A reactor dynamic settler

Abstract

The utility model discloses a kind of dynamic settler of reaction tank, including reaction tank body, first settlement structure being set in the upper position of reaction tank body, the center transmission rod being connected along the axial position of reaction tank body and first settlement structure by external transmission mechanism, and overflow outlet being set in the upper side wall of reaction tank body.The utility model passes through the specific dynamic settler structure design, makes the foam generated in the operation process of reaction tank super-exposure enter first settlement structure and is broken and settled by the cooperation of settlement channel and settlement hole, effectively handles foam accumulation problem, and the foam after preliminary treatment can also be handled by further configured second settlement structure and rotating foam collector, finally discharge through overflow outlet, to effectively solve the problem of foam accumulation and separation in reaction tank interior, improve production efficiency, ensure product quality.

Description

Technical Field

[0001] This utility model relates to equipment for wet-process phosphoric acid production, specifically to a dynamic settling device for a reaction tank. Background Technology

[0002] The wet-process phosphoric acid production method primarily uses sulfuric acid to decompose phosphate rock, causing a reaction that produces phosphoric acid and calcium sulfate. Through acid hydrolysis, filtration, and purification processes, phosphoric acid is separated from impurities. This process is mature and has a large production scale, but it faces challenges such as the treatment of phosphogypsum waste and improving product purity. The treatment of phosphogypsum solid waste has long been a difficult problem in this field. Currently, researchers have improved the process, enabling the wet-process phosphoric acid production not only to yield qualified phosphoric acid but also to produce phosphogypsum byproducts that meet industrial standards and reusable auxiliary materials, thus fundamentally solving the problem of difficult traditional phosphogypsum solid waste treatment.

[0003] In the wet-process phosphoric acid production process, the reaction tank, as the core equipment, plays a crucial role in the reaction of phosphate rock and sulfuric acid to produce phosphoric acid and phosphogypsum. However, in the entire production process, ultra-aeration, as one of the specific processes, although it has positive effects on accelerating the reaction rate, improving mass transfer efficiency, or promoting the formation of intermediate products, inevitably causes a series of problems, especially the accumulation of foam in the upper part of the tank, which has many adverse effects on phosphogypsum production.

[0004] Over-aeration is a process typically implemented to meet specific reaction requirements in wet-process phosphoric acid production. For example, it can improve reaction conditions and drive the reaction in the desired direction by accelerating reaction rates, improving mass transfer efficiency, or promoting intermediate product formation. However, over-aeration also causes a large amount of gas to rapidly enter the reaction tank. The interaction between the gas and the liquid in the tank significantly alters the surface tension of the liquid, resulting in the generation of a large amount of foam. Due to the complex gas-liquid environment within the reaction tank, these foams exhibit high stability and do not easily burst or disappear quickly, thus accumulating rapidly in the upper region of the reaction tank.

[0005] In terms of production efficiency, the excessive accumulation of foam at the top of the reaction tank severely restricts the space required for reaction and material flow. More importantly, the foam contains a large amount of harmful components that significantly impact the quality of phosphoric acid and phosphogypsum. This prevents the reaction between phosphate rock and sulfuric acid from proceeding fully in an ideal spatial environment, reducing the opportunities for contact and reaction between materials and thus lowering the reaction rate. For example, in some large-scale wet-process phosphoric acid production plants, the foam accumulation problem after over-aeration extends each production cycle by an average of 1-2 hours, significantly reducing the output per unit time, leading to a decline in overall production efficiency and a corresponding increase in production costs.

[0006] In terms of product quality, the presence of foam severely interferes with the critical liquid-solid-gas three-phase separation process during the reaction. Foam easily traps unreacted phosphate rock particles and already formed phosphogypsum particles, hindering their normal sedimentation and separation. Ultimately, these impurities are mixed into the phosphoric acid product along with the foam, leading to a decrease in phosphoric acid purity and affecting the quality stability of subsequent phosphate chemical products. For phosphogypsum, the increased impurity content also significantly reduces its quality, limiting its widespread application in building materials, agriculture, and other fields.

[0007] Currently, the industry has adopted various measures to address the problem of foam accumulation in reaction tanks after ultra-aeration. Some companies choose to add defoamers to solve the foam problem; however, this method has many drawbacks. The dosage of defoamers is difficult to control precisely; insufficient dosage will not effectively suppress foam, while excessive dosage may interfere with the extraction reaction, alter the chemical properties of the system, and ultimately affect product quality. Furthermore, long-term use of defoamers significantly increases production costs, and some defoamers are difficult to biodegrade naturally, posing a potential environmental pollution risk. Other companies have attempted to reduce foam generation by optimizing ultra-aeration process parameters, such as adjusting the gas introduction speed, time, and quantity. However, because the phosphogypsum production process involves the interaction of multiple complex factors, and the production conditions are constantly changing, this method is difficult to adapt to fluctuations in various production conditions in real time and effectively. The foam accumulation problem still occurs frequently, severely restricting the efficient and stable operation of wet-process phosphoric acid production. Utility Model Content

[0008] To address the problems of the prior art, this invention provides a dynamic settling device for reaction tanks, which effectively solves the problem of foam collection and removal through a settling structure design.

[0009] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0010] A dynamic settling device for a reaction tank includes a reaction tank body, a first settling structure disposed in the upper part of the reaction tank body, a central transmission rod connected to the first settling structure along the axis of the reaction tank body via an external transmission mechanism, and an overflow port disposed on the upper side wall of the reaction tank body.

[0011] Specifically, the first settling structure includes an upper clamping plate and a lower clamping plate arranged in parallel, a plurality of folded connectors densely arranged between the upper clamping plate and the lower clamping plate, a foam settling channel formed between adjacent folded connectors, and settling holes opened on the upper clamping plate and the lower clamping plate that communicate with the foam settling channel.

[0012] The opening ratio of the settling holes is 30% to 40%, preferably 36%.

[0013] This structural design guides the foam into the settling channel and accelerates the foam's rupture and settling through the settling channel and settling holes, allowing the liquid components in the foam to quickly flow back to the bottom of the reaction tank to participate in the reaction, reducing the accumulation of foam in the upper part of the tank.

[0014] Furthermore, a second settlement structure with the same structure is arranged side by side above the first settlement structure, and multiple positioning connectors are provided between the first settlement structure and the second settlement structure.

[0015] The opening ratio of the settling holes on the second settling structure is less than that on the first settling structure, generally 25% to 35%, preferably 28%.

[0016] Furthermore, the distance between the first settlement structure and the second settlement structure is not less than their own thickness.

[0017] This dual-layer settling structure design creates a gradient foam settling mode. The first settling structure initially treats a large amount of foam, reducing its quantity and volume. The second settling structure further refines the remaining foam, enhancing its settling effect and effectively preventing foam accumulation and overflow.

[0018] Furthermore, a rotating foam collector is provided on the central drive rod, which is located above the second settling structure and corresponds to the overflow port position.

[0019] Specifically, the rotating foam collector includes multiple rotating arms evenly distributed around a central drive rod, and a foam scraper head disposed at the end of the rotating arms, wherein the length of the rotating arms matches the inner diameter of the reaction tank body.

[0020] Specifically, the rotating arm is arc-shaped, with one side of its outer arc aligned with the direction of rotation.

[0021] Specifically, the shaving head includes a shaving base plate connected to the end of the rotating arm, a shaving back plate connected to the end of the rotating arm and forming an L-shape with the rear side of the shaving base plate, and a shaving baffle disposed at the end of the shaving base plate, wherein the shaving base plate and the shaving baffle are both made of polytetrafluoroethylene soft sheet, and the shaving back plate is a steel structure.

[0022] Driven by an external transmission mechanism, the central transmission rod rotates, causing the rotating foam collector to rotate synchronously. The foam scraper head scrapes the foam that has not completely settled to the overflow port for discharge, thus ensuring efficient removal of foam in the reaction tank.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) This utility model effectively addresses the foaming problem during the operation of the reaction tank through a cleverly designed dynamic settling device structure. Specifically, foam generated by overexposure first flows into the first settling structure, undergoing initial crushing and settling. After the first stage of treatment, the foam continues to flow into the second settling structure for more thorough and in-depth treatment. Finally, a rotating foam collector scrapes off any remaining foam and discharges it from the system through an overflow port. This not only solves the problem of foam accumulation inside the reaction tank but also significantly improves production efficiency, ensures product quality, and reduces damage to related equipment.

[0025] (2) The dynamic settling device of this utility model also fully considers the stability and durability of the equipment. The vertical spacing between the first and second settling structures ensures that the foam can be evenly distributed and settle in a gradient during settling, and prevents equipment damage caused by excessive local pressure. At the same time, by configuring the foam scraper base plate and foam scraper baffle to be made of polytetrafluoroethylene soft sheet, the wear resistance and corrosion resistance of the components are guaranteed, and they can withstand the scouring of foam for a long time without being easily damaged. The steel structure of the foam scraper back plate provides sufficient strength and stability, ensuring the stability and reliability of the rotating foam collector during the rotation process. Attached Figure Description

[0026] Figure 1 This is a side view of an embodiment of the present invention.

[0027] Figure 2 This is a schematic diagram of the top surface structure of an embodiment of the present invention.

[0028] Figure 3 This is a schematic diagram of the two settlement structures in an embodiment of the present invention.

[0029] Figure 4 This is a schematic diagram of the first settling structure in an embodiment of the present invention.

[0030] Figure 5 This is a schematic diagram of the structure of the skimmer head in an embodiment of this utility model.

[0031] The component names corresponding to the reference numerals in the attached drawings are as follows:

[0032] 1-Reaction tank body, 2-Central drive rod, 3-Overflow port, 10-First settling structure, 11-Upper clamping plate, 12-Lower clamping plate, 13-Folded connector, 14-Foam settling channel, 20-Second settling structure, 21-Positioning connector, 30-Rotating foam collector, 31-Rotating arm, 32-Foam scraper head, 33-Foam scraper bottom plate, 34-Foam scraper back plate, 35-Foam scraper baffle. Detailed Implementation

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments. The embodiments of the present invention include, but are not limited to, the following embodiments.

[0034] Example

[0035] like Figures 1 to 5 As shown, the dynamic settling device for the reaction tank includes a reaction tank body 1, a first settling structure 10 located at the upper part of the reaction tank body, a second settling structure 20 arranged side-by-side above the first settling structure, multiple positioning connectors 21 located between the first and second settling structures, a central transmission rod 2 connected to the first and second settling structures along the axis of the reaction tank body via an external transmission mechanism, an overflow port 3 located on the upper side wall of the reaction tank body, and a rotating foam collector 30 located above the second settling structure, corresponding to the overflow port and connected to the central transmission rod. The design of this dynamic settling device aims to improve reaction efficiency, reduce foam accumulation, optimize the production process, and ensure stable equipment operation and extended service life.

[0036] Specifically, the reaction vessel body is typically configured as a cylinder to facilitate uniform mixing and thorough reaction of materials within it. To adapt to different production environments and requirements, the reaction vessel body can be made of corrosion-resistant materials.

[0037] The first settling structure 10 includes an upper clamping plate 11 and a lower clamping plate 12 arranged in parallel, a plurality of folded connectors 13 densely arranged between the upper and lower clamping plates, foam settling channels 14 formed between adjacent folded connectors, and settling holes opened on the upper and lower clamping plates that communicate with the foam settling channels. The design of the first settling structure aims to achieve the initial settling and breakup of foam through physical structure, laying the foundation for subsequent gas-liquid separation.

[0038] Both the upper and lower clamping plates, as key components of the first settling structure, can be made of 316L stainless steel plates with a thickness of 3-5 mm. 316L stainless steel, a molybdenum-based austenitic stainless steel, exhibits excellent corrosion resistance not only in atmospheric and other mild environments, but also in sulfuric acid solutions and high-temperature conditions. Its resistance to pitting and crevice corrosion is further enhanced by the presence of molybdenum, chromium, and nitrogen, making it particularly suitable for long-term stable operation in harsh environments such as reaction tanks. Through laser cutting and other processes, the stainless steel plates are machined into a circular shape that fits the interior of the reaction tank, reducing the possibility of foam leakage.

[0039] The folded connector is also made of 316L stainless steel and is formed into a specific folded shape by die stamping. Its length and angle are designed to match the distance between the upper and lower clamping plates and the expected shape of the foam settling channel. For example, the length of the folded connector is between 5 and 10 cm, and its fold angle is maintained within the range of 120° to 150° to guide the foam to form a specific flow path within the channel, promoting gas-liquid separation. The folded connector can be densely fixed between the upper and lower clamping plates using welding or other fixed connection methods, maintaining a spacing of 2 to 5 cm between adjacent folded connectors, thereby forming a stable foam settling channel.

[0040] Settling holes are pre-drilled on the upper and lower clamping plates according to the designed foam settling channel. This ensures that the position of the settling holes matches the foam settling channel formed by the folded connector. Laser drilling technology can be used to ensure the accuracy and consistency of the hole opening ratio. The opening ratio of the settling holes is controlled between 30% and 40%, preferably 36%. The diameter of the holes is determined according to the actual situation, generally between 5 and 30 mm, to ensure that the foam can pass through smoothly and at the same time play a preliminary role in breaking up the foam. The settling holes are arranged on the upper and lower clamping plates according to the positional pattern of the foam settling channel to ensure the stable foam treatment effect of the entire settling structure. Finally, the first settling structure is installed in the upper part of the reaction tank body. It can be installed directly by supporting the central drive rod, or it can be supported by the central drive rod and the corresponding protrusion structure set on the inner wall of the reaction tank body for edge support. As for the specific connection method between the first settling structure and the central drive rod, it can be a fixed connection such as welding or bolt fastening, or a movable connection such as a rotatable connection of bearings and bearing seats. The main purpose is to ensure that the central drive rod has a stable supporting effect on the first settling structure. The specific connection method is not limited.

[0041] The structure and materials of the second settling structure are basically the same as those of the first settling structure, the main difference being the opening ratio of the settling holes. Specifically, the opening ratio of the settling holes on the second settling structure is less than that on the first settling structure, typically 25%–35%, preferably 28%. Depending on the actual application, the diameter of the settling holes on the second settling structure can also be appropriately smaller than that on the first settling structure. Then, using positioning connectors 21 (such as high-strength bolts), the second settling structure is installed side-by-side on top of the first settling structure, ensuring that the distance between them is not less than their respective thicknesses. For example, if the total thickness of the settling structures is 8–10 cm, the distance should be at least 10–12 cm to ensure a smooth transition of foam between the two settling structures and to reserve sufficient space for subsequent processing. During installation, the concentricity and parallelism of the two settling structures should be maintained as much as possible to ensure that the foam can smoothly enter the second settling structure from the first settling structure for secondary processing.

[0042] The central drive rod 2 can be made of corrosion-resistant high-strength alloy steel. Its diameter is designed according to the size of the reaction tank body, the two settling structures, the rotating foam collector, and the weight of related structures, and is generally between 5 and 20 cm. The upper end of the central drive rod is connected to an external transmission mechanism via a coupling to receive the drive. The two settling structures and the rotating foam collector are installed at the middle position of the upper part of the reaction tank body, and the lower end is usually used in conjunction with the stirring device of the reaction tank body.

[0043] The rotating foam collector 30 consists of multiple rotating arms 31 evenly distributed around the central drive rod. Each rotating arm is equipped with a foam scraper head 32, and the overall length of the rotating arms matches the inner radius of the reaction tank body. The rotating foam collector is designed to efficiently collect and discharge the foam remaining in the reaction tank body after sedimentation and separation through rotational motion, so as to maintain the smooth progress of the reaction process.

[0044] The rotating arms can be made of the same material as the central drive rod, and are forged into an arc shape. The outer arc side of the rotating arm is along the direction of rotation, which helps to better guide the foam towards the skimmer head during rotation. The overall length of the rotating arm after forming the arc shape can match the inner radius of the reaction tank body, that is, the chord length of the arc-shaped rotating arm is kept at a level comparable to the inner radius of the reaction tank body. At the same time, the end should maintain a slight gap with the inner wall of the reaction tank body to avoid direct contact with the inner wall of the tank. The length of the rotating arm itself can be longer due to the curvature of the arc, ensuring that the entire area inside the tank is fully covered during rotation. The rotating arms are evenly distributed around the central drive rod, and the number is determined according to the size of the reaction tank, generally 4 to 6. The spacing angle between adjacent rotating arms is equal to ensure the stability of rotation.

[0045] The skimmer head consists of a skimmer base plate 33, a skimmer back plate 34, and a skimmer baffle 35. The skimmer back plate is a 5-8mm thick steel plate, which is welded or bolted to the end of the rotating arm to provide sufficient strength and support for the skimmer head. The skimmer base plate and skimmer baffle can be made of polytetrafluoroethylene (PTFE) flexible sheets of appropriate thickness (e.g., 3-5mm), which are connected to the skimmer back plate by adhesive bonding or bolting to form a stable L-shaped structure. During installation, the skimmer head maintains an appropriate distance from the inner wall of the reaction tank, generally 2-5mm, which effectively removes foam without causing excessive friction damage.

[0046] The external transmission mechanism can adopt the traditional drive structure of a reaction tank agitator, typically a combination of a motor and a reducer. Specifically, it can be adapted to the addition of a settling structure and a rotating foam collector compared to the traditional structure, ensuring efficient foam collection and treatment while maintaining the reaction tank's agitation efficiency. For example, it can be integrated with automated control, using additional sensors to monitor the foam situation in the reaction tank in real time (e.g., detecting foam height via a level sensor). The signals are fed back to the control system, which automatically adjusts the motor's speed and rotation direction based on the signals, thereby improving the foam treatment effect.

[0047] Through the above structural design, the dynamic settling device of this utility model exhibits the following significant effects in the wet-process phosphoric acid production process.

[0048] In terms of foam separation efficiency, this dynamic settling device demonstrates excellent handling capabilities for foam accumulation caused by over-exposure. The combined design of the first and second settling structures, through settling channels formed by settling holes with varying open areas and folded connectors, achieves graded foam separation. First, the first settling structure, through settling holes with a 36% open area ratio, initially breaks up the foam, achieving preliminary gas-liquid separation. Then, the second settling structure, through settling holes with a 28% open area ratio, further compresses and settles the foam, significantly improving the gas-liquid separation effect. The rotating foam collector, utilizing its ingenious arc-shaped rotating arm design and skimmer head construction, efficiently removes residual foam after the two-stage settling process and smoothly discharges it from the tank. This not only effectively controls foam accumulation within the reaction tank but also ensures increased effective utilization of the reaction space, thereby significantly improving production efficiency. Practical applications show that compared to not using this high-efficiency dynamic settling device, production efficiency can be increased by 10% to 35%, and the production cycle is effectively shortened.

[0049] From the perspective of product quality improvement, the efficient removal of foam prevents unreacted phosphate rock particles or phosphogypsum particles from entering subsequent processes, significantly improving the purity of phosphoric acid. The wet-process phosphoric acid extraction and impurity reduction method significantly reduces the impurity content in phosphoric acid, laying a solid foundation for the high-quality production of subsequent phosphate chemical products. Simultaneously, the quality of phosphogypsum products is also improved; the reduced impurities allow for wider and more stable applications in building materials, agriculture, and other fields, thus significantly enhancing the product's market competitiveness.

[0050] In terms of equipment maintenance and lifespan extension, the solution to the foam buildup problem has played a significant protective role for the reaction tank and related equipment. Foam no longer frequently clogs pipes, valves, and other components, ensuring smooth operation of the production process, reducing equipment failure rates and unplanned shutdowns, which further enhances production continuity and overall stability.

[0051] In terms of economy and environmental protection, this utility model features a simple structural design, relatively low manufacturing and installation costs, and eliminates the need for defoamers that may pollute the environment. This reduces production costs while meeting environmental protection requirements. It achieves a good balance between economic and environmental benefits while improving production efficiency and product quality, bringing sustainable development advantages to enterprises.

[0052] The above embodiments are merely preferred embodiments of this utility model and are not intended to limit the scope of protection of this utility model. Any changes made based on the design principles of this utility model, or any non-creative changes made on this basis, shall fall within the scope of protection of this utility model.

Claims

1. A reactor dynamic settler, characterized in that, It includes a reaction tank body (1), a first settling structure (10) located in the upper part of the reaction tank body, a central transmission rod (2) connected to the first settling structure along the axis of the reaction tank body via an external transmission mechanism, and an overflow port (3) located on the upper side wall of the reaction tank body.

2. The reactor dynamic settler according to claim 1, characterized in that, The first settling structure (10) includes an upper clamping plate (11) and a lower clamping plate (12) arranged in parallel, a plurality of folded connectors (13) densely arranged between the upper clamping plate (11) and the lower clamping plate (12), a foam settling channel (14) formed between adjacent folded connectors (13), and settling holes opened on the upper clamping plate (11) and the lower clamping plate (12) that communicate with the foam settling channel (14).

3. The reactor dynamic settler according to claim 2, characterized in that, The opening ratio of the settling holes is 30% to 40%.

4. The reactor dynamic settler according to claim 3, characterized in that, Above the first settlement structure (10), a second settlement structure (20) with the same structure is arranged side by side, and multiple positioning connectors (21) are provided between the first settlement structure (10) and the second settlement structure (20).

5. The reactor dynamic settler according to claim 4, characterized in that, The opening ratio of the settling holes on the second settling structure (20) is less than that of the settling holes on the first settling structure (10).

6. The reactor dynamic settler according to claim 5, characterized in that, The distance between the first settlement structure (10) and the second settlement structure (20) is not less than their own thickness.

7. The reactor dynamic settler according to claim 6, characterized in that, The central transmission rod (2) is equipped with a rotating foam collector (30), which is located above the second settling structure (20) and corresponds to the overflow port (3).

8. The reactor dynamic settler according to claim 7, characterized in that, The rotating foam collector (30) includes multiple rotating arms (31) evenly distributed around the central drive rod (2) and a foam scraper (32) located at the end of the rotating arms (31), wherein the length of the rotating arms (31) matches the inner diameter of the reaction tank body (1).

9. The reactor dynamic settler according to claim 8, characterized in that, The rotating arm (31) is arc-shaped, with one side of its outer arc along the direction of rotation.

10. The reactor dynamic settler according to claim 9, characterized in that, The scraper head (32) includes a scraper base plate (33) connected to the end of the rotating arm (31), a scraper back plate (34) connected to the end of the rotating arm (31) and forming an L-shape with the rear side of the scraper base plate (33), and a scraper baffle (35) disposed at the end of the scraper base plate (33). The scraper base plate (33) and the scraper baffle (35) are both made of polytetrafluoroethylene soft sheet, and the scraper back plate (34) is a steel structure.

Images