A high-purity instant potassium sulfate screening device and method

Abstract

The application relates to the technical field of chemical raw material production, in particular to a high-purity instant potassium sulfate screening device and method, which comprises a first screen cylinder, a second screen cylinder and a material guiding assembly, the rotating directions of the first screen cylinder and the second screen cylinder are opposite, the two ends of the first screen cylinder are through-penetrated, the material guiding assembly is inserted into the first screen cylinder and located above the second screen cylinder, the bottom of the second screen cylinder and the inner cavity bottom of the first screen cylinder are reserved with extrusion spaces for crushing potassium sulfate agglomerates, the inner cavity of the second screen cylinder is provided with an impurity containing cavity, and the side wall of the second screen cylinder is provided with elastic turning plates which are extruded open. The application can perform three crushing procedures on material agglomerates, improves the crushing efficiency, ensures the uniform particle size distribution of the material, the second screen cylinder can collect impurities, and when crushing the agglomerates between the two screen cylinders, the extrusion of hard impurities cannot cause the situation of being stuck, the protruding pieces can continuously dredge the first screen holes in this process, and the process of stopping and cleaning is avoided.

Description

Technical Field

[0001] This invention relates to the field of chemical raw material production technology, and in particular to a high-purity, fast-dissolving potassium sulfate screening device and method. Background Technology

[0002] Potassium sulfate, as a high-quality chlorine-free potassium fertilizer and an important chemical raw material, is widely used in the cultivation of chlorine-sensitive economic crops (such as tobacco, fruits, and vegetables) and in industries such as medicine and glass. For fast-dissolving potassium sulfate, its core value lies in its rapid and complete dissolution in water, facilitating modern precision irrigation and foliar spraying. Achieving excellent solubility requires not only high chemical purity but, more importantly, an ideal physical morphology: uniform crystal particle size, no agglomeration, no excessively large particles, and powder with good flowability and high specific surface area. Sieving, as a core physical separation process for controlling the final particle size distribution and removing oversized particles and agglomerates, is crucial for ensuring the quality of fast-dissolving potassium sulfate.

[0003] In existing instant potassium sulfate production processes, screening is required first. This serves two purposes: first, to ensure uniform particle size distribution of the potassium sulfate, guaranteeing dissolution efficiency; and second, to remove impurities such as stones, ensuring high product purity. Potassium sulfate crystals easily form tiny lumps or soft agglomerates during production, drying, and transportation. Traditional screening equipment is insufficient to break up these micro-lumps caused by electrostatic forces, surface tension, or residual moisture. Since the size of potassium sulfate crystal lumps is larger than that of impurities, and vice versa, in practice, sieves designed only for potassium sulfate crystals result in material loss due to lumps and low screening efficiency. Including crushing components within the screening device can easily cause hard impurities such as stones to jam the crushing components. Furthermore, high-purity potassium sulfate crystals are easily clogged by fine powder or micro-lumps when passing through sieves, especially with materials having slightly higher moisture content or strong electrostatic adsorption. Frequent downtime for manual cleaning or screen replacement not only significantly reduces production efficiency but also increases labor costs and downtime losses. Summary of the Invention

[0004] To solve the above-mentioned technical problems, the present invention provides a high-purity, fast-dissolving potassium sulfate screening device and method.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A high-purity, fast-dissolving potassium sulfate sieving device includes a first sieve cylinder for sieving potassium sulfate crystal particles and a feeding assembly. The first sieve cylinder is open at both ends, and the feeding tube of the feeding assembly extends into the upper end of the inner cavity of the first sieve cylinder. A second sieve cylinder is also provided inside the first sieve cylinder in the opposite direction of rotation to the first sieve cylinder. The second sieve cylinder is located below the feeding tube. The bottom of the second sieve cylinder and the bottom of the inner cavity of the first sieve cylinder are reserved with a compression space for breaking up potassium sulfate clumps. The inner cavity of the second sieve cylinder is provided with an impurity receiving cavity, and the side wall of the second sieve cylinder is provided with an elastic flap that can be opened by compression.

[0007] Furthermore, a mounting frame is fixedly installed at one end of the first screen cylinder. A rotating shaft driven by an external power source is mounted on the mounting frame. The end of the rotating shaft facing the inner cavity of the first screen cylinder is connected to the second screen cylinder via a transmission assembly. The mounting frame has a cross-shaped structure, and the rotating shaft passes through the center of the mounting frame and is fixedly connected to it. When the external power source drives the rotating shaft, the rotating shaft drives the entire first screen cylinder to rotate, realizing the process of rotating and screening materials. The transmission assembly allows a single power source to drive the first and second screen cylinders to rotate synchronously in opposite directions, reducing additional power consumption.

[0008] Furthermore, it also includes a first support frame for supporting the first screen cylinder. The first support frame is provided with a positioning hole for the rotating shaft to pass through, and the first support frame is fixedly installed on the support base. The first support frame is used to support the erection of the first screen cylinder. Two limiting components are provided on the rotating shaft, which are located at the front end and rear end of the shaft passing through the first support frame, respectively, to ensure that no lateral displacement or tilting occurs during the rotation of the rotating shaft.

[0009] Furthermore, a rotating wheel is provided at the end of the rotating shaft away from the first screen cylinder, and a drive motor is provided on the support base. The rotating wheel is connected to the drive motor via a rotating belt. The operation of the drive motor drives the rotating belt to rotate, which in turn drives the rotating wheel to rotate synchronously. The rotation of the rotating wheel then drives the first screen cylinder to rotate via the rotating shaft. At the same time, through mutually cooperating transmission components, the second screen cylinder is driven to rotate in the opposite direction, realizing the functions of screening, breaking up agglomerates, and collecting impurities.

[0010] Furthermore, the transmission assembly includes a positioning plate, a synchronous pulley, a first transmission pulley, a second transmission pulley, and a driven shaft. The rotating shaft passes through the positioning plate and connects to the synchronous pulley. The driven shaft is located below the synchronous pulley. The first and second transmission pulleys are located on opposite sides of the synchronous pulley. The driven shaft, the first transmission pulley, and the second transmission pulley are connected by a transmission belt. The driven shaft, the first transmission pulley, and the second transmission pulley are all located on the inner side of the transmission belt, and the synchronous pulley is located on the outer side of the transmission belt. The rotating shaft is fixedly connected to the shaft core of the synchronous pulley. When the drive motor is working, the rotating shaft rotates, causing the synchronous pulley to rotate accordingly. The synchronous pulley and the driven shaft are aligned vertically. The first and second transmission pulleys are located on opposite sides of the synchronous pulley. The driven shaft is connected to the first and second transmission pulleys by a transmission belt. The rotation direction of the driven shaft is the same as the rotation direction of the first and second transmission pulleys. Since the synchronous pulley is located on the outer side of the transmission belt, its rotation direction is opposite to that of the driven shaft.

[0011] Furthermore, the sidewall of the second sieve cylinder is provided with several strip-shaped grooves that penetrate the inner cavity at equal intervals. The long side of the strip-shaped grooves is parallel to the axis of the second sieve cylinder. The elastic flaps are rotated and cover the strip-shaped grooves by a torsion spring. The width and diameter of the strip-shaped grooves are larger than the size of conventional impurity particles. In the compression space, the relative rotation of the first and second sieve cylinders can crush and decompose the agglomerated potassium sulfate particles. The decomposed and qualified particles fall out from the first sieve hole, while larger impurities, unable to pass through the first sieve hole of the first sieve cylinder, will be pushed by the relative compression of the first and second sieve cylinders to flip the adjacent elastic flaps into the inner cavity of the second sieve cylinder. At this time, the impurities will be pushed into the inner cavity of the second sieve cylinder. After losing the compression force, the elastic flaps will restore their elastic deformation and continue to close the strip-shaped grooves.

[0012] Furthermore, the elastic flap is provided with several compressible and expandable protrusions. Several first screen holes are evenly distributed on the first screen cylinder. The distribution spacing of the protrusions corresponds to the distribution spacing of the first screen holes, and the cross-sectional dimensions of the protrusions are adapted to the dimensions of the first screen holes. In the compression space, when a protrusion encounters a hard impurity, its internal elastic component compresses it, preventing jamming during rotation. The size of the protrusions is slightly larger than the size of the first screen holes. Located directly below the second screen cylinder, the bottom of the second screen cylinder is tangent to the bottom of the inner cavity of the first screen cylinder. At the tangent point, several horizontally arranged protrusions fit precisely into the first screen holes of the same row on the first screen cylinder, allowing for periodic unblocking of clogged first screen holes.

[0013] Furthermore, several second sieve holes of the same size as the first sieve holes are provided between any two of the strip grooves, and these second sieve holes are equally spaced along the long axis of the second sieve cylinder. Since the aperture of the second sieve holes is larger than the size of the crystal particles but smaller than the size of the impurities, the second sieve holes can allow any crystal particles that accidentally enter the second sieve cylinder and meet the requirements to fall out or be thrown out by centrifugal force, while retaining the impurities in the second sieve cylinder.

[0014] Furthermore, the material guiding assembly includes a material guiding unit and a material guiding pipe. The bottom end of the material guiding pipe has an opening, the length of which is the same as the length of the second screen cylinder. The material guiding unit draws the material into the material guiding pipe, and the slit-like opening forces the material to form a thin, evenly distributed layer above the second screen cylinder, ensuring uniform material distribution and crushing, and reducing the reduction in screening efficiency caused by uneven distribution.

[0015] Furthermore, annular surrounding plates are provided at both ends of the first screen cylinder. During the rotation of the first screen cylinder, the annular surrounding plates ensure that the material will not fall out from both sides of the first screen cylinder, thus ensuring the normal screening process of the material.

[0016] Furthermore, the support base is provided with a material collection trough notch, which is located directly below the first screen cylinder. A material collection device is installed below the material collection trough notch to collect potassium sulfate crystal particles that meet the requirements. Simultaneously, after one operating cycle, the second screen cylinder is removed and impurities are cleaned to ensure the normal operation of subsequent screening processes.

[0017] Furthermore, a second support frame is also provided on the support base, and the second support frame is connected to one end of the second screen cylinder via a rotating shaft. The second support frame and the first support frame are arranged opposite to the first screen cylinder. Since a mounting bracket is provided at the end of the first screen cylinder facing the first support frame, and the mounting bracket rotates with the rotation of the first screen cylinder, the second support frame is set at the other end of the first screen cylinder to ensure the normal installation of the second screen cylinder.

[0018] A method for using a high-purity, rapidly soluble potassium sulfate sieving device, characterized by comprising the following steps:

[0019] S1: Feeding and initial crushing: Start the drive motor and drive the rotating shaft to rotate through the rotating belt. This causes the first screen cylinder to rotate in the forward direction while the second screen cylinder rotates in the reverse direction. The potassium sulfate material to be screened is introduced into the first screen cylinder through the feed pipe. Under the action of gravity, the material impacts the side wall of the second screen cylinder, achieving the initial crushing of agglomerates.

[0020] S2: Impurity separation and secondary crushing of agglomerates. Qualified crystal particles and crushed small particles are screened out through the first screen cylinder and collected at the gap of the collection trough. Uncrushed agglomerates move with the material to the extrusion space and are crushed by the shear force generated by the inner wall of the first screen cylinder and the outer wall of the second screen cylinder. Hard impurities cannot be crushed and are forced into the impurity containment cavity.

[0021] S3: Fine screening and dynamic unblocking. The protrusions further impact and break up the remaining micro-clumps. At the same time, if the protrusions collide with hard impurities in the compression space, they will elastically contract to avoid being squeezed and stuck.

[0022] S4: When the protrusion rotates with the second screen cylinder, it periodically inserts into the first screen hole, forcibly pushing out the blockage and achieving continuous self-cleaning. The qualified potassium sulfate crystals after screening are output through the collection trough notch, and the impurities are collected in the second screen cylinder. Continuous feeding can achieve efficient screening and crushing cycle operation.

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

[0024] 1. The present invention provides a second screen cylinder inside a first screen cylinder, with the first and second screen cylinders rotating in opposite directions. This causes the agglomerated particles to be initially broken by gravity impact when they fall from the feed pipe into the second screen cylinder. The particles are then further broken by shear force in the compression space below the second screen cylinder. When the second screen cylinder rotates, the protrusions can further break the particles a third time, thus achieving the effect of efficient particle breaking.

[0025] 2. The present invention provides an impurity receiving cavity and an elastic flap inside the second screen cylinder. Hard impurities such as stones are locked in the impurity receiving cavity after entering through the elastic flap. At the same time, the movable elastic flap can prevent hard impurities from getting stuck in the compression space.

[0026] 3. By setting up protrusions and their matching structure with the first screen hole, and under the reverse rotation mechanism of the first screen cylinder and the second screen cylinder, the present invention achieves the effect of dynamically unblocking the first screen hole. For the first screen hole, which is very easy to cause blockage, the steps of frequent machine stoppage for manual cleaning or screen replacement can be reduced, which can greatly improve production efficiency and reduce labor costs and downtime losses. Attached Figure Description

[0027] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0028] Figure 2 This is a schematic diagram of the planar perspective structure of the present invention;

[0029] Figure 3 This is a schematic diagram of the disassembled structure of the second sieve cylinder;

[0030] Figure 4This is an exploded view of the rotating shaft and transmission components;

[0031] Figure 5 This is a schematic diagram of the transmission assembly.

[0032] Attached diagram labels: 1-First screen cylinder, 2-Second screen cylinder, 3-Guide pipe, 4-Elastic flap, 5-Mounting frame, 6-Rotating shaft, 7-First support frame, 8-Positioning hole, 9-Support base, 10-Rotating wheel, 11-Drive motor, 12-Rotating belt, 13-Positioning plate, 14-Synchronous wheel, 15-First transmission wheel, 16-Second transmission wheel, 17-Driven shaft, 18-Transmission belt, 19-Protrusion, 20-First screen hole, 21-Second screen hole, 22-Annular surrounding plate, 23-Collection trough notch, 24-Second support frame. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0034] Example 1, as Figures 1-5 As shown, the present invention discloses a high-purity, fast-dissolving potassium sulfate screening device, comprising a first screen cylinder 1 for screening potassium sulfate crystal particles and a material guiding assembly. The two ends of the first screen cylinder 1 are open, and the material guiding pipe 3 of the material guiding assembly extends into the upper end of the inner cavity of the first screen cylinder 1. A second screen cylinder 2 is also provided inside the first screen cylinder 1 in the opposite direction of rotation to the first screen cylinder 1. The second screen cylinder 2 is located below the material guiding pipe 3. The bottom of the second screen cylinder 2 and the bottom of the inner cavity of the first screen cylinder 1 are reserved with a compression space for breaking up potassium sulfate clumps. The inner cavity of the second screen cylinder 2 is provided with an impurity receiving cavity, and the side wall of the second screen cylinder 2 is provided with an elastic flap 4 that is squeezed open.

[0035] A mounting frame 5 is fixedly installed at one end of the first screen cylinder 1. A rotating shaft 6, driven by an external power source, is mounted on the mounting frame 5. The end of the rotating shaft 6 facing the inner cavity of the first screen cylinder 1 is connected to the second screen cylinder 2 via a transmission assembly. Specifically, the mounting frame 5 has a cross-shaped structure, and the rotating shaft 6 passes through the center of the mounting frame 5 and is fixedly connected to it. When the external power source drives the rotating shaft 6, the rotating shaft 6 drives the entire first screen cylinder 1 to rotate, realizing the process of rotating and screening materials. The transmission assembly allows for the synchronous reverse rotation of the first screen cylinder 1 and the second screen cylinder 2 driven by a single power source, reducing additional power consumption and avoiding spatial interference issues.

[0036] It also includes a first support frame 7 for supporting the first screen cylinder 1. The first support frame 7 is provided with a positioning hole 8 for the rotating shaft 6 to pass through. The first support frame 7 is fixedly installed on the support base 9. Specifically, the first support frame 7 is used to support the erection of the first screen cylinder 1. Two limiting components are provided on the rotating shaft 6. The two limiting components are located at the front end and the rear end of the first support frame 7, respectively, to ensure that no lateral displacement or tilting occurs during the rotation of the rotating shaft 6.

[0037] A rotating wheel 10 is provided at the end of the rotating shaft 6 away from the first screen cylinder 1. A drive motor 11 is provided on the support base 9. The rotating wheel 10 is connected to the drive motor 11 via a rotating belt 12. Specifically, the operation of the drive motor 11 drives the rotation of the rotating belt 12, which in turn drives the rotating wheel 10 to rotate synchronously. The rotation of the rotating wheel 10 then drives the rotation of the first screen cylinder 1 via the rotating shaft 6. At the same time, through the mutually cooperating transmission components, the second screen cylinder 2 is driven to rotate in the opposite direction, realizing the functions of screening, breaking up agglomerates, and collecting impurities. Preferably, a self-aligning roller bearing is embedded in the positioning hole 8 of the first support frame 7, so that the rotating shaft 6 only transmits torque, and the radial load is borne by the bearing. At the rotating shaft connection of the second support frame 24, a seated spherical bearing is used to form a second support point, so that the rotating shaft 6 only bears torsional load and eliminates bending stress. A bearing seat can be added to the rotating shaft 6 to bear radial and axial loads. This reduces the load on the rotating shaft 6 and ensures long-term stable operation.

[0038] The transmission assembly includes a positioning plate 13, a synchronous pulley 14, a first transmission pulley 15, a second transmission pulley 16, and a driven shaft 17. The rotating shaft 6 passes through the positioning plate 13 and is connected to the synchronous pulley 14. The driven shaft 17 is located below the synchronous pulley 14. The first transmission pulley 15 and the second transmission pulley 16 are located on both sides of the synchronous pulley 14, respectively. The driven shaft 17, the first transmission pulley 15, and the second transmission pulley 16 are connected by a transmission belt 18. The driven shaft 17, the first transmission pulley 15, and the second transmission pulley 16 are all located on the inner side of the transmission belt 18, and the synchronous pulley 14 is located on the outer side of the transmission belt 18. Specifically, the rotating shaft 6 is fixedly connected to the shaft core of the synchronous pulley 14. When the drive motor 11 is working, the rotating shaft 6 rotates, causing the synchronous pulley 14 to rotate accordingly. The synchronous pulley 14 and the driven shaft 17 are aligned vertically. The first transmission pulley 15 and the second transmission pulley 16 are respectively disposed on both sides of the synchronous pulley 14. The driven shaft 17 is connected to the first transmission pulley 15 and the second transmission pulley 16 via a transmission belt 18. The rotation direction of the driven shaft 17 is the same as the rotation direction of the first transmission pulley 15 and the second transmission pulley 16. Since the synchronous pulley 14 is disposed on the outside of the transmission belt 18, the rotation direction of the synchronous pulley 14 is opposite to the rotation direction of the driven shaft 17. In summary, when the drive motor 11 is working, the synchronous pulley 14 rotates in the same direction as the output shaft of the electric drive motor 11, while the driven shaft 17 rotates in the opposite direction to the output shaft of the drive motor 11. Preferably, the positioning plate 13 is provided with circular holes for the synchronous pulley 14, the first transmission pulley 15, the second transmission pulley 16, and the driven shaft 17 to pass through. The first transmission pulley 15, the second transmission pulley 16, and the driven shaft 17 are rotatably mounted on the positioning plate 13. Since the synchronous pulley 14 is fixed by the rotating shaft 6 and will not move, and the driven shaft 17 is fixedly connected to one end of the second screen cylinder 2, the relative position of the driven shaft 17 is fixed by the second screen cylinder 2, so that the driven shaft 17 will not move either. Even if the positioning plate 13 is not fixed by any object, its upper and lower circular holes are positionally limited, thus ensuring the relative fixation and stability of its position. The positioning plate 13 is used to fix the relative position of the first transmission pulley 15 and the second transmission pulley 16, so that the transmission belt 18 can stably drive the stable rotation of each pulley.

[0039] The second sieve cylinder 2 has several strip-shaped grooves evenly spaced on its side wall, each groove penetrating the inner cavity. The long side of each groove is parallel to the axis of the second sieve cylinder 2. The elastic flap 4 rotates and covers the grooves via a torsion spring. Specifically, the width of the grooves is larger than the size of conventional impurity particles (such as stones or particulate impurities). In the compression space, the relative rotation of the first sieve cylinder 1 and the second sieve cylinder 2 can crush and decompose the agglomerated potassium sulfate particles. The decomposed, compliant particles fall out through the first sieve hole 20. However, larger impurities, unable to pass through the first sieve hole 20 of the first sieve cylinder 1, are pushed by the relative compression of the first sieve cylinder 1 and the second sieve cylinder 2, causing the adjacent elastic flap 4 to flip into the inner cavity of the second sieve cylinder 2. At this time, the impurities are pushed into the inner cavity of the second sieve cylinder 2. After losing the compression force, the elastic flap 4 returns to its elastic deformation and continues to close the grooves.

[0040] The elastic flap 4 is provided with several compressible and expandable protrusions 19. The first sieve cylinder 1 has several evenly distributed first sieve holes 20. The distribution spacing of the protrusions 19 corresponds to the distribution spacing of the first sieve holes 20, and the cross-sectional dimensions of the protrusions 19 are adapted to the dimensions of the first sieve holes 20. Specifically, in the compression space, when the protrusions 19 come into contact with hard impurities, their internal elastic components compress them, preventing jamming during rotation. During the continuous operation of the first sieve cylinder 1, potassium sulfate crystals easily form tiny clumps or soft agglomerates, and their surface tension or residual moisture easily clogs the first sieve holes 20. The protrusions 19 are slightly larger than the first sieve holes 20, located directly below the second sieve cylinder 2. The bottom of the second sieve cylinder 2 is tangent to the bottom of the inner cavity of the first sieve cylinder 1. At the tangent point, several horizontally arranged protrusions 19 are precisely embedded in the first sieve holes 20 of the same row on the first sieve cylinder 1, allowing for periodic unblocking of the clogged first sieve holes 20.

[0041] Between any two of the aforementioned strip grooves, a plurality of second screen holes 21, with the same size as the first screen hole 20, are also provided. These second screen holes 21 are evenly spaced along the long axis of the second screen cylinder 2. Specifically, when material falls above the second screen cylinder 2, in addition to breaking up agglomerated potassium sulfate crystals, the impact of gravity may cause qualified crystal particles to enter the second screen cylinder 2. Alternatively, during the process of impurities being squeezed into the second screen cylinder 2, qualified crystal particles may also enter the second screen cylinder 2. In this case, because the aperture of the second screen hole 21 is larger than the size of the crystal particles but smaller than the size of the impurities, the second screen hole 21 can allow the qualified crystal particles to fall out or be thrown out by centrifugal force, while retaining the impurities in the second screen cylinder 2.

[0042] The material guiding assembly includes a material guiding unit and a material guiding pipe 3. The bottom end of the material guiding pipe 3 has an opening, the length of which is the same as the length of the second screen cylinder 2. Specifically, the material guiding unit draws the material into the material guiding pipe 3. The slit-like opening forces the material to form a thin, evenly distributed layer above the second screen cylinder 2, ensuring uniform material distribution and crushing, and reducing the reduction in screening efficiency caused by uneven distribution.

[0043] Annular baffles 22 are also provided on the outer periphery of both ends of the first screen cylinder 1. Specifically, during the rotation of the first screen cylinder 1, the annular baffles 22 can ensure that the material will not fall out from both sides of the first screen cylinder 1, thus ensuring the normal screening process of the material.

[0044] The support base 9 is provided with a material collection trough notch 23, which is located directly below the first screen cylinder 1. Specifically, a material collection device is provided below the material collection trough notch 23 for collecting potassium sulfate crystal particles that meet the requirements. At the same time, after one operation cycle, the second screen cylinder 2 is removed and the impurities inside are cleaned to ensure that the subsequent screening process can proceed normally.

[0045] The support base 9 is also provided with a second support frame 24, which is connected to one end of the second screen cylinder 2 via a rotating shaft. Specifically, the second support frame 24 and the first support frame 7 are arranged opposite to the first screen cylinder 1. Since the first screen cylinder 1 has a mounting bracket 5 facing the first support frame 7, and the mounting bracket 5 rotates with the rotation of the first screen cylinder 1, the second support frame 24 is set at the other end of the first screen cylinder 1 to ensure the normal installation of the second screen cylinder 2.

[0046] Example 2, based on Example 1, proposes a method for using a high-purity, rapidly soluble potassium sulfate sieving device, including the following steps:

[0047] S1: Start the drive motor 11, which drives the rotating shaft 6 to rotate through the rotating belt 12. This causes the first screen cylinder 1 to rotate in the forward direction while the second screen cylinder 2 rotates in the reverse direction. The potassium sulfate material to be screened is introduced into the first screen cylinder 1 through the feed pipe 3. Under the action of gravity, the material impacts the side wall of the second screen cylinder 2, thus achieving gravity-induced crushing of the agglomerates.

[0048] S2: Crystal particles with a qualified particle size are less than 0.5mm. The aperture of the first sieve hole 20 is 0.5mm. Qualified crystal particles and small crushed particles are screened through the first sieve cylinder 1 and collected at the collection trough notch 23. Uncrushed lumps move with the material to the extrusion space. The extrusion space gap is 2.5mm. Common impurities such as stone particles, gravel, metal fragments, and hard lumps are larger than 2.5mm. The materials are crushed by the shear force generated between the inner wall of the first sieve cylinder 1 and the outer wall of the second sieve cylinder 2. Hard impurities and some highly moist or damp potassium sulfate crystals, after long-term compaction or repeated wet-dry cycles, form hard lumps similar to stone. Because they cannot be crushed, they are forced into the impurity receiving cavity. The elastic flap 4 is located inside the strip groove, ensuring that the elastic flap 4 can only rotate unidirectionally towards the inner cavity of the second sieve cylinder 2, preventing impurities from being thrown out during the rotation of the second sieve cylinder 2.

[0049] S3: The protrusion 19 further impacts and breaks up the remaining micro-clumps. At the same time, if the protrusion 19 impacts hard impurities in the compression space, it will elastically contract, which can prevent it from being squeezed and stuck.

[0050] S4: When the protrusion 19 rotates with the second screen cylinder 2, it periodically inserts into the first screen hole 20, forcibly pushing out the blockage and realizing continuous self-cleaning. The qualified potassium sulfate crystals after screening are output through the collection trough notch 23, and the impurities are collected in the second screen cylinder 2. After the operation cycle is completed, the second screen cylinder 2 is taken out and the impurities inside are cleaned out to facilitate subsequent operations.

[0051] Example 3: Based on Example 2, this example performs laser particle size analysis on potassium sulfate crystals to analyze the particle size distribution of potassium sulfate after sieving.

[0052] Potassium sulfate raw material was used, with a 25% agglomeration rate (maximum agglomerate size 8mm) and a stone impurity content of 3%. The rotation speed of the first screen cylinder 1 was set to 35 rpm, the rotation speed of the second screen cylinder 2 was set to 40 rpm, and the extrusion space gap was 2.5mm. After running continuously for 1 hour, 3 batches of samples (500g each) were taken from the collection trough notch 23.

[0053] The experimental results showed that the percentage of 0.5mm particles decreased from 18.7% to 0.2%, proving that gravity impact, shear compression, and crushing by protrusion 19 can effectively eliminate agglomeration. In addition, the remaining 0.2% consisted of trace fibrous impurities (not potassium sulfate agglomerates) that were not screened out. The target particle size was 98.5% in the 0.10-0.50mm range (the industry requirement for quick-dissolving potassium fertilizer is ≥95%), meeting production standards. Fine powder smaller than 0.10mm accounted for only 1.3% (12.8% in the raw material), thanks to the trapping of fine powder by the second sieve aperture 21, and the absence of a grinding effect in the compression space, avoiding excessive crystal breakage. With a significant reduction or elimination of agglomerated particles, the dissolution time for the target particle size was 15±3 seconds, a 20-fold improvement in dissolution efficiency compared to the raw material.

[0054] In summary, this invention controls the particle size distribution to concentrate 98.5% of the product in the optimal rapid-dissolving range of 0.10-0.50 mm, while simultaneously achieving trace impurity mixing and zero screen clogging.

[0055] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.

Claims

1. A high-purity, fast-dissolving potassium sulfate sieving device, comprising a first sieve cylinder (1) for sieving potassium sulfate crystal particles and a material guiding assembly, wherein both ends of the first sieve cylinder (1) are open-ended, and the material guiding pipe (3) of the material guiding assembly extends into the upper end of the inner cavity of the first sieve cylinder (1), characterized in that: The first screen cylinder (1) is also provided with a second screen cylinder (2) that rotates in the opposite direction to the first screen cylinder (1). The second screen cylinder (2) is located below the feed pipe (3). The bottom of the second screen cylinder (2) and the bottom of the inner cavity of the first screen cylinder (1) are reserved with a compression space for breaking up potassium sulfate lumps. The inner cavity of the second screen cylinder (2) is provided with an impurity receiving cavity. The side wall of the second screen cylinder (2) is provided with an elastic flap (4) that can be squeezed open. The elastic flap (4) is provided with a protrusion (19) that can be squeezed and stretched. The side wall of the second screen cylinder (2) is provided with several strip grooves that penetrate the inner cavity at equal intervals. The long side of the strip groove is perpendicular to the second screen cylinder (2). The axes are parallel, and the elastic flap (4) is rotated by a torsion spring to cover the strip groove. Several first screen holes (20) are evenly distributed on the first screen cylinder (1). Several second screen holes (21) with the same size as the first screen holes (20) are also provided between any two strip grooves. Impurities that cannot pass through the first screen holes (20) of the first screen cylinder (1) will be pushed by the relative compression of the first screen cylinder (1) and the second screen cylinder (2) to flip the adjacent elastic flap (4) into the inner cavity of the second screen cylinder (2). At this time, the impurities will be pushed into the inner cavity of the second screen cylinder (2). After losing the squeezing force, the elastic flap (4) will restore its elastic deformation and continue to close the strip groove.

2. The high-purity, rapidly soluble potassium sulfate screening device according to claim 1, characterized in that: A mounting frame (5) is fixedly provided at one end of the first screen cylinder (1). A rotating shaft (6) driven by an external power device is provided on the mounting frame (5). The end of the rotating shaft (6) facing the inner cavity of the first screen cylinder (1) is connected to the second screen cylinder (2) through a transmission assembly.

3. The high-purity, rapidly soluble potassium sulfate screening device according to claim 2, characterized in that: It also includes a first support frame (7) for supporting the first screen cylinder (1), the first support frame (7) is provided with a positioning hole (8) for the rotating shaft (6) to pass through, and the first support frame (7) is fixedly installed on the support base (9).

4. The high-purity, rapidly soluble potassium sulfate screening device according to claim 3, characterized in that: A rotating wheel (10) is provided at one end of the rotating shaft (6) away from the first screen cylinder (1), and a drive motor (11) is provided on the support base (9). The rotating wheel (10) is connected to the drive motor (11) through a rotating belt (12).

5. A high-purity, rapidly soluble potassium sulfate screening device according to claim 2, characterized in that: The transmission assembly includes a positioning plate (13), a synchronous pulley (14), a first transmission pulley (15), a second transmission pulley (16), and a driven shaft (17). The rotating shaft (6) passes through the positioning plate (13) and is connected to the synchronous pulley (14). The driven shaft (17) is located below the synchronous pulley (14). The first transmission pulley (15) and the second transmission pulley (16) are located on both sides of the synchronous pulley (14). The driven shaft (17), the first transmission pulley (15), and the second transmission pulley (16) are connected by a transmission belt (18). The driven shaft (17), the first transmission pulley (15), and the second transmission pulley (16) are all located on the inner side of the transmission belt (18), and the synchronous pulley (14) is located on the outer side of the transmission belt (18).

6. The high-purity, rapidly soluble potassium sulfate screening device according to claim 1, characterized in that: The elastic flap (4) is provided with several extruded and retractable protrusions (19). The distribution spacing of the protrusions (19) corresponds to the distribution spacing of the first sieve hole (20). The cross-sectional size of the protrusions (19) is adapted to the size of the first sieve hole (20).

7. A high-purity, rapidly soluble potassium sulfate screening device according to claim 6, characterized in that: Several second sieve holes (21) are arranged at equal intervals along the long axis of the second sieve cylinder (2).

8. The high-purity, rapidly soluble potassium sulfate screening device according to claim 1, characterized in that: The material guiding assembly includes a material guiding unit and a material guiding pipe (3). The bottom end of the material guiding pipe (3) is provided with an opening, the length of which is the same as the length of the second screen cylinder (2).

9. The high-purity, rapidly soluble potassium sulfate screening device according to claim 1, characterized in that: The first screen cylinder (1) is also provided with annular surrounding plates (22) at both ends of its outer periphery.

10. A high-purity, rapidly soluble potassium sulfate screening device according to claim 3, characterized in that: The support base (9) is provided with a material collection trough notch (23), which is located directly below the first screen cylinder (1).

11. A high-purity, rapidly soluble potassium sulfate screening device according to claim 10, characterized in that: The support base (9) is also provided with a second support frame (24), which is connected to one end of the second screen cylinder (2) via a rotating shaft.

12. A method of using the high-purity, rapidly soluble potassium sulfate sieving device according to any one of claims 1-11, characterized in that, Includes the following steps: S1: Feeding and initial crushing. Start the equipment so that the first screen cylinder (1) rotates in the forward direction while the second screen cylinder (2) rotates in the reverse direction. The potassium sulfate material to be screened is introduced into the first screen cylinder (1) through the feed pipe (3). The material impacts the side wall of the second screen cylinder (2) under the action of gravity to carry out the initial crushing of agglomerates. S2: Impurity separation and secondary crushing of agglomerates. Qualified crystal particles and crushed small particles are screened out to the outside and collected by the first screen cylinder (1). Uncrushed agglomerates move with the material to the extrusion space and are crushed by the shear force generated by the inner wall of the first screen cylinder (1) and the outer wall of the second screen cylinder (2). Hard impurities cannot be crushed and are forced into the impurity containment cavity. S3: Fine screening and dynamic unblocking, the protrusion (19) further impacts and breaks up the remaining micro-clumps. At the same time, if the protrusion (19) impacts hard impurities in the compression space, it will undergo elastic contraction. S4: When the protrusion (19) rotates with the second screen cylinder (2), it periodically unblocks and cleans the first screen cylinder (1). The qualified potassium sulfate crystals after screening are screened out and collected by the first screen cylinder (1), and the impurities are collected in the second screen cylinder (2).

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