Tube nest cleaning device

Abstract

The utility model discloses a tube nest cleaning device which comprises a brush tube with a ventilation cavity and a brush body connected to the first end of the brush tube. The first end and the second end of the brush pipe are communicated through the ventilation cavity, and the second end of the brush pipe is suitable for being connected with an external air source; at least one air outlet hole is formed in the portion, close to the first end, of the brush pipe, a spiral brush head is arranged on the peripheral wall of the brush body, and the air outlet hole and the brush head have the same rotating direction. The outer diameter of the brush head is not smaller than that of the brush pipe, and the first end of the brush pipe and the brush body are suitable for extending into an inner cavity of the tube nest. By means of pre-cleaning of the brush head, powder attached to the inner wall of the tube nest is brushed to be loose, gas conveyed from the outside is synchronously pressed into an inner cavity of the tube nest through the gas outlet holes, high-pressure gas flow passes through a spiral channel formed by the spiral brush head and the inner wall of the tube nest, powder in the tube nest is fully blown out, and purging of the inner cavity of the tube nest is achieved. The process is efficient, high in quality, safe and environmentally friendly, and the cost can be effectively controlled.

Description

Technical Field

[0001] The utility model belongs to the technical field of cleaning devices, and in particular relates to a tube array cleaning device. Background Art

[0002] Formaldehyde is one of the important raw materials in the organic chemical industry and is widely used in the wood industry, textile industry, anti-corrosion solutions, resins, polymer materials and other industries. There are currently two main processes for the production of formaldehyde: the silver method and the iron-molybdenum method. Compared with the silver method, the iron-molybdenum method has high conversion rate and catalyst activity, mild operating conditions, safety and environmental protection, long catalyst operation time, low methanol content in the product, and stable product concentration. Therefore, the iron-molybdenum method has gradually replaced the traditional silver method in China.

[0003] In the iron-molybdenum formaldehyde production process, after the formaldehyde reactor is put into operation for a long time, the activity of the catalyst will decrease, and as the temperature rises and the gas pressure increases, severe pulverization will occur. At this time, catalyst powder will adhere to the reactor tubes. When unloading the catalyst, due to the 1-2mm gap between the suction gun and the reactor tubes, some catalyst powder or agglomerated powder will remain on the inner wall of the tubes, resulting in the catalyst being unable to be unloaded cleanly, thereby affecting the re-loading amount of the catalyst, which directly leads to a decrease in the heat transfer efficiency of the reactor, an increase in hot spots, and an increase in the content of by-product CO. Therefore, it is very necessary to clean the inner wall of the reactor tubes every time the catalyst is replaced. At present, the mainstream cleaning methods are:

[0004] 1. Use a 5-10cm steel wire brush to clean the reactor tubes, and then use a vacuum pump to suck out the powder that falls off the tubes, so as to clean the catalyst powder attached to the tube walls;

[0005] Second, use water washing and use a high-pressure water gun to clean each tube separately to remove the catalyst powder attached to the tube wall.

[0006] The above two methods have certain effects and can improve the heat transfer effect, but they also have defects:

[0007] 1. Use a wire brush to clean the catalyst tubes. A large amount of powder is attached to the tubes, which is not easy to fall off, making it difficult to clean thoroughly, and the process is complicated and time-consuming.

[0008] 2. When water washing is used, the cleaning is not thorough when the water pressure is low, and the reactor tubes are severely damaged when the water pressure is high. There is a risk of tube rupture, and the water pressure during cleaning is difficult to control. In addition, after the equipment is cleaned, it is necessary to reinstall the HTF (high temperature box furnace) for heating to remove moisture. The water removal measures are complicated and costly, and the iron-molybdenum catalyst will be poisoned when it comes into contact with water. Therefore, this method has high labor intensity, high investment cost, and it is difficult to guarantee the cleaning quality. At the same time, there are safety risks. Utility Model Content

[0009] In order to solve the above-mentioned problems, according to one aspect of the utility model, a tube array cleaning device is provided, comprising a brush tube with a ventilation cavity and a brush body connected to the first end of the brush tube; the first end of the brush tube is connected to the second end thereof through the ventilation cavity, and the second end of the brush tube is suitable for being connected to an external air source; the brush tube is provided with at least one air outlet near its first end, the outer peripheral wall of the brush body has a spiral brush head, and the air outlet and the brush head have the same rotation direction; the outer diameter of the brush head is not less than the outer diameter of the brush tube, and the first end of the brush tube and the brush body are suitable for extending into the internal cavity of the tube array.

[0010] The tube cleaning device of the utility model has the beneficial effect that when the tube cleaning operation is required, the brush head is inserted into the internal cavity of the tube to clean the catalyst powder on the inner wall of the tube back and forth to loosen the adhesion of the powder and complete the pre-cleaning; at the same time, the second end of the brush tube is connected to the external gas source, and the gas introduced enters from the second end of the brush tube, and then passes through the air outlet arranged near the first end of the brush tube, and is pressed into the interior of the tube to enhance the air pressure. Finally, the high-pressure flowing gas passes through the spiral channel formed by the spiral brush head and the inner wall of the tube to achieve the purge of the internal cavity of the tube. By setting a spiral brush head, and the air outlet and the brush head have the same rotation direction, the gas flows spirally inside the tube, and the powder in the tube can be fully purged out. In this way, the mechanical pre-cleaning of the brush head and the synchronous spiral purge of the gas are used together to achieve efficient, high-quality, safe and environmentally friendly completion of the cleaning of the tube, and the cost can be effectively controlled.

[0011] In some embodiments, the brush tube is provided with a plurality of air outlets near its first end, and the air outlets are evenly distributed on the brush tube. Thus, the evenly arranged air outlets can evenly introduce the purge air into the inner cavity of the array tube, and the dispersed gas can evenly purge the powder from the array tube.

[0012] In some embodiments, the brush tube includes a transverse tube body and a vertical tube body connected to the transverse tube body, the second end of the brush tube is formed at the outer port of the transverse tube body, and the first end of the brush tube is formed at the outer port of the vertical tube body. Thus, the arrangement of the transverse tube body facilitates the connection of an external gas source, and the arrangement of the vertical tube body facilitates the catalyst powder cleaned in the tube array to fall outward under the action of gravity, making the cleaning work more efficient.

[0013] In some embodiments, the middle of the transverse tube portion vertically extends outward to form a vertical tube portion, one end of the transverse tube portion forms the second end of the brush tube, and the other end of the transverse tube portion forms the third end of the brush tube; the third end of the brush tube is provided with an end cap for sealing the third end. Therefore, by providing the third end, opening the end cap facilitates cleaning the inside of the brush tube.

[0014] In some embodiments, the outer diameter of the brush head is greater than the outer diameter of the brush tube.

[0015] In some embodiments, the outer diameter of the brush head is 1-2 mm larger than the outer diameter of the brush tube. Thus, the outer diameter of the brush head is set larger than the brush tube, which facilitates the brush head to enter the inner cavity of the array tube and facilitates the cleaning of the inner peripheral wall of the array tube by the brush head.

[0016] In some embodiments, the brush body is detachably connected to the first end of the brush tube, thereby facilitating the removal and replacement of the brush head of the brush body.

[0017] In some embodiments, the brush body is connected to the first end of the brush tube by a threaded connection, so that the threaded connection makes it convenient and easy to disassemble and replace the brush head of the brush body.

[0018] In some embodiments, the brush head and the air outlet are both in the shape of a right-handed spiral; the length of the brush body is 80-100 mm; the brush head is made of steel wire to form a steel wire brush head. As a result, the brush head and the air outlet are both in the shape of a right-handed spiral with the same direction, which is conducive to forming a spiral flow path for the gas pressed into the tube array. By adapting the brush body to the length of the catalyst tube array, the inner circumferential wall of the tube array can be cleaned back and forth efficiently, and the steel wire brush has a good cleaning effect.

[0019] In some embodiments, the second end of the brush tube is provided with an air source valve for opening or closing the ventilation cavity, thereby controlling the start and stop of gas injection through the air source valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of a tube cleaning device according to an embodiment of the utility model;

[0021] Figure 2 for Figure 1 The state diagram of the middle tube cleaning device when cleaning the reactor tubes;

[0022] Figure 3 for Figure 2 Sectional view along AA direction.

[0023] In the figure:

[0024] 10. Brush tube; 11. First end; 12. Second end; 13. Third end; 14. Ventilation cavity; 15. Air outlet; 16. Horizontal tube body; 17. Vertical tube body; 18. End cover; 20. Brush body; 21. Brush head; 30. Air source valve; 100. Tube array; 200. External air source; H. Air flow rotation direction. DETAILED DESCRIPTION

[0025] The utility model is further described in detail below in conjunction with the accompanying drawings.

[0026] In the description of the present utility model, it should be understood that the terms "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present utility model. In addition, the terms "first", "second", etc. are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. The terms "include", "comprise", "have" and their variations all mean "including but not limited to", unless otherwise specifically emphasized.

[0027] Figure 1 A cleaning device for a tube array 100 according to an embodiment of the utility model is schematically shown, the device comprising a brush tube 10 having a ventilation cavity 14 and a brush body 20 connected to a first end 11 of the brush tube 10; the first end 11 of the brush tube 10 is in communication with a second end 12 thereof via the ventilation cavity 14, and the second end 12 of the brush tube 10 is suitable for being connected to an external air source; the brush tube 10 is provided with at least one air outlet 15 near its first end 11, the outer peripheral wall of the brush body 20 has a spiral brush head 21, and the air outlet 15 and the brush head 21 have the same rotation direction; the outer diameter of the brush head 21 is not less than the outer diameter of the brush tube 10, and the first end 11 of the brush tube 10 and the brush body 20 are suitable for extending into the internal cavity of the tube array 100.

[0028] The cleaning device for the tube array 100 of the above embodiment is used for cleaning the reactor tube array 100 in the formaldehyde process, see Figure 2As shown, the second end 12 of the brush tube 10 is provided with an air source valve 30 for opening or closing the ventilation cavity 14. When it is necessary to clean the tube array 100, the upper and lower manholes of the formaldehyde reactor are opened, and the bottom manhole is forced to evacuate to ensure a slight negative pressure on the upper part of the tube array 100. The brush head 21 is inserted into the internal cavity of the tube array 100 to clean the catalyst powder on the inner wall of the tube array 100 back and forth to loosen the adhesion of the powder and complete the pre-cleaning; at the same time, the air source valve 30 is opened, the second end 12 of the brush tube 10 is connected to the external air source 200, and the gas introduced is discharged from the second end 12 of the brush tube 10 The gas enters the tube 100 through the outlet hole 15 arranged near the first end 11 of the brush tube 10, and then is pressed into the interior of the tube 100 to enhance the air pressure. Finally, the high-speed flowing gas passes through the spiral channel formed by the spiral brush head 21 and the inner wall of the tube 100, and the flow path is the air flow rotation direction H, so as to achieve the purge of the internal cavity of the tube 100. By providing the spiral brush head 21, and the outlet hole 15 and the brush head 21 have the same rotation direction, the gas flows spirally inside the tube 100, and the powder in the tube 100 can be fully purged out. In this way, the mechanical pre-cleaning of the brush head 21 and the synchronous spiral purge of the gas are used together to achieve the cleaning work of the tube 100 in an efficient, high-quality, safe and environmentally friendly manner. In this way, the catalyst powder attached to the formaldehyde reactor tubes 100 is removed, the loading amount of the catalyst in the formaldehyde reactor is increased, the heat transfer efficiency is improved, the hot spot temperature of the formaldehyde reactor is reduced, the generation of byproduct CO is reduced, the formaldehyde output is increased, and energy saving and consumption reduction of the device are achieved. After the cleaning work is completed, the gas source valve 30 is closed to disconnect the gas source.

[0029] In this embodiment, the brush tube 10 is provided with a plurality of air outlet holes 15 near the first end 11 thereof, and the air outlet holes 15 are evenly distributed on the brush tube 10. Figure 3 As shown, three air outlet holes 15 are evenly arranged along the circumference near the first end 11 of the brush tube 10, and the rotation direction is consistent with the brush head 21. Therefore, through the evenly arranged air outlet holes 15, the purge air can be evenly introduced into the inner cavity of the array tube 100, and the dispersed gas can evenly purge the powder from the array tube 100.

[0030] Specifically, see Figure 1 The brush tube 10 includes a transverse tube body 16 and a vertical tube body 17 connected to the transverse tube body 16, the second end 12 of the brush tube 10 is formed at the outer end of the transverse tube body 16, and the first end 11 of the brush tube 10 is formed at the outer end of the vertical tube body 17. Therefore, the arrangement of the transverse tube body 16 facilitates the connection of an external gas source, and the arrangement of the vertical tube body 17 facilitates the catalyst powder cleaned in the array tube 100 to fall outward under the action of gravity, so that the cleaning work is more efficient.

[0031] The middle part of the transverse tube portion 16 extends vertically outward to form a vertical tube portion 17, one end of the transverse tube portion 16 forms the second end 12 of the brush tube 10, and the other end of the transverse tube portion 16 forms the third end 13 of the brush tube 10. In a preferred embodiment, Figure 1 As shown, the third end 13 of the brush tube 10 is provided with an end cap 18 for sealing the third end 13. Thus, through the arrangement of the third end 13, opening the end cap 18 facilitates cleaning of the interior of the brush tube 10.

[0032] In this embodiment, the outer diameter of the brush head 21 is larger than the outer diameter of the brush tube 10, and the outer diameter of the brush head 21 is larger than the outer diameter of the brush tube 10 by 1-2 mm. Therefore, the outer diameter of the brush head 21 is set larger than the brush tube 10, which facilitates the brush head 21 to enter the inner cavity of the array tube 100 and facilitates the cleaning of the inner peripheral wall of the array tube 100 by the brush head 21.

[0033] Preferably, the brush body 20 is detachably connected to the first end 11 of the brush tube 10. Thus, it is convenient to disassemble and replace the brush head 21 of the brush body 20. Figure 2 As shown, the brush body 20 is connected to the first end 11 of the brush tube 10 by a threaded connection. Therefore, the threaded connection makes it convenient and easy to disassemble and replace the brush head 21 of the brush body 20. In other embodiments, the brush body 20 and the first end 11 of the brush tube 10 can also be connected by a groove, a buckle, or other mechanical connection forms that are easy to disassemble.

[0034] In this example, if Figure 2 As shown, the brush head 21 and the air outlet 15 are both in a right-handed spiral shape; the length of the brush body 20 is 80-100 mm; the brush head 21 is made of steel wire to form a steel wire brush head 21. Therefore, the brush head 21 and the air outlet 15 are both in a right-handed spiral shape with the same direction, which is conducive to forming a spiral flow path for the gas pressed into the tube array 100. By adapting the brush body 20 of the length of the tube array 100 of the formaldehyde reactor, the inner circumferential wall of the tube array 100 can be cleaned back and forth efficiently, and the steel wire brush has a good cleaning effect.

[0035] The tube 100 cleaning device provided in the embodiment of the utility model is applicable to the cleaning of the reactor tube 100 of the formaldehyde process, and is also applicable to the cleaning of the tube 100 of other related types of heat exchangers.

[0036] The cleaning device for the tube array 100 of the utility model loosens the powder attached to the inner wall of the tube array 100 by pre-cleaning with the brush head 21, and simultaneously presses the gas transported from the outside into the inner cavity of the tube array 100 through the air outlet 15. The high-pressure airflow passes through the spiral channel formed by the spiral brush head 21 and the inner wall of the tube array 100, and the powder in the tube array 100 is fully blown out, so that the internal cavity of the tube array 100 is purged. This process is efficient, high-quality, safe and environmentally friendly, and can effectively control costs.

[0037] The above are only some embodiments of the present invention. For those skilled in the art, several modifications and improvements can be made without departing from the inventive concept of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application belong to the scope of protection of the present invention.

Claims

1. A tube cleaning device, characterized in that: include: A brush tube having a ventilation cavity and a brush body connected to a first end of the brush tube; The first end of the brush tube is connected to the second end thereof through the ventilation cavity, and the second end of the brush tube is suitable for being connected to an external air source; The brush tube is provided with at least one air outlet near its first end, the outer peripheral wall of the brush body has a spiral brush head, and the air outlet and the brush head have the same rotation direction; the outer diameter of the brush head is not less than the outer diameter of the brush tube, and the first end of the brush tube and the brush body are suitable for extending into the internal cavity of the array tube.

2. The tube cleaning device according to claim 1, characterized in that: The brush tube is provided with a plurality of air outlet holes near the first end thereof, and the air outlet holes are evenly distributed on the brush tube.

3. The tube cleaning device according to claim 1, characterized in that: The brush tube includes a transverse tube portion and a vertical tube portion connected to the transverse tube portion, the second end of the brush tube is formed at an outer port of the transverse tube portion, and the first end of the brush tube is formed at an outer port of the vertical tube portion.

4. The tube cleaning device according to claim 3, characterized in that: The middle part of the transverse tube body portion extends vertically outward to form the vertical tube body portion, one end of the transverse tube body portion forms the second end of the brush tube, and the other end of the transverse tube body portion forms the third end of the brush tube; the third end of the brush tube is provided with an end cover for sealing the third end.

5. The tube cleaning device according to any one of claims 1 to 4, characterized in that: The outer diameter of the brush head is greater than the outer diameter of the brush tube.

6. The tube cleaning device according to claim 5, characterized in that: The outer diameter of the brush head is greater than the outer diameter of the brush tube in a range of 1-2 mm.

7. The tube cleaning device according to any one of claims 1 to 4, characterized in that: The brush body is detachably connected to the first end of the brush tube.

8. The tube cleaning device according to claim 7, characterized in that: The brush body is connected to the first end of the brush tube by threaded connection.

9. The tube cleaning device according to claim 1, characterized in that: The brush head and the air outlet are both in the shape of a right-hand spiral; the length of the brush body is 80-100 mm; the brush head is made of steel wire to form a steel wire brush head.

10. The tube cleaning device according to claim 1, characterized in that: The second end of the brush tube is provided with an air source valve for opening or closing the ventilation cavity.

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