Anti-overtemperature and anti-corrosion cold oil tank structure in up-flow fluidized bed reactor
By designing a cold oil tank structure in an upstream boiling bed reactor, and mixing reaction passivation oil with raw oil and gas, the hot spots and coking problems caused by uneven temperature of the catalyst bed are solved, and the stable use of the catalyst and the long-term operation of the reaction system are achieved.
Patent Information
- Application Number
- CN202421625156.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-10
- Publication Date
- 2025-05-16
- Estimated Expiration
- 2034-07-10
AI Technical Summary
In the upstream boiling bed reactor, the uneven temperature of the catalyst bed leads to hot spots, the catalyst is locally coking, and the existing quench hydrogen injection method is prone to destroy the catalyst, resulting in powdering and crushing.
A cold oil tank structure is designed, using the high unit volume heat capacity of the reaction passivation oil, mixing it with the raw oil and gas through the nozzle, and then cooling it into the boiling bed, evenly reducing the initial reaction temperature of the bed, and controlling the average reaction temperature of the bed.
Effectively prevent catalyst powdering and coking, extend the service life of the catalyst, avoid the catalyst quenching and crushing caused by excessive temperature difference, and ensure the stable operation of the reaction system.
Smart Images
Figure CN222872131U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of fluidized bed reactors, in particular to a cold oil tank structure capable of preventing overheating and corrosion inside an upflow fluidized bed reactor. Background Art
[0002] In the chemical production process, the upflow fluidized bed reactor is widely used in catalytic reactions and adsorption processes. Its working principle is to evenly mix and distribute the oil and gas through the distribution plate, and then pass through the catalyst bed. The high-speed oil and gas move upward with the hydrogen evenly mixed, and the oil and gas are separated from the catalyst particles. The catalyst particles remain in the reactor, and the oil and gas enter the next stage. After this reaction system has been running for a period of time, the bed temperature is often uneven, the radial or lateral temperature difference reaches 100°C, and the catalyst bed hot spots appear, resulting in local coking of the catalyst, and finally the reaction system cannot continue to operate.
[0003] The existing reaction system cooling measures are: injecting quenching hydrogen in the middle of the catalyst bed or at the inlet and outlet of the reactor. This method is feasible in the fixed bed process, but in the boiling bed, when the catalyst and oil and gas are operating at a high temperature of 300-380°C, the sudden injection of quenching hydrogen at about 100°C (the heat capacity per unit volume is small, and the cooling requirement can only be met by a large temperature difference with the raw materials), causes the catalyst strength to be instantly destroyed, and powdering and breakage occur during operation. Summary of the invention
[0004] In order to overcome the shortcomings and deficiencies in the prior art, the utility model aims to provide a cold oil tank structure for preventing overheating and corrosion inside an upflow fluidized bed reactor.
[0005] The purpose of the utility model is achieved through the following technical solutions: a cold oil tank structure for preventing overheating and corrosion inside an upflow fluidized bed reactor, the cold oil tank structure is installed between a raw material distributor and a supporting grid in a reactor shell, a raw material distribution plate is fixed on the top of the raw material distributor, a plurality of first nozzles are fixed on the top of the raw material distribution plate, each of the first nozzles is connected to the raw material distributor, the cold oil tank structure includes a bottom ring, a trumpet-shaped annular support wall fixed to the top of the bottom ring, and a cold oil ring pipe fixed to the top of the annular support wall, a plurality of second nozzles are fixed on the top of the cold oil ring pipe, each of the second nozzles is connected to the cold oil ring pipe, and the cold oil ring pipe is connected to a feed pipe for conveying reaction passivation oil.
[0006] Furthermore, the bottom ring is fixed to the top of the raw material distribution plate by a first bolt.
[0007] Furthermore, the outer surface of the annular support wall has a plurality of reinforcing plates in an annular array.
[0008] Furthermore, a hydrogen inlet is provided on the side wall of the feed pipe.
[0009] Furthermore, the cooling oil ring pipe is composed of multiple sections of arc-shaped pipes connected in sequence.
[0010] Furthermore, the connection points of two adjacent arc-shaped tubes are fixedly connected by a flange.
[0011] Furthermore, the annular support wall is composed of a plurality of arc-shaped blocks connected in sequence.
[0012] Furthermore, the connection between two adjacent arc blocks is fixedly connected by a second bolt.
[0013] The beneficial effects of the utility model are as follows: the cold oil tank structure of the utility model adopts reaction passivation oil, which has a large heat capacity per unit volume and can meet the cooling requirement with a small temperature difference with the raw material. The reaction passivation oil can be directly heated to the required temperature and mixed with the high-temperature raw material to reduce the raw material temperature and dilute the raw material, thereby reducing the initial reaction temperature of the subsequent bed or reducing the temperature rise of the subsequent bed; the reaction passivation oil enters the cold oil ring tube through the feed pipe, is sprayed out through the second nozzle on the cold oil ring tube, is uniformly mixed with the raw oil (or oil-gas mixture) sprayed out by the first nozzle, and enters the boiling bed after cooling; the initial reaction temperature of the entire boiling bed can be uniformly reduced, thereby controlling the average reaction temperature of the bed, extending the service life of the catalyst, preventing catalyst pulverization, and inhibiting catalyst coking.
[0014] The cold oil tank structure of the utility model mainly provides a place for uniform mixing of raw materials and cold oil, avoiding uneven mixing, local hot spots and uneven catalyst distribution during the reaction with the catalyst. The cold oil tank structure of the utility model is applied to the reactor internals, which can effectively suppress the high-temperature hot spots of the bed layer, and will not cause the catalyst to be pulverized due to the sudden injection of low-temperature medium into the bed layer, resulting in catalyst loss, blockage and wear of subsequent equipment, pipelines and instruments in the system, and even serious consequences such as the inability of the device to continue to operate.
[0015] In actual use, the temperature of the cold oil tank structure of the utility model is much higher than that of other cooling media, and can be close to the temperature of the raw materials at most. The main purpose is to avoid the catalyst from being rapidly cooled and broken or pulverized due to excessive temperature difference. At this time, the reaction passivation property of the reaction passivation oil is used to mix with the raw oil gas to reduce the acid value of the original reaction material and dilute the concentration of reactants such as S and N, so as to finally achieve the purpose of reducing the reaction temperature rise. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a structural schematic diagram of the utility model.
[0017] Figure 2It is a front view of the cold oil tank structure of the utility model.
[0018] Figure 3 It is a top view of the cold oil tank structure of the utility model.
[0019] The figures are marked as: reactor shell 1, raw material distributor 2, support grid 3, raw material distribution plate 4, first nozzle 41, bottom ring 5, first bolt 51, annular support wall 6, reinforcement plate 61, arc block 62, second bolt 63, cooling oil ring pipe 7, second nozzle 71, feed pipe 72, hydrogen inlet 73, arc pipe 74, flange 75. DETAILED DESCRIPTION
[0020] In order to facilitate the understanding of those skilled in the art, the following embodiments and attached Figure 1-3 To further illustrate the present invention, the contents mentioned in the implementation modes are not intended to limit the present invention.
[0021] See Figure 1-3 A cold oil tank structure for preventing overheating and corrosion inside an upflow fluidized bed reactor, wherein the cold oil tank structure is installed between a raw material distributor 2 and a supporting grid 3 in a reactor shell 1, a raw material distribution plate 4 is fixed on the top of the raw material distributor 2, a plurality of first nozzles 41 are fixed on the top of the raw material distribution plate 4, each of the first nozzles 41 is connected to the raw material distributor 2, the cold oil tank structure comprises a bottom ring 5, a trumpet-shaped annular support wall 6 fixed to the top of the bottom ring 5, and a cold oil ring pipe 7 fixed to the top of the annular support wall 6, a plurality of second nozzles 71 are fixed on the top of the cold oil ring pipe 7, each of the second nozzles 71 is connected to the cold oil ring pipe 7, and the cold oil ring pipe 7 is connected to a feed pipe 72 for conveying reaction passivation oil.
[0022] The cold oil tank structure of the utility model adopts reaction passivation oil, which has a large heat capacity per unit volume and can meet the cooling requirement with a small temperature difference with the raw material. The reaction passivation oil can be directly heated to the required temperature and mixed with the high-temperature raw material to reduce the raw material temperature and dilute the raw material, thereby reducing the initial reaction temperature of the subsequent bed or reducing the temperature rise of the subsequent bed. The reaction passivation oil enters the cold oil ring pipe 7 through the feed pipe 72, is sprayed out through the second nozzle 71 on the cold oil ring pipe 7, is uniformly mixed with the raw oil (or oil-gas mixture) sprayed out by the first nozzle 41, and enters the boiling bed after cooling. The initial reaction temperature of the entire boiling bed can be uniformly reduced, which plays a role in controlling the average reaction temperature of the bed, extending the service life of the catalyst, preventing the catalyst from pulverizing, and inhibiting the coking of the catalyst.
[0023] In this embodiment, the bottom ring 5 is fixed to the top of the raw material distribution plate 4 by a first bolt 51. The above structure is convenient for the installation of the cold oil tank. The detachable cold oil tank is convenient for regular inspection, cleaning and maintenance, which effectively prolongs the service life of this component;
[0024] In this embodiment, the outer surface of the annular support wall 6 is provided with a plurality of reinforcing plates 61 in an annular array. The above-mentioned structure can improve the strength of the annular support wall 6.
[0025] In this embodiment, a hydrogen inlet 73 is provided on the side wall of the feed pipe 72. When the cooling oil is not normally used, hydrogen can be introduced to replace and flush the pipeline to avoid the blockage of the cooling oil pipeline by impurities and liquid.
[0026] In this embodiment, the cooling oil ring pipe 7 is composed of multiple arc-shaped pipes 74 connected in sequence. The above structure is convenient for disassembly and assembly of the cooling oil ring pipe 7. Specifically, the connection between two adjacent arc-shaped pipes 74 is fixedly connected by a flange 75.
[0027] In this embodiment, the annular support wall 6 is composed of a plurality of arc blocks 62 connected in sequence. The above structure is convenient for disassembly and assembly of the annular support wall 6. Specifically, the connection between two adjacent arc blocks 62 is fixedly connected by a second bolt 63.
[0028] The above embodiments are preferred implementation schemes of the present invention. In addition, the present invention can also be implemented in other ways. Any obvious replacement without departing from the concept of the present invention is within the protection scope of the present invention.
Claims
1. A cold oil tank structure for preventing overheating and corrosion inside an upflow fluidized bed reactor, the cold oil tank structure being installed between a raw material distributor and a support grid in a reactor shell, characterized in that: A raw material distribution plate is fixed on the top of the raw material distributor, and a plurality of first nozzles are fixed on the top of the raw material distribution plate, each of which is connected to the raw material distributor. The cold oil tank structure includes a bottom ring, a trumpet-shaped annular support wall fixed to the top of the bottom ring, and a cold oil ring pipe fixed to the top of the annular support wall. A plurality of second nozzles are fixed on the top of the cold oil ring pipe, and each of which is connected to the cold oil ring pipe. The cold oil ring pipe is connected to a feed pipe for conveying reaction passivation oil.
2. The cold oil tank structure for preventing overheating and corrosion inside an upflow fluidized bed reactor according to claim 1, characterized in that: The bottom ring is fixed to the top of the raw material distribution plate by a first bolt.
3. The cold oil tank structure for preventing overheating and corrosion inside an upflow fluidized bed reactor according to claim 1, characterized in that: The outer surface of the annular support wall is provided with a plurality of reinforcing plates in an annular array.
4. The cold oil tank structure for preventing overheating and corrosion inside an upflow fluidized bed reactor according to claim 1, characterized in that: A hydrogen inlet is arranged on the side wall of the feed pipe.
5. The cold oil tank structure for preventing overheating and corrosion inside an upflow fluidized bed reactor according to claim 1, characterized in that: The cooling oil ring pipe is composed of a plurality of arc-shaped pipe sections connected in sequence.
6. The cold oil tank structure for preventing overheating and corrosion inside an upflow fluidized bed reactor according to claim 5, characterized in that: The connection points of two adjacent arc-shaped tubes are fixedly connected by flanges.
7. The cold oil tank structure for preventing overheating and corrosion inside an upflow fluidized bed reactor according to claim 1, characterized in that: The annular supporting wall is composed of a plurality of arc-shaped blocks connected in sequence.
8. The cold oil tank structure for preventing overheating and corrosion inside an upflow fluidized bed reactor according to claim 7, characterized in that: The connection between two adjacent arc-shaped blocks is fixedly connected by a second bolt.