Catalyst regeneration treatment system for catalytic cracking reaction, regeneration treatment method and application

Abstract

The application discloses a catalyst regeneration treatment system for catalytic cracking reaction, a regeneration treatment method and application. The catalyst regeneration treatment system comprises a regeneration gas feeding unit, a raw material feeding unit, a catalytic cracking reaction unit, a reaction product post-treatment unit and a regeneration tail gas treatment unit; the raw material feeding unit is a feeding unit for raw materials for the catalytic cracking reaction; the reaction product post-treatment unit is a post-treatment unit for reaction products of the catalytic cracking reaction; wherein, the feeding ports of the catalytic cracking reaction unit are switchably connected with the regeneration gas feeding unit and the raw material feeding unit respectively; the discharging ports of the catalytic cracking reaction unit are switchably connected with the reaction product post-treatment unit and the regeneration tail gas treatment unit respectively; and the reaction product post-treatment unit is provided with a displacement gas content detector. The catalyst regeneration treatment system and method have the advantages of reducing material waste and reducing the tail gas treatment amount in the olefin catalytic cracking regeneration process.

Description

Technical Field

[0001] This invention relates to the technical field of catalyst regeneration tail gas treatment in catalytic cracking reactions, and more specifically, to a catalyst regeneration treatment system, regeneration treatment method, and application for catalytic cracking reactions. Background Technology

[0002] Volatile organic compounds (VOCs) refer to organic compounds that participate in atmospheric photochemical reactions, generally calculated as non-methane hydrocarbons. VOCs emitted by chemical enterprises are a key target for environmental protection departments. By 2017, my country's petrochemical industry had basically completed comprehensive VOCs control work and established a VOCs monitoring system. According to the national standard GB16297 "Integrated Emission Standard for Air Pollutants," VOCs from organized exhaust stacks must not exceed 120 mg / m³. 3 Therefore, before the exhaust gas meets emission standards, it must be treated through recycling or combustion.

[0003] Olefin catalytic cracking reactors generally adopt a fixed-bed reactor type. Since the catalyst in an olefin catalytic cracking reactor cannot be continuously regenerated like the catalyst in a fluidized-bed reactor, at least two reactors are usually set up, one in operation and one on standby. After running for a period of time, a reverse-switching method is used to switch the reactors and regenerate the catalyst inside the reactor.

[0004] In-process catalyst regeneration typically employs air coking. Patent CN110124752A discloses a process for coking regeneration in olefin catalytic cracking. This method adjusts the air content in the regeneration gas based on the temperature of the top catalyst bed in the fixed bed, indirectly controlling the gentleness of the coking regeneration process and preventing catalyst bed overheating that could cause catalyst sintering damage.

[0005] Patent CN102407170A discloses a device and process for simultaneous coking of multiple catalyst beds in a fixed bed. By introducing regeneration gas between the beds and monitoring the oxygen content in the regeneration gas via online instruments, simultaneous coking of multiple catalyst beds is achieved, shortening the total coking time, saving energy consumption, and improving the production capacity of the unit. The above-disclosed patent technologies all focus on the control of regeneration coking in olefin catalytic cracking, but do not mention the destination and treatment method of the regeneration tail gas.

[0006] Patent CN111822059A discloses a device and method for hydrogenation catalyst regeneration and waste gas treatment. The device includes a first-stage waste gas treatment unit and a second-stage waste gas treatment unit. In the first stage, the waste gas from the regeneration system is purged with nitrogen and then treated in a flare system. In the second stage, the regeneration system is preheated with steam, followed by air combustion, with the combustion exhaust gas sent to an incinerator. This device and method prevent oxygen-containing waste gas from entering the flare system, enhancing system safety. However, the waste gas discharged into the flare system in the first stage is high-concentration VOCs, and the flare exhaust gas volume is large, resulting in significant carbon dioxide emissions after combustion. This method does not propose a process-based approach to reduce the exhaust gas volume.

[0007] Existing technologies have optimized the fixed-bed catalyst regeneration process in terms of coke control and regeneration tail gas disposal. However, directly sending the waste gas from the nitrogen purging regeneration system to the flare system for treatment will result in a large tail gas treatment volume for the flare. This is especially true for large-scale processing systems with large reaction systems and auxiliary piping systems. A large amount of process materials are discharged into tail gas treatment devices such as flares or incinerators during the replacement process, which not only increases the load on the tail gas treatment devices, but also leads to material waste and increased carbon dioxide emissions.

[0008] In summary, existing technologies all suffer from problems such as material waste and large tail gas volumes during catalyst regeneration in olefin catalytic cracking. This invention specifically addresses these problems. Summary of the Invention

[0009] To address the problems in existing technologies, this invention proposes a catalyst regeneration system, method, and application for catalytic cracking reactions. This invention can effectively reduce the mass of VOCs entering the regeneration tail gas treatment unit, allowing only a portion of potentially emitted VOCs to enter the unit. This effectively solves the problems of material waste and large tail gas volumes in the olefin catalytic cracking regeneration process of existing technologies.

[0010] One objective of this invention is to provide a catalyst regeneration system for a catalytic cracking reaction, comprising a regeneration gas feed unit, a raw material feed unit, a catalytic cracking reaction unit, a reaction product post-processing unit, and a regeneration tail gas treatment unit; wherein the regeneration gas comprises displacement gas and coke burner gas; the raw material feed unit is the feed unit for the raw materials used in the catalytic cracking reaction; and the reaction product post-processing unit is the post-processing unit for the reaction products of the catalytic cracking reaction.

[0011] The feed inlet of the catalytic cracking reaction unit is switched between the regeneration gas feed unit and the raw material feed unit.

[0012] The outlet of the catalytic cracking reaction unit is switched between the reaction product post-processing unit and the regeneration tail gas treatment unit.

[0013] The reaction product post-processing unit includes a compression unit, and a displacement gas content detector is installed on the inlet pipe of the compression unit.

[0014] In the catalyst regeneration system of the present invention, preferably,

[0015] The switching connection includes switching the connection by setting a material control switch on the corresponding connection pipeline; preferably, the material control switch includes a shut-off valve, a regulating valve and a blind plate;

[0016] More preferably,

[0017] The outlet of the raw material feeding unit is connected to the inlet pipeline of the catalytic cracking reaction unit, and a material control switch A is provided on the connecting pipeline between the two.

[0018] The outlet of the regenerated gas feed unit is connected to the inlet pipeline of the catalytic cracking reaction unit, and a material control switch B is installed on the connecting pipeline between the two.

[0019] The outlet of the catalytic cracking reaction unit is connected to the inlet of the reaction product post-processing unit, and a material control switch C is provided on the connecting pipeline between the two.

[0020] The outlet of the catalytic cracking reaction unit is connected to the inlet of the regeneration tail gas treatment unit, and a material control switch D is provided on the connecting pipeline between the two.

[0021] In the catalyst regeneration system of the present invention, preferably,

[0022] In addition to the material control switch B, the outlet pipeline of the regenerated gas feeding unit is also equipped with a regenerated gas flow regulating valve; the displacement gas content detector is electrically connected to the regenerated gas flow regulating valve.

[0023] Preferably, the displacement gas content detector is an online gas composition analyzer.

[0024] In the catalyst regeneration system of the present invention, preferably,

[0025] The displacement gas is selected from nitrogen; the displacement gas content detector is a nitrogen content detector.

[0026] The burnt gas is a mixture of air and nitrogen.

[0027] Preferably, the oxygen content in the coking gas is 0.5% to 5%.

[0028] In the catalyst regeneration system of the present invention, preferably,

[0029] The reaction product post-processing unit also includes a reaction product cooler and a separation unit;

[0030] A compression unit is connected between the reaction product cooler and the separation unit; the inlet of the reaction product cooler is connected to the outlet of the catalytic cracking reaction unit via a pipeline.

[0031] Preferably, the separation unit is a distillation column.

[0032] In the catalyst regeneration system of the present invention, preferably,

[0033] The catalytic cracking reaction unit includes a catalytic cracking reactor filled with a catalyst, and the number of the catalytic cracking reactors is one or more; the catalytic cracking reactors are connected in parallel and arranged in a switchable manner; preferably, the number of the catalytic cracking reactors is at least two.

[0034] In the catalyst regeneration system of the present invention, preferably,

[0035] The outlet of the raw material feeding unit is connected to the inlet of any catalytic cracking reactor, and a material control switch A is provided on the connecting pipeline between the raw material feeding unit and any catalytic cracking reactor.

[0036] The outlet of the regenerated gas feed unit is connected to the inlet of any catalytic cracking reactor, and a material control switch B is provided on the connecting pipeline between the regenerated gas feed unit and any catalytic cracking reactor.

[0037] The outlet of any catalytic cracking reactor is connected to the inlet of the reaction product post-processing unit, and a material control switch C is provided on the connecting pipeline between any catalytic cracking reactor and the reaction product post-processing unit.

[0038] The outlet of any catalytic cracking reactor is connected to the inlet of the regeneration tail gas treatment unit, and a material control switch D is provided on the connecting pipeline between any catalytic cracking reactor and the regeneration tail gas treatment unit.

[0039] In the catalyst regeneration system of the present invention, preferably,

[0040] The catalytic cracking reactor is a fixed-bed reactor; and / or

[0041] The regenerated exhaust gas treatment unit includes a flare and / or an incinerator.

[0042] The second objective of this invention is to provide a method for regenerating a catalyst in a catalytic cracking reaction, comprising the following steps:

[0043] (1) When the catalyst used in the catalytic cracking reaction is deactivated, the feed of the reaction raw materials in the catalytic cracking reaction system is stopped, and the replacement gas is fed into the catalytic cracking reaction system as regeneration gas. The gas in the catalytic cracking reaction system is discharged to the reaction product post-processing system. The content of replacement gas in the gas discharged from the catalytic cracking reaction system is detected before the feed inlet of the compression unit in the reaction product post-processing system.

[0044] (2) When the detected value of the replacement gas content exceeds the replacement gas content control value, the gas discharge from the catalytic cracking reaction system to the reaction product post-processing system is stopped, and the gas in the catalytic cracking reaction system is switched to the regeneration tail gas treatment system for tail gas treatment; the replacement of hydrocarbon gases in the catalytic cracking reaction system is achieved by pressure expansion replacement and optional purging; preferably, the replacement gas replacement is completed when the hydrocarbon gas content in the gas discharged from the catalytic cracking reaction system is less than 0.2v%.

[0045] (3) After the replacement gas is replaced, the feed of the replacement gas is turned off; the coking gas is fed into the catalytic cracking reaction system as regeneration gas to regenerate the deactivated catalyst by coking. The gas generated by coking is preferably sent to the regeneration tail gas treatment unit; after coking is completed, the coking gas is replaced with replacement gas to replace the catalytic cracking reaction system.

[0046] The catalyst used in the above-mentioned catalytic cracking reaction is preferably regenerated using the catalyst regeneration system described in one of the objectives of this invention.

[0047] In the catalyst regeneration method described in this invention, preferably,

[0048] (1) When the catalytic cracking reaction is carried out in the catalytic cracking reactor of the catalytic cracking reaction unit, the material control valve A on the pipeline from the raw material feed unit to the catalytic cracking reaction unit is in the open state, and the material control valve B on the pipeline from the regeneration gas feed unit to the catalytic cracking reaction unit is in the closed state; and the material control valve C on the pipeline from the catalytic cracking reaction unit to the reaction product post-processing unit is in the open state, and the material control valve D on the pipeline from the catalytic cracking reaction unit to the regeneration tail gas treatment unit is in the closed state.

[0049] When the catalyst in the catalytic cracking reactor is deactivated and needs to be regenerated, material control valve A is closed to stop the feed of raw materials into the feed unit, and material control valve B is opened to allow the displacement gas to enter the catalytic cracking reactor. Then, the displacement gas and hydrocarbon gases (potentially emitted VOCs) in the catalytic cracking reactor are discharged to the reaction product post-treatment unit. Subsequently, the displacement gas content in the discharge gas before the compression unit in the reaction product post-treatment unit is detected by a displacement gas content detector. Preferably, in the reaction product post-treatment unit, the discharge gas passes sequentially through the reaction product cooler, the displacement gas content detector, the compression unit, and the separation unit.

[0050] (2) When the detected value of the replacement gas content exceeds the replacement gas content control value, close the material control valve C, stop the catalytic cracking reaction unit from discharging to the reaction product post-processing unit, and open the material control valve D to switch to discharging to the regeneration tail gas treatment unit for tail gas treatment.

[0051] (3) After the replacement gas is replaced, the feed of the replacement gas is turned off; the replacement gas is replaced with coke gas, and the coke gas is fed into the catalytic cracking reactor as regeneration gas to regenerate the deactivated catalyst. The gas generated by coke is preferably sent to the regeneration tail gas treatment unit; after the coke is finished, the coke gas is replaced with replacement gas to replace the catalytic cracking reaction unit.

[0052] In this invention, the catalyst bed does not experience a temperature rise, which can be considered as the end of coking.

[0053] In the catalyst regeneration method described in this invention, preferably,

[0054] The volumetric flow rate of the displacement gas feed is 0.1% to 3.0% of the volumetric flow rate of the catalytic cracking reaction feedstock, preferably 1.5% to 2.0%; and / or,

[0055] The displacement gas content is controlled to be no more than 2% by volume in the effluent gas of the catalytic cracking reaction unit, preferably 0.1% to 2.0%, and more preferably 0.5% to 1.0%.

[0056] In the catalyst regeneration method described in this invention, preferably,

[0057] The number of catalytic cracking reactors is one or more, and the catalytic cracking reactors are arranged in a switchable parallel configuration; preferably, there are two or more.

[0058] More preferably, when there are two or more catalytic cracking reactors, after the catalyst in the catalytic cracking reactor is deactivated, the feed from the raw material feeding unit is switched to the catalytic cracking reactor where the catalyst is working normally, and normal catalytic cracking reaction is carried out; the deactivated catalyst is regenerated according to the catalyst regeneration treatment method described above.

[0059] A third objective of this invention is to provide a catalyst regeneration system for catalytic cracking reactions as described in one objective of this invention, or a catalyst regeneration method for catalytic cracking reactions as described in another objective of this invention, for use in catalytic cracking reactions, preferably in olefin catalytic cracking reactions.

[0060] For the sake of accuracy and convenience, the process media within the catalytic cracking reactor, the auxiliary equipment and pipelines upstream of the catalytic cracking reactor connected to the regeneration gas feed pipeline, and the auxiliary equipment and pipelines downstream of the catalytic cracking reactor connected to the regeneration tail gas treatment unit, including reaction raw materials, reaction intermediates, and reaction products, are collectively referred to as "potential VOC emissions." Clearly, potential VOC emissions are the VOCs that require targeted treatment during catalyst regeneration in the catalytic cracking reactor. The total mass of potential VOC emissions is the maximum VOCs that the regeneration tail gas treatment unit needs to receive. The catalyst regeneration treatment system and method for the catalytic cracking reaction of this invention can effectively reduce the mass of VOCs entering the regeneration tail gas treatment unit, allowing only a portion of the potential VOC emissions to enter the regeneration tail gas treatment unit. The technical solution of this invention will be further explained below.

[0061] The catalyst regeneration system and method for catalytic cracking reactions of this invention, when the catalyst used in olefin catalytic cracking is deactivated and needs regeneration, firstly, the feedstock to the catalytic cracking reactor is cut off, and replacement gas is introduced through the regeneration gas feed unit as the regeneration gas feed into the catalytic cracking reactor. Simultaneously, the pipeline from the catalytic cracking reactor to the reaction product post-treatment unit is kept unobstructed, and the valve from the catalytic cracking reactor to the regeneration tail gas treatment unit is kept closed. Then, a replacement gas, such as nitrogen, is introduced into the catalytic cracking reactor and its auxiliary systems. Because the nitrogen pressure is higher than that of the catalytic cracking reactor and its downstream pressure, the process medium in the catalytic cracking reactor will flow downstream under the impetus of nitrogen and enter the reaction product post-treatment unit. At the same time, due to the thermal motion of molecules, nitrogen diffuses in the process medium as it flows downstream along the pipeline, resulting in mixing of nitrogen and the process medium, creating a mixed gas section with uneven nitrogen concentration. Initially, nitrogen is only present at the nitrogen inlet, and the process medium entering the reaction product post-treatment unit does not contain nitrogen. Over time, nitrogen will appear in the process medium entering the reaction product post-treatment unit, and the nitrogen content will gradually increase over time.

[0062] Then, an online analyzer is used to obtain the nitrogen content at the inlet of the compression unit in the reaction product post-treatment unit. This nitrogen content is used as a control variable to automatically control the opening or closing of the regeneration gas flow regulating valve on the pipeline from the regeneration gas feed unit to the inlet of the catalytic cracking reactor, thereby automatically cutting off the replacement gas, such as nitrogen. In this method, before the nitrogen content at the compression unit inlet reaches the control value, the process media remaining in the regeneration system, i.e., the potential emission VOCs, will continuously enter the reaction product post-treatment unit, rather than the regeneration tail gas treatment unit. The regeneration gas flow regulating valve will only automatically close when the nitrogen content reaches the control value.

[0063] Afterwards, the pipeline from the catalytic cracking reactor to the reaction product post-processing system can be shut off, while the material pipeline from the catalytic cracking reactor outlet to the regeneration tail gas treatment unit can be opened. Then, the residual VOCs in the system are discharged to the regeneration tail gas treatment unit using optional purging, pressure purging, or other conventional methods. Subsequently, the catalyst is regenerated by coking and then replaced with nitrogen using existing conventional methods to complete the catalyst regeneration operation. In summary, compared to existing technologies, the catalyst regeneration system and method for the catalytic cracking reaction of this invention ensures that a portion of the process media in the regeneration system first enters the reaction product post-processing unit, with only a portion entering the regeneration tail gas treatment unit, resulting in a reduction of over 90% in the total amount of VOCs requiring treatment.

[0064] In addition, when applying the method of this invention to treat the olefin catalytic cracking regeneration tail gas, two indicators require special attention. One important indicator is the flow rate of the replacement gas, such as nitrogen, and the other is the volumetric nitrogen content in the process medium entering the reaction product post-treatment unit. This is monitored by a replacement gas content detector (such as a nitrogen content detector) installed at the inlet of the compression unit. Of these two indicators, the most important control indicator is the flow rate of the replacement gas, such as nitrogen. The nitrogen flow rate is important because the nitrogen content in the reaction products will affect the stable operation of the compression unit (compressor) in the reaction product post-treatment unit. As nitrogen is continuously injected into the catalytic cracking reactor, the process medium in the catalytic cracking reactor is pushed into the downstream pipeline, and the nitrogen concentration therein gradually increases. This nitrogen-containing medium from the catalytic cracking reactor will merge with the reaction products from the catalytic cracking reactor and enter the compression unit together. The average molecular weight of the mixed process medium is generally between 40 and 60, while the molecular weight of nitrogen is only 28. Therefore, if the nitrogen content in the mixed process medium is too high, the molecular weight of the gas drawn into the compressor will be too low. Under the condition that the compressor intake pressure and flow rate remain unchanged, the compressor outlet pressure will not reach the design value. Therefore, it is necessary to limit the nitrogen content in the mixed process medium. Studies have shown that when the nitrogen volume content is 2%, to achieve the same outlet pressure, the compressor power increases by about 5%, and the average molecular weight of the compressor intake medium decreases by 0.6; when the nitrogen volume content is 3.8%, to achieve the same outlet pressure, the compressor power increases by about 10%, and the average molecular weight of the compressor intake medium decreases by 1.0. Therefore, in order to ensure the normal and stable operation of the compressor, it is necessary to control the nitrogen volume content in the mixed process medium to not exceed 2%, preferably 0.1% to 2.0%, and more preferably 0.5% to 1.0%.

[0065] However, the volumetric nitrogen content in the mixed process medium is also related to the nitrogen injection flow rate. If the nitrogen injection flow rate is too low, the time required for the gas in the catalytic cracking reactor to be replaced with nitrogen will be too long, prolonging the switching and regeneration time of the catalytic cracking reactor and resulting in low replacement efficiency. If the nitrogen flow rate is too high, nitrogen will form a long mixing section in the pipeline system (referring to a pipe section with a nitrogen volume concentration of 10% to 90%). The higher the nitrogen flow rate in the pipeline, the longer the mixing section, which will lead to a significant reduction in the amount of potential VOCs entering the downstream reaction product after-treatment system under the same nitrogen content control value.

[0066] Therefore, while ensuring the normal operation of the compression unit, the controlled value of the nitrogen volume content at the inlet of the compression unit should be as large as possible, while the nitrogen flow rate should be appropriately small, thereby balancing replacement efficiency and controlling the amount of nitrogen entering the downstream. Studies have shown that the nitrogen volume flow rate should preferably be below 3.0% of the normal volume flow rate of the catalytic cracking reaction feedstock, preferably below 2.0%. This ensures that the nitrogen volume content in the mixed gas entering the compression unit inlet does not exceed 2%, preferably 0.1% to 2.0%, and more preferably 0.5% to 1.0%.

[0067] In summary, this invention fundamentally controls the amount of process medium discharged into the regeneration tail gas treatment unit during the nitrogen replacement process in the catalytic cracking reaction system, effectively solving the problems of material waste and large tail gas treatment volume in the olefin catalytic cracking regeneration process of the prior art. Therefore, the catalyst regeneration treatment system and method for catalytic cracking reaction provided by this invention has the advantages of reducing material waste and lowering the tail gas treatment volume in the olefin catalytic cracking regeneration process.

[0068] Existing technologies can address reducing exhaust emissions or material waste from multiple angles, such as improving catalysts, enhancing stability, reducing coking, and decreasing regeneration cycles, thereby reducing regeneration exhaust emissions. However, the main focus of existing technologies is clearly on catalyst improvement. This invention, however, does not address the catalyst itself but innovatively adjusts the process. By improving the structure of the catalyst regeneration system, controlling the flow rate of the displacement gas entering the catalytic cracking reaction unit, and controlling the displacement gas content in the effluent gas from the catalytic cracking reaction unit, this invention allows materials with lower displacement gas content in the effluent gas to be recycled in the reaction product post-processing unit, while materials with higher displacement gas content are recycled in the regeneration exhaust gas treatment unit. Compared to existing methods that directly send all exhaust gas from the catalyst regeneration process to the regeneration exhaust gas treatment unit, this invention effectively reduces exhaust emissions and material waste. Therefore, while the overall process of this invention appears simple, it is actually very ingenious, and would have been difficult for someone skilled in the art to conceive of before the technical solution of this invention was disclosed.

[0069] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values; these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. In the following, various technical solutions can, in principle, be combined with each other to obtain new technical solutions, which should also be considered as specifically disclosed herein.

[0070] Compared with the prior art, the present invention has at least the following advantages:

[0071] The catalyst regeneration system for the catalytic cracking reaction of the present invention effectively reduces the mass of VOCs entering the regeneration tail gas treatment unit, reduces carbon dioxide emissions, and is environmentally friendly.

[0072] The catalyst regeneration system for the catalytic cracking reaction of the present invention can recover some of the potentially emitted VOCs and reduce material loss.

[0073] The catalyst regeneration system for the catalytic cracking reaction of the present invention reduces the processing load of the regeneration tail gas treatment unit, thereby saving energy and reducing consumption.

[0074] The catalyst regeneration system for the catalytic cracking reaction of the present invention analyzes the content of the replacement gas (such as nitrogen content) online using a replacement gas content detector (such as nitrogen), which can realize automatic control of the tail gas generated during the replacement gas replacement (such as nitrogen replacement) process, and is simple and convenient to operate.

[0075] In summary, the catalyst regeneration system and method for catalytic cracking reaction of the present invention can achieve good technical results. Attached Figure Description

[0076] Figure 1 This is a schematic diagram of the catalyst regeneration system for the catalytic cracking reaction of the present invention;

[0077] Figure 2 This is a schematic diagram of the reaction product post-processing unit of the present invention.

[0078] Explanation of reference numerals in the attached figures:

[0079] 1-Material control switch A1, 2-Material control switch B1, 3-Material control switch C1, 4-Material control switch D1, 5-Material control switch A2, 6-Material control switch B2, 7-Material control switch C2, 8-Material control switch D2, 9-Regenerated gas flow regulating valve; 10-Raw material feeding unit; 30-Regenerated gas feeding unit; 21-First catalytic cracking reactor, 22-Second catalytic cracking reactor; 40-Reaction product post-processing unit; 41-Reaction product cooler, 42-Purge gas content detector, 43-Compression unit, 44-Separation unit; 50-Regenerated tail gas treatment unit.

[0080] Figure 1 The dashed line represents the material transport pipeline for regenerated gas, while the solid line represents the material transport pipeline in the catalytic cracking reaction process. Detailed Implementation

[0081] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0082] It should also be noted that the various specific technical features described in the following embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the various possible combinations will not be described separately in this invention.

[0083] Furthermore, various embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention. The resulting technical solutions are part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0084] Unless otherwise specified, the raw materials used in the examples and comparative examples are all disclosed in the prior art, such as those that can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0085] Example 1

[0086] The present invention provides a catalyst regeneration tail gas treatment system for catalytic cracking reactions (e.g., Figure 1 As shown, the system includes a regeneration gas feed unit 30, a catalytic cracking reaction unit, a reaction product post-processing unit 40, a regeneration tail gas treatment unit 50, and a raw material feed unit 10; the regeneration gas includes replacement gas and coke combustion gas; the raw material feed unit 10 is the feed unit for the raw materials used in the catalytic cracking reaction; the reaction product post-processing unit 40 is the post-processing unit for the reaction products of the catalytic cracking reaction; the catalytic cracking reaction unit includes a catalytic cracking reactor filled with a catalyst; the catalytic cracking reactor is a fixed-bed reactor; and the regeneration tail gas treatment unit is a flare.

[0087] The number of catalytic cracking reactors is at least two. In this embodiment, it includes a first catalytic cracking reactor 21 and a second catalytic cracking reactor 22.

[0088] The outlet of the raw material feeding unit 10 is connected to the inlet of the first catalytic cracking reactor 21 and the second catalytic cracking reactor 22 respectively, and the connecting pipeline between the raw material feeding unit 10 and the first catalytic cracking reactor 21 and the second catalytic cracking reactor 22 is respectively equipped with a material control switch A1 1 and a material control switch A2 5.

[0089] The outlet of the regenerated gas feed unit 30 is connected to the inlet of the first catalytic cracking reactor 21 and the second catalytic cracking reactor 22 respectively, and the connecting pipeline between the regenerated gas feed unit and the first catalytic cracking reactor 21 and the second catalytic cracking reactor 22 is respectively equipped with a material control switch B1 2 and a material control switch B2 6.

[0090] The outlets of the first catalytic cracking reactor 21 and the second catalytic cracking reactor 22 are respectively connected to the inlet of the reaction product post-processing unit 40, and material control switches C13 and C27 are respectively provided on the connecting pipelines between the first catalytic cracking reactor 21, the second catalytic cracking reactor 22 and the reaction product post-processing unit.

[0091] The outlets of the first catalytic cracking reactor 21 and the second catalytic cracking reactor 22 are respectively connected to the inlet of the regeneration tail gas treatment unit 50, and material control switches D1 4 and D2 8 are respectively provided on the connecting pipelines between the first catalytic cracking reactor 21, the second catalytic cracking reactor 22 and the regeneration tail gas treatment unit 50.

[0092] The material control switches described above are selected from existing common switches, including shut-off valves, regulating valves, and blind flanges. As can be seen from the above connection relationships, the first catalytic cracking reactor 21 and the second catalytic cracking reactor 22 are connected in parallel and arranged in a switchable configuration.

[0093] The reaction product post-processing unit (such as...) Figure 2 The device (shown) includes a reaction product cooler 41, a displacement gas content detector 42, a compression unit 43, and a separation unit 44; the compression unit 43 is connected between the reaction product cooler 41 and the separation unit 44; the displacement gas content detector 42 is installed on the inlet pipe of the compression unit 43; the feed port of the reaction product cooler is connected to the discharge port of the catalytic cracking reaction unit through a pipeline.

[0094] In addition to material control switches B1 and B2, the outlet pipeline of the regenerated gas feeding unit 30 is also equipped with a regenerated gas flow regulating valve 9; the displacement gas content detector 42 is electrically connected to the regenerated gas flow regulating valve 9; the displacement gas content detector is an online gas composition analyzer.

[0095] The operation method of the catalyst regeneration tail gas treatment system utilizing the catalytic cracking reaction of the present invention is as follows:

[0096] Assuming the first catalytic cracking reactor 21 is operating and the second catalytic cracking reactor 22 has finished regenerating, the operating status of the first catalytic cracking reactor 21 is as follows: material control switches A11 and C13 are open, and material control switches corresponding to numbers 2, 4-8 are all closed. The reaction feed enters the first catalytic cracking reactor 21 via material control switch A11, and the effluent from the first catalytic cracking reactor 21 enters the reaction product post-processing unit 40 via material control switch C13. When the catalyst needs regeneration due to gradual deactivation in the first catalytic cracking reactor 21, material control switch A11 is first closed, then material control switch B12 is opened, and nitrogen flow is controlled by regeneration gas flow regulating valve 9 to introduce nitrogen into the first catalytic cracking reactor 21. When the analysis results of the replacement gas content detector 42 show that the nitrogen volume concentration in the effluent gas of the first catalytic cracking reactor 21 reaches 2%, material control switch C13 is closed, and material control switch D14 is opened. Then, by pressurizing and replacing with nitrogen, the potential VOCs (hydrocarbon gases) emitted from the first catalytic cracking reactor 21 are replaced. Nitrogen replacement is completed when the hydrocarbon gas content in the effluent from the catalytic cracking reaction system is below 0.2 vol%. After nitrogen replacement, the nitrogen feed is shut off. The coking gas (a mixture of air and nitrogen, with an oxygen content of 0.5 vol% to 5 vol%) is fed into the catalytic cracking reaction system as regeneration gas to regenerate the deactivated catalyst. If there is no temperature rise in the catalyst bed, coking is considered complete. The gas produced from coking is sent to the regeneration tail gas treatment unit. After coking, the coking gas is replaced with replacement gas to perform nitrogen replacement on the catalytic cracking reaction system, completing the catalyst regeneration operation. This invention performs a conventional catalyst regeneration operation on the first catalytic cracking reactor 21.

[0097] While closing material control switch A1, open material control switches A2 5 and C2 7 to start the second catalytic cracking reactor 22. This achieves continuous production by using one reactor for catalytic cracking and another for catalyst regeneration. The regeneration process of the second catalytic cracking reactor 22 is similar and will not be described further.

[0098]

Example 2

[0099] A chemical plant that processes methanol to olefins and produces C4 as a byproduct uses the following method: Figure 1 The catalyst regeneration system and method shown are used for catalyst regeneration in catalytic cracking reactions. Before the catalyst in the catalytic cracking reactor is deactivated, the C4 feedstock undergoes olefin catalytic cracking in the reactor, converting it into reaction products such as ethylene and propylene. The volumetric flow rate of the feedstock for the catalytic cracking reaction is 30,000 m³ / s. 3 / hr, the volume of the catalytic cracking reactor and its auxiliary pipelines is approximately 206m³.3 When the catalyst in the catalytic cracking reactor becomes deactivated, it needs to be regenerated. The first step is nitrogen purging, which involves replacing the process medium in the catalytic cracking reactor with nitrogen. To do this, the feedstock for the catalytic cracking reaction must be shut off, and the nitrogen feed line opened. The nitrogen flow rate is then set to 30 m³ / s using the regeneration gas flow control valve. 3 / hr means that the nitrogen flow rate is 0.1% of the volumetric flow rate of the feedstock in the catalytic cracking reaction. In the catalytic cracking reaction system of nitrogen replacement process, the effluent gas is first cooled by the cooler in the catalytic cracking reaction post-processing unit, and then the nitrogen content in the mixed gas formed by the reaction products (hydrocarbon gas) and nitrogen in the catalytic cracking reaction is detected by the online chromatograph (nitrogen content detector) at the inlet of the compression unit. Then it enters the compression unit and the distillation separation unit for material separation.

[0100] When the online chromatograph shows that the nitrogen volume content in the mixed gas at the inlet of the compression unit reaches 0.1%, the pipeline of the potential emission VOCs + nitrogen mixture in the catalytic cracking reactor to the post-treatment unit of the catalytic cracking reaction is cut off, and the pipeline of the potential emission VOCs + nitrogen mixture in the catalytic cracking reactor to the regeneration tail gas treatment unit is opened. That is, the destination of the potential emission VOCs + nitrogen mixture is switched to the regeneration tail gas treatment unit, i.e., incineration in the incinerator. At the same time, the nitrogen feed pipeline is cut off to perform nitrogen pressure replacement. After the potential emission VOCs in the catalytic cracking reactor and its upstream and downstream auxiliary systems are replaced (i.e., the first nitrogen replacement), the nitrogen is replaced with coke gas (coke gas is a mixture of air and nitrogen; the oxygen content in the coke gas is 2v%) and introduced into the catalytic cracking reactor for catalyst coke regeneration. After coke is completed, the coke gas is replaced with nitrogen again for nitrogen replacement (i.e., the second nitrogen replacement), and finally the regenerated catalyst is obtained. The olefin catalytic cracking reactor uses shape-selective molecular sieve catalysts, and the catalyst regeneration cycle is 5 days.

[0101] In this embodiment, the first nitrogen purging process takes approximately 7.06 hours. Compared to the operation of directly sending the reaction products in the catalytic cracking reactor to the incinerator during the first nitrogen purging under the same process, VOC emissions can be reduced by approximately 99%. Compared to the prior art, the present invention effectively reduces the amount of regeneration tail gas generated during the first nitrogen purging. At the same time, the first part of the regeneration tail gas generated during the first nitrogen purging is sent to the catalytic cracking reaction post-treatment unit, which can be used to recover and separate polymer-grade ethylene and polymer-grade propylene products, which also effectively reduces material waste.

[0102]

Example 3

[0103] The same apparatus and process route as in Example 2 were used, except that the nitrogen flow rate was set to 300 m³ / s. 3 / hr, which is 1.0% of the raw material feed flow rate. When the online chromatograph shows that the nitrogen volume content in the material at the inlet of the compression unit reaches 0.5%, the destination of the regeneration tail gas is switched to the incinerator.

[0104] In this embodiment, the first nitrogen purging process takes about 0.65 hours. Compared with the operation of sending the reaction products in the catalytic cracking reactor directly to the incinerator during the first nitrogen purging under the same process, VOC emissions can be reduced by about 95%.

[0105]

Example 4

[0106] The same apparatus and process route as in Example 2 were used, except that the nitrogen flow rate was set to 450 m³ / h. 3 / hr, which is 1.5% of the raw material feed flow rate. When the online chromatograph shows that the nitrogen content in the reactor outlet material reaches 0.5%, the regeneration tail gas is switched to the incinerator. After the hydrocarbon media in the reactor and its upstream and downstream auxiliary systems have been replaced, air is introduced for coke combustion regeneration.

[0107] In this embodiment, the nitrogen treatment time is approximately 0.35 hours, and the potential VOC emissions are reduced by approximately 95%.

[0108] In this embodiment, the first nitrogen purging process takes about 0.35 hours. Compared with the operation of sending the reaction products in the catalytic cracking reactor directly to the incinerator during the first nitrogen purging under the same process, VOC emissions can be reduced by about 95%.

[0109]

Example 5

[0110] The same apparatus and process route as in Example 2 were used, except that the nitrogen flow rate was set to 150 m³ / h. 3 / hr, which is 0.5% of the raw material feed flow rate. When the online chromatograph shows that the nitrogen content in the reactor outlet material reaches 0.25%, the regeneration tail gas is switched to the incinerator. After the hydrocarbon media in the reactor and its upstream and downstream auxiliary systems have been replaced, air is introduced for coke combustion regeneration.

[0111] In this embodiment, the first nitrogen purging process takes about 1.28 hours. Compared with the operation of sending the reaction products in the catalytic cracking reactor directly to the incinerator during the first nitrogen purging under the same process, VOC emissions can be reduced by about 95%.

[0112]

Example 6

[0113] The same apparatus and process route as in Example 2 were used, except that the nitrogen flow rate was set to 150 m³ / h.3 / hr, which is 0.5% of the raw material feed flow rate. When the online chromatograph shows that the nitrogen content in the reactor outlet material reaches 0.45%, the regeneration tail gas is switched to the incinerator. After the hydrocarbon media in the reactor and its upstream and downstream auxiliary systems have been replaced, air is introduced for coke combustion regeneration.

[0114] In this embodiment, the first nitrogen purging process takes about 1.32 hours. Compared with the operation of sending the reaction products in the catalytic cracking reactor directly to the incinerator during the first nitrogen purging under the same process, VOC emissions can be reduced by about 96%.

[0115]

Example 7

[0116] use Figure 1 Using the same equipment and process route, the volumetric flow rate of the reaction feed is approximately 45,000 m³. 3 / hr, the reactor and its auxiliary piping volume is approximately 420m³. 3 Set the nitrogen flow rate to 360 m³ / h. 3 / hr, which is 0.80% of the raw material feed flow rate. When the online chromatograph shows that the nitrogen content in the reactor outlet material reaches 0.1%, the regeneration tail gas is switched to the incinerator. After the hydrocarbon media in the reactor and its upstream and downstream auxiliary systems have been replaced, air is introduced for coke combustion regeneration.

[0117] In this embodiment, the first nitrogen purging process takes about 1.08 hours. Compared with the operation of sending the reaction products in the catalytic cracking reactor directly to the incinerator during the first nitrogen purging under the same process, VOC emissions can be reduced by about 94%.

[0118]

Example 8

[0119] The same apparatus and process route as in Example 2 were used, except that the nitrogen flow rate was set to 600 m³ / s. 3 / hr, which is 2.0% of the raw material feed flow rate. When the online chromatograph shows that the nitrogen content in the reactor outlet material reaches 1.0%, the regeneration tail gas is switched to the incinerator. After the hydrocarbon media in the reactor and its upstream and downstream auxiliary systems have been replaced, air is introduced for coke combustion regeneration.

[0120] In this embodiment, the first nitrogen purging process takes about 0.33 hours. Compared with the operation of sending the reaction products in the catalytic cracking reactor directly to the incinerator during the first nitrogen purging under the same process, VOC emissions can be reduced by about 95%.

[0121]

Example 9

[0122] The same apparatus and process route as in Example 2 were used, except that the nitrogen flow rate was set to 900 m³ / s.3 / hr, which is 3.0% of the raw material feed flow rate. When the online chromatograph shows that the nitrogen content in the reactor outlet material reaches 1.0%, the regeneration tail gas is switched to the incinerator. After the hydrocarbon media in the reactor and its upstream and downstream auxiliary systems have been replaced, air is introduced for coke combustion regeneration.

[0123] In this embodiment, the first nitrogen purging process takes about 0.22 hours. Compared with the operation of sending the reaction products in the catalytic cracking reactor directly to the incinerator during the first nitrogen purging under the same process, VOC emissions can be reduced by about 96%.

[0124] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A catalyst regeneration system for a catalytic cracking reaction, comprising a regeneration gas feeding unit, a raw material feeding unit, a catalytic cracking reaction unit, a reaction product post-processing unit, and a regeneration tail gas treatment unit; wherein the regeneration gas comprises displacement gas and coke burner gas; in, The feed inlet of the catalytic cracking reaction unit is switched between the regeneration gas feed unit and the raw material feed unit; The outlet of the catalytic cracking reaction unit is switched between the reaction product post-processing unit and the regeneration tail gas treatment unit. The reaction product post-processing unit includes a compression unit, and a displacement gas content detector is installed on the inlet pipe of the compression unit. The displacement gas content detector is an online gas composition analyzer. The displacement gas content detector detects the displacement gas content in the effluent gas before the compression unit in the reaction product post-processing unit. When the detected displacement gas content exceeds the displacement gas content control value, the gas discharge from the catalytic cracking reaction unit to the reaction product post-processing unit is stopped, and the gas from the catalytic cracking reaction unit is switched to the regeneration tail gas treatment unit for tail gas treatment. The displacement gas content control value refers to the volume content of displacement gas in the effluent gas of the catalytic cracking reaction unit. The displacement gas content control value does not exceed 2%. The displacement gas is selected from nitrogen. The displacement gas content detector is a nitrogen content detector. The catalyst for the catalytic cracking reaction is a catalyst used for the catalytic cracking of olefins.

2. The catalyst regeneration system according to claim 1, characterized in that: All of the aforementioned switching connections include switching connections by setting material control switches on the corresponding connection pipelines.

3. The catalyst regeneration system according to claim 2, characterized in that: The material control switch includes a shut-off valve, a regulating valve, and a blind flange.

4. The catalyst regeneration system according to claim 3, characterized in that: The outlet of the raw material feeding unit is connected to the inlet pipeline of the catalytic cracking reaction unit, and a material control switch A is provided on the connecting pipeline between the two. The outlet of the regenerated gas feed unit is connected to the inlet pipeline of the catalytic cracking reaction unit, and a material control switch B is installed on the connecting pipeline between the two. The outlet of the catalytic cracking reaction unit is connected to the inlet of the reaction product post-processing unit, and a material control switch C is provided on the connecting pipeline between the two. The outlet of the catalytic cracking reaction unit is connected to the inlet of the regeneration tail gas treatment unit, and a material control switch D is provided on the connecting pipeline between the two.

5. The catalyst regeneration system according to claim 4, characterized in that: In addition to the material control switch B, the outlet pipeline of the regenerated gas feeding unit is also equipped with a regenerated gas flow regulating valve; the displacement gas content detector is electrically connected to the regenerated gas flow regulating valve.

6. The catalyst regeneration system according to claim 1, characterized in that: The burnt gas is a mixture of air and nitrogen.

7. The catalyst regeneration system according to claim 6, characterized in that: The oxygen volume content in the coking gas is 0.5v%~5v%.

8. The catalyst regeneration system according to claim 1, characterized in that: The reaction product post-processing unit also includes a reaction product cooler and a separation unit; A compression unit is connected between the reaction product cooler and the separation unit; the inlet of the reaction product cooler is connected to the outlet of the catalytic cracking reaction unit via a pipeline.

9. The catalyst regeneration system according to claim 8, characterized in that: The separation unit is a distillation column.

10. The catalyst regeneration system according to claim 4, characterized in that: The catalytic cracking reaction unit includes a catalytic cracking reactor filled with a catalyst, and the number of the catalytic cracking reactors is one or more; the catalytic cracking reactors are connected in parallel and arranged in a switchable manner.

11. The catalyst regeneration system according to claim 10, characterized in that: The number of catalytic cracking reactors is at least two.

12. The catalyst regeneration system according to claim 10, characterized in that: The outlet of the raw material feeding unit is connected to the inlet of any catalytic cracking reactor, and a material control switch A is provided on the connecting pipeline between the raw material feeding unit and any catalytic cracking reactor. The outlet of the regenerated gas feed unit is connected to the inlet of any catalytic cracking reactor, and a material control switch B is provided on the connecting pipeline between the regenerated gas feed unit and any catalytic cracking reactor. The outlet of any catalytic cracking reactor is connected to the inlet of the reaction product post-processing unit, and a material control switch C is provided on the connecting pipeline between any catalytic cracking reactor and the reaction product post-processing unit. The outlet of any catalytic cracking reactor is connected to the inlet of the regeneration tail gas treatment unit, and a material control switch D is provided on the connecting pipeline between any catalytic cracking reactor and the regeneration tail gas treatment unit.

13. The catalyst regeneration system according to claim 10, characterized in that: The catalytic cracking reactor is a fixed-bed reactor; and / or The regenerated exhaust gas treatment unit includes a flare and / or an incinerator.

14. A method for regenerating a catalyst in a catalytic cracking reaction, comprising the following steps: (1) When the catalyst used in the catalytic cracking reaction is deactivated, the feed of the reaction raw material in the catalytic cracking reaction unit is stopped, and the replacement gas is fed into the catalytic cracking reaction unit as the regeneration gas. The gas in the catalytic cracking reaction unit is discharged to the reaction product post-processing unit. The content of replacement gas in the gas discharged from the catalytic cracking reaction unit is detected before the feed inlet of the compression unit in the reaction product post-processing unit. (2) When the detected value of the displacement gas content exceeds the displacement gas content control value, the gas discharge from the catalytic cracking reaction unit to the reaction product post-processing unit is stopped, and the gas discharge from the catalytic cracking reaction unit is switched to the regeneration tail gas treatment unit for tail gas treatment; the displacement gas replaces the hydrocarbon gas in the catalytic cracking reaction unit through pressure displacement and optional purging; the displacement gas content control value refers to the displacement gas volume content in the discharge gas of the catalytic cracking reaction unit; the displacement gas content control value does not exceed 2%; the displacement gas is selected from nitrogen. (3) After the replacement gas is replaced, the feed of the replacement gas is turned off; the coking gas is fed into the catalytic cracking reaction unit as the regeneration gas to regenerate the deactivated catalyst. The catalyst for catalytic cracking reaction is regenerated using the catalyst regeneration system described in any one of claims 1-13.

15. The catalyst regeneration method according to claim 14, characterized in that: Step (2): When the volume content of hydrocarbon gas in the gas discharged from the catalytic cracking reaction unit is less than 0.2v%, the replacement gas replacement is completed; Step (3): The gas generated by burning is sent to the regeneration tail gas treatment unit.

16. The catalyst regeneration method according to claim 14, characterized in that: (1) When the catalytic cracking reaction is carried out in the catalytic cracking reactor of the catalytic cracking reaction unit, the material control valve A on the pipeline from the raw material feed unit to the catalytic cracking reaction unit is in the open state, and the material control valve B on the pipeline from the regeneration gas feed unit to the catalytic cracking reaction unit is in the closed state; and the material control valve C on the pipeline from the catalytic cracking reaction unit to the reaction product post-processing unit is in the open state, and the material control valve D on the pipeline from the catalytic cracking reaction unit to the regeneration tail gas treatment unit is in the closed state. When the catalyst in the catalytic cracking reactor is deactivated and needs to be regenerated, the material control valve A is closed to stop the raw material feeding unit, and the material control valve B is opened to allow the replacement gas to enter the catalytic cracking reactor. Then the replacement gas and the hydrocarbon gas in the catalytic cracking reactor are discharged to the reaction product post-processing unit. Subsequently, the replacement gas content in the discharge gas before the compression unit in the reaction product post-processing unit is detected by the replacement gas content detector. (2) When the detected value of the replacement gas content exceeds the replacement gas content control value, close the material control valve C, stop the catalytic cracking reaction unit from discharging to the reaction product post-processing unit, and open the material control valve D to switch to discharging to the regeneration tail gas treatment unit and enter the regeneration tail gas treatment unit for tail gas treatment. (3) After the replacement gas is replaced, the feed of the replacement gas is turned off; the replacement gas is replaced with coke gas, and the coke gas is fed into the catalytic cracking reactor as regeneration gas to regenerate the deactivated catalyst. The gas generated by coke is sent to the regeneration tail gas treatment unit; after the coke is finished, the coke gas is replaced with replacement gas to replace the catalytic cracking reaction unit.

17. The catalyst regeneration method according to claim 16, characterized in that: Step (1): In the reaction product post-processing unit, the effluent gas passes sequentially through the reaction product cooler, the displacement gas content detector, the compression unit, and the separation unit.

18. The catalyst regeneration method according to any one of claims 14-17, characterized in that: The volumetric flow rate of the displacement gas feed is 0.1% to 3.0% of the volumetric flow rate of the feedstock for the catalytic cracking reaction.

19. The catalyst regeneration method according to claim 18, characterized in that: The volumetric flow rate of the displacement gas feed is 1.5% to 2.0% of the volumetric flow rate of the catalytic cracking reaction feedstock; The controlled value of the replacement gas content is between 0.1% and 2.0%.

20. The catalyst regeneration method according to claim 19, characterized in that: The controlled value of the replacement gas content is between 0.5% and 1.0%.

21. The catalyst regeneration method according to claim 16, characterized in that: The number of catalytic cracking reactors is more than one, and the catalytic cracking reactors are arranged in a switchable parallel configuration.

22. The catalyst regeneration method according to claim 21, characterized in that: The number of catalytic cracking reactors is two or more.

23. The catalyst regeneration method according to claim 22, characterized in that: After the catalyst in the catalytic cracking reactor is deactivated, the feed from the feed unit is switched to the catalytic cracking reactor where the catalyst is working normally, and the normal catalytic cracking reaction is carried out; the deactivated catalyst is regenerated according to the catalyst regeneration treatment method described in any one of claims 14-17.

24. The application of a catalyst regeneration system according to any one of claims 1-13 in olefin catalytic cracking reactions.

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