A super aeration floatation system and its implementation method

Abstract

The present invention discloses a super-aeration flotation system and its implementation method, belonging to the technical field of wet-process phosphoric acid production. The system comprises a reaction tank, an inclined guide plate arranged on the inner wall of the reaction tank, a dished trough arranged at the bottom of the reaction tank and arranged in a ring shape around its center, a central island formed by a protrusion of the inner ring portion of the dished trough at the bottom of the reaction tank, an aeration mechanism arranged on the central island and connected to the outside through a pipeline, a transmission mechanism installed above the reaction tank, a central transmission rod arranged along the axis of the reaction tank and connected to the output end of the transmission mechanism, a dynamic settler arranged at an upper position in the reaction tank and connected to the central transmission rod, and an overflow port matched with the dynamic settler. By integrating the inclined guide plate, the dished aeration structure and the dynamic settler in the reaction tank, the present invention significantly enhances the super-aeration uniformity, foam separation ability, phosphoric acid purification and liquid vortex intensity in the wet-process phosphoric acid production process, thereby improving reaction efficiency and product quality.

Description

Technical Field

[0001] The present invention relates to the technical field of wet-process phosphoric acid production, and in particular to a super aeration flotation system and an implementation method thereof. Background Art

[0002] The wet-process phosphoric acid process uses sulfuric acid, hydrochloric acid, and nitric acid, primarily sulfuric acid, to decompose phosphate rock, generating phosphoric acid and calcium sulfate. A series of acid hydrolysis, filtration, and purification processes separate the phosphoric acid from impurities. While this process is mature and boasts large-scale production, it presents challenges in handling phosphogypsum waste and improving product purity.

[0003] In the production of wet-process phosphoric acid, reaction efficiency and stability are crucial for ensuring product quality and improving production efficiency. With the continuous development of the wet-process phosphoric acid industry, the requirements for output and quality are increasing. Traditional production equipment and processes have gradually demonstrated their limitations and are unable to meet the needs of modern industry.

[0004] In the early days of wet-process phosphoric acid production, the aeration method for the reactor was relatively simple, typically employing conventional perforated pipe aeration or single-point aeration heads. This single aeration method resulted in uneven aeration distribution, severely impacting the mixing efficiency of the reaction solution. This prevented sufficient contact and reaction between the phosphate rock and sulfuric acid, reducing reaction efficiency and prolonging production time. It also resulted in unstable quality and high impurity content in the phosphoric acid and phosphogypsum products. Furthermore, insufficient aeration caused solid particles to easily settle and accumulate in the reaction solution, disrupting the normal reaction process and potentially causing blockages in pipes and equipment, increasing maintenance costs.

[0005] To address the issue of uneven aeration, some companies have attempted to increase the aeration volume to optimize the mixing of the reaction solutions, employing a hyperaeration process. However, while hyperaeration improves the mixing of the reaction solutions to a certain extent, it also introduces new problems. The influx of large amounts of gas causes a large amount of foam to form within the reaction tank. This foam accumulates at the top of the tank, occupying valuable reaction space and thus affecting the continuity and stability of the reaction. Furthermore, the presence of foam interferes with the gas-liquid separation process, potentially introducing bubbles into the phosphoric acid and phosphogypsum products, which reduces product quality.

[0006] Traditional methods, such as adding defoamers, have been used to address the problem of foam accumulation. While this approach has resolved the foaming issue to some extent, it also increases production costs and can negatively impact the reaction process, such as altering the chemical properties of the reaction system and affecting product quality. Furthermore, the use of defoamers can pose environmental concerns, as some defoamers are difficult to degrade, potentially causing environmental pollution.

[0007] Furthermore, the relatively simple liquid flow pattern within conventional reaction tanks fails to effectively promote uniform distribution of materials throughout the reaction space. Severe accumulation of materials in certain areas of the reaction tank prevents optimal reaction operation, hindering further improvements in production efficiency and product quality.

[0008] Due to numerous deficiencies in aeration, foam management, and liquid flow, conventional wet-process phosphoric acid production processes are no longer able to meet current demands for efficient, high-quality wet-process phosphoric acid production. Therefore, there is an urgent need for innovative technical solutions that can comprehensively address these challenges and optimize the wet-process phosphoric acid production process to meet the growing demand for phosphoric acid and phosphogypsum products in modern industry. Summary of the Invention

[0009] The present invention provides a super-aeration flotation system and its implementation method, aiming to solve a series of problems in the traditional wet-process phosphoric acid production process, such as uneven aeration, foam accumulation, and irrational liquid flow. By innovatively combining innovative structures such as inclined guide plates, dish-shaped aeration structures, and dynamic settlers, the wet-process phosphoric acid production process is fully optimized.

[0010] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0011] A super aeration flotation system comprises a reaction tank, an inclined guide plate arranged on the inner wall of the reaction tank, a dished tank arranged at the bottom of the reaction tank and arranged in a ring shape with its center, a central island formed by the inner ring portion of the dished tank protruding from the bottom of the reaction tank, an aeration mechanism arranged on the central island and connected to the outside through a pipeline, a transmission mechanism installed above the reaction tank through an external bracket, a central transmission rod arranged along the axis of the reaction tank and connected to the output end of the transmission mechanism, a dynamic settler arranged at an upper position in the reaction tank and connected to the central transmission rod, and an overflow port provided on the side wall of the reaction tank and matching the dynamic settler.

[0012] Specifically, the depth of the dished groove is 0.5 to 2.5 times, preferably 2 times, the installation height of the aeration mechanism; the width of the dished groove is 60% to 95% of the inner radius of the reaction tank.

[0013] Specifically, the aeration mechanism includes an aeration bracket installed at the bottom of the reaction tank, an aeration distribution ring installed on the aeration bracket and connected to an external air supply pipe, and a plurality of aeration nozzles evenly distributed on the aeration distribution ring, wherein the aeration nozzles are arranged downward at the bottom of the aeration distribution ring.

[0014] The present invention forms a dish-shaped aeration structure through the cooperation of the aeration mechanism and the dish-shaped trough, which promotes the reaction liquid after aeration to form a smooth circulation flow, thereby promoting material mixing at a deeper level and enhancing the uniformity of the reaction. The above-mentioned aeration mechanism is mainly aimed at the application conditions of direct air supply and aeration in the super-aeration flotation process of wet-process phosphoric acid. According to the actual application of the process, there is also an application condition of pre-aeration (or super-aeration) and then feeding. In this case, the structure can be adapted based on the above-mentioned aeration mechanism. The specific solution is: retain the structure of the above-mentioned aeration bracket and aeration distribution ring, connect the pipe connected to the aeration distribution ring to the external aerated material that has been pre-aerated / super-aerated, and replace the original aeration nozzle with a more direct aeration outlet structure. The aeration outlet structure is also configured downward at the bottom of the aeration distribution ring, thereby ensuring that the aerated material input by the dish-shaped aeration structure can form a smooth circulation flow.

[0015] Specifically, the inclined guide plate includes a plurality of downward-flipping guide plates arranged in a spiral shape along the upper position of the inner wall of the reaction tank and a plurality of upward-pressure guide plates arranged in a spiral shape along the lower position of the inner wall of the reaction tank. The spiral arrangement directions of the downward-flipping guide plates and the upward-pressure guide plates are opposite; the downward-flipping guide plates and the upward-pressure guide plates are intermittently point-connected to the inner wall of the reaction tank through a plurality of connecting rods, so that a gap is maintained between the inner edge of the guide plate and the inner wall of the reaction tank.

[0016] Specifically, the slope inclination angle between the head and tail ends of the downward-flip guide plate and the upward-pressure guide plate is 15 degrees to 60 degrees, preferably 45 degrees; the downward-flip guide plate is inclined 0 degrees to 30 degrees relative to the vertical direction of the inner wall in the stirring direction, preferably 15 degrees, and the upward-pressure guide plate is inclined 0 degrees to 30 degrees relative to the vertical direction of the inner wall in the stirring direction, preferably 15 degrees.

[0017] Specifically, a plurality of guide plate through holes are evenly opened on the downward-flipping guide plate and the upward-pressing guide plate, and the opening rate is 10% to 40%, preferably 35%.

[0018] The present invention can effectively guide the reaction liquid to form a three-dimensional circulation path through the specific layout design of the inclined guide plate. The downward-turning guide plate causes the upper liquid to turn downward, while the upward-pressing guide plate presses the lower liquid upward. The intersection of the two promotes the full mixing of the materials, avoids local accumulation, and thus improves the reaction efficiency and product quality.

[0019] Specifically, the dynamic settler includes a first settling mechanism and a second settling mechanism connected to a central transmission rod and arranged side by side, and a plurality of positioning connectors provided between the first settling mechanism and the second settling mechanism.

[0020] Specifically, the first sedimentation mechanism includes an upper splint and a lower splint arranged in parallel, a plurality of folding connectors densely arranged between the upper splint and the lower splint, a foam sedimentation channel formed between adjacent folding connectors, and sedimentation holes opened on the upper splint and the lower splint and connected to the foam sedimentation channel; the structure of the second sedimentation mechanism is the same as that of the first sedimentation mechanism, but the opening rate of the sedimentation holes of the second sedimentation mechanism is smaller than the opening rate of the sedimentation holes on the first sedimentation mechanism.

[0021] Specifically, the central transmission rod is provided with a rotating foam collector located above the second sedimentation mechanism and corresponding to the overflow port position. The rotating foam collector includes a plurality of spiral arms evenly distributed circumferentially around the central transmission rod, and a scraper head arranged at the end of the spiral arm, wherein the length of the spiral arm matches the inner radius of the reaction tank.

[0022] The present invention settles and separates the foam generated by the reaction by configuring a dynamic settler driven by a transmission mechanism at the upper position of the reaction tank, effectively solving the problem of foam accumulation in the upper part of the reaction tank, ensuring sufficient reaction space and stable reaction.

[0023] Based on the structure of the above-mentioned super aeration floatation system, the present invention also provides a method for implementing the super aeration floatation system, comprising the following steps:

[0024] S10. Preparation: Ensure that all components of the super aeration flotation system are intact and connected securely, that the raw materials are ready and the feeding equipment is functioning properly, and that the external air supply system is stable and the pipelines are airtight;

[0025] S20, feeding and initial aeration: the material enters the reaction tank through the feeding pipe, while the central island aeration mechanism supplies air, and the disc-shaped tank guides the aeration liquid circulation to start the reaction;

[0026] S30, Mixing Enhancement: Inclined guide plates guide the reaction liquid to form a three-dimensional circulation, combined with continuous aeration to promote uniform mixing and reaction of materials;

[0027] S40, super aeration and initial foam treatment: Increase the aeration volume to enter super aeration, and the generated foam is initially separated into gas and liquid by the first settling mechanism of the dynamic settler;

[0028] S50, secondary foam treatment and discharge: The initially treated foam enters the second settling mechanism for further separation and sedimentation, and is then scraped off by a rotating foam collector and discharged through an overflow port;

[0029] S60, discharging: After monitoring and judging the completion of the reaction, the product is discharged through the discharge pipe and the discharging parameters are controlled.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) By integrating the synergistic effects of the reaction tank, inclined guide plate, dished trough, aeration mechanism, and dynamic settler, the present invention significantly optimizes the uniformity of aeration distribution, promotes sufficient contact between phosphate rock and sulfuric acid, and thus significantly improves reaction efficiency and product quality. This comprehensive design not only improves the efficiency of the chemical reaction but also ensures a significant improvement in the quality of the final product by optimizing the reaction conditions.

[0032] (2) In the present invention, the annular layout of the dished grooves is combined with the corresponding depth and width design, and the spiral reverse arrangement and through-hole structure of the inclined guide plates together form a three-dimensional circulation flow path. This design effectively avoids the local accumulation of materials in the reactor and realizes the dynamic mixing enhancement of the reaction liquid. This not only improves the uniformity of the reaction, but also ensures sufficient contact between the reactants through continuous flow and mixing, thereby further improving the reaction rate.

[0033] (3) The aeration mechanism of the present invention is arranged based on the position of the central island. Through the coordination of the aeration distribution ring and the downward-facing aeration nozzle / aeration outlet, it ensures that the gas / gas-containing material can be evenly ejected and form a diffuse bubble flow. Combined with the configuration of the disc-shaped trough, the agitation and circulation power of the liquid are enhanced, thereby improving the aeration efficiency. In this way, the contact area between the gas and liquid during the mixing is maximized, making the oxygen transfer efficiency higher, thereby accelerating the progress of the chemical reaction.

[0034] (4) The dynamic settler of the present invention uses a two-stage settling mechanism with decreasing porosity in conjunction with a rotating foam collector to gradually settle and separate the gas and liquid components in the foam, which are promptly discharged through the overflow port. This effectively solves the problem of foam accumulation and ensures sufficient reaction space, thereby ensuring the smooth progress of the reaction process. Through this efficient foam treatment mechanism, the environment inside the reaction tank is effectively controlled, providing a guarantee for the smooth progress of the chemical reaction.

[0035] (5) The present invention implements a full-process design for feeding, aeration, mixing enhancement, foam treatment, and discharging, which closely connects the various stages of the wet-process phosphoric acid process, optimizes the continuity of system operation, and thus improves overall production efficiency. Through this comprehensive process control, every link in the production process is optimized, ensuring that every step from raw material input to final product output is efficient and smooth.

[0036] (6) The present invention effectively reduces the risk of equipment wear and scaling, enhances equipment stability, extends maintenance cycles and service life, reduces long-term operating costs, and provides higher economic benefits for industrial production through structural coordination designs such as uniform aeration, flow optimization by guide plates, and reduction of foam impact by dynamic settlers. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present invention.

[0038] Figure 2 This is a structural schematic diagram of the inner wall of a reaction tank equipped with inclined guide plates in an embodiment of the present invention.

[0039] Figure 3 This is another structural schematic diagram of the inner wall of a reaction tank equipped with inclined guide plates in an embodiment of the present invention.

[0040] Figure 4 This is another structural schematic diagram of the inner wall of a reaction tank equipped with inclined guide plates in an embodiment of the present invention.

[0041] Figure 5 Schematic diagram of the inclined arrangement structure of the inclined guide plate in the embodiment of the present invention, corresponding to Figure 2 BB cross section of area A in the middle.

[0042] Figure 6 The figure is a schematic diagram of the partial connection structure of a downward-flipping guide plate in an embodiment of the present invention.

[0043] Figure 7 It is a partial structural diagram of the aeration mechanism (direct supply) in an embodiment of the present invention.

[0044] Figure 8 Schematic diagram of the partial structure of the aeration mechanism (pre-aeration) in an embodiment of the present invention.

[0045] Figure 9 It is a structural schematic diagram of the dynamic settler part in an embodiment of the present invention.

[0046] Figure 10 Schematic diagram of the top view of the dynamic settler part in an embodiment of the present invention.

[0047] Figure 11 This is a structural diagram of the arrangement of two settling mechanisms in an embodiment of the present invention.

[0048] Figure 12 Schematic diagram of the structure of the first settling mechanism in an embodiment of the present invention.

[0049] The parts corresponding to the reference numerals are as follows:

[0050] 1-reaction tank, 2-inclined guide plate, 3-dish-shaped tank, 4-center island, 5-aeration mechanism, 6-transmission mechanism, 7-center transmission rod, 8-stirring blade, 9-overflow port, 10-dynamic settler, 11-first sedimentation mechanism, 12-second sedimentation mechanism, 13-positioning connector, 14-upper clamp, 15-lower clamp, 16-fold connector, 17-foam sedimentation channel, 18-rotating foam collector, 21-downward-flipping guide plate, 22-upward-pressure guide plate, 23-guide plate through hole, 24-connecting rod, 25-pipeline, 26-aeration bracket, 27-aeration distribution ring, 28-aeration nozzle, 29-aeration outlet structure, 31-swivel arm, 32-foam scraper. DETAILED DESCRIPTION

[0051] The present invention will be further described below with reference to the accompanying drawings and examples. The embodiments of the present invention include but are not limited to the following examples.

[0052] Example

[0053] like Figures 1 to 12 As shown, the super aeration flotation system includes a reaction tank 1, an inclined guide plate 2 arranged on the inner wall of the reaction tank, a dished tank 3 arranged at the bottom of the reaction tank and arranged in a ring shape with its center, a central island 4 formed by the inner ring part of the dished tank protruding from the bottom of the reaction tank, an aeration mechanism 5 arranged on the central island and connected to the outside through a pipe 25, a transmission mechanism 6 installed above the reaction tank through an external bracket, a central transmission rod 7 arranged along the axis of the reaction tank and connected to the output end of the transmission mechanism, a stirring blade 8 arranged on the central transmission rod and located in the reaction tank, a dynamic settler 10 arranged at an upper position in the reaction tank and connected to the central transmission rod, and an overflow port 9 provided on the side wall of the reaction tank to match the dynamic settler.

[0054] Specifically, the reaction tank, as the basic carrier of the entire system, is usually designed as a cylindrical structure to ensure that the flow and reaction of the material in the tank are relatively uniform. Its material is selected from materials with good corrosion resistance, such as rubber-lined carbon steel or fiberglass. For large-scale wet phosphoric acid production equipment, considering the combined needs of strength and corrosion resistance, rubber-lined carbon steel is a more suitable choice; for some small-scale application scenarios or occasions with weight requirements, fiberglass can also be selected. The size of the reaction tank depends on the actual production scale. For example, in large-scale production, the diameter often ranges from 5 to 10 meters, and the height is between 6 and 10 meters.

[0055] Inclined guide plates include two types: downward-flipping guide plates 21 and upward-pressure guide plates 22. These differ primarily in their mounting location and form, though their materials and basic structure can be the same. For example, corrosion-resistant 316L stainless steel can be used to ensure long-term stable operation in highly corrosive reaction fluids. The downward-flipping guide plates 21 and upward-pressure guide plates 22 are installed in a counter-rotating spiral pattern at the upper and lower ends of the reaction tank's inner wall, respectively. Each guide plate is multi-directionally inclined. For example, the slope inclination angle (equivalent to the spiral rise angle) between the head and tail ends of the downward-flipping guide plate 21 and the upward-pressure guide plate 22 is 15° to 60°, preferably 45°, which is represented by a in the figure; the inclination angle of the downward-flipping guide plate relative to the vertical direction of the inner wall to the stirring direction is 0° to 30°, preferably 15°, which is represented by b in the figure; the inclination angle of the upward-pressure guide plate relative to the vertical direction of the inner wall to the stirring direction is 0° to 30°, preferably 15°. The specific inclination angles of the two are adjusted and configured according to the actual production process, and can be the same or different.

[0056] The downward-turning guide plates and upward-pressure guide plates are both intermittently connected to the inner wall of the reaction tank through multiple connecting rods 24, so that a gap is maintained between the inner edge of the guide plate and the inner wall of the reaction tank. This gap can be flexibly adjusted according to actual production needs and factors such as liquid flow rate, and is usually maintained in the range of 1 to 15 cm. In this embodiment, the downward-turning guide plates and upward-pressure guide plates are both configured as 4, and an appropriate gap should be maintained between the ends of adjacent guide plates. Therefore, the projected length of each guide plate in the direction of the axis of the reaction tank is approximately 1 / 4 of the circumference of the reaction tank. In addition, a plurality of guide plate through holes 23 are evenly opened on the downward-turning guide plates and the upward-pressure guide plates, with an opening rate of 10% to 40%, preferably 35%, to enhance the turbulence when the gas and liquid pass through, thereby improving the mixing effect of the reaction system.

[0057] In a dished aeration structure, the dished trough is formed by special machining of the reactor bottom, using the same or matching corrosion-resistant material. During machining, a dished structure with a central ring is formed at the bottom of the reactor, using either pre-machined preforming or a stacking and filling process, based on pre-designed dimensions. The depth of the dished trough is determined by the installation height of the aeration mechanism, which also takes into account the overall spatial layout within the reactor. For an aeration mechanism installation height of 0.5 meters, the dished trough depth is configured to be 1 meter. The trough opening width is machined to 60% to 95% of the reactor's internal radius. For a 3-meter internal radius, the dished trough width ranges from 1.8 to 2.85 meters. The specific dimensions are determined by calculations of the material momentum within the tank during design. After machining, the dished trough surface is polished and treated with an anti-corrosion treatment to ensure a smooth surface with excellent corrosion resistance, thereby reducing flow resistance and effectively preventing corrosion. The central island is formed by the inner ring part of the dished trough protruding at the bottom of the reaction tank. Its height and diameter are designed according to the size and stability requirements of the aeration mechanism. Its height is usually slightly higher than the aeration mechanism, and its diameter is slightly larger than the diameter of the aeration distribution ring.

[0058] The aeration bracket 26 is made of 316L stainless steel and is securely fastened to the center island by welding or bolting, depending on the shape and size of the center island. The aeration distribution ring 27 is also made of 316L stainless steel and securely mounted to the aeration bracket by welding or auxiliary fasteners. Its inlet is connected to a pipeline via welding or flange connection, facilitating access to external air supply or pre-aeration / superaeration of aerated materials. The aeration distribution ring is designed with two outlet structures to accommodate direct aeration and pre-aeration / superaeration refeed conditions, which may occur in the wet-process phosphoric acid superaeration flotation process. For direct aeration, multiple holes are uniformly positioned on the aeration distribution ring according to the designed locations, and aeration nozzles 28 are installed. To ensure more uniform gas distribution, a flow guide or flow equalization structure can be added to the aeration distribution ring. The aeration nozzles 28 are evenly distributed at the designed locations on the bottom of the aeration distribution ring, facing downward. The number of aeration nozzles 28 is determined by the reactor size and aeration requirements, generally ranging from 10 to 30. Each outlet of the aeration nozzle can be configured with a specific conical shape and size. After the gas is ejected, it can form a uniformly diffused bubble stream, thereby enhancing the agitation effect and circulation efficiency of the liquid. For the pre-aeration / superaeration and re-feeding operation, multiple holes are uniformly opened in the aeration distribution ring according to the designed positions, and a tubular aeration outlet structure 29 is installed. The size of the holes opened here is generally larger than the holes opened in the previous operation structure. In addition, the inner diameter of the aeration distribution ring and the corresponding inner diameter of the pipeline can be larger to facilitate smoother access to the gas-containing material that has been pre-aerated / superaerated in the previous stage.

[0059] Regarding the dynamic settler, the dynamic settler includes a first settling mechanism 11 and a second settling mechanism 12 connected to the central transmission rod and arranged side by side in an upper and lower manner, and a plurality of positioning connectors 13 arranged between the first settling mechanism and the second settling mechanism. Specifically, the first settling mechanism 11 includes an upper splint 14 and a lower splint 15 arranged in parallel, a plurality of folding connectors 16 densely arranged between the upper splint and the lower splint, a foam settling channel 17 formed between adjacent folding connectors, and settling holes opened on the upper splint and the lower splint and connected to the foam settling channel. Among them, the upper splint 14 and the lower splint 15 can be made of 316L stainless steel plates with a thickness of 3 to 5 mm, and are cut into a shape matching the interior of the reaction tank using laser cutting technology. The folding connector 16 is made of 316L stainless steel and is formed into a specific fold line shape by die stamping. The length and angle are designed to match the distance between the upper and lower splints and the expected shape of the foam sedimentation channel. For example, the length is between 5 and 10 cm, and the fold line angle is within the range of 120° to 150°. Using a welding process, the folding connector is tightly fixed between the upper and lower splints, and the spacing between adjacent folding connectors is maintained at 2 to 5 cm, thereby constructing the foam sedimentation channel 17. According to the designed foam sedimentation channel, settlement holes are pre-opened on the upper and lower splints to ensure that the position of the settlement holes matches the foam sedimentation channel formed by the folding connector. Laser drilling technology can be used to ensure the accuracy and opening rate of the holes are consistent. The opening rate of the settlement holes is controlled at 30% to 40%, preferably 36%. The hole diameter is determined according to actual conditions, generally between 5 and 30 mm. The settlement holes are regularly arranged along the foam sedimentation channel to ensure a stable treatment effect on the foam.

[0060] The structure of the second sinking mechanism 12 is the same as that of the first sinking mechanism, but the porosity of the sinking holes on the second sinking mechanism is smaller than that of the sinking holes on the first sinking mechanism, usually between 25% and 35%, preferably 28%. According to the actual application, the aperture of the sinking holes on the second sinking mechanism may also be appropriately smaller than the aperture of the sinking holes on the first sinking mechanism. Then, the second sinking mechanism is installed side by side on the first sinking mechanism using a positioning connector 13, such as a high-strength bolt, while ensuring that the spacing between the two is not less than their respective thicknesses. For example, when the total thickness is 8 to 10 cm, the spacing should be set to 10 to 12 cm. During the installation process, ensure that the two sinking mechanisms remain concentric and the center reference level.

[0061] The central transmission rod 7 can be made of a corrosion-resistant, high-strength alloy. Its diameter is designed based on the size of the reaction tank and the weight of related components such as the agitator blades and dynamic settler, typically ranging from 5 to 20 cm. To further facilitate foam collection, a rotating foam collector 18 is located above the second settling mechanism and corresponding to the overflow port on the central transmission rod. This rotating foam collector comprises multiple arms 31 evenly spaced around the central transmission rod, and foam scrapers 32 at the ends of the arms. The length of the arms matches the inner radius of the reaction tank. The curved arms 31 of the rotating foam collector 18 can be made of the same material as the central transmission rod and forged into an arc shape. The outer arc runs in the direction of rotation, and the chord length of the arms matches the inner radius of the reaction tank. The ends of the arms should maintain a slight gap from the inner wall of the reaction tank to avoid direct contact with the inner wall. The arms themselves can be longer due to the curvature of the arc to ensure full coverage of the tank during rotation. The arms are evenly spaced around the central transmission rod and typically number 4 to 6. The scraper head 32 consists of a stainless steel scraper backing plate, a scraper base plate and a scraper baffle made of soft polytetrafluoroethylene (PTFE) sheet. The scraper backing plate can be made of a 5-8 mm thick plate and is welded or bolted to the end of the rotary arm to provide sufficient support strength. The scraper base plate and scraper baffle are configured to corresponding thicknesses and connected to the scraper backing plate by bonding or bolting, forming a stable L-shaped structure. When installed, the scraper head should maintain an appropriate distance from the inner wall of the reaction tank, generally 2-5 mm, to effectively scrape foam without excessive friction damage.

[0062] The transmission mechanism 6 can adopt the traditional driving structure of the stirring reaction tank, which is usually a combination of a motor and a reducer. In the present invention, the transmission can be adapted according to the dynamic settler added in the design, thereby improving the efficient collection and processing of foam while ensuring the reaction efficiency through stirring.

[0063] An overflow port 9 is located on the sidewall of the reaction tank, corresponding to the position of the rotating foam collector in the dynamic settler. The overflow port's dimensions are designed based on the flow rate of foam scraped from the dynamic settler to ensure timely and smooth foam discharge. The overflow port's edge can be fitted with a baffle to prevent foam overflow, and can also be equipped with valves and other components to control foam discharge based on actual production conditions.

[0064] The present invention employs a spiral arrangement of inclined guide plates, coupled with a specific inclination angle, through-hole design, and spaced connection with the inner wall, which together constitute key factors in optimizing liquid flow and material mixing. The disc-shaped aeration structure formed by the aeration mechanism and disc-shaped troughs ensures uniform and efficient aeration through the design and matching of the disc-shaped trough depth and width, in conjunction with the layout design of the aeration mechanism, aeration distribution ring, and aeration nozzle / aeration outlet structure. The design of the folding connectors, foam settling channels, and settling hole opening ratios of the first and second settling mechanisms in the dynamic settler, combined with the design of the rotary arm and scraper head of the rotating foam collector, effectively resolves the problem of foam accumulation. The interaction of these various structures forms an organic whole, comprehensively optimizing the wet-process phosphoric acid production process.

[0065] Based on the structure of the aforementioned super aeration floatation system, the present invention also provides a method for implementing the super aeration floatation system, which specifically includes the following steps:

[0066] 1. Preparation before system startup

[0067] The equipment inspection process must be comprehensive and detailed, covering all key components such as the reaction tank, inclined guide plate, disc-shaped aeration structure, dynamic settler and overflow port, to ensure that each component is undamaged and the connection is firm and reliable, especially to check whether the pipe connection of the aeration mechanism is sealed and whether the transmission components of the dynamic settler are flexible.

[0068] Material Preparation: Prepare the raw materials required for wet-process phosphoric acid production, such as phosphate rock slurry and sulfuric acid, and ensure that their quality and purity meet production requirements. Also, verify the operational status of the feeding equipment to ensure it can accurately deliver the raw materials to the reaction tank.

[0069] Gas Supply Preparation: Check the external gas supply system to ensure it can stably provide gas at the required pressure and flow rate to meet the aeration needs of the aeration mechanism. To ensure the safety of the gas supply pipeline, strict air tightness testing must be performed to avoid the risk of gas leakage. When the aeration mechanism is used for pre-aeration (or super-aeration) and then feeding, the external gas supply system is connected to the aeration / super-aeration equipment in the previous process, which then feeds the treated gas-containing material into the corresponding aeration mechanism.

[0070] 2. Reaction liquid feeding and initial aeration

[0071] In direct aeration operation, pre-treated phosphate rock slurry and sulfuric acid, along with other reactants, are delivered to the reaction tank in a specific ratio through a feed pipe. Once the materials enter the tank, a transmission mechanism drives the agitator blades to mix them. Inclined guide plates on the inner wall of the tank enhance the mixing process.

[0072] At the same time, the aeration mechanism installed on the central island begins operation. External air is smoothly piped into the aeration distribution ring. It is then finely sprayed downward from nozzles evenly distributed across the ring's base. As the bubbles slowly rise, they effectively agitate the reaction liquid, achieving initial and even mixing, thus smoothly initiating the reaction between the phosphate rock and sulfuric acid. The unique design of the disc-shaped trough guides the aerated liquid into a circular flow pattern, further optimizing mixing within the reaction tank.

[0073] On the other hand, when feeding in the pre-aeration / superaeration and re-feeding condition, since the reaction materials such as phosphate rock slurry and sulfuric acid have been processed into gas-containing materials in the previous aeration / superaeration equipment, the gas-containing materials are directly transported by the pipeline connected to the aeration mechanism, enter the reaction tank through the aeration distribution ring and the aeration outlet structure, and guide the liquid to form a circular flow pattern from the disc-shaped groove at the bottom of the reaction tank. When the gas-containing material in the reaction tank reaches a certain level, the transmission mechanism drives the stirring blades to stir and mix the gas-containing material in the reaction tank, thereby comprehensively enhancing the stirring and mixing effect of the materials in the reaction tank.

[0074] 3. Reaction solution circulation and mixing enhancement

[0075] Guide plates guide circulation: The flow field formed by the agitated liquid within the reaction tank creates multiple eddies and turbulence upon contact with the inclined guide plates, continuously shifting flow patterns and promoting material mixing and reaction. The downward-turning guide plates tilt the upper layer of reaction liquid downward along a spiral path, while the upward-pressing guide plates press the lower layer upward along an opposite spiral path. The intersection of the two forms a three-dimensional circulation path within the tank, further evenly mixing the materials during circulation, avoiding local concentration differences and effectively increasing the reaction rate.

[0076] Continuous Aeration and Mixing: In direct-aeration aeration, the aeration mechanism operates continuously. As the reaction liquid circulates, bubbles are more evenly distributed throughout the reaction tank, continuously providing the required oxygen for the reaction and promoting more complete contact and reaction between the phosphate rock slurry and sulfuric acid. In pre-aeration / superaeration and re-feeding, the aeration mechanism continuously introduces aerated material. The circulating reaction liquid promotes more even mixing and distribution of gases within the aerated material. The ingenious coordination between the disc-shaped tank and the aeration mechanism significantly enhances the circulation dynamics of the reaction liquid and ensures uniform distribution of the reaction liquid within the reaction tank.

[0077] 4. Dealing with over-aeration and foam generation

[0078] In direct-supply aeration, the aeration volume is appropriately increased based on production process requirements, entering the superaeration stage. At this point, a large amount of gas rapidly flows into the reaction tank, further enhancing the mixing effect of the reaction liquid, but this can also cause a large amount of foam to form within the reaction tank for a short period of time. In pre-aeration / superaeration followed by feeding, the aeration and superaeration processes are carried out by the preceding aeration / superaeration equipment. However, the process and the process conditions achieved after the gas-laden material is fed into the reaction tank are similar to those of direct-supply aeration.

[0079] During the foam treatment process, as foam is generated and increases within the reaction tank, the dynamic settler becomes increasingly effective, causing a large amount of foam to rise to the top of the tank. The foam first flows into the primary settling mechanism, which utilizes parallel upper and lower plates, their settling holes, and a foam settling channel formed by folding connectors between them to initially break up and settle the foam, thereby achieving a preliminary separation of gas and liquid.

[0080] 5. Further processing and discharge of foam

[0081] Secondary Settling Stage: The foam, initially treated by the first settling mechanism, continues to rise and enters the second settling mechanism for further treatment. The settling holes in the second settling mechanism have a smaller opening ratio than the first settling mechanism, which further separates and settles the foam, improving the gas-liquid separation effect.

[0082] Foam Collection and Discharge: The remaining foam after two stages of settling is collected by a rotating foam collector located above the second settling mechanism. Driven by a central transmission rod, the rotating foam collector's evenly distributed arc-shaped arms and the L-shaped scraper head at their ends rotate synchronously, effectively scraping off residual foam and discharging it out of the reaction tank through an overflow port matched with the dynamic settler. This ensures that the foam in the reaction tank is effectively controlled, maintaining sufficient reaction space and stable reaction progress.

[0083] 6. Discharge of reaction products

[0084] Reaction completion determination: Continuously monitor the reaction progress within the reaction tank and determine whether the reaction is complete by testing parameters such as the composition, temperature, and pressure of the reaction solution. When all parameters meet the pre-set reaction termination conditions, the wet-process phosphoric acid production reaction is complete.

[0085] Discharge: After the reaction is completed, the generated phosphoric acid, phosphogypsum and remaining reaction liquid are discharged from the reaction tank through the discharge pipe and then enter a series of subsequent processing steps such as separation and purification.

[0086] 7. System maintenance and cleaning

[0087] Regular inspections: During system operation, the status of various components must be regularly inspected, including but not limited to the secure connection of the inclined guide plates, the effectiveness of the disc aeration structure, and the smooth operation of the dynamic settler. Also, check that the overflow port is unobstructed to prevent blockage.

[0088] Cleaning and Maintenance: Based on production conditions and equipment operation status, the reaction tank should be cleaned regularly to remove impurities and scale adhering to the tank wall, guide plates, aeration mechanism and other components to ensure the performance of each component and the operating efficiency of the system. Worn or damaged components should be replaced in a timely manner to ensure long-term stable operation of the system.

[0089] By combining the above structural design with the wet-process phosphoric acid process, the present invention exhibits the following technical advantages:

[0090] 1. Optimizing aeration and mixing effects: The disc-shaped aeration structure design makes aeration more uniform and efficient. The aeration mechanism is located in the center island, and downward aeration is achieved through aeration nozzles. Combined with the shape of the disc-shaped tank, it guides the aerated reaction liquid into a good circulation flow. This circulation pattern makes the oxygen distribution in the reaction liquid more uniform, promotes full contact between the phosphate rock and sulfuric acid, and greatly improves the reaction efficiency. At the same time, the inclined guide plate further enhances the mixing of the liquid. The downward-turning and upward-pressing guide plates work together to form a three-dimensional circulation path, ensuring the thorough mixing of the materials in the reaction tank, thereby eliminating local concentration unevenness and further improving the uniformity of the reaction. According to actual tests, compared with traditional reaction systems, this system has increased reaction efficiency by 20% to 40% and the uniformity of the reaction system by 25% to 35%.

[0091] 2. Effectively separate the foam problem: The setting of the dynamic settler effectively solves the problem of foam accumulation in the upper part of the reaction tank during the super-exposure process. The first settling mechanism and the second settling mechanism gradually separate and settle the foam through the foam settling channels formed by settling holes with different opening rates and folding connectors, so that the gas and liquid in the foam are fully separated. The rotating foam collector further scrapes off the residual foam and discharges it through the overflow port to ensure that there is enough effective space in the reaction tank for reaction. Practical application has proved that after the introduction of this system, the problem of foam accumulation has been significantly curbed, and the effective utilization rate of the reaction space can be increased to between 20% and 30%, thereby ensuring the efficiency and stability of the reaction process.

[0092] 3. Improved Product Quality and Yield: Thanks to uniform aeration, thorough mixing, and effective solution to foaming issues, the production quality and yield of phosphoric acid and phosphogypsum have been significantly improved. A more complete reaction significantly reduces impurities in these products, stabilizing their composition and improving their application in various fields, including construction and chemical engineering. Furthermore, this increased reaction efficiency directly leads to increased production. Within the same production timeframe, phosphoric acid and phosphogypsum production can increase by 25% to 35%, resulting in higher economic benefits for the company.

[0093] 4. Enhanced Equipment Stability and Lifespan: The rational design and coordinated operation of the inclined guide plate, disc-shaped aeration structure, and dynamic settler reduce impact and wear on the equipment during the reaction process. For example, uniform aeration and liquid flow reduce erosion of the reaction liquid against the inner wall of the reaction tank, and the dynamic settler effectively prevents foam damage to the equipment. This enhances the stability of the equipment and extends its service life.

[0094] 5. Environmental Protection and Sustainability: This system avoids the use of traditional defoaming agents, reduces potential environmental pollution, and complies with environmental protection requirements. At the same time, by improving production efficiency and product quality, it achieves more efficient use of resources and has good sustainability.

[0095] In summary, the present invention demonstrates significant advantages in phosphogypsum production, can comprehensively improve production efficiency, product quality, equipment stability and environmental performance, and provides an innovative solution for the wet-process phosphoric acid production industry.

[0096] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any changes that adopt the design principles of the present invention and any changes made through non-creative work on this basis should fall within the scope of protection of the present invention.

Claims

1. A super aeration flotation system, characterized in that: The invention comprises a reaction tank (1), an inclined guide plate (2) arranged on the inner wall of the reaction tank (1), a dish-shaped tank (3) arranged at the bottom of the reaction tank (1) and arranged in a ring shape at its center, a central island (4) formed by the inner ring portion of the dish-shaped tank (3) protruding from the bottom of the reaction tank (1), an aeration mechanism (5) arranged on the central island (4) and connected to the outside through a pipeline, a transmission mechanism (6) installed above the reaction tank (1) through an external bracket, a central transmission rod (7) arranged along the axis of the reaction tank (1) and connected to the output end of the transmission mechanism (6), a stirring blade (8) arranged on the central transmission rod and located in the reaction tank, a dynamic settler (10) arranged at an upper position inside the reaction tank (1) and connected to the central transmission rod (7), and an overflow port (9) arranged on the side wall of the reaction tank (1) and matching the dynamic settler (10); The aeration mechanism (5) comprises an aeration support (26) mounted on the bottom of the reaction tank (1), an aeration distribution ring (27) mounted on the aeration support (26) and connected to an external pipeline, and a plurality of aeration nozzles (28) or aeration outlet structures (29) uniformly distributed on the aeration distribution ring (27). The aeration nozzles (28) or aeration outlet structures (29) are arranged at the bottom of the aeration distribution ring (27) facing downward and matching the disc-shaped tank (3). The aeration nozzles are used for direct air supply aeration working conditions, and the aeration outlet structures are used for pre-aeration / superaeration and re-feeding working conditions. The inclined flow guide plates (2) comprise a plurality of downward-turning flow guide plates (21) arranged in a spiral shape along the upper portion of the inner wall of the reaction tank (1) and a plurality of upward-pressing flow guide plates (22) arranged in a spiral shape along the lower portion of the inner wall of the reaction tank (1), wherein the spiral arrangement directions of the downward-turning flow guide plates (21) and the upward-pressing flow guide plates (22) are opposite; the downward-turning flow guide plates (21) and the upward-pressing flow guide plates (22) are intermittently connected to the inner wall of the reaction tank (1) via a plurality of connecting rods, so that a gap is maintained between the inner edge of the flow guide plates and the inner wall of the reaction tank (1).

2. The super aeration floatation system according to claim 1, characterized in that: The depth of the disc-shaped groove (3) is 0.5 to 2.5 times the installation height of the aeration mechanism (5); the slot width of the disc-shaped groove (3) is 60% to 95% of the inner radius of the reaction tank (1).

3. The super aeration floatation system according to claim 1, characterized in that: The slope angle between the head and tail ends of the downward-turning guide plate (21) and the upward-pressure guide plate (22) is 15 to 60 degrees; the downward-turning guide plate (21) is inclined at 0 to 30 degrees relative to the vertical direction of the inner wall toward the stirring direction, and the upward-pressure guide plate (22) is inclined at 0 to 30 degrees relative to the vertical direction of the inner wall toward the stirring direction.

4. The super aeration floatation system according to claim 1, characterized in that: The downward-turning guide plate (21) and the upward-pressing guide plate (22) are evenly provided with a plurality of guide plate through holes (23), with an opening rate of 10% to 40%.

5. The super aeration floatation system according to any one of claims 1 to 4, characterized in that: The dynamic settler (10) comprises a first settling mechanism (11) and a second settling mechanism (12) connected to a central transmission rod (7) and arranged side by side in an upper and lower manner, and a plurality of positioning connectors (13) arranged between the first settling mechanism (11) and the second settling mechanism (12).

6. The super aeration floatation system according to claim 5, characterized in that: The first sedimentation mechanism (11) comprises an upper clamping plate (14) and a lower clamping plate (15) arranged in parallel, a plurality of folding connecting members (16) densely arranged between the upper clamping plate (14) and the lower clamping plate (15), a foam sedimentation channel (17) formed between adjacent folding connecting members (16), and sedimentation holes opened on the upper clamping plate (14) and the lower clamping plate (15) and connected to the foam sedimentation channel (17); the structure of the second sedimentation mechanism (12) is the same as that of the first sedimentation mechanism (11), but the opening rate of the sedimentation holes of the second sedimentation mechanism (12) is smaller than the opening rate of the sedimentation holes on the first sedimentation mechanism (11).

7. The super aeration floatation system according to claim 5, characterized in that: The central transmission rod (7) is provided with a rotating foam collector (18) located above the second sedimentation mechanism (12) and corresponding to the overflow port (9). The rotating foam collector (18) comprises a plurality of rotating arms (31) uniformly distributed around the circumference of the central transmission rod (7), and a foam scraping head (32) provided at the end of the rotating arms (31), wherein the length of the rotating arms (31) matches the inner radius of the reaction tank (1).

8. The method for implementing the super aeration floatation system according to any one of claims 1 to 7, characterized in that: The following steps are involved: S10. Preparation: Ensure that all components of the super aeration flotation system are intact and connected securely, that the raw materials are ready and the feeding equipment is functioning properly, and that the external air supply system is stable and the pipelines are airtight; S20, feeding and initial aeration: the material enters the reaction tank through the feeding pipe, while the central island aeration mechanism supplies air, and the disc-shaped tank guides the aeration liquid circulation to start the reaction; S30, Mixing Enhancement: Inclined guide plates guide the reaction liquid to form a three-dimensional circulation, combined with continuous aeration to promote uniform mixing and reaction of materials; S40, super aeration and initial foam treatment: Increase the aeration volume to enter super aeration, and the generated foam is initially separated into gas and liquid by the first settling mechanism of the dynamic settler; S50, secondary foam treatment and discharge: The initially treated foam enters the second settling mechanism for further separation and sedimentation, and is then scraped off by a rotating foam collector and discharged through an overflow port; S60, discharging: After monitoring and judging the completion of the reaction, the product is discharged through the discharge pipe and the discharging parameters are controlled.

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