the bottom and side walls and pushes it towards the inclined discharge port 12. Because the discharge port 12 has a large diameter, low resistance, and an inclined angle that facilitates the convergence and flow of the slurry under gravity, even high-solids, high-viscosity carbonized slurry can be quickly, thoroughly, and smoothly discharged without residue under the physical propulsion of the scraper mechanism and the action of gravity, preparing for the next batch of production.
[0036] This invention achieves innovative initial dispersion of gas and liquid through a rotating feed turntable combined with a top annular air distribution system. Powerful stirring combined with synchronous wall scraping creates a highly efficient forced circulation and anti-scaling mechanism. A large-diameter inclined discharge port, coupled with wall scraping assistance, solves the problem of discharging high-solids-content slurries. Furthermore, a fully manual preset unit achieves extreme system simplification and high reliability. Each mechanical component has a clearly defined function and works synergistically to achieve efficient, stable, and continuous carbonization of phosphogypsum slurry without relying on complex electrical controls.
Claims
1. A carbonization reaction apparatus for phosphogypsum slurry, characterized in that: The reactor body (1) includes a main shaft (5) inside the reactor body (1), a stirring paddle (6) and a wall scraping anchor frame (7) are installed on the main shaft (5), and a scraper (8) that fits against the inner wall of the reactor body (1) is installed on the wall scraping anchor frame (7). The reactor body (1) is provided with a feed turntable (19) near the top. The feed turntable (19) is fixed to the main shaft (5) by a bracket (4) and rotates together with the main shaft (5). An annular air distribution pipe (3) is provided above the feed turntable (19), and an exhaust hole (24) is provided on the annular air distribution pipe (3).
2. The phosphogypsum slurry carbonization reaction apparatus according to claim 1, characterized in that: The outer wall of the reactor body (1) is provided with a jacket (2), and the jacket (2) is provided with a jacket medium inlet (20) and a jacket medium outlet (21).
3. The phosphogypsum slurry carbonization reaction apparatus according to claim 1, characterized in that: The reactor body (1) has a hand hole (10) on its side wall, and a pressure-resistant sight glass (9) is provided on the hand hole (10).
4. The phosphogypsum slurry carbonization reaction apparatus according to claim 1, characterized in that: The reactor body (1) is provided with a feed inlet (11) at the top and a discharge outlet (12) at the bottom. The feed inlet (11) is located above the feed turntable (19), and the discharge port (12) is inclined at the bottom of the reactor body (1).
5. The phosphogypsum slurry carbonization reaction apparatus according to claim 1, characterized in that: The annular air distribution pipe (3) is connected to a CO2 inlet pipe (13), and the CO2 inlet pipe (13) is equipped with a rotor flow meter (14) and a manual regulating valve (15).
6. The phosphogypsum slurry carbonization reaction apparatus according to claim 1, characterized in that: The main shaft (5) is driven by a motor (17) located on the top of the reactor body (1); The reactor body (1) is also equipped with a gearbox (16) for controlling the speed of the motor (17).
7. The phosphogypsum slurry carbonization reaction apparatus according to claim 1, characterized in that: The reactor body (1) is equipped with a pressure gauge (22) and a temperature controller (23) on the top. The pressure gauge (22) and the temperature controller (23) are used to monitor the pressure and temperature parameters inside the reactor body (1).
8. A carbonization reaction method based on the phosphogypsum slurry carbonization reaction apparatus according to any one of claims 1-7, characterized in that... Includes the following steps: S1. Pump a phosphogypsum slurry with a solid content of 15%-40% into the reactor body (1) through the feed inlet (11); S2. By operating the manual regulating valve (15) and according to the reading of the rotor flow meter (14), the CO2 intake flow rate is manually preset, and the stirring speed of the main shaft (5) is preset by adjusting the gearbox (16). S3. Start the carbonization reaction by turning on the CO2 gas source and drive motor (17), and control the reaction temperature inside the reactor body (1) by manually adjusting the flow rate of the medium introduced into the jacket (2); S4. During the reaction process, maintain the preset air intake flow rate, stirring speed and reaction temperature at a constant level; S5. After the reaction reaches the predetermined time, stop the CO2 supply and stop stirring. The carbonized slurry is completely discharged from the large-diameter inclined discharge port (12) under the rotational propulsion of the scraper anchor frame (7).
9. The carbonization reaction method of the phosphogypsum slurry carbonization reaction device according to claim 8, characterized in that: In step S1, the feed turntable (19) centrifugally sprays the phosphogypsum slurry falling on it when it rotates. The annular air distribution pipe (3) is located above or to the side of the spraying path of the feed turntable (19), so that the sprayed slurry and the CO2 gas released from the exhaust hole (24) can fully contact and mix in the space.
10. The carbonization reaction method of the phosphogypsum slurry carbonization reaction apparatus according to claim 8, characterized in that: In step S4, the stirring paddle (6) and the wall-scraping anchor frame (7) form a forced circulating flow field covering the entire reactor body (1) by rotating, which rapidly disperses the gas-liquid-solid three-phase material initially mixed in the feed turntable (19) area to the entire reaction area and maintains the suspension state of solid particles.