A living monomer polymerization inhibitor supply device

Abstract

The present application relates to the technical field of high polymer material, in particular to a kind of inhibitor supply device of active monomer, including inhibitor storage tank, inhibitor conveying pipe, metering pump and connecting pipe fitting;The end of connecting pipe fitting is towards downstream direction, the flow guide tube is connected in pipe body, there is flow dead zone in the right side of flow guide tube in pipe body, the flow dead zone is coaxial with pipe body, the flow dead zone is communicated with inhibitor conveying pipe, the other end of inhibitor conveying pipe is communicated with inhibitor storage tank, and metering pump is arranged on inhibitor conveying pipe;The present application can add inhibitor in pipeline, prevent pipeline from scaling, ensure the smooth progress of production, extend maintenance cycle, while the addition amount of inhibitor in pipeline is small, does not affect the normal operation of other processes, does not affect storage and transportation process and use process.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, and more specifically to a polymerization inhibitor supply device for active monomers. Background Technology

[0002] Vinyl resins or vinyl monomers may undergo self-polymerization during storage, transportation, separation, and refining under the influence of impurities such as heat, light, or peroxides. Examples include unsaturated polyester resins, dicyclopentadiene (DCPD), or acrylate monomers. To prevent self-polymerization, polymerization inhibitors need to be added to the raw material storage tank to stop the polymerization.

[0003] Patent application number 201721114048.0 discloses a polymerization inhibitor addition device, including a feeding section directly connected to a raw material storage tank, an addition section for adding volatile polymerization inhibitors, and a connecting section for connecting the addition section and the feeding section. The addition section has a storage cavity for storing volatile polymerization inhibitors at a position below the connecting section. The above structure can be used to supply polymerization inhibitors, but it cannot add polymerization inhibitors into the pipeline to prevent scaling.

[0004] Adding polymerization inhibitors during storage is relatively easy, but during production and refining, materials can easily polymerize and adhere to pipelines, such as at the vapor outlet of distillation columns, bends in various monomer transport pipelines, and instrument valve locations. When scale forms in these pipelines due to material polymerization, it can damage instruments and valves. For example, in the production of dicyclopentadiene, dicyclopentadiene is prone to polymerization. The polymerized polydicyclopentadiene adheres to the pipeline, easily damaging auxiliary devices such as shut-off valves and magnetic level gauges. Furthermore, once scale forms on the inner wall of the pipeline due to polymerization, it can quickly become blocked, rendering the pipeline unusable.

[0005] Therefore, there is an urgent need for a polymer inhibitor supply device for active monomers to add polymer inhibitors to pipelines and prevent scaling. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a polymerization inhibitor supply device for active monomers. The purpose is to add polymerization inhibitors to pipelines to prevent scaling, ensure smooth production, and extend maintenance cycles. Furthermore, this invention also features the advantages of requiring only a small amount of polymerization inhibitor, not affecting the normal operation of other processes, and not impacting storage, transportation, or usage.

[0007] To achieve the above objectives, the technical solution used in this invention is as follows:

[0008] A polymerization inhibitor supply device for an active monomer includes a polymerization inhibitor storage tank, a polymerization inhibitor delivery pipe, a metering pump, and connecting fittings.

[0009] The connecting pipe includes a pipe body and a flow guide tube. The left end of the pipe body faces the upstream direction of the incoming flow and the right end faces the downstream direction. The flow guide tube is connected to the pipe body. There is a flow dead zone in the pipe body on the right side of the flow guide tube. The flow dead zone is coaxial with the pipe body. The flow dead zone is connected to the polymerization inhibitor delivery pipe. The other end of the polymerization inhibitor delivery pipe is connected to the polymerization inhibitor storage tank. A metering pump is installed on the polymerization inhibitor delivery pipe.

[0010] The guide tube forms a flow guiding state within the pipe body. After the flow cross-section is reduced, a flow dead zone is formed on the right side of the guide tube. The fluid in this flow dead zone basically does not participate in the flow of the mainstream area, but only circulates within the flow dead zone. After the polymerization inhibitor delivery pipe connects to the flow dead zone, the polymerization inhibitor is injected into the flow dead zone to prevent the fluid in this flow dead zone from polymerizing due to prolonged stagnation. Furthermore, due to the addition of the polymerization inhibitor, the fluid volume in the flow dead zone increases. At the interface between the flow dead zone and the mainstream area, some of the material in the flow dead zone will be carried away by the mainstream area, and the carried-away material flows along the pipe wall, forming a liquid film with a polymerization inhibitor effect in the laminar flow within the inner wall of the pipe. Therefore, this invention forms a polymerization inhibitor effect on the inner wall of the pipe, adding the polymerization inhibitor only to the inner wall of the pipe. Compared with the prior art of adding the polymerization inhibitor to the entire pipe, this invention uses a lower amount of polymerization inhibitor, does not affect the amount added in subsequent processes, and does not accumulate significantly in the production equipment, thus not affecting the production process.

[0011] Furthermore, the left side of the inner wall of the guide tube is conical, the inner diameter of the right side is smaller than the inner diameter of the tube body, and the inner diameter of the left end of the guide tube is the same as the inner diameter of the tube body.

[0012] The fluid flow cross-section inside the pipe gradually decreases from left to right to the inner diameter of the guide tube, creating a coaxial flow dead zone inside the pipe and increasing the flow velocity inside the guide tube, thereby increasing the Reynolds number in the mainstream region and ensuring the stability of the flow dead zone.

[0013] Furthermore, the polymerization inhibitor delivery pipe is connected to the flow dead zone via a polymerization inhibitor storage chamber, which is located inside the guide tube. The polymerization inhibitor storage chamber is connected to the flow dead zone via a microchannel, which is a channel with a small flow cross-section.

[0014] Microchannels allow the polymerization inhibitor to pass through when the metering pump is working and restrict its passage when the metering pump is not working, thus preventing excessive leakage of the polymerization inhibitor when the production system is shut down.

[0015] Furthermore, the guide tube includes a guide element and a separator. The guide element is fixedly connected to the inner wall of the tube. The right side wall of the guide element is recessed inside the guide element. The separator is located in the opening of the recess of the guide element. There is a cavity between the separator and the guide element. The cavity between the guide element and the separator constitutes a polymerization inhibitor storage cavity. The separator and the guide element rotate relative to each other. The separator has micropores, which constitute microchannels.

[0016] The structure of the guide tube is specifically disclosed. The separator rotates relative to the guide tube, so that the polymerization inhibitor flowing out through the micropores forms a uniform distribution, ensuring that the liquid film containing the polymerization inhibitor on the inner wall of the pipeline is uniform and consistent.

[0017] Furthermore, the inner diameter of the micropore is 0.2mm-0.5mm, and the length of the micropore is greater than 1cm.

[0018] Furthermore, the number of micropores is multiple, and the multiple micropores are distributed in a circumferential array on the separator.

[0019] Furthermore, the separator is provided with mixing blades located on the side of the micropores, and the mixing blades are located within the flow dead zone.

[0020] The mixing blades promote the disturbance of the flow dead zone when the separator rotates, further ensuring the uniformity of the polymerization inhibitor.

[0021] Furthermore, the pipe body is composed of a left pipe and a right pipe, which are connected by a flange. The separator is located between the left pipe and the right pipe, and the outer edge of the separator is provided with teeth, which mesh with the gear at the output end of the reduction motor outside the pipe body.

[0022] When the Reynolds number of the fluid inside the pipe changes, the size of the flow dead zone also changes, which can lead to drastic changes in the content of polymerization inhibitor in the fluid along the inner wall of the pipe.

[0023] Furthermore, the separator has a protrusion facing the flow dead zone, the micropores penetrate the protrusion, and the mixing blades are located on the surface of the protrusion.

[0024] The protrusion occupies part of the flow dead zone, so that although the flow dead zone exists, it occupies a small space. This ensures that the total amount of polymerization inhibitor in the flow dead zone is not large, thus avoiding drastic changes in the content of polymerization inhibitor along the inner wall of the pipe due to changes in the size of the flow dead zone when the flow rate and velocity of the fluid in the pipe fluctuate.

[0025] Furthermore, inspection tubes are provided at both the left and right ends of the tube body, and a sealing element is provided inside the inspection tube. The sealing element is connected inside the inspection tube, and the inner end of the sealing element is on the same circumferential surface as the inner wall of the tube body.

[0026] Inspection tubes are used to inspect the inside of the pipe during maintenance, to check and clean scale on the inner wall of the pipe, and to change the internal shape of the pipe by changing the inner end of the sealing component, thus ensuring the flow of fluid.

[0027] Beneficial effects

[0028] This invention enables the addition of a polymerization inhibitor to pipelines to prevent scaling, ensure smooth production, extend maintenance cycles, and reduce the amount added near the pipe wall in laminar flow compared to existing technologies. This does not affect the normal operation of other processes, nor does it affect storage, transportation, or use.

[0029] The present invention has a polymerization inhibitor storage cavity, which makes the addition of polymerization inhibitor more uniform and also saves more polymerization inhibitor.

[0030] The flow guide and the separator of the present invention together constitute the flow guide cylinder, and the separator and the flow guide rotate relative to each other. The separator is provided with mixing blades, so that the addition of the polymerization inhibitor is more uniform.

[0031] The inspection tube of this invention can be used to inspect, repair, and maintain the internal parts of the invention, and to conveniently clean the internal parts of the invention. Attached Figure Description

[0032] Figure 1 This is a cross-sectional front view of Embodiment 1 of the present invention;

[0033] Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0034] Figure 3 This is a sectional front view of the connecting pipe fitting in Embodiment 2 of the present invention;

[0035] Figure 4 This is a schematic diagram of the structure of the separator in Embodiment 2 of the present invention;

[0036] Figure 5 yes Figure 3 Sectional view along axis AA;

[0037] Figure 6 yes Figure 3 BB-direction sectional view;

[0038] Figure 7 yes Figure 3 Enlarged view of section C;

[0039] Figure 8 This is a sectional front view of the connecting pipe fitting in Embodiment 3 of the present invention.

[0040] The attached diagram is labeled as follows: 1. Inhibitor storage tank; 2. Inhibitor delivery pipe; 3. Metering pump; 4. Connecting fittings; 5. Pipe body; 6. Flow guide tube; 7. Flow dead zone; 8. Flow guide; 9. Separator; 10. Inhibitor storage chamber; 11. Micropore; 12. Mixing blade; 13. Left pipe; 14. Right pipe; 15. Bolt; 16. Spacer sleeve; 17. Shoulder; 18. Sealing strip; 19. Tooth; 20. Gear motor; 21. Gear; 22. Inspection pipe; 23. Sealing element; 24. Protrusion. Detailed Implementation

[0041] This invention is mainly applied to the conveying pipeline in the production process of active monomers, and is connected to the starting end of the pipeline. In order to make the purpose, technical solution and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0042] Example 1:

[0043] like Figure 1 As shown, a polymerization inhibitor supply device for active monomers includes a polymerization inhibitor storage tank 1, a polymerization inhibitor delivery pipe 2, a metering pump 3, and connecting pipe fittings 4.

[0044] The polymerization inhibitor storage tank 1 is connected to the connecting pipe 4 via the polymerization inhibitor delivery pipe 2, and the polymerization inhibitor delivery pipe 2 is equipped with a metering pump 3.

[0045] The connecting pipe 4 includes a pipe body 5 and a guide tube 6. The left end of the pipe body 5 faces the upstream direction of the incoming flow and the right end faces the downstream direction. That is, the fluid enters from the left end of the pipe body 5 and flows out from the right end. The guide tube 6 is connected inside the pipe body 5. The guide tube 6 is a plate-shaped structure with a central hole or a tapered tube structure with a gradually narrowing inner diameter. There is a flow dead zone 7 inside the pipe body 5 on the right side of the guide tube 6. The flow dead zone 7 is caused by the sudden expansion of the flow cross section. The flow dead zone 7 is coaxial with the pipe body 5 and is connected to the polymerization inhibitor delivery pipe 2.

[0046] There are many options for the flow guide tube 6. If the flow cross section inside the tube body 5 at the left end of the flow guide tube 6 changes abruptly, a flow dead zone will also appear on the left side of the flow guide tube 6. This flow dead zone will affect the effect of the present invention. Therefore, it is necessary to avoid the flow dead zone appearing on the left side of the flow guide tube 6.

[0047] In this embodiment: the left side of the inner wall of the guide tube 6 is conical and the right side is straight. The inner diameter of the right side of the guide tube 6 is smaller than the inner diameter of the tube body 5, and the inner diameter of the left end of the guide tube 6 is the same as the inner diameter of the tube body 5.

[0048] Figure 1 The area enclosed by the dotted line portion, the right end of the guide tube 6, and the inner wall of the tube body 5 is the flow dead zone 7.

[0049] Example 2:

[0050] like Figure 2 and Figure 3 As shown, a polymerization inhibitor supply device for active monomers includes a polymerization inhibitor storage tank 1, a polymerization inhibitor delivery pipe 2, a metering pump 3, and connecting pipe fittings 4.

[0051] The polymerization inhibitor storage tank 1 is connected to the connecting pipe 4 via the polymerization inhibitor delivery pipe 2, and the polymerization inhibitor delivery pipe 2 is equipped with a metering pump 3.

[0052] The connecting pipe 4 includes a pipe body 5 and a guide tube 6. Fluid enters from the left end of the pipe body 5 and flows out from the right end. The guide tube 6 is connected inside the pipe body 5. The guide tube 6 is a tapered tube structure with a gradually narrowing inner diameter. There is a flow dead zone 7 inside the pipe body 5 on the right side of the guide tube 6. The flow dead zone 7 is coaxial with the pipe body 5 and is connected to the polymerization inhibitor delivery pipe 2.

[0053] like Figure 3 As shown, the guide tube 6 includes a guide member 8 and a separator 9. The guide member 8 is fixedly connected to the inner wall of the tube body 5. The right side wall of the guide member 8 is recessed inside the guide member 8. The separator 9 is located inside the opening of the recess in the guide member 8. Figure 4 As shown, the separator 9 has a disc-shaped structure, and there is a cavity between the separator 9 and the flow guide 8. This cavity is the polymerization inhibitor storage cavity 10. The polymerization inhibitor delivery pipe 2 and the flow dead zone 7 are connected through the polymerization inhibitor storage cavity 10. The separator 9 and the flow guide 8 rotate relative to each other. The separator 9 has micropores 11. There are multiple micropores 11, which are distributed in a circumferential array on the separator 9. The inner diameter of the micropores 11 is 0.2mm-0.5mm, and the length of the micropores 11 is greater than 1cm. The micropores 11 form microchannels, which enable the polymerization inhibitor to be distributed more evenly. The polymerization inhibitor storage cavity 10 and the flow dead zone 7 are connected through the micropores 11.

[0054] Microchannels are pores with a small cross-section, including but not limited to small-diameter holes, annular slits between the right end of the guide tube 6 and the inner wall of the tube body 5, etc.

[0055] Microchannels allow the polymer inhibitor to pass through when the metering pump is working and restrict its passage when the metering pump is not working, thus preventing excessive leakage of the polymer inhibitor when the production system is shut down.

[0056] The separator 9 is provided with mixing blades 12 located on the side of the micro-holes 11. The mixing blades 12 are located in the flow dead zone 7 and are used to further turbulent the flow dead zone 7.

[0057] like Figure 3 As shown, the pipe body 5 consists of a left pipe 13 and a right pipe 14, which are connected by flanges. A spacer 9 is located between the left pipe 13 and the right pipe 14, and slides in contact with the flanges of the left pipe 13 and the right pipe 14 respectively. In order to allow the spacer 9 to be located between the two flanges and to slide, a spacer sleeve 16 is fitted on the shank of the bolt 15 connecting the flanges of the left pipe 13 and the right pipe 14. The left and right ends of the spacer sleeve 16 abut against the surfaces of the two flanges respectively. Figure 4 As shown, the left and right sides of the separator 9 are provided with shoulders 17 that slide in contact with the inner walls of the left tube 13 and the right tube 14. Each shoulder 17 has a sealing groove, and a sealing strip 18 is provided within the sealing groove. Figure 6As shown, the outer edge of the separator 9 is provided with teeth 19. The diameter of the circle where the tip of the teeth 19 is located is smaller than the diameter of the circle where the bolt 15 is located. The teeth 19 mesh with the gear 21 at the output end of the geared motor 20 outside the tube body 5. The gear 21 at the output end of the geared motor 20 is located between two adjacent bolts 15.

[0058] like Figure 2 , Figure 3 and Figure 5 As shown, the left and right ends of the tube body 5 are provided with inspection tubes 22, and the inspection tubes 22 are provided with sealing members 23. The sealing members 23 are connected inside the inspection tubes 22, and the inner end of the sealing members 23 is on the same circumferential surface as the inner wall of the tube body 5.

[0059] Example 3:

[0060] This embodiment is basically the same as Embodiment 2, and the similarities will not be repeated. The differences are as follows:

[0061] like Figure 8 As shown, when the Reynolds number of the fluid inside pipe 5 changes, the size of the flow dead zone 7 changes accordingly. This leads to drastic changes in the content of the polymerization inhibitor in the fluid along the inner wall of the pipe, such as... Figure 7 As shown, the separator 9 has a protrusion 24 facing the flow dead zone 7, the micropores penetrate the protrusion, and the mixing blades are located on the surface of the protrusion to reduce the volume of the flow dead zone.

[0062] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Claims

1. A polymerization inhibitor supply device for an active monomer, characterized in that, It includes an inhibitor storage tank (1), an inhibitor delivery pipe (2), a metering pump (3), and connecting pipe fittings (4). The connecting pipe (4) includes a pipe body (5) and a guide tube (6). The left end of the pipe body (5) faces the upstream direction of the incoming flow and the right end faces the downstream direction. The guide tube (6) is connected inside the pipe body (5). There is a flow dead zone (7) inside the pipe body (5) on the right side of the guide tube (6). The flow dead zone (7) is coaxial with the pipe body (5). The flow dead zone (7) is connected to the polymerization inhibitor delivery pipe (2). The other end of the polymerization inhibitor delivery pipe (2) is connected to the polymerization inhibitor storage tank (1). A metering pump (3) is provided on the polymerization inhibitor delivery pipe (2). The inner wall of the guide tube (6) is cone-shaped on the left and the inner diameter of the right side is smaller than that of the tube body (5). The inner diameter of the left end of the guide tube (6) is the same as that of the tube body (5). The polymerization inhibitor delivery pipe (2) is connected to the flow dead zone (7) via the polymerization inhibitor storage chamber (10), which is located inside the guide tube (6). The polymerization inhibitor storage chamber (10) is connected to the flow dead zone (7) via a microchannel. The guide tube (6) includes a guide element (8) and a separator (9). The guide element (8) is fixedly connected to the inner wall of the tube body (5). The right side wall of the guide element (8) is recessed inside the guide element (8). The separator (9) is located in the opening of the recess of the guide element (8). There is a cavity between the separator (9) and the guide element (8). The cavity between the guide element (8) and the separator (9) constitutes a polymerization inhibitor storage cavity (10). The separator (9) rotates relative to the guide element (8). The separator (9) has micropores (11). The micropores (11) constitute a microchannel. The separator (9) is provided with a mixing blade (12) located on the side of the micropore (11), and the mixing blade (12) is located in the flow dead zone (7); The separator (9) has a protrusion (24) facing the flow dead zone (7), the micropore (11) penetrates the protrusion (24), and the mixing blade (12) is located on the surface of the protrusion (24).

2. The polymerization inhibitor supply device for the active monomer according to claim 1, characterized in that, The inner diameter of the micropore (11) is 0.2mm-0.5mm, and the length of the micropore (11) is greater than 1cm.

3. The polymerization inhibitor supply device for the active monomer according to claim 1, characterized in that, The number of micropores (11) is multiple, and the multiple micropores (11) are distributed in a circumferential array on the separator (9).

4. The polymerization inhibitor supply device for the active monomer according to claim 1, characterized in that, The pipe body (5) is composed of a left pipe (13) and a right pipe (14), which are connected by a flange. The separator (9) is located between the left pipe (13) and the right pipe (14). The outer edge of the separator (9) is provided with teeth (19), which mesh with the gear (21) at the output end of the speed reduction motor (20) outside the pipe body (5).

5. The polymerization inhibitor supply device for the active monomer according to claim 1, characterized in that, The left and right ends of the tube body (5) are provided with inspection tubes (22), and the inspection tubes (22) are provided with sealing elements (23). The sealing elements (23) are connected inside the inspection tubes (22), and the inner end of the sealing elements (23) is on the same circumferential surface as the inner wall of the tube body (5).

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