Inorganic salt crystallization reaction apparatus

Abstract

The application relates to an inorganic salt crystallization reaction device, a stirring mechanism of which comprises a stirring rod, a first paddle and a second paddle, the stirring rod is rotatably arranged in a reaction container, the first paddle and the second paddle are connected with the stirring rod and located in a reaction cavity, and the first paddle and the second paddle are arranged at intervals along the axial direction of the stirring rod; the overflow container is provided with a second communication port, an overflow port and a precipitation cavity which are in communication, and the second communication port is in communication with the first communication port. Compared with the traditional technology, the inorganic salt crystallization reaction device mixes the raw materials in the reaction cavity sufficiently through the first paddle and the second paddle, so that the formation of inorganic salt crystals is facilitated, the overflow container is arranged to realize the continuity of the reaction process, the unreacted materials are prevented from being discharged too early, the nucleation, crystal nucleus growth and aging separation of inorganic salt nanoparticles are facilitated, the particle size distribution and purity of the inorganic salt crystals are ensured, and the crystallization efficiency of the inorganic salt crystallization reaction device and the quality of the inorganic salt crystal product are improved.

Description

Technical Field

[0001] This application relates to the technical field of inorganic salt crystallization, and in particular to an inorganic salt crystallization reaction apparatus. Background Technology

[0002] The design and optimization of inorganic salt crystallization reactors directly affect the quality of inorganic salt crystal products, production efficiency, and energy consumption. Traditional inorganic salt crystallization reactors operate in batches, with raw materials fed in at once and the inorganic salt crystal products discharged all at once after reacting to the endpoint under specific conditions. However, batch-operation inorganic salt crystallization reactors suffer from low crystallization efficiency and poor product quality stability, which in turn affects the production capacity and quality of inorganic salt crystal products. Utility Model Content

[0003] Therefore, it is necessary to provide an inorganic salt crystallization reaction device to address the problem of low crystallization efficiency in traditional technologies, which affects production capacity and product quality.

[0004] The technical solution is as follows:

[0005] One embodiment provides an inorganic salt crystallization reaction apparatus, comprising:

[0006] A reaction vessel having a feed inlet, a discharge outlet, a first connecting outlet, and a reaction chamber connected in series;

[0007] A stirring mechanism, comprising a stirring rod, a first impeller, and a second impeller, wherein the stirring rod is rotatably disposed on the reaction vessel, and the first and second impellers are both connected to the stirring rod and located within the reaction chamber, the first and second impellers being spaced apart along the axial direction of the stirring rod; and

[0008] An overflow container having a second connecting port, an overflow port, and a sedimentation chamber connected together, wherein the second connecting port is connected to the first connecting port.

[0009] In the aforementioned inorganic salt crystallization reaction apparatus, the raw materials are fed into the reaction chamber through the inlet of the reaction vessel. The stirring rod inside the reaction chamber rotates, driving the first and second impellers to stir the raw materials, thereby accelerating mixing and improving mixing uniformity. The mixed raw materials undergo a chemical reaction, ultimately generating inorganic salt crystals and mother liquor. The inorganic salt crystals settle at the bottom of the reaction vessel, while some inorganic salt crystals, driven by the mother liquor, sequentially enter the sedimentation chamber through the first and second connecting ports. The mother liquor and inorganic salt crystals in the sedimentation chamber experience minimal disturbance; the inorganic salt crystals settle at the bottom of the sedimentation chamber, while the mother liquor overflows from the overflow port. The precipitated inorganic salt crystals are returned to the reaction chamber, and the generated inorganic salt crystals are finally discharged through the discharge port to obtain the inorganic salt crystal product. Compared with traditional technology, the above-mentioned inorganic salt crystallization reaction device uses the first and second blades to fully mix the raw materials in the reaction chamber, which is conducive to the formation of inorganic salt crystals. The overflow container can realize the continuity of the reaction process and prevent unreacted materials from being discharged prematurely, which is conducive to the nucleation, crystal growth, and aging separation of inorganic salt nanoparticles, ensuring the particle size distribution and purity of inorganic salt crystals, thereby improving the crystallization efficiency of the inorganic salt crystallization reaction device and the quality of inorganic salt crystal products.

[0010] In one embodiment, the stirring rod extends axially along the depth direction of the reaction chamber, the second blade is arranged on the side of the first blade facing the bottom wall of the reaction chamber, the discharge port is opened on the bottom wall of the reaction vessel, and the feed port is arranged on the side of the first blade away from the second blade.

[0011] In one embodiment, the first communication port is opened on the side wall of the reaction vessel, the distance between the first blade and the bottom wall of the reaction chamber is set to D1, the distance between the second blade and the bottom wall of the reaction chamber is set to D2, and the distance between the first communication port and the bottom wall of the reaction chamber is set to D3, where D2 < D3 < D1.

[0012] In one embodiment, the height of the second connection port is lower than the height of the overflow port.

[0013] In one embodiment, one side wall of the sedimentation chamber is designated as a sedimentation wall, and the plane containing the sedimentation wall is set at an angle to the ground.

[0014] In one embodiment, the angle between the plane containing the sedimentation wall and the ground is set to α, where 45°≤α≤75°.

[0015] In one embodiment, the plane containing the first blade is set at an angle to the ground, and the plane containing the second blade is set at an angle to the ground.

[0016] In one embodiment, the angle between the plane containing the first blade and the ground is set to β, and the angle between the plane containing the second blade and the ground is set to γ, where β > γ.

[0017] In one embodiment, the reaction vessel includes a container body and a top cover, the container body having the reaction chamber, the top cover being assembled with the container body, and the feed inlet being located on the top cover.

[0018] In one embodiment, the stirring mechanism further includes a driving member disposed on the top cover and located outside the reaction chamber, and the stirring rod passes through the top cover and is drivenly connected to the driving member.

[0019] Compared with traditional technologies, the inorganic salt crystallization reaction apparatus of this application has the following advantages:

[0020] This invention features continuous production, large processing capacity, convenient operation, and significant processing effect. This device can continuously synthesize inorganic salt products with specific nanocrystalline structures, changing the reaction mode from single-reactor reaction to continuous reaction, effectively improving production efficiency and enhancing the quality of the final product. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the overall structure of an inorganic salt crystallization reaction apparatus in one embodiment of this application.

[0023] Figure 2 This is a schematic diagram showing the flow rate of the fluid inside an inorganic salt crystallization reactor.

[0024] Figure 3 This is a diagram showing the distribution of turbulent energy dissipation rate within an inorganic salt crystallization reactor.

[0025] Figure 4 This is a simulation diagram of the distribution of tracer in an inorganic salt crystallization reaction apparatus.

[0026] Figure 5 This is a schematic diagram showing the height of some components in an inorganic salt crystallization reaction apparatus according to an embodiment of this application.

[0027] Attached image annotations:

[0028] 100. Reaction vessel; 110. Feed inlet; 120. Discharge outlet; 130. First connecting port; 140. Reaction chamber; 210. First impeller; 220. Second impeller; 230. Stirring rod; 300. Overflow container; 310. Second connecting port; 320. Overflow outlet; 330. Settling chamber; 331. Settling wall; 400. Drive component. Detailed Implementation

[0029] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0030] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0031] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0032] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0033] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0034] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0035] Please see Figure 1 One embodiment of this application provides an inorganic salt crystallization reaction apparatus, including a reaction vessel 100, a stirring mechanism, and an overflow container 300. The reaction vessel 100 has a feed inlet 110, a discharge outlet 120, a first connecting port 130, and a reaction chamber 140 connected together. The stirring mechanism includes a stirring rod 230, a first blade 210, and a second blade 220. The stirring rod 230 is rotatably disposed in the reaction vessel 100. The first blade 210 and the second blade 220 are both connected to the stirring rod 230 and located in the reaction chamber 140. The first blade 210 and the second blade 220 are spaced apart along the axial direction of the stirring rod 230. The overflow container 300 has a second connecting port 310, an overflow port 320, and a precipitation chamber 330 connected together. The second connecting port 310 is connected to the first connecting port 130.

[0036] When using the aforementioned inorganic salt crystallization reaction apparatus, the raw materials are fed into the reaction chamber 140 through the feed port 110 of the reaction vessel 100. The stirring rod 230 inside the reaction chamber 140 rotates, driving the first impeller 210 and the second impeller 220 to stir the raw materials, thereby accelerating mixing and improving mixing uniformity. The mixed raw materials undergo a chemical reaction and ultimately generate inorganic salt crystals and mother liquor. The inorganic salt crystals precipitate at the bottom of the reaction vessel 100. Some of the inorganic salt crystals, driven by the mother liquor, sequentially enter the precipitation chamber 330 through the first connecting port 130 and the second connecting port 310. The mother liquor and inorganic salt crystals in the precipitation chamber 330 experience minimal disturbance; the inorganic salt crystals precipitate at the bottom of the precipitation chamber, while the mother liquor... The inorganic salt crystals will overflow from the overflow port 320 and flow back into the reaction chamber 140 after precipitation. The generated inorganic salt crystals will finally be discharged through the discharge port 120 to obtain the inorganic salt crystal product. Compared with the traditional technology, the above-mentioned inorganic salt crystallization reaction device uses the first blade 210 and the second blade 220 to fully mix the raw materials in the reaction chamber 140, which is conducive to the formation of inorganic salt crystals. The overflow container 300 enables the continuous reaction process and prevents unreacted materials from being discharged prematurely, which is conducive to the nucleation, crystal growth, and aging separation of inorganic salt nanoparticles, ensuring the particle size distribution and purity of inorganic salt crystals, thereby improving the crystallization efficiency of the inorganic salt crystallization reaction device and the quality of inorganic salt crystal products.

[0037] As an explanation, the inorganic salt crystallization reaction device in this embodiment can achieve continuous feeding and continuous discharging. The operator can continuously feed the raw materials into the reaction chamber 140 through the feed port 110. The stirring mechanism continuously stirs the raw materials, causing them to undergo a chemical reaction and generate inorganic salt crystals and mother liquor. The inorganic salt crystals settle at the bottom of the reaction container 100. Some of the inorganic salt crystals, driven by the mother liquor, sequentially enter the sedimentation chamber 330 through the first connecting port 130 and the second connecting port 310. When the raw materials continue to be fed into the feed port 110, the mother liquor in the sedimentation chamber 330 overflows from the overflow port 320 to achieve dynamic feeding and discharging, thereby realizing the continuous production of inorganic salt crystals. This is beneficial for the nucleation, crystal growth, and aging separation of inorganic salt nanoparticles, and improves production efficiency.

[0038] For further explanation, please refer to Figure 1 The height of the overflow port 320 should be lower than the maximum height of the reaction chamber 140. In this way, when the liquid level in the reaction chamber 140 is raised due to continuous feeding into the reaction chamber 140, and the liquid level is eventually higher than the height of the overflow port 320, according to the principle of communicating vessels, the mother liquor in the sedimentation chamber 330 will overflow from the overflow port 320, so that the inorganic salt crystallization reaction device can realize continuous feeding and continuous discharge.

[0039] Optionally, in some embodiments, the stirring rod 230 can be rotated by setting a driving component 400; in other embodiments, the stirring rod 230 can also be rotated by manual operation, which is not specifically limited here.

[0040] Please see Figure 1 The first blade 210 is provided with at least two blades, and one end of the at least two first blades 210 is arranged at intervals along the circumference of the stirring rod 230 on the side wall of the stirring rod 230. While improving the stirring efficiency, the at least two first blades 210 can share the force, thereby reducing the shaking of the stirring rod 230 and reducing equipment wear.

[0041] Furthermore, the first blade 210 is provided with an even number, for example, in Figure 1 In the embodiment shown, four first blades 210 are provided. In this way, while ensuring the stirring effect, the radial force of the stirring rod 230 can be balanced, vibration can be reduced, and energy consumption can be reduced.

[0042] Please see Figure 1 In one embodiment, at least two second blades 220 are also provided, similar to the first blade 210, which will not be described in detail here.

[0043] In one embodiment, the raw materials can be pretreated acidic etching waste liquid and alkaline solution. The pretreated acidic etching waste liquid and alkaline solution are continuously fed into the feed port 110 and a chemical reaction occurs in the reaction chamber 140 to achieve continuous production of inorganic salt crystals.

[0044] Furthermore, the inorganic salt crystallization reaction apparatus in this embodiment can be used in the process of synthesizing inorganic salts with specific nanocrystal structures, such as copper oxide and basic copper chloride.

[0045] Please see Figure 1 In one embodiment, the stirring rod 230 extends axially along the depth direction of the reaction chamber 140, the second blade 220 is arranged on the side of the first blade 210 facing the bottom wall of the reaction chamber 140, the discharge port 120 is opened on the bottom wall of the reaction vessel 100, and the feed port 110 is arranged on the side of the first blade 210 away from the second blade 220.

[0046] The stirring rod 230 extends axially along the depth direction of the reaction chamber 140 so that the first blade 210 and the second blade 220 can be spaced apart along the depth direction of the reaction chamber 140. When the stirring rod 230 rotates in the reaction chamber 140, the arrangement of the first blade 210 facilitates the mixing of the fluid near it along the axial direction of the stirring rod 230, while the second blade 220 near the bottom wall of the reaction chamber 140 can lift the reaction liquid located near the bottom wall of the reaction chamber 140 upward to prevent inorganic salt crystals from accumulating on the bottom wall of the reaction chamber 140 and blocking the discharge port 120.

[0047] In addition, the first blade 210 located near the feed inlet 110 can preferentially stir the raw materials entering the reaction chamber 140 from the feed inlet 110, thereby improving the overall stirring efficiency of the raw materials.

[0048] Further, please refer to Figure 1 One end of the stirring rod 230 is rotatably mounted on the top wall of the reaction chamber 140, and the other end of the stirring rod 230 extends toward the bottom wall of the reaction chamber 140. The second blade 220 is located at the end of the stirring rod 230 near the bottom wall, so that when it rotates, it drives the reaction liquid located near the bottom wall of the reaction chamber 140 to rise upward.

[0049] Furthermore, a bottom valve is provided at the discharge port 120, which is used to control the opening and closing of the discharge port 120.

[0050] Please see Figure 5 In one embodiment, the first communication port 130 is opened on the side wall of the reaction vessel 100, the distance between the first blade 210 and the bottom wall of the reaction chamber 140 is set as D1, the distance between the second blade 220 and the bottom wall of the reaction chamber 140 is set as D2, and the distance between the first communication port 130 and the bottom wall of the reaction chamber 140 is set as D3, where D2 < D3 < D1.

[0051] The first connecting port 130 is positioned between the first blade 210 and the second blade 220, so that the position of the first connecting port 130 is neither too close to the bottom wall of the reaction chamber 140 nor too close to the feed port 110 located on the side of the first blade 210 away from the second blade 220. This prevents inorganic salt crystals located near the bottom wall of the reaction chamber 140 from entering the overflow chamber through the first connecting port 130, and prevents raw materials fed into the reaction chamber 140 from flowing from the first connecting port 130 to the overflow chamber before they have fully reacted.

[0052] As an explanation, if the first connecting port 130 is arranged on the side of the first blade 210 away from the second blade 220 (i.e., D3 > D1), the raw material entering the reaction chamber 140 from the feed port 110 will flow directly from the first connecting port 130 into the sedimentation chamber 330, and cannot fully react in the reaction chamber 140, thus reducing the utilization rate of the raw material; if the first connecting port 130 is arranged on the side of the second blade 220 away from the first blade 210 (i.e., D3 < D2), the inorganic salt crystals precipitated near the discharge port 120 on the bottom wall of the reaction chamber 140 will easily flow from the first connecting port 130 into the sedimentation chamber 330, affecting the discharge efficiency; based on the above, it is preferable to set the position of the first connecting port 130 between the first blade 210 and the second blade 220, i.e., D2 < D3 < D1.

[0053] Furthermore, through experimental optimization, it was determined that the position of the first connecting port 130 should be located at 1 / 2 of the maximum liquid level height in the reaction chamber 140 (that is, the position between the first blade 210 and the second blade 220). This position can improve the reaction efficiency while ensuring the quality of inorganic salt crystals.

[0054] Please see Figure 1 In one embodiment, the height of the second connection port 310 is lower than the height of the overflow port 320.

[0055] Since the height of the overflow port 320 is higher than the height of the second connecting port 310, some inorganic salt crystals and mother liquor in the reaction chamber 140 enter the sedimentation chamber 330 through the second connecting port 310 and gradually rise in the sedimentation chamber 330. During the rising process, the inorganic salt crystals settle, while the mother liquor gradually rises to the overflow port 320 and overflows from the overflow port 320, so as to achieve continuous feeding and continuous discharge.

[0056] Please see Figure 1 In one embodiment, one side wall of the sedimentation chamber 330 is set as sedimentation wall 331, and the plane on which the sedimentation wall 331 is located is set at an angle to the ground.

[0057] When some inorganic salt crystals and mother liquor enter the precipitation chamber 330 through the second connecting port 310, the inorganic salt crystals gradually precipitate on the precipitation wall 331. Since the plane where the precipitation wall 331 is located is at an angle to the ground, the inorganic salt crystals precipitated on the precipitation wall 331 gradually move to a lower position under the action of gravity, and return to the reaction chamber 140 through the second connecting port 310 located at the lower position of the precipitation chamber 330. Finally, they gather near the bottom wall of the reaction chamber 140 and are discharged from the discharge port 120 opened on the bottom wall of the reaction chamber 140 together with the generated inorganic salt crystals.

[0058] Further, please refer to Figure 1 The relatively higher end of the precipitating wall 331 is connected to the overflow port 320, and the relatively lower end of the precipitating wall 331 is connected to the second connecting port 310. In this way, the inorganic salt crystals precipitated on the precipitating wall 331 can gradually move towards the second connecting port 310 under the action of gravity, and finally enter the reaction chamber 140 through the second connecting port 310 and precipitate at the bottom wall of the reaction chamber 140.

[0059] Please see Figure 1 In one embodiment, the angle between the plane containing the sedimentation wall 331 and the ground is set to α, where 45°≤α≤75°.

[0060] The angle α between the plane where the sedimentation wall 331 is located and the ground is set to 45°≤α≤75°, so that the mother liquor can form a stable flow pattern in the sedimentation chamber 330. Under this slope, the sedimentation wall 331 can not only ensure the sedimentation effect of inorganic salt crystals, but also prevent excessive inorganic salt crystals from precipitating on the sedimentation wall 331 and causing accumulation, thereby blocking the second communication port 310.

[0061] To explain, if α < 45°, the flow velocity of the mother liquor and inorganic salt crystals in the sedimentation chamber 330 is low. Although this is beneficial for the precipitation of inorganic salt crystals, it requires a larger horizontal projected area, thus increasing the volume of the device. In addition, it is easy for inorganic salt crystals to accumulate on the sedimentation wall 331, eventually causing blockage of the second connection port 310. If α < 75°, the flow velocity of the mother liquor and inorganic salt crystals in the sedimentation chamber 330 is high, which is not conducive to the precipitation of inorganic salt crystals. In summary, considering the separation effect of inorganic salt crystals, space utilization, and anti-accumulation factors, setting α to 45° ≤ α ≤ 75° can ensure a good separation effect of inorganic salt crystals while avoiding material accumulation and having a compact structure.

[0062] Preferably, α is 60°.

[0063] To further explain, the purpose of setting up the overflow container 300 is to actively create a low-turbulence zone, requiring relatively stable fluid velocity and direction, avoiding pulsating flow, and ensuring that the low turbulence intensity and low energy dissipation rate mean that the turbulent shear force in this zone is insufficient to destroy the specific nanocrystal structures already formed within the fluid. This container allows for a continuous reaction process, thereby facilitating the nucleation, crystal growth, and aging separation of inorganic salt nanoparticles.

[0064] The ratio of the volume of the sedimentation chamber 330 to the volume of the reaction chamber 140 has a significant impact on the overflow effect. When the volume of the sedimentation chamber is too small, inorganic salt crystals cannot be effectively separated, resulting in uneven particle size distribution. When the volume of the overflow chamber is too large, it increases the overall complexity and cost of the device. Through analysis of different ratios, it was determined that the optimal ratio is 1 / 5 of the volume of the sedimentation chamber 330 to the volume of the reaction chamber 140.

[0065] Please see Figure 1 In one embodiment, the plane containing the first blade 210 is set at an angle to the ground, and the plane containing the second blade 220 is set at an angle to the ground.

[0066] Since the plane of the first blade 210 is at an angle to the ground, when the stirring rod 230 rotates, the fluid around the first blade 210 (such as raw materials, mother liquor, etc.) can move along the axial direction of the stirring rod 230 under the action of the inclined first blade 210 to achieve full mixing. The second blade 220 is similar to the first blade 210. The second blade 220 can drive the fluid near the bottom wall of the reaction chamber 140 to move along the axial direction of the stirring rod 230 to prevent inorganic salt crystals from precipitating at the bottom wall of the reaction chamber 140 and blocking the discharge port 120.

[0067] For example, in Figure 1 In the embodiment shown, the plane containing the first blade 210 and the plane containing the second blade 220 are both set at an angle to the ground. From a top-down perspective, the stirring rod 230 rotates counterclockwise to drive the fluid to flow upward.

[0068] Please see Figure 1 In one embodiment, the angle between the plane where the first blade 210 is located and the ground is set to β, and the angle between the plane where the second blade 220 is located and the ground is set to γ, where β > γ.

[0069] According to the simulation results, when the angle β between the plane of the upper first blade 210 and the ground is greater than the angle γ between the plane of the lower second blade 220 and the ground, an ideal circulating flow field can be formed in the reaction chamber 140, so that the raw materials in each region of the reaction chamber 140 can be effectively mixed, thereby improving the mixing efficiency and the inorganic salt crystallization efficiency.

[0070] Furthermore, in one embodiment, β is 45° and γ is 30°.

[0071] Please see Figure 1 In one embodiment, at least two first blades 210 are provided, and the at least two first blades 210 are spaced apart along the axial direction of the stirring rod 230.

[0072] By setting at least two first blades 210 spaced apart along the axial direction of the stirring rod 230, dead zones in the reaction chamber 140 can be effectively eliminated, allowing the raw materials in the reaction chamber 140 to be mixed evenly and improving the mixing efficiency of the raw materials in the reaction chamber 140.

[0073] As an explanation, in some embodiments, if the height of the reaction chamber 140 is relatively high, it is not possible to ensure the uniformity of mixing of the raw materials in the reaction chamber 140 by only setting one first blade 210. In this case, by setting multiple first blades 210 spaced apart along the axial direction of the stirring rod 230, the raw materials at different depths in the reaction chamber 140 can be fully mixed, thereby ensuring the inorganic salt crystallization effect.

[0074] Please see Figure 1 In one embodiment, the reaction vessel 100 includes a vessel body and a top cover. The vessel body has a reaction chamber 140, the top cover is assembled with the vessel body, and the feed inlet 110 is opened on the top cover.

[0075] The feed inlet 110 is located on the top cover of the reaction vessel 100 to facilitate feeding operations and mixing of raw materials.

[0076] Please see Figure 1 In one embodiment, the stirring mechanism further includes a drive member 400, which is disposed on the top cover and located outside the reaction chamber 140, and the stirring rod 230 passes through the top cover and is drivenly connected to the drive member 400.

[0077] Placing the drive unit 400 outside the reaction chamber 140 can prevent the fluid inside the reaction chamber 140 from soaking the drive unit 400 and causing damage to the drive unit 400. The stirring rod 230 passes through the top wall of the reaction vessel 100 and is drivenly connected to the drive unit 400. The drive unit 400 can provide rotational power to the stirring rod 230 to drive the first blade 210 and the second blade 220 to fully mix the raw materials in the reaction chamber 140.

[0078] Furthermore, the driving component 400 is a drive motor, and the stirring rod 230 is located at the output end of the drive motor so that the stirring rod 230 has a rotation function.

[0079] The structural parameters of the first blade 210 and the second blade 220 have a significant impact on the stirring effect. Through comparison and optimization of various blade configurations, the following structural parameters were determined:

[0080] First blade 210: It adopts a 45° inclined (i.e. β=45°) propulsion blade with a diameter of 1 / 2 of the cross-sectional radius of the reaction chamber 140 and a blade width of 1 / 5 of the blade diameter. This design is conducive to pushing the fluid in the middle upward and promoting the axial mixing of raw materials.

[0081] The second blade 220 is a propulsion blade with a 30° inclination (i.e., γ = 30°). Its diameter is 1 / 1.7 of the cross-sectional radius of the reaction chamber 140, and its blade width is 1 / 6 of the blade diameter. Its main function is to lift the fluid at the bottom of the reaction chamber 140 upward to prevent inorganic salt crystals from precipitating and accumulating and clogging the discharge port 120.

[0082] Furthermore, the distance between the first blade 210 and the second blade 220 is half the cross-sectional radius of the reaction chamber 140. This distance ensures that the flow fields generated by the first blade 210 and the second blade 220 interact and form a good overall circulation.

[0083] Please see Figures 2 to 4Using commercially available finite volume simulation software, the fluid dynamics characteristics within the reaction chamber 140 are comprehensively understood by analyzing parameters such as the velocity distribution, energy dissipation rate distribution, and tracer concentration distribution of the fluid within the reaction chamber 140, providing a scientific basis for the optimization of the inorganic salt crystallization reaction device.

[0084] Please see Figure 2 , Figure 2 In the diagram, (a), (c), and (e) are the fluid velocity streamline diagram, fluid velocity distribution cloud diagram, and fluid velocity vector distribution diagram, respectively, when only one layer of blades is installed (hereinafter referred to as the R1 configuration). Figure 2 Figures (b), (d), and (f) show the fluid velocity streamline diagram, fluid velocity distribution cloud diagram, and fluid velocity vector distribution diagram, respectively, when two layers of blades (i.e., the first blade 210 and the second blade 220, hereinafter referred to as the R2 configuration) are configured in this application. Figure 2 The simulation results show that, compared with the R1 configuration, the advantages of the R2 configuration in this application are reflected in the following three aspects:

[0085] (1) The fluid in the reaction chamber 140 with two layers of blades has a more uniform velocity distribution and no obvious stagnation zone.

[0086] (2) The fluid velocity in the reaction chamber 140 with two layers of blades is relatively high, which is more conducive to raw material mixing and solid particle dispersion.

[0087] (3) The reaction chamber 140 with two layers of blades has two interacting double circulation flow lines, which helps to extend the residence time of the raw materials in the reaction chamber 140 (i.e., the number of cycles), reduce the occurrence of short circuits, and is more conducive to the reaction or crystal growth.

[0088] Figure 3 The figures show the turbulent energy dissipation rate distribution within reaction chamber 140 obtained from CFD simulations. Figures a and c represent the turbulent energy dissipation rate distribution under the R1 configuration, while figures b and d represent the turbulent energy dissipation rate distribution under the R2 configuration. Analysis of the energy dissipation rate distribution reveals the turbulent characteristics of different regions within reaction chamber 140. Simulation results show that the energy dissipation rate is highest near the blades and gradually decreases with distance from the blades. Overall, the average energy dissipation rate within reaction chamber 140 under the R2 configuration is 15.8 m² / s³, with high-energy-dissipation regions (energy dissipation rate > 10 m² / s³) accounting for 35%. This provides sufficient microscopic mixing energy for the reaction, which is beneficial for generating small and uniformly distributed nanocrystalline particles.

[0089] To explain the adverse phenomena such as fluid short-circuiting and stagnation within the reaction chamber 140 of the R1 and R2 configurations, please refer to [link to relevant documentation]. Figure 4 , Figure 4To simulate the tracer distribution, a tracer pulse injection method was used to simulate the residence time distribution of the material in the reactor. Among them, (a), (c) and (e) show the tracer concentration distribution at t=5s, t=7.5s and t=10s in the R1 configuration, respectively, and (b), (d) and (f) show the tracer concentration distribution at t=5s, t=7.5s and t=10s in the R2 configuration, respectively.

[0090] Depend on Figure 4 The results show that in the initial feeding stage (t=5s), within the R1 configuration reaction chamber 140, the material is rapidly transported to the bottom region of the reaction chamber 140 under the action of the impeller; in the upper part of the reaction chamber 140, the tracer mass fraction is zero. Figure 4 In (a), the material was not evenly dispersed, which is consistent with the flow field distribution results. Figure 4 [a], [c], and [e] in the R2 configuration reaction chamber 140. The tracer is concentrated above the reaction chamber 140, and the dispersion area almost fills the entire upper region of the reaction chamber 140. Figure 4 (b) indicates that the material is relatively evenly dispersed in the initial stage of feeding, which further confirms the flow field distribution results. Figure 4 [b), (d), and (f)]. When t = 7.5 s, the tracer dispersion area in the reaction chamber 140 of the R1 configuration significantly increased, but there were still some areas in the upper part of the reaction chamber 140 without tracer distribution, especially in the precipitation chamber 330 where tracer was already present. Figure 4 [c] indicates the occurrence of a short circuit; while in the R2 configuration, the tracer distribution in the reaction chamber 140 gradually diffuses towards the bottom of the reaction chamber 140, with significant tracer distribution in the upper and middle regions of the reaction chamber 140, and the tracer concentration in the precipitation chamber 330 is zero. Figure 4 [d] indicates that the R2 configuration reaction chamber 140 has a more uniform material distribution and fewer fluid short-circuit events. At t=10s, the tracer almost fills the entire reaction chamber 140, but it can be noted that there is no significant tracer concentration distribution in the upper part of the R1 configuration reaction chamber 140 and the lower region of the R2 configuration reaction chamber 140, suggesting possible fluid stagnation in these areas. In summary, compared to the R1 configuration, the R2 configuration reaction chamber 140 has a more uniform dispersion effect and fewer fluid short-circuit events, but both have stagnation areas.

[0091] The optimized R2 configuration of the reaction chamber 140 significantly improves fluid velocity distribution uniformity, energy dissipation rate distribution, and residence time distribution. Simulation results show that when the tilt angle β of the first blade 210 is 45° and the tilt angle γ of the second blade 220 is 30°, an ideal overall circulating flow field is formed within the reaction chamber 140, enabling effective mixing of the fluid in the upper, middle, and lower regions.

[0092] By optimizing the design of the stirring mechanism, the mixing efficiency and energy utilization efficiency within the reaction chamber 140 were improved, providing favorable hydrodynamic conditions for the synthesis of inorganic salts with specific nanocrystalline structures. This not only improved the reaction rate and conversion rate but also helped control the particle size distribution and morphology of the products.

[0093] In a preferred embodiment of this application, the reaction chamber 140 has a volume of 5000L, the reaction temperature is controlled at 75℃, the pH value at 10.0, the stirring rod 230 rotates at 60rpm, the residence time is 50min, and pretreated acidic etching waste liquid and alkaline solution are continuously added. The stirring mode is characterized by "the first blade 210 and the second blade 220 tilting in the same direction, rotating counterclockwise, and simultaneously pushing the flow upwards," and the test is conducted continuously for 240h. Analysis of the synthesized inorganic salt crystals and the production process shows that the average particle size of the inorganic salt crystals is 49μm, the separation rate of 50μm particles is 98.8%, and the bottom valve blockage rate is <10%.

[0094] Furthermore, the overflow hopper had a volume of 1000L, and the experiment was conducted continuously for 240 hours. Analysis of the synthesized inorganic salt crystals, the separation effect of the inorganic salt crystals, and the particle size of the inorganic salt crystals revealed that the particle separation efficiency (50μm) was 96%, the particle separation efficiency (<50μm) was 80%, and the average particle size of the product was 50μm.

[0095] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0096] The above embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An inorganic salt crystallization reaction apparatus, characterized in that, include: A reaction vessel having a feed inlet, a discharge outlet, a first connecting outlet, and a reaction chamber connected in series; A stirring mechanism, comprising a stirring rod, a first impeller, and a second impeller, wherein the stirring rod is rotatably mounted on the reaction vessel, and both the first and second impellers are connected to the stirring rod and located within the reaction chamber, the first and second impellers being spaced apart along the axial direction of the stirring rod; and An overflow container having a second connecting port, an overflow port, and a sedimentation chamber connected together, wherein the second connecting port is connected to the first connecting port.

2. The inorganic salt crystallization reaction apparatus according to claim 1, characterized in that, The stirring rod extends axially along the depth direction of the reaction chamber, the second blade is arranged on the side of the first blade facing the bottom wall of the reaction chamber, the discharge port is opened on the bottom wall of the reaction vessel, and the feed port is arranged on the side of the first blade away from the second blade.

3. The inorganic salt crystallization reaction apparatus according to claim 2, characterized in that, The first communication port is opened on the side wall of the reaction vessel. The distance between the first blade and the bottom wall of the reaction chamber is set as D1, the distance between the second blade and the bottom wall of the reaction chamber is set as D2, and the distance between the first communication port and the bottom wall of the reaction chamber is set as D3, where D2 < D3 < D1.

4. The inorganic salt crystallization reaction apparatus according to claim 1, characterized in that, The height of the second connecting port is lower than the height of the overflow port.

5. The inorganic salt crystallization reaction apparatus according to claim 1, characterized in that, One side wall of the sedimentation chamber is designated as the sedimentation wall, and the plane containing the sedimentation wall is set at an angle to the ground.

6. The inorganic salt crystallization reaction apparatus according to claim 5, characterized in that, The angle between the plane containing the sedimentation wall and the ground is set as α, where 45°≤α≤75°.

7. The inorganic salt crystallization reaction apparatus according to claim 1, characterized in that, The plane containing the first blade is set at an angle to the ground, and the plane containing the second blade is set at an angle to the ground.

8. The inorganic salt crystallization reaction apparatus according to claim 7, characterized in that, Let β be the angle between the plane containing the first blade and the ground, and let γ be the angle between the plane containing the second blade and the ground, where β > γ.

9. The inorganic salt crystallization reaction apparatus according to claim 1, characterized in that, The reaction vessel includes a container body and a top cover. The container body has the reaction chamber, the top cover is assembled with the container body, and the feed inlet is located on the top cover.

10. The inorganic salt crystallization reaction apparatus according to claim 9, characterized in that, The stirring mechanism also includes a driving component, which is disposed on the top cover and located outside the reaction chamber. The stirring rod passes through the top cover and is drivenly connected to the driving component.

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