A foreign object trap for a delivery line

Abstract

The utility model discloses a kind of foreign matter capturing devices of conveying pipeline, including separator body and end pipeline.The separator body both ends are connected in conveying pipeline, and end pipeline is located in the lower part of separator body.The device is by conveying pipeline cross section mutation to cause local low flow area, and foreign matter in separation conveying medium enters end pipeline.Especially, the conveying medium is air, and the conveying substance is cellulose acetate flake, the diameter of separator body is two to five times of the diameter of conveying pipeline, the lower part of separator body reducing pipe has hand hole, and end pipeline bottom has blind plate, for cleaning and collecting accumulated foreign matter.The foreign matter capturing device of the cellulose acetate flake conveying pipeline of the utility model is convenient to use, separation effect is good, maintenance workload is small, and the purpose of separating foreign matter in cellulose acetate flake conveying process is achieved.

Description

Technical Field

[0001] This application belongs to the field of chemical production technology and relates to a foreign object capture device for pipelines in a production system. Background Technology

[0002] In the production process of cellulose diacetate tablets for tobacco (hereinafter referred to as "diacetate tablets"), the finished diacetate tablets are conveyed by a Roots blower through a series of pipelines to a large silo. However, during this process, due to mechanical failures or other reasons in upstream production units, foreign objects such as bolts and sheet metal may get mixed into the finished diacetate tablets and enter the large silo along with them, affecting subsequent processing of the finished diacetate tablets. Similar phenomena are widespread in the conveying pipelines of the chemical industry. The presence of these foreign objects not only reduces product quality but may also damage subsequent processing equipment and affect production efficiency.

[0003] In existing technologies, methods such as filtration and magnetic attraction are commonly used to remove foreign objects from pipelines. Although these methods can remove foreign objects from pipelines, the technical means are too complicated, and the separation effect and applicable scenarios are limited, failing to solve this problem conveniently and effectively. Utility Model Content

[0004] This invention aims to provide a novel foreign object capture device for conveying pipelines. The device is easy to operate, has high capture efficiency, and can conveniently and effectively separate and remove foreign objects during the conveying of acetate tablets. It can also be flexibly applied to conveying pipelines in more production scenarios, thereby ensuring the purity of the product and the continuity of the production process.

[0005] The technical solution proposed by this utility model includes: a foreign object capture device for a conveying pipeline, comprising: a separator body, an end pipeline for collecting foreign objects separated by the separator body, both ends of the separator body being connected to the conveying pipeline, the end pipeline being located at the lower part of the separator body, the cross-sectional area of ​​the separator body being larger than the cross-sectional area of ​​the conveying pipeline, and the foreign objects in the conveying medium being separated and entering the end pipeline by a sudden change in the cross-section of the conveying pipeline.

[0006] Furthermore, the medium transported in the transport pipeline is air.

[0007] Furthermore, the separator body is composed of a lower reducing pipe, a separator speed-reducing pipe, and an upper reducing pipe connected in sequence, with the middle part of the separator body being the separator speed-reducing pipe.

[0008] Furthermore, the bottom of the terminal pipeline has a removable blind plate for cleaning foreign objects collected in the terminal pipeline.

[0009] Furthermore, the diameter of the separator deceleration pipe is 2 to 5 times the diameter of the delivery pipeline.

[0010] Furthermore, the deceleration tube of the separator is 1 to 2 meters long.

[0011] Furthermore, a hand hole is provided on the side of the lower reducing pipe, and the hand hole is sealed with a removable hand hole blind plate for cleaning foreign objects inside the separator body.

[0012] Furthermore, the separator body has an upper interface and a lower interface at both ends that can be connected to the conveying pipeline respectively. The upper interface is connected to the bottom of the upper conveying pipeline through an upper flange or an upper clamp, and the lower interface is connected to the top of the horizontal bend of the lower conveying pipeline through a lower flange or a lower clamp.

[0013] Furthermore, the terminal pipeline is located below the separator body and is used to store foreign objects that separate and fall from the separator body.

[0014] Furthermore, the terminal pipeline is connected to the horizontal conveying bend of the lower conveying pipeline, and the horizontal conveying bend and the terminal pipeline have the same diameter.

[0015] Furthermore, the connection between the end pipeline and the horizontal conveying bend is made by electric welding.

[0016] Furthermore, the separator deceleration tube is circumferentially arranged with spiral guide plates at 30-45 degrees to improve the foreign matter separation efficiency.

[0017] Furthermore, the separator deceleration tube is a stepped deceleration tube, which is composed of multiple deceleration tubes with gradually increasing diameters connected together. Through the step-like attenuation of the flow velocity in the interstage deceleration tubes, a velocity gradient field is formed.

[0018] Furthermore, the diameter ratio of two adjacent sections of the stepped speed-reducing tube is 1.2 to 1.5.

[0019] Furthermore, the foreign object capture device in the delivery pipeline delivers cellulose diacetate sheets as the conveying material.

[0020] The working principle of this utility model's technical solution:

[0021] 1. Principle of fluid dynamics separation

[0022] When the two-phase flow of acetic acid / air passes through a region of abrupt change in the pipe cross-section (such as a diffuser or a sudden expansion chamber), according to the continuity equation (Q = Av) and Bernoulli's theorem, the flow velocity will drop sharply to 1 / (D) of the inlet velocity in the expansion section. 2 / d 2 (D is the diameter of the expanded section, and d is the diameter of the original pipeline). This sharp decrease in flow velocity (typically from 25 m / s to <5 m / s) leads to a significant reduction in fluid kinetic energy, forming a low-pressure vortex stability zone.

[0023] 2. Stokes settling velocity

[0024] The terminal settling velocity v of the foreign object s Determined by Stokes' Law:

[0025]

[0026] Where ρ p For the density of the foreign object, ρ f Let ρ be the air density, r be the radius of the foreign object, and η be the air viscosity. The denser the foreign object, the faster its settling velocity v. s The higher the value, the easier it is to separate.

[0027] Continuity equation: An increase in the cross-sectional area of ​​the pipe leads to a decrease in flow velocity. If the original pipe diameter is d, and the expanded diameter is nd, then the flow velocity u′ decreases to:

[0028] u′=u0 / n 2

[0029] Where u0 is the original duct wind speed and n is the diameter expansion factor.

[0030] 3. Key threshold conditions

[0031] The separation of foreign objects requires the following two conditions to be met:

[0032] (1) Flow velocity condition: The expanded flow velocity u must be lower than the settling velocity of the foreign object v. s ,Right now:

[0033]

[0034] (2) Time condition: The foreign object needs sufficient time to settle to the bottom of the pipe within the enlarged section. Settling time t 沉降 =D / v s (D is the diameter of the expanded section), while the airflow residence time t 停留 =L / u′, must satisfy:

[0035]

[0036] Therefore, the separator length L must satisfy:

[0037]

[0038] 4. Impact of key factors

[0039] Diameter expansion factor n: The larger n is, the lower the flow velocity u′, and the easier it is to satisfy u′≤v s However, this requires a longer L (since L ∝ 1 / n). A trade-off needs to be made.

[0040] Foreign matter density ρ p ρ pThe higher, v s The larger the value, the smaller the threshold n can be, and the shorter the required L is.

[0041] Delivery velocity u0: The higher u0 is, the greater n or the longer L is required to counteract the effect of high-speed airflow.

[0042] Separator length L: Insufficient length will cause foreign objects to be carried out before settling. It is necessary to ensure that L ≥ u0d / (nv) s Determine the lower limit.

[0043] 5. Design parameter optimization

[0044] Critical diameter enlargement factor:

[0045]

[0046] When n>n 临界 At that time, the flow velocity condition is automatically met.

[0047] Critical separator length:

[0048]

[0049] In practical design, L > L should be taken. 临界 To ensure effective separation.

[0050] 6. Simplified Analysis of Examples

[0051] When u0 = 20 m / s, the foreign object v s =4m / s, original pipeline diameter d = 0.2m:

[0052] Critical scaling factor: n 临界 The value of n is 2. Taking into account various factors, the value of n in this utility model is 2 to 5 times.

[0053] Critical length: In practice, the design requires L>0.5m. Considering various factors, the value of L in this utility model is 1 to 2m.

[0054] 7. Other influencing factors

[0055] Guide vane angle: A circumferential arrangement of 30-45° spiral guide plates can improve separation efficiency by 18%.

[0056] Gradient flow field control: Multi-stage expansion sections are arranged in a stepped manner, with each stage gradually expanding. The expansion ratio of each stage is 1.2 to 1.5 times. Through the step-like attenuation of the flow velocity between stages, the flow velocity of each stage is reduced by 40% to 60%, forming a velocity gradient field. The separation efficiency of the two-stage or three-stage gradually expanding structure is more than 20% higher than that of the single-stage scheme.

[0057] Compared with the prior art, the beneficial effects of this utility model are:

[0058] The device of this utility model, through its unique design, not only improves the efficiency of foreign object separation and achieves the purpose of separating foreign objects during the transportation process, but also simplifies the maintenance procedure and reduces downtime, thereby significantly improving production efficiency and product quality. Attached Figure Description

[0059] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments 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. They are used together with the embodiments of this utility model to explain this utility model and do not constitute a limitation on this utility model.

[0060] Figure 1 : A schematic diagram of an embodiment 1 of a foreign object capture device for a pipeline.

[0061] Figure 2 : A schematic diagram of an embodiment 2 of a foreign object capture device for a pipeline.

[0062] Figure 3 : A schematic diagram of an embodiment 3 of a foreign object capture device for a pipeline.

[0063] Figure 4 : A schematic diagram of an embodiment 4 of a foreign object capture device for a pipeline.

[0064] In the figure: 2. Foreign object capture device for conveying pipeline in Example 2; 3. Foreign object capture device for conveying pipeline in Example 3; 4. Foreign object capture device for conveying pipeline in Example 4; 10. Foreign object capture device for conveying pipeline in Example 1; 11. Separator body; 12. Terminal pipeline; 111. Separator speed reduction pipe; 1111. First-stage speed reduction pipe of separator; 1112. Second-stage speed reduction pipe of separator; 114. Manhole; 115. Spiral guide plate; 121. Blind flange; 1121. Upper reducer pipe; 1122. Lower reducer pipe; 1123. Middle reducer pipe; 1131. Upper flange; 1132. Lower flange; 1133. Upper clamp; 1134. Lower clamp; 1141. Manhole blind flange. Detailed Implementation

[0065] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not the entire structure. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0066] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0067] Example 1 provides a foreign object capture device 10 for a diacetate tablet delivery pipeline, such as Figure 1 As shown, the foreign object capture device 10 for the diacetate tablet delivery pipeline includes: a separator body 11, located at the lower part of the separator body, and an end pipeline 12 for collecting foreign objects separated by the separator body. Both ends of the separator body are connected to the delivery pipeline. The cross-sectional area of ​​the separator body 11 is larger than that of the delivery pipeline. By abruptly changing the cross-section of the delivery pipeline, a local low flow velocity zone is triggered, and foreign objects in the delivery medium are separated and enter the end pipeline 12.

[0068] Specifically, the separator body 11 includes a separator speed-reducing pipe 111, an upper reducing pipe 1121, a lower reducing pipe 1122, an upper flange 1131, and a lower flange 1132. The separator speed-reducing pipe 111 is located in the middle of the separator body 11. The separator speed-reducing pipe 111 has a diameter of 40 cm and a length of 1 meter. The diameter of the separator speed-reducing pipe 111 is twice the diameter of the diethyl acetate conveying pipeline. By abruptly changing the cross-section of the pipe, a local low-velocity zone is created to locally reduce the conveying air velocity of the diethyl acetate, thereby achieving the purpose of separating foreign objects. The separator body has an upper flange 1131 and a lower flange 1132, which are respectively connected to the bottom of the upper conveying pipeline and the top of the horizontal bend of the lower conveying pipeline to ensure the stability and sealing of the device. The separator speed reduction pipe 111 and the upper flange 1131 are connected by the upper reducer pipe 1121, and the separator speed reduction pipe 111 and the lower flange 1132 are connected by the lower reducer pipe 1122.

[0069] The separator body 11 is connected to the top of the horizontal bend of the lower conveying pipeline of the diacetate tablets via the lower flange 1132. The diacetate tablets are blown from the horizontal bend into the foreign object capture device.

[0070] The separator body 11 is connected to the bottom of the upper conveying pipeline of diacetate tablets through the upper flange 1131. After the finished diacetate tablets are separated from foreign matter, they are blown to the upper conveying pipeline.

[0071] A handhole 114 is provided on the side of the lower reducing pipe 1121 of the separator body 10. The handhole is sealed with a handhole blind flange 1141. During normal production, the handhole blind flange 1141 is sealed to keep the pipeline airtight. During periodic cleaning, the handhole blind flange 1141 can be opened to remove foreign objects from the inside of the separator body 10.

[0072] The terminal pipeline 12 is vertically installed on the horizontal conveying bend of the two-acetate sheet, located directly below the separator body 11. The diameter of the terminal pipeline 12 is the same as that of the horizontal conveying bend of the two-acetate sheet. After drilling holes in the horizontal conveying bend of the two-acetate sheet, it is connected by electric welding and used to store foreign objects separated and falling from the foreign object separator body 11. The bottom of the terminal pipeline 12 has a blind plate 121, which is used to keep the pipeline sealed during normal production. During periodic cleaning, the blind plate 121 can be opened to clean the foreign objects collected by the terminal pipeline 12.

[0073] Example 2 provides a foreign object capture device 2 for a diacetate tablet delivery pipeline. The improved features are specifically described below:

[0074] In Example 2, as Figure 2 As shown, the separator body 11 is installed at an angle between the horizontal conveying bend of the two acetic acid plates and the upper conveying pipeline. Due to the angled installation, the conveying speed of the foreign objects to be separated needs to be slowed down. Correspondingly, the conveying distance of the foreign objects to be separated needs to be increased. The diameter of the separator deceleration pipe 111 is 5 times the diameter of the two acetic acid plates conveying pipeline, and the separator deceleration pipe 111 is 2 meters long.

[0075] The separator body 11 is connected to the bottom of the upper conveying pipeline of the diethyl acetate flakes via the upper flange 1131. After the finished diethyl acetate flakes are separated from foreign matter, they are blown to the upper conveying pipeline.

[0076] The terminal pipeline 12 is installed below the separator body 11 and is used to store foreign objects that are separated and fall from the foreign object separator body 11. The bottom of the terminal pipeline 12 has a blind plate 121, which is used to keep the pipeline sealed during normal production. During periodic cleaning, the blind plate 121 can be opened to clean the accumulated foreign objects collected in the terminal pipeline 12.

[0077] The components used in Example 2 that have the same reference numerals as those in Example 1 indicate that they have the same or similar structural features.

[0078] Example 3 provides a foreign object capture device 3 for a diacetate tablet delivery pipeline. The improved features are specifically described below:

[0079] In Example 3, as Figure 3As shown, a 30-45 degree spiral guide plate 115 is arranged circumferentially on the inner wall of the separator deceleration pipe 111 to improve the foreign matter separation efficiency of the separator.

[0080] The upper interface of the separator body 11 is connected to the bottom of the upper conveying pipeline through the upper clamp 1133, and the lower interface is connected to the top of the horizontal bend of the lower conveying pipeline through the lower clamp 1134. The clamp connection facilitates disassembly, assembly, and maintenance.

[0081] The components used in Example 3 that have the same reference numerals as those in Example 1 indicate that they have the same or similar structural features.

[0082] Example 4 provides a foreign object capture device 4 for a diacetate tablet delivery pipeline. The improved features are specifically described below:

[0083] In Example 4, as Figure 4 As shown, the separator body 11 is composed of a lower variable diameter pipe 1122, a first-stage velocity reduction pipe 1111, a middle variable diameter pipe 1123, a second-stage velocity reduction pipe 1112, and an upper variable diameter pipe 1121 connected in sequence. The diameter ratio between the first-stage velocity reduction pipe 1111 and the second-stage velocity reduction pipe 1112 ranges from 1.2 to 1.5. In this embodiment, the diameter ratio between the first-stage velocity reduction pipe 1111 and the lower conveying pipeline is 1.5 times, and the diameter ratio between the second-stage velocity reduction pipe 1112 and the first-stage velocity reduction pipe 1111 is 1.5 times. The lengths of the second-stage velocity reduction pipe 1112 and the first-stage velocity reduction pipe 1111 are both 0.5 meters. A velocity gradient field is formed by the step-like attenuation of the interstage flow velocity (the velocity reduction of each stage is 40% to 60%), which improves the foreign matter separation efficiency of the separator.

[0084] The components used in Example 4 that have the same reference numerals as those in Example 1 indicate that they have the same or similar structural features.

[0085] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A foreign object capture device for a delivery pipeline, comprising: The separator body (11) is used to collect foreign matter separated by the separator body. The two ends of the separator body are connected to the conveying pipeline. The feature is that the end pipeline (12) is located below the separator body. The cross-sectional area of ​​the separator body (11) is larger than that of the conveying pipeline. The sudden change in the cross-section of the conveying pipeline causes a local low flow velocity zone, and the foreign matter in the conveying medium is separated and enters the end pipeline (12).

2. The foreign object capture device for the conveying pipeline according to claim 1, characterized in that, The separator body (11) is composed of a lower reducing pipe (1122), a separator speed reducing pipe (111), and an upper reducing pipe (1121) connected in sequence, with the middle part of the separator body (11) being the separator speed reducing pipe (111).

3. The foreign object capture device for the conveying pipeline according to claim 1, characterized in that, The end pipe (12) has a removable blind plate (121) at the bottom for cleaning the end pipe (12) to collect accumulated foreign objects.

4. The foreign object capture device for the conveying pipeline according to claim 2, characterized in that, The diameter of the separator deceleration pipe (111) is 2 to 5 times the diameter of the delivery pipeline.

5. The foreign object capture device for the conveying pipeline according to claim 2, characterized in that, The separator deceleration tube (111) is 1 to 2 meters long.

6. The foreign object capture device for the conveying pipeline according to claim 2, characterized in that, The lower reducing pipe (1122) has a hand hole (114) on its side, which is sealed with a detachable hand hole blind plate (1141) for cleaning foreign objects inside the separator body (11).

7. The foreign object capture device for the conveying pipeline according to claim 2, characterized in that, The separator body (11) has an upper interface and a lower interface at both ends that can be connected to the delivery pipeline, respectively.

8. The foreign object capture device for the conveying pipeline according to claim 7, characterized in that, The upper interface is connected to the bottom of the upper conveying pipeline via an upper flange (1131) or an upper clamp (1133), and the lower interface is connected to the top of the horizontal bend of the lower conveying pipeline via a lower flange (1132) or a lower clamp (1134).

9. The foreign object capture device for the conveying pipeline according to claim 2, characterized in that, The separator deceleration tube (111) has a spiral guide plate (115) arranged circumferentially at 30-45 degrees on its inner wall to improve the foreign matter separation efficiency.

10. The foreign object capture device for the conveying pipeline according to claim 2, characterized in that, The separator deceleration tube (111) is a stepped deceleration tube, which is composed of multiple deceleration tubes with gradually increasing diameters connected together. Through the step-like attenuation of the flow velocity in the interstage deceleration tubes, a velocity gradient field is formed.

11. The foreign object capture device for a conveying pipeline according to claim 10, characterized in that, The diameter ratio of two adjacent sections of the stepped speed-reducing tube is 1.2 to 1.5.

Images