CN220270170U - Uniform temperature conversion reactor of combined type water heat transfer tube bundle - Google Patents
Uniform temperature conversion reactor of combined type water heat transfer tube bundle Download PDFInfo
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- CN220270170U CN220270170U CN202321844658.1U CN202321844658U CN220270170U CN 220270170 U CN220270170 U CN 220270170U CN 202321844658 U CN202321844658 U CN 202321844658U CN 220270170 U CN220270170 U CN 220270170U
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 80
- 238000012546 transfer Methods 0.000 title claims abstract description 21
- 238000006243 chemical reaction Methods 0.000 title description 21
- 238000009826 distribution Methods 0.000 claims abstract description 39
- 238000001816 cooling Methods 0.000 claims abstract description 36
- 238000005452 bending Methods 0.000 claims abstract description 7
- 239000003054 catalyst Substances 0.000 claims description 31
- 230000007704 transition Effects 0.000 claims description 18
- 238000007789 sealing Methods 0.000 claims description 12
- 238000007599 discharging Methods 0.000 claims description 6
- 230000008602 contraction Effects 0.000 claims description 5
- 230000008646 thermal stress Effects 0.000 abstract description 7
- 238000004519 manufacturing process Methods 0.000 abstract description 6
- 238000003379 elimination reaction Methods 0.000 abstract description 2
- 239000007789 gas Substances 0.000 description 57
- 238000000034 method Methods 0.000 description 5
- 238000004939 coking Methods 0.000 description 4
- 238000013461 design Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000012545 processing Methods 0.000 description 3
- 229920006395 saturated elastomer Polymers 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000012824 chemical production Methods 0.000 description 1
- INILCLIQNYSABH-UHFFFAOYSA-N cobalt;sulfanylidenemolybdenum Chemical compound [Mo].[Co]=S INILCLIQNYSABH-UHFFFAOYSA-N 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000012495 reaction gas Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 230000035882 stress Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
- Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)
Abstract
The utility model provides a temperature-equalizing shift reactor of a combined water heat transfer tube bundle which is vertically grouped, comprising a pressure-bearing shell, a water-cooling heat transfer internal part, a cavity and a gas distribution chamber, wherein the water-cooling heat transfer internal part, the cavity and the gas distribution chamber are arranged in the pressure-bearing shell; the water-cooling heat-removing internal part comprises a water inlet pipe, a water diversion pipe box, a water-cooling heat exchange pipe bundle, a water collection pipe box and a water outlet pipe from bottom to top; the heat exchange tubes of the water-cooling heat exchange tube bundle are in a combination form of a plurality of straight tubes and bending coils with a certain inclination angle; the utility model adopts the structure form of the combined type water heat transfer heat exchange tube bundle, can realize the self-elimination of thermal stress of the internal part structure, avoid equipment leakage, ensure the production stability of the reactor and avoid the problem that the straight tube type reactor in the prior art is easy to pull apart.
Description
Technical Field
The utility model relates to a CO shift reactor, in particular to a temperature equalizing shift reactor of a combined type water heat transfer tube bundle.
Technical Field
The CO conversion process is used as a key technology and widely applied to the field of chemical production, wherein a CO conversion reactor is used as key production equipment, and has absolute guiding position on the technological flow and technical index of a conversion section. In the chemical technology development of recent decades in China, the CO conversion process is advanced from the original extensive traditional adiabatic process to the energy-saving and efficient isothermal process in recent years, the CO conversion reactor is also converted from the earliest adiabatic reactor into a water-cooling heat removal reactor with various structural forms, and the gas flow is also developed from the basic axial flow to the axial radial and full radial flow with lower pressure drop. The existing heat transfer and exchange reactor in China utilizes the circulating waterway to evaporate and transfer heat, so that the integral temperature control requirement of the catalyst bed is completely realized, the radial flow pattern design effectively reduces the resistance of the bed, and the heat transfer internal structure can realize self-unloading of the catalyst.
Although the existing heat transfer and change reactor technology level can basically meet the requirements of the change production, in actual production operation, some problems which are difficult to solve are still exposed. Firstly, the heat exchange internal part has the risk of leakage, the reaction heat generated by the conversion reaction can cause the heat exchange internal part to generate thermal stress, and if the internal part structure can not well eliminate the thermal stress, the local area of the heat exchange internal part can leak. Secondly, after the local leakage of the internal parts of the equipment occurs, the equipment is difficult to overhaul to a certain extent. Again, once the catalyst bed is over-temperature, there is some coking of the catalyst and catalyst caking that adheres to internals is difficult to handle when the equipment changes catalyst.
Disclosure of Invention
The utility model aims to solve the defects of the prior art, provides a uniform temperature conversion reactor of a combined water heat transfer tube bundle which is vertically grouped, realizes self-elimination of thermal stress of an internal structure, avoids equipment leakage, and provides a better structure on the aspects of equipment maintenance and catalyst coking treatment.
A temperature equalization conversion reactor of a combined type water heat transfer tube bundle comprises a pressure-bearing shell, and a water-cooling heat transfer internal part, a cavity and a gas distribution chamber which are arranged in the pressure-bearing shell. The pressure-bearing shell comprises an upper end enclosure, a cylinder body and a lower end enclosure, wherein the upper end enclosure is provided with a transformed gas inlet, a water outlet pipe and a manhole for overhauling personnel to enter and exit, and the lower end enclosure is provided with a transformed gas outlet, a water inlet and a catalyst self-discharging port;
the water-cooling heat-transferring internal part comprises a water inlet pipe, a water diversion pipe box, a water-cooling heat exchange pipe bundle, a water collection pipe box and a water outlet pipe from bottom to top. One end of the water collecting pipe box is connected with the water outlet pipe, the other end of the water collecting pipe box is connected with the coil pipe section of the heat exchange pipe through the upper contraction transition section, one end of the water distributing pipe box is connected with the straight pipe section of the heat exchange pipe through the lower contraction transition section, and the other end of the water distributing pipe box is connected with the water inlet pipe; when the production operation of the shift reactor has leakage problem, the maintainer can respectively enter the water diversion pipe box and the water collection pipe box through the water inlet pipe and the water outlet pipe, and the plugging maintenance of the heat exchange pipe is completed on the premise of not discharging the catalyst.
The heat exchange tubes of the water-cooling heat exchange tube bundle are in a combination form of a plurality of straight tubes and bending coils with a certain inclination angle, and each heat exchange tube comprises an upper shrinkage transition section, a coil section, a straight tube section and a lower shrinkage transition section from top to bottom. The staggered arrangement between the water diversion pipe box and the water collection pipe box is realized by bending the coil pipe section of the heat exchange pipe and then passing through the transitional contraction section. The heat exchange tube with the structural form has a thermal stress relief space with larger axiality and curvature, and ensures intrinsic safety of internal parts. Because the water diversion pipe boxes and the water collection pipe boxes are arranged in staggered mode, when the catalyst coking is treated, the central gas cylinder is extracted from the top of the reactor, and an maintainer can use the extracted assembly area as an operation space to treat the catalyst caking on the wall of the heat exchange pipe; the heat exchange tube bundles are arranged in a divergent mode at the tube plate shrinkage transition section, and after the catalyst is discharged, whether the internal parts are coked or not can be visually observed.
The water-cooling heat-removing internal parts are multiple groups, the main bed sections in the cavity are distributed in a concentric circular structure, so that the catalyst can be filled among the pipes, the pipe bundles among different layers are not crossed and blocked, and the filling condition of the catalyst can be clearly observed. The heat exchange tube is manufactured by processing a seamless stainless steel tube, and the material cost is reduced by adopting domestic high-quality tubular blank pipe fittings.
The gas distribution chamber comprises a fan-shaped sealing cover, a flat cover, a gas outer distribution cylinder, a central gas cylinder and a supporting ring, wherein the supporting ring is connected to the lower part of a cylinder section of the pressure-bearing shell, two ends of the gas outer distribution cylinder are respectively connected to the supporting ring and the flat cover, the gas outer distribution cylinder is coated outside a water-cooling heat-removing internal part, the fan-shaped sealing cover is arranged on the flat cover, the flat cover is connected to the gas outer distribution cylinder, a manhole is formed in the top of the flat cover, the on-site operation of an maintainer is facilitated, and the central gas cylinder is connected to the bottom of the lower seal head.
Preferably, the upper end enclosure is provided with a thermocouple port, and the temperature distribution of the bed layer is monitored in real time.
As one preferable mode, the water-cooling heat-transferring internal parts are 4 groups, the main bed sections in the cavity are distributed in a concentric circle structure, the water collecting pipe boxes and the water distributing pipe boxes are 4 groups respectively, and the tube plates of the upper group of pipe boxes and the lower group of pipe boxes are distributed in a staggered mode at 45 degrees.
Preferably, the bending inclination angle alpha of the coil pipe section is in the range of 30-70 degrees, and the height h of the coil pipe section is greater than 1/10 of the height of the straight pipe section and less than 1/6 of the height of the straight pipe section.
When the temperature-homogenizing shift reactor of the combined water heat transfer tube bundle carries out shift reaction, a cobalt-molybdenum sulfur-resistant shift catalyst or a presulfiding shift catalyst is filled in a cavity between the heat transfer tube bundles, the water-cooling heat transfer tube bundle distributes saturated boiler water through a water inlet pipe and a water distribution pipe box and then water flows from bottom to top, shift reaction gas enters from an inlet of the converter, passes through a catalyst layer to a central gas collecting cylinder along the radial direction after distributing flow through a gas outer distribution cylinder, and carries out CO shift reaction in the catalyst layer. In the reaction process, saturated boiler water in the water-cooling heat exchange tube bundle absorbs heat and phase changes to vaporize, shift reaction heat in the catalyst bed layer is removed, and gas is collected by a central gas collecting cylinder and then is discharged through a shifted gas outlet to carry out surplus reaction heat. The steam-water mixture which absorbs heat and is vaporized by the water-cooling heat exchange tube bundle rises to the water collecting tube box along the tube side and is discharged through the water outlet tube, and steam is produced by the steam generating system.
The reactor of the utility model has the following advantages:
1. the structural form of the combined type water heat transfer heat exchange tube bundle effectively eliminates thermal stress in axiality and curvature, ensures the production stability of the reactor, and avoids the problem that the straight tube type reactor in the prior art is easy to crack;
2. the heat exchange tubes used by the combined water-cooling heat transfer internal part are basically equal in length, material waste is avoided, unified processing is convenient, and the coil pipe part can be prefabricated and bent in advance.
3. The upper and lower tube boxes are distributed in a staggered mode, the upper space is smaller than that of the traditional tube boxes, the stress born by the transition section of the tube bundle is smaller, and the problem that leakage points are easy to occur at the position of the similar structure is solved.
4. According to the combined type water-cooling heat-transferring internal part structure, the thermal stress can be eliminated by the structural design, and an expansion joint structure is not required to be additionally arranged at the joint of the end socket water outlet pipe;
5. the internal part overhaul can be performed in the water diversion pipe box and the water collection pipe box, the large flange design is omitted by the shell, and the equipment processing period and the equipment cost are reduced;
6. the structure of the utility model adopts a radial reactor structure, adopts a gas distributor, radial outward distribution and an inward collection structure, ensures that gas is uniformly distributed along the height of a bed layer, ensures that the gas is more fully contacted with a catalyst, improves the service efficiency of the catalyst, reduces the pressure drop of the bed layer and reduces the energy consumption of the system.
7. The central gas cylinder of the reactor can be extracted from the top in a segmented way, and an maintainer can enter the equipment to confirm the filling condition of the catalyst and clean the coking of the catalyst.
Description of the drawings:
fig. 1 is a schematic structural view of the present utility model.
FIG. 2 is a schematic view of the azimuth distribution of the water distribution pipe and the water collection pipe box of the present utility model.
FIG. 3 is a schematic view of the structure of a flat cover and a sector-shaped sealing cover in the reactor of the present utility model.
Fig. 4 is a schematic view of a heat exchange tube assembly according to the present utility model.
Reference numerals illustrate:
1-change gas inlet 2-pressure-bearing shell 3-water outlet pipe 4-manhole
5-water collecting pipe tank 6-gas external distribution cylinder 7-1 straight pipe section 7-2 coil pipe section
7-3 upper shrink transition 7-4 lower shrink transition 8-cavity 9-support ring
10-center gas cylinder 11-diversion pipe box 12-water inlet pipe 13-converted gas outlet
14-catalyst self-discharging port 15-gas distributor 16-flat cover 17-sector sealing cover
18-center gas cylinder hole cover 19-upper tube bundle opening
Detailed Description
The following describes in detail the examples of the present utility model, which are implemented on the premise of the technical solution of the present utility model, and detailed embodiments and specific operation procedures are given, but the scope of protection of the present utility model is not limited to the following examples.
The uniform temperature shift reactor with staggered distribution of the upper and lower pipe boxes as shown in fig. 1 comprises a pressure-bearing shell 2, a water-cooling heat-removing internal part arranged in the pressure-bearing shell, a cavity 8 and a gas distribution chamber. The pressure-bearing shell 2 comprises an upper sealing head, a cylinder body and a lower sealing head, wherein the upper sealing head is provided with a conversion gas inlet 1, a water outlet pipe 3 and a manhole 4, and a gas distributor 15 is arranged in the conversion gas inlet 1. The lower seal head is provided with a converted gas outlet 13, a water inlet pipe 12 and a catalyst self-discharging port 14. The pressure-bearing shell 2 is internally provided with a water-cooling heat-removing internal part, a cavity 8 and a gas distribution chamber, and the lower end enclosure is provided with a transformed gas outlet 13, a water inlet pipe 12 and a catalyst self-discharging port 14;
the water-cooling heat-transferring internal part comprises a water inlet pipe 12, a water distribution pipe box 11, a water-cooling heat exchange pipe bundle, a water collecting pipe box 5 and a water outlet pipe 3 which are sequentially connected from bottom to top, wherein the heat exchange pipe of the water-cooling heat exchange pipe bundle is in a combination form of a plurality of straight pipes and bending coils, and comprises an upper shrinkage transition section 7-3, a coil section 7-2, a straight pipe section 7-1 and a lower shrinkage transition section 7-4 from top to bottom. The water-cooling heat-transferring internal parts of the embodiment are 4 groups, the main bed sections in the cavity are distributed in a concentric circular structure, and the gaps of the heat exchange pipes are filled with catalysts; as shown in fig. 2, the four groups of tube plates of the water collecting tube box and the four groups of tube plates of the water distributing tube box are arranged in an azimuth staggered manner by 45 degrees.
The gas distribution chamber comprises a fan-shaped sealing cover 17, a flat cover 16, a gas outer distribution cylinder 6, a central gas cylinder 10 and a support ring 9, wherein the support ring 9 is connected to the lower part of a cylinder section of the pressure-bearing shell 2, two ends of the gas outer distribution cylinder 6 are respectively connected to the support ring 9 and the flat cover 16, the gas outer distribution cylinder 6 is coated outside a water-cooling heat-removing inner part, as shown in fig. 3, the fan-shaped sealing cover 17 is arranged on the flat cover 16, a central pipe hole cover 18 and an upper pipe bundle opening 19 are further arranged on the flat cover 16, and the flat cover 16 is connected to the gas outer distribution cylinder 6.
The gas outer distribution cylinder 6 and the central gas cylinder 10 extend in the axial direction of the radial flow pressure-bearing housing 2 and the central gas cylinder 10 is located in the center of the gas distribution cylinder 6, the gas outer distribution cylinder 6 being connected to the support ring 9, the central gas cylinder 10 being in communication with the shifted gas outlet 13. The gaps among the heat exchange tubes of the 4 groups of water-cooling heat exchange tube bundles form a cavity 8 for filling a catalyst, and the cavity 8 is a large cavity with contracted upper and lower ends and a cylindrical middle part; the upper shrinkage transition section 7-3 and the lower shrinkage transition section 7-4 of the water-cooling heat exchange tube bundle are respectively welded on the corresponding water collecting tube tank and the tube plates of the water diversion tube tank.
After the conversion gas enters through the conversion gas inlet 1, the flow is uniformly distributed through the gas holes on the gas distributor 15 and the gas outer distribution cylinder 6 in sequence, and the conversion gas enters into the catalyst bed between the water-cooling heat exchange tube bundles to react; the converted gas after reaction enters the central gas cylinder from the air hole on the central gas cylinder 10 and finally flows out from the converted gas outlet 13 at the bottom of the shell; the heat generated by the conversion reaction is taken away by the vaporization and heat absorption of saturated boiler water in the water-cooling heat exchange tube bundle.
As shown in fig. 4, the heat exchange tube assembly of the present embodiment is realized by a lower contracted transition section 7-4, a straight tube section 7-1, a coil section 7-2 bent at a certain inclination angle, and an upper contracted transition section 7-3. Wherein the inclination angle alpha of the bent coil pipe section 7-2 ranges from 30 degrees to 70 degrees, and the height h of the coil pipe section is larger than the height of the 1/10 straight pipe section and smaller than the height of the 1/6 straight pipe section.
Claims (5)
1. The utility model provides a samming transform reactor of combination formula water heat transfer tube bank, includes the pressure-bearing casing to and set up water-cooling heat transfer internals, cavity and gas distribution room in the pressure-bearing casing, its characterized in that:
the pressure-bearing shell comprises an upper end enclosure, a cylinder body and a lower end enclosure, wherein the upper end enclosure is provided with a transformed gas inlet, a water outlet pipe and a manhole, and the lower end enclosure is provided with a transformed gas outlet, a water inlet and a catalyst self-discharging port;
the water-cooling heat-removing internal part comprises a water inlet pipe, a water diversion pipe box, a water-cooling heat exchange pipe bundle, a water collection pipe box and a water outlet pipe from bottom to top;
the heat exchange tubes of the water-cooling heat exchange tube bundle are in a combination form of a plurality of straight tubes and bending coils, and comprise an upper shrinkage transition section, a coil section, a straight tube section and a lower shrinkage transition section from top to bottom;
one end of the water collecting pipe box is connected with the water outlet pipe, the other end of the water collecting pipe box is connected with the coil pipe section of the heat exchange pipe through the upper contraction transition section, one end of the water distributing pipe box is connected with the straight pipe section of the heat exchange pipe through the lower contraction transition section, and the other end of the water distributing pipe box is connected with the water inlet pipe;
the water-cooling heat-removing internal parts are multiple groups, the main bed sections in the cavity are distributed in a concentric circular structure, and the gaps of the heat exchange pipes are filled with catalysts; the plane distribution direction of the water collecting pipe box and the plane distribution direction of the water diversion pipe box are staggered;
the gas distribution chamber comprises a fan-shaped sealing cover, a flat cover, a gas outer distribution cylinder, a central gas collecting cylinder and a supporting ring, wherein the supporting ring is connected to the lower part of a cylinder section of the pressure-bearing shell, two ends of the gas outer distribution cylinder are respectively connected to the supporting ring and the flat cover, the gas outer distribution cylinder is coated outside the water-cooling heat-removing internal part, the fan-shaped sealing cover is arranged on the flat cover, the flat cover is connected to the gas outer distribution cylinder, and the central gas collecting cylinder is connected to the bottom of the lower sealing head.
2. The homogeneous shift reactor of the combined type water-shift heat pipe bundle according to claim 1, wherein: the water-cooling heat-removing internal parts are 4 groups, the water collecting pipe boxes and the water distribution pipe boxes are 4 groups respectively, and the orientation distribution of the pipe plates is 45-degree dislocation distribution.
3. The homogeneous shift reactor of the combined type water-shift heat pipe bundle according to claim 1, wherein: the top of the flat cover is provided with a manhole.
4. The homogeneous shift reactor of the combined type water-shift heat pipe bundle according to claim 1, wherein: the upper end socket is provided with a thermocouple port.
5. The homogeneous shift reactor of the combined type water-shift heat pipe bundle according to claim 1, wherein: the bending inclination angle alpha of the coil pipe section ranges from 30 degrees to 70 degrees, and the height h of the coil pipe section is larger than the height of a 1/10 straight pipe section and smaller than the height of a 1/6 straight pipe section.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321844658.1U CN220270170U (en) | 2023-07-13 | 2023-07-13 | Uniform temperature conversion reactor of combined type water heat transfer tube bundle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321844658.1U CN220270170U (en) | 2023-07-13 | 2023-07-13 | Uniform temperature conversion reactor of combined type water heat transfer tube bundle |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220270170U true CN220270170U (en) | 2023-12-29 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202321844658.1U Active CN220270170U (en) | 2023-07-13 | 2023-07-13 | Uniform temperature conversion reactor of combined type water heat transfer tube bundle |
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| Country | Link |
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| CN (1) | CN220270170U (en) |
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- 2023-07-13 CN CN202321844658.1U patent/CN220270170U/en active Active
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