A phosphammonium process screen bypass device

Abstract

The application discloses a phosphorus ammonium process sieve bypass device for solving the problem of production interruption. The application comprises a distributor, an inlet pipeline, a process sieve, a return chute, a bypass pipeline, a blind plate and a main return belt; the discharge end of the distributor is connected with the feeding end of the inlet pipeline, and the discharge end of the inlet pipeline is connected with the feeding end of the process sieve; the return chute comprises a fine return chute and a coarse return chute, and the coarse return chute is arranged in parallel with the fine return chute; the feeding end of the bypass pipeline is connected with the inlet pipeline, and the discharge end of the bypass pipeline is connected with the fine return chute; the blind plate comprises an inlet blind plate and a bypass blind plate, the inlet blind plate is arranged on the inlet pipeline between the feeding end of the bypass pipeline and the process sieve, and the bypass blind plate is arranged on the bypass pipeline close to the inlet pipeline; the feeding end of the coarse return chute is connected with the coarse material discharge end of the process sieve, and the discharge end is located above the main return belt and is used for collecting unqualified products.

Description

Technical Field

[0001] This application relates to the field of chemical production, and in particular to a bypass device for a phosphate ammonium process sieve. Background Technology

[0002] In the production of ammonium phosphate, process screens are key equipment for product grading. Through a screen structure with specific apertures, they separate the particle size of the pre-processed ammonium phosphate material, effectively distinguishing between qualified fine particles that meet process requirements and unqualified coarse particles that exceed the size limit. The qualified fine particles are directly fed into subsequent drying and cooling processes via a fine return chute, ensuring the stability of the finished product quality. The separated unqualified coarse particles are transported to a return system via a coarse return chute and then sent back to the crushing equipment for reprocessing.

[0003] In the material handling process of traditional ammonium phosphate production systems, the pathway design of the process screen is often characterized by a single feature. Specifically, after the ammonium phosphate material has undergone preliminary processing, it is first initially distributed by a distributor and then directionally conveyed through a single inlet pipe. The material enters the process screen directly along a fixed path within this pipe. At this point, the process screen, using the grading effect of the screen mesh, separates the material into two categories: qualified fine material and unqualified coarse material. After separation, the two types of material are then conveyed separately through fine return chutes and coarse return chutes connected to the screen outlets, respectively.

[0004] However, this traditional design has obvious drawbacks. When the process screen needs to be repaired, cleaned, or malfunctions, the entire production process must be interrupted, causing the production line to stop and seriously affecting production continuity and efficiency. This is especially true in large-scale phosphate fertilizer production plants, where the capacity loss and restart costs caused by a single shutdown are high. Utility Model Content

[0005] To address the aforementioned technical problems, this application discloses a bypass device for a phosphate fertilizer process sieve, used to solve the problem of production interruption.

[0006] This application provides a bypass device for a phosphate fertilizer process screen, comprising: The components include: feeder, inlet pipe, process screen, return chute, bypass pipe, blind flange, and main return belt; The discharge end of the distributor is connected to the inlet end of the inlet pipe, and the discharge end of the inlet pipe is connected to the inlet end of the process screen. The return chute includes a fine return chute and a coarse return chute, and the coarse return chute is connected in parallel with the fine return chute. The feed end of the bypass pipe is connected to the inlet pipe, and the discharge end of the bypass pipe is connected to the fine return chute. The blind flange includes an inlet blind flange and a bypass blind flange. The inlet blind flange is disposed on the inlet pipe between the feed end of the bypass pipe and the process screen. The bypass blind flange is disposed on the bypass pipe near the inlet pipe. The feed end of the coarse return chute is connected to the coarse material discharge end of the process screen, and the discharge end is located above the main return belt, used to collect defective products.

[0007] Optionally, both the inlet pipe and the bypass pipe have supporting structures on their inner walls to support the inlet blind flange and the bypass blind flange.

[0008] Optionally, the support structure includes ribs and triangular reinforcing ribs distributed along the circumference of the pipe; The ribs include supporting ribs and limiting ribs, which are arranged in parallel and opposite to each other and are welded obliquely to the inner wall of the pipe; The distance between the supporting rib and the limiting rib is greater than the thickness of the blind plate, forming a strip-shaped groove into which the blind plate slides. The triangular reinforcing ribs are arranged below the support ribs and above the limiting ribs along the insertion and removal direction of the blind plate.

[0009] Optionally, the device may also include a qualified product chute and a screen collection belt; One end of the qualified product chute is connected to the qualified product discharge end of the process screen, and the other end is located above the screen collection belt.

[0010] Optionally, the discharge end of the coarse return chute is provided with a flow guide shroud, which has a trumpet-shaped structure. The large end of the flow guide shroud is connected to the discharge end of the coarse return chute, and the small end faces the middle of the main return belt.

[0011] Optionally, the blind plate includes a plate body and a handle, the handle being vertically welded to the middle position of the plate body.

[0012] Optionally, the edge of the plate is provided with a sealing groove, and a rubber sealing ring is adapted to fit in the sealing groove.

[0013] Optionally, the coarse return chute is also equipped with a three-roll mill for grinding the material.

[0014] Optionally, both the imported blind flange and the bypass blind flange are made of 316L stainless steel.

[0015] Optionally, the inner walls of both the coarse return chute and the fine return chute are provided with a wear-resistant coating.

[0016] As can be seen from the above technical solutions, the embodiments of this application have the following advantages: This application utilizes an added bypass pipe and a double-blind-plate structure (inlet blind plate and bypass blind plate) to create a switchable material path. When the process screen requires maintenance, cleaning, or malfunctions, the inlet blind plate can be closed to block the path to the process screen, while the bypass blind plate is opened to allow material to directly enter the fine return chute via the bypass pipe. This avoids the need for shutdown in traditional single-path designs, reduces capacity loss due to equipment maintenance, and prevents disruptions to production continuity. Switching between the main path and bypass path is achieved by opening and closing the blind plates, eliminating the need for complex automatic control systems and adapting to the working conditions of phosphate fertilizer production sites. The blind plate placement ensures no material leakage or residue during switching, and the operation process is intuitive, allowing for rapid path conversion and improved production efficiency. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the 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.

[0018] Figure 1 This is a schematic diagram of a bypass device for a phosphate fertilizer process screen according to this application; Figure 2 This is a schematic diagram of the blind plate in a bypass device for a phosphate fertilizer process screen according to this application; Figure 3 This is a bottom view schematic diagram of the support structure in a bypass device for a phosphate fertilizer process screen according to this application. Figure 4 This is a top view schematic diagram of the support structure in a bypass device for a phosphate fertilizer process screen according to this application. Figure 5 This is a cross-sectional schematic diagram of the support structure in a phosphate ammonium process sieve bypass device according to this application; Figure 6 This is a schematic diagram of the movement structure of the blind plate in a bypass device for a phosphate fertilizer process screen according to this application; Figure 7 This is a schematic diagram showing the state of the blind plate during normal operation of a phosphate fertilizer process sieve bypass device according to this application. Figure 8 This is a schematic diagram showing the status of the blind plate during maintenance of the process screen in the bypass device of the ammonium phosphate process screen of this application.

[0019] In the diagram: 01. Distributor; 02. Inlet pipe; 03. Process screen; 041. Coarse return chute; 042. Fine return chute; 05. Bypass pipe; 06. Blind flange; 061. Inlet blind flange; 062. Bypass blind flange; 063. Plate body; 064. Handle; 065. Sealing groove; 066. Rubber sealing ring; 07. Main return belt; 08. Support rib; 09. Limiting rib; 010. Triangular reinforcing rib; 011. Strip groove; 012. Qualified product chute; 013. Screen collection belt; 014. Three-roll mill. Detailed Implementation

[0020] In this application, the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and other terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only used to describe the relative positional relationship between the components or parts and do not specifically limit the specific installation orientation of each component or part.

[0021] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0022] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; 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, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0023] Furthermore, the structures, proportions, sizes, etc., drawn in the accompanying drawings of this application are only used to complement the content disclosed in the specification for those skilled in the art to understand and read, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modification to the structure, change in the proportional relationship, or adjustment of the size, without affecting the effects and purposes that this application can produce, should still fall within the scope of the technical content disclosed in this application.

[0024] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] To address the aforementioned technical problems, this application provides a bypass device for a phosphate fertilizer process sieve, which solves the problem of production interruption.

[0026] Please see Figure 1 - Figure 8 This application provides a bypass device for a phosphate fertilizer process screen, comprising: 01. Distributor; 02. Inlet pipe; 03. Process screen; 04. Return chute; 05. Bypass pipe; 06. Blind flange; and 07. Main return belt. The discharge end of the distributor 01 is connected to the inlet end of the inlet pipe 02, and the discharge end of the inlet pipe 02 is connected to the inlet end of the process screen 03. The return chute includes a fine return chute 042 and a coarse return chute 041, with the coarse return chute 041 and the fine return chute 042 connected in parallel. The feed end of the bypass pipe 05 is connected to the inlet pipe 02, and the discharge end of the bypass pipe 05 is connected to the fine return chute 042. Blind flange 06 includes inlet blind flange 061 and bypass blind flange 062. Inlet blind flange 061 is installed on inlet pipe 02 between the feed end of bypass pipe 05 and process screen. Bypass blind flange 062 is installed on bypass pipe 05 near inlet pipe 02. The feed end of the coarse return chute 041 is connected to the coarse discharge end of the process screen 03. The discharge end is located above the main return belt 07 and is used to collect defective products.

[0027] During normal production, the inlet blind flange 061 is in the open state, and the bypass blind flange 062 is in the closed state. After being distributed by the distributor 01, the phosphate material enters the process screen 03 through the inlet pipe 02. After being classified by the screen surface, the qualified fine material enters the qualified product chute 012 from the qualified product outlet end of the process screen 03, and is finally transported to the subsequent process by the screen collection belt 013; the unqualified coarse material falls into the main return belt 07 through the coarse return chute 041, and is reprocessed after being pre-ground by the three-roll mill 014 on the coarse return chute 041.

[0028] When the process screen 03 needs maintenance, cleaning, or malfunctions, switch to bypass mode: close the inlet blind flange 061 to block the path to the process screen 03, and at the same time open the bypass blind flange 062, so that the material can enter the fine return chute 042 directly from the inlet pipe 02 through the bypass pipe 05, and merge with the fine material path when the process screen 03 is working normally, so as to ensure that the material is continuously transported to the subsequent process and avoid production line shutdown.

[0029] The entire process achieves pathway switching through the opening and closing of blind flange 06, with the support structure ensuring stable sealing of blind flange 06. The design of wear-resistant coating and sealing groove 065 reduces material leakage and equipment wear, ultimately achieving seamless switching between normal screening and emergency bypass, taking into account both production continuity and grading accuracy.

[0030] This application utilizes an added bypass pipe 05 and a double blind flange structure 06 (inlet blind flange 061 and bypass blind flange 062) to create a switchable material path. When the process screen 03 requires maintenance, cleaning, or malfunctions, the inlet blind flange 061 can be closed to block the path to the process screen 03, while the bypass blind flange 062 is opened to allow material to directly enter the fine return chute 042 via the bypass pipe 05. This avoids the need for machine shutdown in traditional single-path designs, reduces capacity loss due to equipment maintenance, and prevents disruption to production continuity. Switching between the main path and bypass path is achieved by opening and closing the blind flange 06, eliminating the need for a complex automatic control system and adapting to the working conditions of phosphate fertilizer production sites. The placement of the blind flange 06 ensures no material leakage or residue during switching, and the operation process is intuitive, allowing for rapid path conversion and improved production efficiency.

[0031] In an optional embodiment, the inner walls of both the inlet pipe 02 and the bypass pipe 05 are provided with support structures to support the inlet blind flange 061 and the bypass blind flange 062.

[0032] On the inner walls of the inlet pipe 02 and the bypass pipe 05, the support structure is welded from metal components of the same material as the pipes. For the inlet pipe 02, the support structure has three sets of identical support components evenly distributed circumferentially along the inner wall of the inlet pipe 02, each set of components corresponding to a section of the edge of the blind flange 06. When the inlet blind flange 061 is installed, the edge of the blind flange 06 can be placed stably on the bearing surface of the support structure, and the impact pressure of the material on the blind flange 06 is dispersed through the surface contact between the support structure and the blind flange 06. For the bypass pipe 05, the support structure on the inner wall of the bypass pipe 05 adopts the same design standard as the inlet pipe 02, ensuring that the bypass blind flange 062 can fit tightly against the inner wall of the pipe after insertion. This ensures that the blind flange 06 will not shift during material transportation and provides a stable guiding effect for the insertion and removal operation of the blind flange 06, avoiding jamming of the blind flange 06 due to pipe vibration.

[0033] In an optional embodiment, the support structure includes ribs and triangular reinforcing ribs 010 distributed along the circumference of the pipe; the ribs include supporting ribs 08 and limiting ribs 09, which are arranged in parallel opposite directions and obliquely welded to the inner wall of the pipe; the spacing between the supporting ribs 08 and the limiting ribs 09 is larger than the thickness of the blind flange 06, forming a strip-shaped groove 011 into which the blind flange 06 slides; the triangular reinforcing ribs 010 are arranged below the supporting ribs 08 and above the limiting ribs 09 along the insertion and withdrawal direction of the blind flange 06.

[0034] The ribs of the supporting structure are cut from steel plates. The lengths of the supporting ribs 08 and the limiting ribs 09 are adapted to the inner diameter of the pipe and are welded and fixed obliquely along the inner wall of the pipe. The spacing between the supporting ribs 08 and the limiting ribs 09 is larger than the thickness of the blind flange 06, forming a strip-shaped groove 011 of uniform width. The groove depth is sufficient to accommodate the entire edge of the blind flange 06. When the blind flange 06 is inserted, the edge slides smoothly into the groove along its length. The supporting ribs 08 bear the main weight of the blind flange 06, while the limiting ribs 09 restrict the radial movement of the blind flange 06 within the pipe. The triangular reinforcing ribs 010 are made of right-angled triangular steel plates, with the right-angled sides welded to the inner wall of the pipe and the ribs respectively. The triangular reinforcing ribs 010 below the supporting ribs 08 are spaced 20cm apart, while the triangular reinforcing ribs 010 above the limiting ribs 09 are staggered with the reinforcing ribs below the supporting ribs 08. The stability of the triangular structure enhances the load-bearing capacity of the ribs and prevents deformation of the ribs due to material impact after long-term use. In an optional embodiment, the apparatus further includes a qualified product chute 012 and a screen collection belt 013; one end of the qualified product chute 012 is connected to the qualified product discharge end of the process screen 03, and the other end is located above the screen collection belt 013.

[0035] In this embodiment, the qualified product chute 012 is made of wear-resistant cast iron. Its diameter is designed according to the qualified product output of the process screen 03. The inlet end of the qualified product chute 012 is sealed to the qualified product outlet of the process screen 03 via a flange, and a high-temperature resistant asbestos gasket is installed at the connection to prevent dust leakage. The qualified product chute 012 is arranged at an angle, and its inner wall is polished to reduce material retention. The outlet end of the qualified product chute 012 extends directly above the screen collection belt 013. The screen collection belt 013 is a rubber conveyor belt with anti-slip textures on its surface. It works in conjunction with the qualified product chute 012 to form an independent qualified product conveying path, achieving material diversion with the return system.

[0036] In an optional embodiment, the discharge end of the coarse return chute 041 is provided with a flow guide shroud, which has a trumpet-shaped structure. The large end of the flow guide shroud is connected to the discharge end of the coarse return chute 041, and the small end faces the middle of the main return belt 07.

[0037] The guide shroud at the discharge end of the coarse return chute 041 is made of stamped stainless steel plate, with an overall trumpet-shaped gradient structure. The diameter of the larger end is the same as the diameter of the discharge end of the coarse return chute 041, and it is fixedly connected to the end of the chute by welding. The connection is fully welded to ensure airtightness. The axis of the guide shroud is perpendicular to the surface of the main return conveyor belt 07. The interior of the guide shroud is smooth and without protrusions, ensuring that the coarse material slides smoothly down the side wall under gravity. The converging effect of the smaller end precisely guides the material to the middle area of ​​the main return conveyor belt 07.

[0038] In an optional embodiment, the blind plate 06 includes a plate body 063 and a handle 064, the handle 064 being vertically welded to the middle of the plate body 063.

[0039] In an optional embodiment, the edge of the plate 063 is provided with a sealing groove 065, and a rubber sealing ring 066 is adapted to fit inside the sealing groove 065.

[0040] The blind flange 06 has a plate body 063 made of sheet metal, and a handle 064 made of round steel. One end of the handle is welded to the center of the plate body 063, and the weld is made using a double-sided full welding process to ensure that the connection strength is sufficient to withstand the force when inserting or removing the blind flange 06. The end of the handle 064 is also covered with a rubber anti-slip sleeve with a grid pattern on the surface. This prevents the operator's hand from slipping and provides some heat insulation protection in low-temperature environments, facilitating quick and easy manual insertion and removal of the blind flange 06.

[0041] The edge of plate 063 is circumferentially machined with a sealing groove 065, within which a rubber sealing ring 066 is installed. The rubber sealing ring 066 is made of wear-resistant nitrile rubber, with a circular cross-section and a diameter larger than the depth of the sealing groove 065, allowing it to maintain a slightly compressed state after being embedded in the sealing groove 065. The outer side of the sealing ring is flush with the edge of plate 063. When the blind flange 06 slides into the pipe, the sealing ring can fit tightly against the inner wall of the pipe, filling the gap through the elastic deformation of the rubber, effectively preventing material particles from leaking from the gap between plate 063 and the pipe.

[0042] In an optional embodiment, a three-roll mill 014 is also provided on the coarse return chute 041 for grinding the material.

[0043] A three-roll mill 014 is connected in series at the middle of the coarse return chute 041. The feed inlet of the three-roll mill 014 is connected to the upstream chute via a flange, and the discharge outlet is connected to the downstream chute. The three rollers of the three-roll mill 014 are arranged in an equilateral triangle, and the roller surfaces are made of high-chromium cast iron and have undergone quenching treatment. The roller spacing can be flexibly adjusted within a certain range through an adjustment mechanism. When unqualified coarse material passes through, the relative rotation of the rollers squeezes and grinds the material, crushing large phosphate particles to the particle size that meets the process requirements, reducing the processing load of subsequent crushing equipment and improving the efficiency of return material processing.

[0044] In an optional embodiment, both the inlet blind flange 061 and the bypass blind flange 062 are made of 316L stainless steel.

[0045] Both the imported blind flange 061 and bypass blind flange 062 are integrally machined from 316L stainless steel sheet. This material contains approximately 2-3% molybdenum, exhibiting excellent corrosion resistance and oxidation resistance. Addressing the acidic gases and humid conditions present in the ammonium phosphate production environment, 316L stainless steel effectively resists phosphate ion corrosion from the material, avoiding the problems of easy rusting and short lifespan associated with traditional carbon steel blind flange 06. The surface of plate 063 undergoes pickling and passivation treatment, forming a uniform oxide film. This improves wear resistance and reduces material adhesion to the surface of plate 063, extending the maintenance cycle of blind flange 06 and ensuring good sealing performance and structural strength during long-term use.

[0046] In an optional embodiment, the inner walls of both the coarse return chute 041 and the fine return chute 042 are provided with a wear-resistant coating.

[0047] Both the coarse return chute 041 and the fine return chute 042 have an inner wall coated with a wear-resistant coating. This coating is a mixture of tungsten carbide and nickel-based alloy, applied to the inner wall using a supersonic flame spraying process. The coating's surface hardness and bonding strength are sufficient to withstand the continuous erosion and friction of the phosphate material. The inner wall of the chute is sandblasted before coating to ensure a strong bond between the coating and the substrate, preventing peeling. For easily worn areas such as elbows and diameter changes in the chute, the coating thickness is increased, significantly extending the chute's service life through differentiated protection and reducing maintenance costs caused by pipe wear.

[0048] It should be noted that the above description of the disclosed embodiments enables those skilled in the art to implement or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A bypass device for a phosphate fertilizer process sieve, characterized in that, include: The components include: feeder, inlet pipe, process screen, return chute, bypass pipe, blind flange, and main return belt; The discharge end of the distributor is connected to the inlet end of the inlet pipe, and the discharge end of the inlet pipe is connected to the inlet end of the process screen. The return chute includes a fine return chute and a coarse return chute, and the coarse return chute is connected in parallel with the fine return chute. The feed end of the bypass pipe is connected to the inlet pipe, and the discharge end of the bypass pipe is connected to the fine return chute. The blind flange includes an inlet blind flange and a bypass blind flange. The inlet blind flange is disposed on the inlet pipe between the feed end of the bypass pipe and the process screen. The bypass blind flange is disposed on the bypass pipe near the inlet pipe. The feed end of the coarse return chute is connected to the coarse material discharge end of the process screen, and the discharge end is located above the main return belt, used to collect defective products.

2. The phosphate fertilizer process sieve bypass device according to claim 1, characterized in that, Both the inlet pipe and the bypass pipe have supporting structures on their inner walls to support the inlet blind flange and the bypass blind flange.

3. The phosphate fertilizer process sieve bypass device according to claim 2, characterized in that, The supporting structure includes ribs and triangular reinforcing ribs distributed along the circumference of the pipe; The ribs include supporting ribs and limiting ribs, which are arranged in parallel and opposite to each other and are welded obliquely to the inner wall of the pipe; The distance between the supporting rib and the limiting rib is greater than the thickness of the blind plate, forming a strip-shaped groove into which the blind plate slides. The triangular reinforcing ribs are arranged below the support ribs and above the limiting ribs along the insertion and removal direction of the blind plate.

4. The phosphate fertilizer process sieve bypass device according to claim 1, characterized in that, The device also includes a qualified product chute and a screen collection belt; One end of the qualified product chute is connected to the qualified product discharge end of the process screen, and the other end is located above the screen collection belt.

5. The phosphate fertilizer process sieve bypass device according to claim 1, characterized in that, The discharge end of the coarse return chute is equipped with a flow guide shroud, which has a trumpet-shaped structure. The large end of the flow guide shroud is connected to the discharge end of the coarse return chute, and the small end faces the middle of the main return belt.

6. The phosphate fertilizer process sieve bypass device according to claim 1, characterized in that, The blind plate includes a plate body and a handle, with the handle vertically welded to the middle position of the plate body.

7. The phosphate fertilizer process sieve bypass device according to claim 6, characterized in that, The edge of the plate is provided with a sealing groove, and a rubber sealing ring is adapted to fit in the sealing groove.

8. The phosphate fertilizer process sieve bypass device according to claim 1, characterized in that, The coarse return chute is also equipped with a three-roll mill for grinding the material.

9. The phosphate fertilizer process sieve bypass device according to claim 1, characterized in that, Both the imported blind flange and the bypass blind flange are made of 316L stainless steel.

10. The phosphate fertilizer process sieve bypass device according to claim 1, characterized in that, The inner walls of both the coarse return chute and the fine return chute are provided with a wear-resistant coating.

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