Fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride
By designing a fluidized bed oxidation reactor for preparing chlorine gas including a shell, a gas distributor, a fluidized bed, a heat exchange device and a gas-solid separation device, the problems of poor heat transfer performance and low catalyst activity utilization of existing fixed bed and slurry bed reactors are solved, and the effect of high reaction efficiency and stable operation is achieved.
Patent Information
- Application Number
- CN202421493219.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-27
- Publication Date
- 2025-05-09
- Estimated Expiration
- 2034-06-27
AI Technical Summary
The existing fixed bed and slurry bed reactors for preparing chlorine gas for hydrogen chloride have problems such as poor heat transfer performance, low catalyst activity utilization, inconvenient catalyst regeneration and replacement, and equipment corrosion, which is difficult to meet the needs of industrial applications.
A fluidized bed oxidation reactor for preparing chlorine gas by hydrogen chloride is designed, including a shell, a gas distributor, a fluidized bed, a heat exchange device and a gas-solid separation device. The reactor evenly distributes the gas through a gas distributor, adds a catalyst to the fluidized bed, heat exchange device performs heat exchange, and gas-solid separation device separates the catalyst particles to improve the reaction efficiency and catalyst utilization rate.
It has achieved the advantages of high reaction efficiency, stable operation, strong anti-interference ability, excellent catalyst performance, and equipment structure and maintenance costs, and is suitable for industrial applications.
Smart Images
Figure CN222842065U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of oxidation reactors, in particular to a fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride. Background Art
[0002] With the rapid development of chlorine chemicals in my country, especially the rapid expansion of organochlorine products in the past decade, a large amount of by-product hydrogen chloride has been produced.
[0003] Directly converting hydrogen chloride (HCl) into chlorine through catalytic oxidation can achieve closed-loop circulation of chlorine and zero emission in the production process, which can not only solve the problems of excessive hydrogen chloride and high power consumption in chlorine production, but also improve the chlor-alkali balance and optimize and upgrade the chlor-alkali industry. This technology is conducive to converting by-product hydrogen chloride in various industries into chlorine, and has great application potential. In the next few years, catalytic oxidation technology for producing chlorine will be one of the hot research technologies in the chlor-alkali industry and a focus of great concern in the industry.
[0004] The main reactors for producing chlorine from hydrogen chloride include fixed bed reactors, fluidized bed reactors and slurry bed reactors. Among them, fixed bed reactors and slurry bed reactors for producing chlorine by catalytic oxidation have been industrialized, while fluidized bed reactors have not been industrialized. However, the shortcomings of fixed bed reactors and slurry bed reactors cannot meet the use requirements, as follows:
[0005] The fixed bed process of producing chlorine from hydrogen chloride is as follows: the catalyst is fixed in the reactor, and the catalyst contacts the hydrogen chloride gas to generate chlorine through oxidation reaction. It has the following disadvantages:
[0006] 1. Poor heat transfer performance: In a fixed bed reactor, the solid catalyst is stationary, and the catalyst carrier is often a poor conductor of heat. This leads to poor heat transfer performance of the fixed bed and difficulty in temperature control. Especially in exothermic reactions, hot spots are prone to occur in fixed bed reactors, that is, the temperature of a certain area in the reactor rises, which may cause the reaction to run away.
[0007] 2. Low utilization rate of the active inner surface of the catalyst: Due to the fixed nature of the catalyst particles in the fixed bed reactor, the active inner surface of the catalyst cannot be fully utilized, especially for fine-particle catalysts, whose active surface cannot fully contact with the reactants, thereby reducing the reaction efficiency.
[0008] 3. Inconvenient catalyst regeneration and replacement: The catalyst in the fixed bed reactor will gradually lose its activity during long-term use and needs to be regenerated or replaced. However, since the catalyst particles are fixed in the bed, the regeneration and replacement process is relatively complicated and difficult to operate.
[0009] The slurry bed process of producing chlorine from hydrogen chloride is as follows: the catalyst is mixed with the reaction liquid to form a slurry. In the slurry bed reactor, the slurry catalyst contacts the hydrogen chloride gas and an oxidation reaction occurs to generate chlorine. It has the following disadvantages:
[0010] 1. Catalyst activity decline: During the reaction process, the catalyst may decline in activity due to adsorption of reactants, blockage or deactivation of the catalyst itself, which will affect the efficiency of the reactor and the yield of chlorine.
[0011] 2. Equipment corrosion: Since chlorine is highly corrosive, the hydrogen chloride chlorine slurry bed reactor and its related equipment are susceptible to corrosion, which may shorten the life of the equipment and increase the cost of maintenance and replacement.
[0012] 3. Reactor stability: Under high temperature and high pressure conditions, the catalyst particles inside the reactor are prone to agglomeration and precipitation, which affects the stability of the reactor and the mass transfer effect.
[0013] Therefore, there is an urgent need for a fluidized bed reactor that can be used industrially. Summary of the invention
[0014] In view of the above situation, in order to overcome the defects of the prior art, the utility model provides a fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride to solve the problems involved in the background technology.
[0015] To achieve the above object, the utility model provides the following technical solution: a fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride, comprising a shell, a gas distributor and a fluidized bed arranged inside the shell, a heat exchange device arranged above the gas distributor, and a gas-solid separation device arranged above the heat exchange device;
[0016] The heat exchange device comprises a cooling tube bundle, a cooling tube bundle outlet ring tube and a cooling tube bundle inlet ring tube connected to both ends of the cooling tube bundle;
[0017] The gas-solid separation device is composed of multiple cyclone separators, including a cylinder, a cone cylinder arranged at the lower end of the cylinder, a particle discharge pipe connected to the lower end of the cone cylinder, a drip valve is provided at the end of the particle discharge pipe, a tangential injection pipe is provided on one side of the cylinder, and a center pipe is provided above the cylinder.
[0018] Furthermore, the tangential injection pipe is provided with a tangential inlet or a spiral inlet;
[0019] A cover plate is arranged above the cylinder.
[0020] Furthermore, the end of the particle discharge pipe is immersed in the fluidized bed.
[0021] Furthermore, a raw material air inlet pipe is provided on one side of the shell, and the raw material air inlet pipe is connected to a gas distributor, and the gas distributor is composed of a plurality of short tubes.
[0022] Furthermore, the fluidized bed is arranged above the gas distributor, and a catalyst is arranged in the fluidized bed.
[0023] Furthermore, the shell includes a cylinder, an upper head arranged at the upper end of the cylinder, and a lower head arranged below the bottom of the cylinder, and a skirt seat is also provided on the lower side of the shell.
[0024] Furthermore, a hanger and a material leg fixing frame are provided inside the shell, and the hanger and the material leg fixing frame are used to fix the upper and lower sides of the gas-solid separation device respectively.
[0025] Furthermore, a cooling tube bundle support frame and a cooling tube bundle fixing frame are provided inside the shell, the upper end of the heat exchange device is fixed to the cooling tube bundle support frame by U-bolts, and the middle and lower side of the heat exchange device are fixed to the cooling tube bundle fixing frame.
[0026] Furthermore, the cooling tube bundle is composed of multiple groups of parallel tube bundles, each group of parallel tube bundles is composed of multiple tubes in an M-shaped tube tray, and each tube in a tube column is connected by an elbow.
[0027] Compared with the prior art, the beneficial effects of the utility model are:
[0028] The utility model has good reaction effect, high reaction rate, conversion rate and selectivity; strong operational stability and anti-interference ability; excellent performances such as catalyst activity, selectivity, stability and regeneration ability; and obvious advantages in structural design, service life, maintenance cost and other aspects of the shell, gas distributor, heat exchange device and gas-solid separation device. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Figure 1 This is a schematic diagram of the internal structure of Embodiment 1 of the present utility model;
[0030] Figure 2 This is a schematic diagram of the main structure of the gas-solid separation device of Example 1 of the utility model;
[0031] Figure 3 This is a top view of a three-dimensional structure diagram of a gas-solid separation device according to Embodiment 1 of the present utility model;
[0032] In the figure:
[0033] Shell 1, gas distributor 2, fluidized bed 3, heat exchange device 4, gas-solid separation device 5, skirt 6, hanger 7, feed leg fixing frame 8, cooling tube bundle support frame 9, cooling tube bundle fixing frame 10;
[0034] Cylinder body 11, upper head 12, lower head 13, lug 14, raw material inlet pipe 15;
[0035] Short tube 21;
[0036] Cooling tube bundle 41, cooling tube bundle outlet ring pipe 42, cooling tube bundle inlet ring pipe 43, elbow 44, U-bolt 45;
[0037] Cylinder 51, cone 52, particle discharge pipe 53, drip valve 54, tangential injection pipe 55, center pipe 56, cover plate 57. DETAILED DESCRIPTION
[0038] The technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments; based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.
[0039] Embodiment 1:
[0040] Depend on Figure 1-3 As shown, a fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride comprises a shell 1, a gas distributor 2 and a fluidized bed 3 arranged inside the shell 1, a heat exchange device 4 arranged above the gas distributor 2, and a gas-solid separation device 5 arranged above the heat exchange device 4;
[0041] The shell 1 comprises a cylinder 11, an upper end cap 12 disposed at the upper end of the cylinder 11, and a lower end cap 13 disposed below the cylinder 11. A skirt 6 is further disposed on the lower side of the shell 1. The gas distributor 2 is disposed above the inner side of the lower end cap 13.
[0042] The shell 1 is provided with a hanger 7 and a material leg fixing frame 8, and the hanger 7 and the material leg fixing frame 8 are used to fix the upper and lower sides of the gas-solid separation device 5 respectively. The shell 1 is provided with a cooling tube bundle support frame 9 and a cooling tube bundle fixing frame 10. The upper end of the heat exchange device 4 is fixed to the cooling tube bundle support frame 9 by a U-bolt 45, and the middle and lower side of the heat exchange device 4 are fixed to the cooling tube bundle fixing frame 10. A plurality of support ears 14 are provided on the inner side of the cylinder 11, and the cooling tube bundle fixing frames 10 at multiple locations are connected to the support ears 14 by bolts.
[0043] The heat exchange device 4 includes a cooling tube bundle 41, a cooling tube bundle outlet ring pipe 42 and a cooling tube bundle inlet ring pipe 43 connected to both ends of the cooling tube bundle 41; the cooling tube bundle 41 is composed of multiple groups of parallel tube bundles, each group of parallel tube bundles is composed of multiple tubes in an M-shaped tube coil, and each tube is connected by an elbow 44. The reaction of chlorine gas produced by catalytic oxidation of hydrogen chloride is an exothermic reaction, and the heat exchange device 4 is set to exchange heat. The heat exchange device 4 is provided with 9 to 73 groups of parallel tube bundles, and each group of tube bundles is composed of 10 to 12 tubes.
[0044] The reaction process of the present application is an exothermic process. The heat exchange device 4 arranged in the reactor adopts a tube coil formed by a tube bundle, which has good heat transfer effect, uniform temperature distribution, and small diffusion resistance in the catalyst.
[0045] The gas-solid separation device 5 is composed of 2 to 5 cyclone separators connected in sequence, each cyclone separator is cascaded 2 to 3 stages, and the use of double-stage or multi-stage cyclone separators can solve the problem of incomplete separation of light and heavy substances in ordinary cyclone separators. When the gas passes through the catalyst at a speed of 0.2 to 0.4 m / s, the catalyst exhibits a stable turbulent flow. When the gas flow rate is lower than 0.2 m / s, a channel flow or turbulent flow will be formed in the catalyst. When the flow rate is high, it will cause the catalyst to be carried away. The cyclone separator can circulate the catalyst particles discharged from the fluidized bed, especially the fraction with a range of about 15 to 45 μm, to the fluidized bed. The cyclone separator includes a cylinder 51, a cone 52 arranged at the lower end of the cylinder 51, a particle discharge pipe 53 connected to the lower end of the cone 52, a drip valve 54 is arranged at the end of the particle discharge pipe 53, a tangential injection pipe 55 is arranged on one side of the cylinder 51, a center pipe 56 is arranged above the cylinder 51, and a cover plate 57 is arranged above the cylinder 51. The tangential injection pipe 55 is provided with a tangential inlet or a spiral inlet for the inlet of the product gas mixture. Due to the tangential or spiral inlet, the product gas mixture to be separated is given a spiral downward motion; the catalyst enters the particle discharge pipe through a conical cone, and the end of the particle discharge pipe 53 is immersed in the fluidized bed 3, which can prevent the gas mixture from bypassing through the particle discharge pipe 53, or ensure that the gas mixture passes through the cyclone separator completely or substantially completely through the tangential inlet; the central pipe 56 is used to discharge the product gas mixture from which the entrained catalyst particles have been removed, and 90-99% of the entrained catalyst particles are deposited to the drip valve 54 at the lower end.
[0046] The cyclone separator of the present application removes the entrained catalyst particles, prevents the loss of catalyst, and separates substances with different specific gravities from the gas. The cyclone separator has a simple structure and is easy to maintain.
[0047] A raw material inlet pipe 15 is provided on one side of the shell 1, and the raw material inlet pipe 15 is connected to a gas distributor 2, and the gas distributor 2 is composed of a plurality of short tubes 21. The gas distributor 2 is made of special materials to effectively avoid corrosion and extend the service life of the equipment. The raw material gas enters the oxidation reactor through the raw material inlet pipe 15 and is redistributed through the gas distributor 2. The gas distributor 2 evenly distributes the gas pressure, flow rate, and turbulent kinetic energy, effectively improving the fluidization effect, reaction performance, and catalyst life of the catalyst. The fluidized bed 3 is arranged above the gas distributor 2, and a catalyst is arranged in the fluidized bed 3.
[0048] The molar ratio of oxygen to hydrogen chloride gas in the oxidation reactor of the present application is 1:1-4, the reaction pressure is 0.1-0.5 MPa, the reaction temperature is 300-450°C, and the reaction conversion rate is ≥95%, which effectively improves the conversion rate of hydrogen chloride. The equipment is simple, the operation is stable, and the control is easy.
[0049] Hydrogen chloride gas and oxygen enter the reactor at a molar ratio of 4 to 1 for reaction, using a copper-based catalyst. The experimental results under different conditions are shown in Table 1:
[0050] Table 1
[0051]
[0052] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride, comprising a shell, a gas distributor and a fluidized bed arranged inside the shell, characterized in that: It also includes a heat exchange device arranged above the gas distributor, and a gas-solid separation device arranged above the heat exchange device; The heat exchange device comprises a cooling tube bundle, a cooling tube bundle outlet ring tube and a cooling tube bundle inlet ring tube connected to both ends of the cooling tube bundle; The gas-solid separation device is composed of multiple cyclone separators, including a cylinder, a cone cylinder arranged at the lower end of the cylinder, a particle discharge pipe connected to the lower end of the cone cylinder, a drip valve is provided at the end of the particle discharge pipe, a tangential injection pipe is provided on one side of the cylinder, and a center pipe is provided above the cylinder.
2. The fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride according to claim 1, characterized in that: The tangential injection pipe is provided with a tangential inlet or a spiral inlet; A cover plate is arranged above the cylinder.
3. The fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride according to claim 1, characterized in that: The end of the particle discharge pipe is immersed in the fluidized bed.
4. The fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride according to claim 1, characterized in that: A raw material air inlet pipe is provided on one side of the shell, and the raw material air inlet pipe is connected to a gas distributor, and the gas distributor is composed of a plurality of short pipes.
5. The fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride according to claim 1, characterized in that: The fluidized bed is arranged above the gas distributor, and a catalyst is arranged in the fluidized bed.
6. The fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride according to claim 1, characterized in that: The shell comprises a cylinder, an upper head arranged at the upper end of the cylinder, and a lower head arranged below the cylinder. A skirt seat is also arranged on the lower side of the shell.
7. The fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride according to claim 1, characterized in that: A hanger and a material leg fixing frame are arranged inside the shell, and the hanger and the material leg fixing frame are used to fix the upper and lower sides of the gas-solid separation device respectively.
8. The fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride according to claim 1, characterized in that: A cooling tube bundle support frame and a cooling tube bundle fixing frame are arranged inside the shell. The upper end of the heat exchange device is fixed to the cooling tube bundle support frame by U-shaped bolts, and the middle and lower side of the heat exchange device are fixed to the cooling tube bundle fixing frame.
9. The fluidized bed oxidation reactor for preparing chlorine from hydrogen chloride according to claim 1, characterized in that: The cooling tube bundle is composed of multiple groups of parallel tube bundles, each group of parallel tube bundles is composed of multiple tubes in an M-shaped tube tray, and each tube in a tube column is connected by an elbow.