Device for preventing high-temperature thermal stress damage of gas-phase feed port of quench tower

Abstract

The invention relates to the field of chemical production process equipment design, in particular to a high-temperature thermal stress damage prevention device for a gas-phase feed port of a quench tower, which comprises a stress receiving device and a stress absorbing device. The stress receiving device comprises a barrel I and a lining barrel, the barrel I is communicated with the outer end of the lining barrel, a cone shell and a barrel II are sequentially arranged on the outer side of the lining barrel in the direction away from the barrel I, and ceramic fibers are filled among the cone shell, the barrel II and the lining barrel; the inner end of the cylinder II is fixed on an equipment body of the quench tower; the stress absorption device comprises an outer sleeve and a connecting pipe, the connecting pipe is communicated with an internal pipeline of the quench tower and is inserted into the outer sleeve, the outer side of the inner end of the bushing is fixed on the inner wall of the outer sleeve, and a gap is formed between the inner end of the bushing and the end part of the connecting pipe.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of chemical production process equipment design, in particular to a device for preventing high-temperature thermal stress damage of a gas-phase feed inlet of a quench tower. BACKGROUND

[0002] In the field of chemical plant production, the reactor product gas phase part is cooled by a reactor discharge cooler (or other condensing, cooling or similar device or equipment) and flows to a quench tower and the like. However, due to process or human reasons, the discharge cooler in the process flow has a risk of failure. If the discharge cooler fails, the reactor product gas phase will flow to the gas-phase feed inlet of the quench tower at a very high temperature before the safety interlock device acts, causing local high temperature and then forming local thermal stress, causing damage to the feed inlet or internal parts of the equipment, and further causing production safety hazards.

[0003] To prevent the discharge cooler or similar device or component in the process from failing, the cylinder is often thickened or the wall thickness of the gas-phase feed inlet connecting pipe is increased to prevent high-temperature damage. However, the thermal stress damage caused by local high temperature often has uncertainty in position and size, and the method of thickening the cylinder or increasing the wall thickness of the gas-phase feed inlet connecting pipe cannot fundamentally prevent equipment failure and ensure safe operation of the equipment, bringing safety hazards to chemical production. For example, existing research discloses a method of only increasing the cylinder thickness to cope with local thermal stress. If the cylinder is too thick, it will cause waste of materials and increase investment costs. If the increased cylinder thickness does not meet the requirements of thermal stress, the equipment will still be damaged due to local thermal stress. For another example, existing research discloses a method of only increasing the wall thickness of the gas-phase feed inlet connecting pipe to cope with local thermal stress. Simply increasing the wall thickness of the connecting pipe will result in a large difference in wall thickness between the connecting pipe and the shell, causing uneven temperature gradient distribution of the connecting pipe and the shell, increasing the thermal stress of the connecting pipe and the shell, and being unable to fundamentally and effectively solve the problem of excessive local thermal stress, achieving the intrinsic safety of the equipment. SUMMARY

[0004] The present application provides a device for preventing high-temperature thermal stress damage of a gas-phase feed inlet of a quench tower, which overcomes the problem that the method of only increasing the wall thickness of the equipment or only increasing the wall thickness of the gas-phase feed inlet connecting pipe cannot solve the problem of excessive local thermal stress, and avoids the risk of failure of the equipment body or internal parts due to local high temperature generating thermal stress.

[0005] The present application is achieved by the following technical solutions: A device for preventing high-temperature thermal stress damage of a gas-phase feed inlet of a quench tower, comprising a stress receiving device and a stress absorbing device. The stress receiving device comprises a cylinder I and a lining cylinder, the cylinder I is communicated with the outer end of the lining cylinder, the outer side of the lining cylinder is sequentially provided with a cone shell and a cylinder II in the direction away from the cylinder I, the cone shell, the cylinder II and the lining cylinder are filled with ceramic fiber; the inner end of the cylinder II is fixed on the equipment body of the quenching tower; The stress receiving device comprises an outer sleeve and a connecting pipe, the connecting pipe is communicated with the internal pipeline of the quenching tower, the connecting pipe is inserted into the outer sleeve, the inner end of the lining cylinder is fixed on the inner wall of the outer sleeve, and the inner end of the lining cylinder has a gap with the end of the connecting pipe.

[0006] Further, the inner end of the cylinder II is welded on the outer side of the annular cover plate, and the edge of the annular cover plate is welded on the equipment body of the quenching tower; The ceramic fiber is filled in the cavity formed by the cone shell, the cylinder II, the annular cover plate and the lining cylinder.

[0007] Further, the outer side of the annular cover plate is provided with a reinforcing ring.

[0008] Further, the cylinder I, the cone shell and the cylinder II are all composite plate structures, the composite plate structure comprises a base layer, the base layer is a non-alloy steel structure, the base layer is provided with a cladding layer, the cladding layer is a high-alloy steel structure, and the lining cylinder is a high-alloy steel structure.

[0009] Further, the inner end of the lining cylinder is welded on the inner wall of the outer sleeve, and the inner end of the lining cylinder has a gap with the end of the connecting pipe.

[0010] Further, the gap is 2-5 mm.

[0011] The beneficial effects obtained by the present application compared with the prior art are as follows: 1. The device is mainly divided into a stress receiving device and a stress absorbing device: the stress receiving device is connected with the external pipeline and is the direct receiver of the thermal stress generated by high temperature; the stress absorbing device is arranged between the stress receiving device and the internal part of the equipment and is used for absorbing the thermal stress generated by high temperature to prevent stress damage to the internal part and further cause equipment failure; The stress receiving device changes the heat stress receiving path into two paths: one path is transmitted to the equipment body along the cylinder I, the cone shell and the cylinder II, and the path only bears part of the pipeline thrust generated by thermal stress; the other path is transmitted along the cylinder I, the lining cylinder and the outer sleeve, and the path bears most of the pipeline thrust (including the pipeline thrust generated by high temperature thermal stress), since the inner end of the lining cylinder has a gap with the end of the connecting pipe and the connecting pipe is inserted into the outer sleeve, force is not transmitted to the internal part of the equipment body, and the equipment body is protected. The two paths jointly bear the high temperature thermal stress, and the stress intensity is reduced; 2. The stress absorbing device and the stress receiving device sleeve mentioned above are connected by a gap, meaning that the internal components of the equipment do not directly bear the high-temperature thermal stress. Compared with the current direct welding connection between the stress absorbing device and the stress receiving device sleeve, this provides a good buffer for the propagation and absorption of high-temperature thermal stress, protects the internal components of the equipment, and has a greater impact on the safe operation of the equipment. 3. By changing the traditional structural form, this invention increases the high-temperature thermal stress receiving path and reduces the intensity of high-temperature thermal stress. Under the same process conditions and the same equipment structure, it improves the safe use of the equipment and avoids the practice of simply increasing the thickness of the equipment wall or the pipe wall to cope with high-temperature thermal stress, which increases costs. Compared with the current method of simply increasing the thickness of the cylinder or the thickness of the gas phase feed port pipe, it saves about 20% of the material cost. Attached Figure Description

[0012] Figure 1 This is a diagram showing the device for preventing high-temperature thermal stress damage at the gas phase feed inlet of the quench tower according to the present invention in the usage state of the equipment body. Figure 2 This is a schematic diagram of the stress receiving device described in this invention; Figure 3 This is a schematic diagram of the stress absorption device described in this invention; In the figure: 1. Stress receiving device, 11. Cylinder I, 12. Conical shell, 13. Cylinder II, 14. Annular cover plate, 15. Liner, 16. Ceramic fiber, 17. Reinforcing ring, 2. Stress absorption device, 21. Outer sleeve, 22. Connecting pipe. Detailed Implementation

[0013] The technical solutions of the embodiments of this application will be clearly and completely described below 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 of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0014] In the description of the invention, it should be understood that the terms "front", "rear", "up", "down", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the invention.

[0015] Due to failure of the cooler or similar device with condensing function in the production system, high-temperature material from the reactor can make the pipeline heat expansion, generate high-temperature thermal stress, and transmit to the core equipment such as the downstream quench tower in the form of pipeline thrust. In order to buffer the pipeline thrust generated by the thermal stress, as shown in Figure 1 , the application discloses a device for preventing high-temperature thermal stress damage of a quench tower gas-phase feed port, mainly including two parts of a stress receiving device 1 and a stress absorbing device 2. The stress receiving device is connected with the external pipeline and is the direct receiver of the thermal stress generated by high temperature; the stress absorbing device is arranged between the stress receiving device and the internal part of the equipment and is used for absorbing the thermal stress generated by high temperature, preventing the stress from damaging the internal part, and further causing equipment failure.

[0016] As shown in Figure 2 , the stress receiving device 1 includes a cylinder I 111, a lining cylinder 15, a conical shell 12, and a cylinder II 113, etc. The cylinder I 111, the conical shell 12, and the cylinder II 113 are all composite plate structures, which include a base layer made of non-alloy steel structure for bearing, and a coating layer made of high-alloy steel structure for preventing internal medium corrosion. The lining cylinder 15 is made of high-alloy steel structure and directly contacts with high-temperature gas phase, and bears part of the pipe opening external load and the thermal stress generated by high-temperature gas phase.

[0017] The cylinder I 111 is connected with the outer end of the lining cylinder 15 in a welding manner. The outer side of the lining cylinder 15 is sequentially provided with the conical shell 12 and the cylinder II 113 in a direction away from the cylinder I 111. The left side inside of the conical shell 12 is welded with the right side outside of the cylinder I 111, and the right side of the conical shell 12 is welded with the left side of the cylinder II 113. The right end of the cylinder II 113 is provided with an annular cover plate 14 between the equipment body of the quench tower. The inner end of the cylinder II 113 is welded on the outer side of the annular cover plate 14. The edge of the annular cover plate 14 is welded on the equipment body of the quench tower. In order to increase the firmness of the annular cover plate, a reinforcing ring 17 is installed on the outer side of the annular cover plate 14. The conical shell 12, the cylinder II 113, the annular cover plate 14, and the lining cylinder 15 form a cavity and are filled with ceramic fiber 16. The ceramic fiber is used for heat insulation and should be compacted and rammed during use. The ceramic fiber heat insulation material should be applicable to a temperature above 1000°C.

[0018] As shown in Figure 3 , the stress absorbing device 2 includes an outer sleeve 21 and a connecting pipe 22, which are made of high-alloy steel. The connecting pipe 22 is connected with the pipeline of the internal part of the quench tower. The connecting pipe 22 is inserted into the outer sleeve 21. The inner end of the lining cylinder 15 is fixed on the inner wall of the outer sleeve 21 in a welding manner. The inner end of the lining cylinder 15 has a gap with the end of the connecting pipe 22.

[0019] The inner end of the liner 15 is welded to the inner wall of the outer sleeve 21. There is a gap of 2-5 mm between the inner end of the liner 15 and the end of the connecting pipe 22 (the gap size is calculated based on process parameters, with the highest temperature setting selected). This gap is used to receive the pipe thrust generated by high temperature and to protect the internal components of the equipment from damage caused by the pipe thrust. The key to its structure is that the outer sleeve is welded to the liner 15 in the aforementioned stress-receiving device, while its connection to the connecting pipe is achieved through friction; welding is not permitted to prevent the device from malfunctioning.

[0020] Example 1 like Figure 1 As shown, based on the aforementioned device for preventing high-temperature thermal stress damage at the gas phase inlet of a quench tower, when applied to equipment with internal components, the stress receiving device is fixed to the outside of the equipment body, and the connecting pipe of the stress absorbing device connects to the internal components of the equipment. The stress receiving device has two stress receiving paths: one path transmits stress to the equipment body along the cylinder I, conical shell, and cylinder II, and this path only bears a portion of the pipeline thrust; the other path transmits stress along cylinder I, liner, and outer sleeve, and this path bears the majority of the pipeline thrust (including the pipeline thrust generated by high-temperature thermal stress). Because there is a gap between the inner end of the liner and the end of the connecting pipe, and the connecting pipe is inserted into the outer sleeve, it does not transmit force to the internal components of the equipment body, thus protecting the equipment body. It does not directly bear high-temperature thermal stress, and compared to the current direct welding connection between the stress absorbing device and the stress receiving device sleeve, it plays a good buffering role in the propagation and absorption of high-temperature thermal stress, protecting the internal components of the equipment. The two paths share the high-temperature thermal stress, reducing the stress intensity.

[0021] Example 2 Based on the above-mentioned device for preventing high-temperature thermal stress damage at the gas phase inlet of the quench tower, when applied to equipment without internal components, stress absorption devices are not required. The stress receiving device is fixed on the outside of the equipment body and has two stress receiving paths. One path transmits stress to the equipment body along the path of cylinder I, conical shell, and cylinder II, and this path only bears part of the pipeline thrust. The other path transmits stress along cylinder I, liner, and outer sleeve, and this path bears most of the pipeline thrust (including the pipeline thrust generated by high-temperature thermal stress), protecting the equipment body and ensuring the equipment operates well.

[0022] Comparative Example 1: A current high-temperature stress-damage prevention device uses the method of thickening the pipe at the gas phase feed inlet to prevent high-temperature damage. The thermal stress generated by the high temperature exceeds the bearing limit of the pipe, causing cracks to appear at the pipe and the equipment to fail.

[0023] Comparative Example 2: A current high-temperature stress-prevention device uses the method of simultaneously increasing the thickness of the equipment wall and the thickness of the pipe at the gas phase feed inlet to prevent high-temperature stress. Due to the single stress transmission path, cracks are generated at the junction of the pipe and the equipment body, causing equipment failure.

Claims

1. A device for preventing high-temperature thermal stress damage at the gas phase feed inlet of a quench tower, characterized in that, It includes a stress receiving device (1) and a stress absorbing device (2); The stress receiving device (1) includes a cylinder I (11) and a liner (15). The cylinder I (11) is connected to the outer end of the liner (15). A conical shell (12) and a cylinder II (13) are arranged sequentially on the outer side of the liner (15) in a direction away from the cylinder I (11). Ceramic fibers (16) are filled between the conical shell (12), the cylinder II (13) and the liner (15). The inner end of the cylinder II (13) is fixed to the equipment body of the quench tower. The stress absorption device (2) includes an outer sleeve (21) and a connecting pipe (22). The connecting pipe (22) is connected to the internal pipeline of the quench tower. The connecting pipe (22) is inserted into the outer sleeve (21). The outer side of the inner end of the liner (15) is fixed on the inner wall of the outer sleeve (21). There is a gap between the inner end of the liner (15) and the end of the connecting pipe (22).

2. The device for preventing high-temperature thermal stress damage at the gas phase feed inlet of the quench tower according to claim 1, characterized in that, An annular cover plate (14) is provided between the inner end of the cylindrical body II (13) and the equipment body of the quench tower. The inner end of the cylindrical body II (13) is welded to the outer side of the annular cover plate (14), and the edge of the annular cover plate (14) is welded to the equipment body of the quench tower. The ceramic fiber (16) fills the cavity formed by the conical shell (12), the cylindrical body II (13), the annular cover plate (14) and the liner (15).

3. The device for preventing high-temperature thermal stress damage at the gas phase feed inlet of the quench tower according to claim 2, characterized in that, A reinforcing ring (17) is installed on the outer side of the annular cover plate (14).

4. The device for preventing high-temperature thermal stress damage at the gas phase feed inlet of the quench tower according to claim 1, characterized in that, The cylindrical body I (11), the conical shell (12) and the cylindrical body II (13) are all composite plate structures. The composite plate structure includes a base layer, which is a non-alloy steel structure. The base layer is covered with a cladding layer, which is a high-alloy steel structure. The liner (15) is a high-alloy steel structure.

5. The device for preventing high-temperature thermal stress damage at the gas phase feed inlet of the quench tower according to claim 1, characterized in that, The inner end of the liner (15) is welded to the inner wall of the outer sleeve (21), and there is a gap between the inner end of the liner (15) and the end of the connector (22).

6. The device for preventing high-temperature thermal stress damage at the gas phase feed inlet of the quench tower according to any one of claims 1-5, characterized in that, The gap is 2-5mm.

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