High-density rapid fluidized bed reactor, methanol-to-olefin device and methanol-to-olefin method

Abstract

The invention discloses a high-density rapid fluidized bed reactor, a methanol-to-olefin device and a methanol-to-olefin method. The device comprises a high-density fast fluidized bed reactor and a fluidized bed regenerator. According to the high-density rapid fluidized bed reactor, the circulation strength of a catalyst flowing from the catalyst retention zone to the reaction zone reaches up to 500-1000 kg / (m < 2 >. S), so that the bed density of the reaction zone is improved, and high bed density is obtained under the condition of high apparent linear velocity. According to the method, one of methanol or dimethyl ether or a mixture of methanol and dimethyl ether is used as a raw material to produce ethylene, propylene and butylene, the yield of propylene and butylene can be increased by recycling ethylene, the yield of butylene can be increased by recycling propylene, and flexible adjustment of distribution of ethylene, propylene and butylene is realized. The sum of the contents of ethylene, propylene and butylene in the product is greater than or equal to 90% wt, and the potential content of alpha-butylene in the product can reach 57% wt.

Description

Technical Field

[0001] This application relates to the technical field of chemical catalysis, and particularly to a high-density fast fluidized bed reactor, a methanol-to-olefins device and a method thereof. Background Art

[0002] Olefins are important basic organic chemical raw materials and the cornerstone of the modern chemical industry. Traditional production technologies strongly rely on petroleum resources. Therefore, it is of great strategic significance to use China's relatively rich coal resources to replace petroleum resources.

[0003] The technical routes for olefin production mainly include steam cracking of naphtha to produce olefins, methanol-to-olefins, propane dehydrogenation to produce propylene, and alkane cracking to produce olefins, etc. Light olefins are very reactive and prone to polymerization, alkylation, aromatization and other reactions, generating by-products and reducing the yield of light olefins.

[0004] The methanol-to-olefins (MTO) technology aims at ethylene and propylene as target products. Methanol is converted into a mixture containing components such as ethylene, propylene, butene, pentene and alkanes under the action of a molecular sieve catalyst. In 2010, the Shenhua Baotou methanol-to-olefins plant using the DMTO technology developed by the Dalian Institute of Chemical Physics, Chinese Academy of Sciences was completed and put into production. This is the world's first industrial application of the MTO technology. As of 2023, 16 sets of DMTO industrial plants have been put into production, and the total low-carbon olefin production capacity is about 9.3 million tons / year. Taking the DMTO technology as an example, the carbon-based selectivity of ethylene and propylene is about 80% wt, and the selectivity of butene and pentene is about 15% wt.

[0005] In recent years, with the development of the high-end polyolefin industry, the demand for α-butene has increased rapidly year by year. Flexibly regulating the product distribution of the methanol-to-olefins technology and increasing the production of α-butene have become new market demands. Summary of the Invention

[0006] In view of this, this application provides a high-density fast fluidized bed reactor, a methanol-to-olefins device and a method thereof, and the main purpose is to solve the technical problem of low α-butene production in methanol-to-olefins.

[0007] The methanol-to-olefins technology uses SAPO molecular sieve catalysts. According to the hydrocarbon pool mechanism, methanol is converted into products such as ethylene and propylene through the aromatic cycle or olefin cycle in the molecular sieve catalyst. The main reactions include:

[0008] CH3OH → C2H4 + C3H6 (1)

[0009] C2H4 + CH3OH → C3H6 (2)

[0010] C3H6 + CH3OH → C4H8 (3)

[0011] C4H8 + CH3OH → C5H 10 (4)

[0012] Reactions (1) and (2) produce ethylene and propylene. Reactions (2), (3) and (4) show that small molecular olefins are relatively active, and the number of carbon atoms in the molecule can be further increased through alkylation reactions to convert into olefin molecules with a larger number of carbon atoms.

[0013] The SAPO molecular sieve catalyst is a shape-selective catalyst, and the olefin molecules in the methanol-to-olefins product are mainly linear olefin molecules. Among them, the content of 1-butene (α-butene) and 2-butene in butene is greater than 95%. 2-butene can be converted into 1-butene through isomerization technology. Therefore, the potential content of α-butene (1-butene and 2-butene) in the butene product of the methanol-to-olefins technology is as high as 95%.

[0014] The methanol-to-olefins technology uses a fluidized bed reactor. Improving the production capacity of a single reactor is one of the core objectives in the development of methanol-to-olefins reactors. An effective way to increase the production capacity of a single reactor is to increase the superficial linear velocity of the fluidized bed reactor to achieve the purpose of increasing the feedstock feed rate. However, when increasing the superficial linear velocity, the bed density in the reaction zone of the fluidized bed reactor usually decreases significantly, and the catalyst inventory also decreases significantly, which in turn leads to a decrease in methanol conversion rate. That is, there is a negative correlation between the feedstock feed rate and the bed density in the fluidized bed reaction zone.

[0015] In order to increase the production of α-butene, on the one hand, the present application provides a high-density fast fluidized bed reactor; the high-density fast fluidized bed reactor includes a reactor outer shell, a reactor inner shell and a conveying pipe;

[0016] The high-density fast fluidized bed reactor includes a reactor outer shell, a reactor inner shell, a conveying pipe and a reactor heat exchanger;

[0017] At least a raw material inlet, a catalyst inlet, a gas-phase product outlet and a catalyst outlet are provided on the reactor outer shell;

[0018] The reactor outer shell encloses an internal area;

[0019] The reactor inner shell is located in the lower part of the internal area, and the area enclosed by the reactor inner shell is the reaction zone;

[0020] The conveying pipe is located in the upper middle part of the internal area, and the bottom of the conveying pipe is communicated with the reaction zone;

[0021] The area enclosed by the reactor outer shell and the conveying pipe is the gas-solid separation zone;

[0022] The delivery pipe is provided with an outlet, and the delivery pipe communicates with the gas-solid separation zone;

[0023] The annular area enclosed by the reactor outer shell and the reactor inner shell is the catalyst residence zone;

[0024] The bottom of the reaction zone communicates with the bottom of the catalyst residence zone;

[0025] The catalyst residence zone communicates with the gas-solid separation zone and is located below the gas-solid separation zone;

[0026] The reactor heat exchanger is located in the catalyst residence zone.

[0027] Optionally, the high-density fast fluidized bed reactor includes a catalyst distribution pipe, a fluidizing steam distributor, and a raw material distributor;

[0028] The catalyst distribution pipe passes through the reactor inner shell to communicate the catalyst residence zone and the reaction zone;

[0029] The fluidizing steam distributor is arranged at the bottom of the catalyst residence zone;

[0030] The raw material distributor is arranged at the bottom of the reaction zone.

[0031] Optionally, through holes are formed on the lower surface of the catalyst distribution pipe.

[0032] Optionally, the high-density fast fluidized bed reactor includes a first gas-solid separation device and a second gas-solid separation device;

[0033] The first gas-solid separation device and the second gas-solid separation device are located in the gas-solid separation zone;

[0034] The inlet of the first gas-solid separation device communicates with the outlet of the delivery pipe;

[0035] The catalyst outlet of the first gas-solid separation device is located in the lower part of the gas-solid separation zone, and the gas outlet of the first gas-solid separation device is located in the upper part of the gas-solid separation zone.

[0036] Optionally, the inlet of the second gas-solid separation device is located in the upper part of the gas-solid separation zone.

[0037] The catalyst outlet of the second gas-solid separation device is located in the lower part of the gas-solid separation zone.

[0038] Optionally, the first gas-solid separation device is an inertial separator.

[0039] Optionally, the second gas-solid separation device is a group or multiple groups of gas-solid cyclone separators, and each group of gas-solid cyclone separators includes a first-stage gas-solid cyclone separator and a second-stage gas-solid cyclone separator.

[0040] Optionally, the high-density fast fluidized bed reactor includes a reactor gas collecting chamber and a product gas delivery pipe;

[0041] The reactor gas collecting chamber is located at the top of the high-density fast fluidized bed reactor;

[0042] The product gas delivery pipe is connected to the top of the reactor gas collecting chamber;

[0043] The gas outlet of the second gas-solid separation device is communicated with the reactor gas collecting chamber.

[0044] The high-density fast fluidized bed reactor of the present application mainly includes a reaction zone, a catalyst residence zone, and a gas-solid separation zone. The catalyst circulation intensity flowing from the catalyst residence zone to the reaction zone is as high as 500-1000 kg / (m 2 ·s), thereby increasing the bed density of the reaction zone, achieving a high bed density under high apparent linear velocity conditions, and overcoming the negative correlation between the raw material feed rate and the bed density of the fluidized bed reaction zone.

[0045] In a second aspect, the present application provides a methanol-to-olefins device, which includes the above-mentioned high-density fast fluidized bed reactor and a fluidized bed regenerator;

[0046] The catalyst extraction pipe passes through the reactor outer shell and is located at the lower part of the catalyst residence zone. The catalyst extraction pipe is communicated with the reactor stripper;

[0047] The inlet of the spent catalyst slide valve is connected to the bottom of the reactor stripper, the outlet of the spent catalyst slide valve is connected to the inlet of the spent catalyst delivery pipe, and the outlet of the spent catalyst delivery pipe is communicated with the fluidized bed regenerator;

[0048] The regenerator stripper is located at the bottom of the fluidized bed regenerator, and a regenerator heat exchanger is provided in the regenerator stripper; the inlet of the regenerated catalyst slide valve is connected to the bottom of the regenerator stripper, the outlet of the regenerated catalyst slide valve is connected to the inlet of the regenerated catalyst delivery pipe, and the outlet of the regenerated catalyst delivery pipe is connected to the lower part of the gas-solid separation zone of the high-density fast fluidized bed reactor (i.e., the catalyst inlet where the regenerated catalyst returns to the reactor).

[0049] Optionally, the fluidized bed regenerator includes a regenerator shell, a regenerator distributor, a third gas-solid separation device, a regenerator gas collecting chamber, and a flue gas delivery pipe;

[0050] The regenerator distributor is located at the bottom of the fluidized bed regenerator;

[0051] The third gas-solid separation device is located in the upper part of the fluidized bed regenerator. The inlet of the third gas-solid separation device is located in the upper part of the fluidized bed regenerator. The gas outlet of the third gas-solid separation device is communicated with the regenerator gas collection chamber. The catalyst outlet of the third gas-solid separation device is located in the lower part of the fluidized bed regenerator. The regenerator gas collection chamber is located at the top of the fluidized bed regenerator. The flue gas conveying pipe is connected to the top of the regenerator gas collection chamber.

[0052] Optionally, the inlet pipe of the regenerator stripper penetrates the regenerator shell and opens above the regenerator distributor.

[0053] Optionally, the third gas-solid separation device adopts one or more groups of gas-solid cyclone separators. Each group of gas-solid cyclone separators includes a first-stage gas-solid cyclone separator and a second-stage gas-solid cyclone separator.

[0054] In a third aspect, the present application provides a method for flexibly regulating the olefin product distribution, and the method is carried out by using the above device.

[0055] Optionally, the method includes the following steps:

[0056] The gasified raw material including methanol and / or dimethyl ether is introduced into the reaction zone, contacts with the catalyst, and reacts to generate a stream I containing product gas and catalyst.

[0057] The stream I passes through the conveying pipe, and the catalyst after gas-solid separation enters the catalyst residence zone, and the product gas after gas-solid separation enters the downstream section.

[0058] A part of the catalyst in the catalyst residence zone enters the reaction zone, and another part of the catalyst is sent to the fluidized bed regenerator for regeneration, and the regenerated catalyst enters the high-density fast fluidized bed reactor.

[0059] Optionally, the stream I enters the first gas-solid separation device through the conveying pipe, and the catalyst after the first gas-solid separation enters the catalyst residence zone.

[0060] Optionally, steam enters the catalyst residence zone from the fluidizing steam distributor. The steam carries a part of the catalyst in the catalyst residence zone into the gas-solid separation zone. The product gas and a part of the catalyst carried by the steam in the gas-solid separation zone enter the second gas-solid separation device. The gas after the second gas-solid separation enters the reactor gas collection chamber, and the separated catalyst returns to the catalyst residence zone.

[0061] Optionally, the product gas and steam after the second gas-solid separation enter the downstream section via the product gas transfer pipe; a part of the catalyst in the catalyst residence zone enters the reaction zone through the catalyst distribution pipe; a part of the catalyst in the catalyst residence zone enters the bottom of the reaction zone through the bottom of the catalyst residence zone; and a part of the catalyst in the catalyst residence zone enters the reactor stripper through the catalyst extraction pipe.

[0062] Optionally, the raw materials include methanol and the crude ethylene separated from the product gas, and the mass content of ethylene in the crude ethylene is greater than 90%, and the remaining components include at least one of methane, ethane, propane, and propylene.

[0063] Optionally, the raw materials include methanol and the crude propylene separated from the product gas, and the mass content of propylene in the crude propylene is greater than 90%, and the remaining components include at least one of ethane, ethylene, propane, butane, and butene.

[0064] In this application, by recycling ethylene, the production of propylene and butene can be increased, and by recycling propylene, the production of butene can be increased, realizing flexible adjustment of the distribution of ethylene, propylene, and butene; the latent content of α-butene in the product can reach up to 57% wt at most.

[0065] Optionally, the catalyst is selected from SAPO molecular sieve catalysts.

[0066] Optionally, the process operating conditions in the reaction zone of the high-density fast fluidized bed reactor include:

[0067] The superficial gas velocity is 1.5 - 7.0 m / s, the temperature is 350 - 500 °C, the pressure is 50 - 500 kPa, and the bed density is 100 - 500 kg / m 3 .

[0068] Optionally, the superficial gas velocity in the reaction zone is selected from any value or the range value between any two of 1.5 m / s, 2 m / s, 2.5 m / s, 3 m / s, 3.5 m / s, 4 m / s, 4.5 m / s, 5 m / s, 5.5 m / s, 6 m / s, 6.5 m / s, 7 m / s.

[0069] Optionally, the temperature in the reaction zone is selected from any value or the range value between any two of 350 °C, 380 °C, 400 °C, 420 °C, 450 °C, 480 °C, 500 °C.

[0070] Optionally, the pressure in the reaction zone is selected from any value or the range value between any two of 50 kPa, 100 kPa, 150 kPa, 200 kPa, 250 kPa, 300 kPa, 350 kPa, 400 kPa, 450 kPa, 500 kPa.

[0071] Optionally, the bed density of the reaction zone is selected from any value of 100 kg / m 3 , 150 kg / m 3 , 200 kg / m 3 , 250 kg / m 3 , 300 kg / m 3 , 350 kg / m 3 , 400 kg / m 3 , 450 kg / m 3 , 500 kg / m 3 or a range value between any two of them.

[0072] Optionally, the process operating conditions of the catalyst residence zone include:

[0073] The superficial gas linear velocity is 0.02 - 0.2 m / s, the temperature is 350 - 500 °C, and the bed density is 500 - 800 kg / m 3 .

[0074] Optionally, the superficial gas linear velocity of the catalyst residence zone is selected from any value of 0.02 m / s, 0.05 m / s, 0.08 m / s, 0.1 m / s, 0.12 m / s, 0.15 m / s, 0.18 m / s, 0.20 m / s or a range value between any two of them.

[0075] Optionally, the temperature of the catalyst residence zone is selected from any value of 350 °C, 380 °C, 400 °C, 420 °C, 450 °C, 480 °C, 500 °C or a range value between any two of them.

[0076] Optionally, the bed density of the catalyst residence zone is 500 kg / m 3 , 550 kg / m 3 , 600 kg / m 3 , 650 kg / m 3 , 700 kg / m 3 , 750 kg / m 3 , 800 kg / m 3 or a range value between any two of them.

[0077] Optionally, the catalyst circulation intensity of the catalyst residence zone flowing to the reaction zone is 500 - 1000 kg / (m 2 ·s).

[0078] Optionally, the catalyst circulation intensity is selected from any value of 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000 or a range value between any two of them, with the unit kg / (m 2 ·s).

[0079] Optionally, the regeneration gas is air or a mixture of air and steam.

[0080] This application provides a specific methanol-to-olefins device, including: a reactor outer shell, a reactor inner shell, a transfer pipe, a raw material distributor, a first gas-solid separation device, a fluidizing steam distributor, a catalyst distribution pipe, a reactor heat exchanger, a second gas-solid separation device, a reactor gas collection chamber, a product gas transfer pipe, a catalyst extraction pipe, a reactor stripper, a spent catalyst slide valve, and a spent catalyst transfer pipe;

[0081] The area enclosed by the reactor inner shell is the reaction zone, and the annular area enclosed by the reactor outer shell and the reactor inner shell is the catalyst residence zone. The bottom of the reaction zone is connected to the bottom of the catalyst residence zone. The area enclosed by the reactor outer shell and the transfer pipe is the gas-solid separation zone. The catalyst residence zone is connected to the gas-solid separation zone and is located below the gas-solid separation zone. The raw material distributor is located at the bottom of the reaction zone. The transfer pipe is located in the central area of the upper and middle parts of the high-density fast fluidized bed reactor. The bottom end of the transfer pipe is connected to the top of the reaction zone, and the outlet of the transfer pipe is connected to the inlet of the first gas-solid separation device. The first gas-solid separation device is located in the gas-solid separation zone. The catalyst outlet of the first gas-solid separation device is located in the lower part of the gas-solid separation zone, and the gas outlet of the first gas-solid separation device is located in the upper part of the gas-solid separation zone. The fluidizing steam distributor is located at the bottom of the catalyst residence zone. The catalyst distribution pipe passes through the reactor inner shell to connect the catalyst residence zone and the reaction zone, and the lower surface of the catalyst distribution pipe is perforated. The reactor heat exchanger is located in the catalyst residence zone. The second gas-solid separation device is located in the gas-solid separation zone. The inlet of the second gas-solid separation device is located in the gas-solid separation zone. The gas outlet of the second gas-solid separation device is connected to the reactor gas collection chamber, and the catalyst outlet of the second gas-solid separation device is located in the lower part of the gas-solid separation zone. The reactor gas collection chamber is located at the top of the high-density fast fluidized bed reactor, and the product gas transfer pipe is connected to the top of the reactor gas collection chamber;

[0082] The catalyst extraction pipe passes through the reactor outer shell and is located in the lower part of the catalyst residence zone. The reactor stripper is connected to the catalyst extraction pipe. The inlet of the spent catalyst slide valve is connected to the bottom of the reactor stripper, the outlet of the spent catalyst slide valve is connected to the inlet of the spent catalyst transfer pipe, and the outlet of the spent catalyst transfer pipe is connected to the fluidized bed regenerator;

[0083] The first gas-solid separation device uses an inertial separator to achieve rapid separation of the product gas and the catalyst. The second gas-solid separation device uses one or more groups of gas-solid cyclone separators, and each group of gas-solid cyclone separators includes a first-stage gas-solid cyclone separator and a second-stage gas-solid cyclone separator;

[0084] The fluidized bed regenerator for regenerating catalyst comprises: a regenerator shell, a regenerator distributor, a third gas-solid separation device, a regenerator gas collecting chamber, a flue gas conveying pipe, a regenerator stripper, a regenerator heat exchanger, a regenerating slide valve and a regenerated catalyst conveying pipe;

[0085] The regenerator distributor is located at the bottom of the fluidized bed regenerator, the third gas-solid separation device is located at the upper part of the fluidized bed regenerator, the inlet of the third gas-solid separation device is located at the upper part of the fluidized bed regenerator, the gas outlet of the third gas-solid separation device is connected to the regenerator gas collecting chamber, the catalyst outlet of the third gas-solid separation device is located at the lower part of the fluidized bed regenerator, the regenerator gas collecting chamber is located at the top of the fluidized bed regenerator, and the flue gas conveying pipe is connected to the top of the regenerator gas collecting chamber;

[0086] The regenerator stripper is located outside the regenerator shell, the inlet pipe of the regenerator stripper penetrates the regenerator shell and opens above the regenerator distributor; the regenerator heat exchanger is located in the regenerator stripper, the inlet of the regenerating slide valve is connected to the bottom of the regenerator stripper, the outlet of the regenerating slide valve is connected to the inlet of the regenerated catalyst conveying pipe, and the outlet of the regenerated catalyst conveying pipe is connected to the lower part of the gas-solid separation zone of the high-density fast fluidized bed reactor;

[0087] The third gas-solid separation device adopts one or more groups of gas-solid cyclone separators, and each group of gas-solid cyclone separators comprises a first-stage gas-solid cyclone separator and a second-stage gas-solid cyclone separator.

[0088] The present application provides a specific method for flexibly regulating the olefin product distribution, comprising:

[0089] a. The catalyst from the regenerated catalyst conveying pipe enters the gas-solid separation zone of the high-density fast fluidized bed reactor, and then enters the catalyst residence zone; the gasified raw material enters the reaction zone from the raw material distributor, contacts with the catalyst to generate product gas containing olefins, the product gas carries the catalyst and enters the first gas-solid separation device through the conveying pipe, after gas-solid separation, the catalyst enters the catalyst residence zone; steam enters the catalyst residence zone from the fluidizing steam distributor, and the steam carries a small amount of catalyst and enters the gas-solid separation zone from the catalyst residence zone; the product gas and steam in the gas-solid separation zone carry the catalyst and enter the second gas-solid separation device, after gas-solid separation, the gas enters the reactor gas collecting chamber, and the catalyst returns to the catalyst residence zone; the product gas and steam enter the downstream section through the product gas conveying pipe; the catalyst in the catalyst residence zone enters the reaction zone through the catalyst distribution pipe; the catalyst in the catalyst residence zone enters the bottom of the reaction zone from the bottom of the catalyst residence zone; the catalyst in the catalyst residence zone enters the reactor stripper through the catalyst extraction pipe, after stripping, the catalyst enters the middle part of the fluidized bed regenerator through the spent catalyst slide valve and the spent catalyst conveying pipe; the heat released by the reaction is taken out by the reactor heat exchanger;

[0090] b. The regeneration gas enters the bottom of the fluidized bed regenerator from the regenerator distributor. In the fluidized bed regenerator, the regeneration gas contacts the catalyst, and part of the carbon deposit in the catalyst is burned off. The flue gas formed by combustion carries the catalyst into the third gas-solid separation device. After gas-solid separation, the flue gas enters the regenerator gas collection chamber and then enters the downstream flue gas treatment system through the flue gas transfer pipe. The catalyst returns to the bottom of the fluidized bed regenerator. The catalyst in the fluidized bed regenerator enters the regenerator stripper. After stripping and heat extraction, it then enters the high-density fast fluidized bed reactor through the regeneration slide valve and the regenerant transfer pipe;

[0091] The raw material is one of methanol or dimethyl ether or a mixture of methanol and dimethyl ether; the raw material is methanol and crude ethylene separated from the product gas, and the mass content of ethylene in the crude ethylene is greater than 90%, and other components include methane, ethane, propane, and propylene; the raw material is methanol and crude propylene separated from the product gas, and the mass content of propylene in the crude propylene is greater than 90%, and other components include ethane, ethylene, propane, butane, and butene; the catalyst is a SAPO molecular sieve catalyst;

[0092] The process operating conditions in the reaction zone of the high-density fast fluidized bed reactor are: the superficial gas linear velocity is 1.5 - 7.0 m / s, the temperature is 350 - 500 °C, the pressure is 50 - 500 kPa, and the bed density is 100 - 500 kg / m 3 ;

[0093] The process operating conditions in the catalyst residence zone are: the superficial gas linear velocity is 0.02 - 0.2 m / s, the temperature is 350 - 500 °C, and the bed density is 500 - 800 kg / m 3 ; The catalyst circulation intensity of the catalyst flowing from the catalyst residence zone to the reaction zone is 500 - 1000 kg / (m 2 ·s);

[0094] The regeneration gas is air or a mixture of air and steam;

[0095] The process operating conditions of the fluidized bed regenerator are: the superficial gas linear velocity is 0.5 - 2.0 m / s, the regeneration temperature is 600 - 750 °C, the regeneration pressure is 100 - 500 kPa, and the bed density is 150 - 700 kg / m 3 .

[0096] In the method described in this application, the composition of the product does not contain water generated from methanol or dimethyl ether.

[0097] The C5+ hydrocarbons described in this application refer to hydrocarbons with the number of carbon atoms in the molecule greater than or equal to 5.

[0098] In the method described in this application, the potential content of α-butene in the butene product is ≥ 95% wt; the highest potential content of α-butene in the product can reach 57% wt.

[0099] In the method described in this application, the potential content of α-butene in the butene product refers to the content of 1-butene and 2-butene in the butene product, and the potential content of α-butene in the product refers to the content of 1-butene and 2-butene in the product.

[0100] Compared with the prior art, this application has the following beneficial effects:

[0101] (1) This application discloses a high-density fast fluidized bed reactor, which mainly includes a reaction zone, a catalyst residence zone, and a gas-solid separation zone. The catalyst circulation intensity flowing from the catalyst residence zone to the reaction zone is as high as 500 - 1000 kg / (m 2 ·s), thereby increasing the bed density of the reaction zone, achieving a high bed density under high apparent linear velocity conditions, and overcoming the negative correlation between the raw material feed rate and the bed density of the fluidized bed reaction zone.

[0102] (2) The first gas-solid separation device in the high-density fast fluidized bed reactor in this application uses an inertial separator to achieve rapid separation of product gas and catalyst, greatly shortening the gas-solid contact time and reducing alkanes and C5+ hydrocarbons in the product.

[0103] (3) The method for producing olefins from methanol in this application can increase the production of propylene and butene by recycling ethylene, and can increase the production of butene by recycling propylene, realizing flexible adjustment of the distribution of ethylene, propylene, and butene.

[0104] (4) In the method for producing olefins from methanol in this application, the highest potential content of α-butene in the product can reach 57% wt. BRIEF DESCRIPTION OF THE DRAWINGS

[0105] Figure 1 It is a schematic diagram of the device for an embodiment of this application.

[0106] Figure 1 The descriptions of the reference numerals in the drawings are as follows:

[0107] 1 - High-density fast fluidized bed reactor;

[0108] 1-1 Reactor outer shell, 1-2 Reactor inner shell, 1-3 Delivery pipe, 1-4 Raw material distributor, 1-5 First gas-solid separation device, 1-6 Fluidizing steam distributor, 1-7 Catalyst distribution pipe, 1-8 Reactor heat exchanger, 1-9 Second gas-solid separation device, 1-10 Reactor gas collection chamber, 1-11 Product gas delivery pipe, 1-12 Catalyst extraction pipe, 1-13 Reactor stripper, 1-14 Spent catalyst slide valve, 1-15 Spent catalyst delivery pipe;

[0109] 2 - Fluidized bed regenerator;

[0110] 2 - 1 Regenerator shell, 2 - 2 Regenerator distributor, 2 - 3 Third gas - solid separation equipment, 2 - 4 Regenerator gas - collecting chamber, 2 - 5 Flue gas transfer pipe, 2 - 6 Regenerator stripper, 2 - 7 Regenerator heat - extracting device, 2 - 8 Regeneration slide valve, 2 - 9 Regenerated catalyst transfer pipe. Detailed implementation manners

[0111] The present application will be described in detail below in conjunction with embodiments, but the present application is not limited to these embodiments.

[0112] Unless otherwise specified, the raw materials and catalysts in the embodiments of the present application are all purchased through commercial channels.

[0113] In a specific implementation manner, the present application provides a device of an implementation manner, and its structural schematic diagram is as Figure 1 shown, and this device includes a high - density fast fluidized bed reactor (1) and a fluidized bed regenerator (2).

[0114] a. The high-density fast fluidized bed reactor (1) includes: a reactor outer shell (1-1), a reactor inner shell (1-2), a conveying pipe (1-3), a raw material distributor (1-4), a first gas-solid separation device (1-5), a fluidizing steam distributor (1-6), a catalyst distribution pipe (1-7), a reactor heat exchanger (1-8), a second gas-solid separation device (1-9), a reactor gas collecting chamber (1-10), a product gas conveying pipe (1-11), a catalyst extraction pipe (1-12), a reactor stripper (1-13), a spent catalyst slide valve (1-14) and a spent catalyst conveying pipe (1-15); the area enclosed by the reactor inner shell (1-2) is the reaction zone (A), the annular area enclosed by the reactor outer shell (1-1) and the reactor inner shell (1-2) is the catalyst residence zone (B), the bottom of the reaction zone (A) is communicated with the bottom of the catalyst residence zone (B), the area enclosed by the reactor outer shell (1-1) and the conveying pipe (1-3) is the gas-solid separation zone (C), the catalyst residence zone (B) is communicated with the gas-solid separation zone (C) and is located below the gas-solid separation zone (C); the raw material distributor (1-4) is located at the bottom of the reaction zone (A), the conveying pipe (1-3) is located in the central area of the middle and upper parts of the high-density fast fluidized bed reactor, the bottom end of the conveying pipe (1-3) is connected to the top end of the reaction zone (A), and the outlet of the conveying pipe (1-3) is connected to the inlet of the first gas-solid separation device (1-5); the first gas-solid separation device (1-5) is located in the gas-solid separation zone (C), the catalyst outlet of the first gas-solid separation device (1-5) is located in the lower part of the gas-solid separation zone (C), and the gas outlet of the first gas-solid separation device (1-5) is located in the upper part of the gas-solid separation zone (C); the fluidizing steam distributor (1-6) is located at the bottom of the catalyst residence zone (B); the catalyst distribution pipe (1-7) passes through the reactor inner shell (1-2) to communicate the catalyst residence zone (B) and the reaction zone (A), and the lower surface of the catalyst distribution pipe (1-7) is provided with openings; the reactor heat exchanger (1-8) is located in the catalyst residence zone (B); the second gas-solid separation device (1-9) is located in the gas-solid separation zone (C), the inlet of the second gas-solid separation device (1-9) is located in the gas-solid separation zone (C), the gas outlet of the second gas-solid separation device (1-9) is connected to the reactor gas collecting chamber (1-10), and the catalyst outlet of the second gas-solid separation device (1-9) is located in the lower part of the gas-solid separation zone (C); the reactor gas collecting chamber (1-10) is located at the top of the high-density fast fluidized bed reactor, and the product gas conveying pipe (1-11) is connected to the top of the reactor gas collecting chamber (1-10); the catalyst extraction pipe (1-12) passes through the reactor outer shell (1-1) and is located in the lower part of the catalyst residence zone (B);The reactor stripper (1-13) is connected to the catalyst extraction pipe (1-12). The inlet of the spent catalyst slide valve (1-14) is connected to the bottom of the reactor stripper (1-13). The outlet of the spent catalyst slide valve (1-14) is connected to the inlet of the spent catalyst transfer pipe (1-15). The outlet of the spent catalyst transfer pipe (1-15) is connected to the fluidized bed regenerator (2).;

[0115] b. The fluidized bed regenerator (2) includes: a regenerator shell (2-1), a regenerator distributor (2-2), a third gas-solid separation device (2-3), a regenerator gas collection chamber (2-4), a flue gas transfer pipe (2-5), a regenerator stripper (2-6), a regenerator heat exchanger (2-7), a regenerated catalyst slide valve (2-8) and a regenerated catalyst transfer pipe (2-9); The regenerator distributor (2-2) is located at the bottom of the fluidized bed regenerator (2). The third gas-solid separation device (2-3) is located at the upper part of the fluidized bed regenerator (2). The inlet of the third gas-solid separation device (2-3) is located at the upper part of the fluidized bed regenerator (2). The gas outlet of the third gas-solid separation device (2-3) is connected to the regenerator gas collection chamber (2-4). The catalyst outlet of the third gas-solid separation device (2-3) is located at the lower part of the fluidized bed regenerator (2). The regenerator gas collection chamber (2-4) is located at the top of the fluidized bed regenerator (2). The flue gas transfer pipe (2-5) is connected to the top of the regenerator gas collection chamber (2-4); The regenerator stripper (2-6) is located outside the regenerator shell (2-1). The inlet pipe of the regenerator stripper (2-6) penetrates the regenerator shell (2-1) and opens above the regenerator distributor (2-2). The regenerator heat exchanger (2-7) is located in the regenerator stripper (2-6). The inlet of the regenerated catalyst slide valve (2-8) is connected to the bottom of the regenerator stripper (2-6). The outlet of the regenerated catalyst slide valve (2-8) is connected to the inlet of the regenerated catalyst transfer pipe (2-9). The outlet of the regenerated catalyst transfer pipe (2-9) is connected to the lower part of the gas-solid separation zone (C) of the high-density fast fluidized bed reactor (1).

[0116] As a preference of the above embodiment, the first gas-solid separation device (1-5) adopts an inertial separator to achieve rapid separation of the product gas and the catalyst.

[0117] As a preference of the above embodiment, the second gas-solid separation device (1-9) adopts one or more groups of gas-solid cyclone separators. Each group of gas-solid cyclone separators includes a first-stage gas-solid cyclone separator and a second-stage gas-solid cyclone separator.

[0118] As a preference of the above embodiment, the third gas-solid separation device (2-3) adopts one or more groups of gas-solid cyclone separators. Each group of gas-solid cyclone separators includes a first-stage gas-solid cyclone separator and a second-stage gas-solid cyclone separator.

[0119] In a specific embodiment, the present application provides a method for flexibly regulating the olefin product distribution, comprising the following steps:

[0120] a. The catalyst from the regenerant delivery pipe (2-9) enters the gas-solid separation zone (C) of the high-density fast fluidized bed reactor (1), and then enters the catalyst residence zone (B); the gasified raw material enters the reaction zone (A) from the raw material distributor (1-4), contacts the catalyst, generates product gas containing olefins, and the product gas carries the catalyst through the delivery pipe (1-3) into the first gas-solid separation device (1-5). After gas-solid separation, the catalyst enters the catalyst residence zone (B); steam enters the catalyst residence zone (B) from the fluidizing steam distributor (1-6), and the steam carries a small amount of catalyst from the catalyst residence zone (B) into the gas-solid separation zone (C); the product gas and steam carrying the catalyst in the gas-solid separation zone (C) enter the second gas-solid separation device (1-9). After gas-solid separation, the gas enters the reactor gas collection chamber (1-10), and the catalyst returns to the catalyst residence zone (B); the product gas and steam enter the downstream section via the product gas delivery pipe (1-11); the catalyst in the catalyst residence zone (B) enters the reaction zone (A) through the catalyst distribution pipe (1-7); the catalyst in the catalyst residence zone (B) enters the bottom of the reaction zone (A) from the bottom of the catalyst residence zone (B); the catalyst in the catalyst residence zone (B) enters the reactor stripper (1-13) through the catalyst extraction pipe (1-12). After stripping, the catalyst then enters the middle part of the fluidized bed regenerator (2) via the spent catalyst slide valve (1-14) and the spent catalyst delivery pipe (1-15); the heat released by the reaction is taken out by the reactor heat exchanger (1-8);

[0121] b. The regeneration gas enters the bottom of the fluidized bed regenerator (2) from the regenerator distributor (2-2). In the fluidized bed regenerator (2), the regeneration gas contacts the catalyst, and part of the coke deposited on the catalyst is burned and removed. The flue gas formed by the combustion carries the catalyst into the third gas-solid separation device (2-3). After gas-solid separation, the flue gas enters the regenerator gas collection chamber (2-4), and then enters the downstream flue gas treatment system via the flue gas delivery pipe (2-5). The catalyst returns to the bottom of the fluidized bed regenerator (2). The catalyst in the fluidized bed regenerator (2) enters the regenerator stripper (2-6). After stripping and heat extraction, it then enters the high-density fast fluidized bed reactor (1) via the regenerated catalyst slide valve (2-8) and the regenerated catalyst delivery pipe (2-9).

[0122] Example 1

[0123] This Example 1 uses Figure 1 the device shown.

[0124] In this Example 1, the raw material is methanol; the catalyst is a SAPO molecular sieve catalyst.

[0125] The process operating conditions of the reaction zone (A) of the high-density fast fluidized bed reactor (1) are as follows: the superficial gas linear velocity is 1.5 m / s, the temperature is 450 °C, the pressure is 500 kPa, and the bed density is 500 kg / m 3 .

[0126] The process operating conditions of the catalyst residence zone (B) are as follows: the superficial gas linear velocity is 0.12 m / s, the temperature is 450 °C, and the bed density is 630 kg / m 3 ; the catalyst circulation intensity flowing from the catalyst residence zone (B) to the reaction zone (A) is 500 kg / (m 2 ·s).

[0127] The regeneration gas is air. The process operating conditions of the fluidized bed regenerator (2) are as follows: the superficial gas linear velocity is 0.5 m / s, the regeneration temperature is 600 °C, the regeneration pressure is 500 kPa, and the bed density is 700 kg / m 3 .

[0128] In Example 1 of the present invention, the composition of the product is 28 wt% ethylene, 42 wt% propylene, 22 wt% butene, and 8 wt% of other components. The other components are methane, ethane, propane, butane, C5+ hydrocarbons, hydrogen, CO, CO2, coke, etc. The sum of the contents of ethylene, propylene, and butene in the product is 92 wt%, and the latent content of α-butene in the product is 21 wt%.

[0129] Example 2

[0130] In this Example 2, Figure 1 the device shown is used.

[0131] In this Example 2, the raw material is dimethyl ether; the catalyst is a SAPO molecular sieve catalyst.

[0132] The process operating conditions of the reaction zone (A) of the high-density fast fluidized bed reactor (1) are as follows: the superficial gas linear velocity is 3.0 m / s, the temperature is 350 °C, the pressure is 270 kPa, and the bed density is 290 kg / m 3 .

[0133] The process operating conditions of the catalyst residence zone (B) are as follows: the superficial gas linear velocity is 0.2 m / s, the temperature is 350 °C, and the bed density is 500 kg / m 3 . The catalyst circulation intensity flowing from the catalyst residence zone (B) to the reaction zone (A) is 760 kg / (m 2 ·s).

[0134] The regenerated gas is a mixture of air and water vapor. The process operating conditions of the fluidized bed regenerator (2) are as follows: the apparent gas linear velocity is 2.0 m / s, the regeneration temperature is 650 °C, the regeneration pressure is 270 kPa, and the bed density is 150 kg / m 3 .

[0135] In this Example 2, the composition of the product is 21% wt ethylene, 46% wt propylene, 26% wt butene, and 7% wt of other components. The other components are methane, ethane, propane, butane, C5+ hydrocarbons, hydrogen, CO, CO2, and coke, etc. The sum of the contents of ethylene, propylene, and butene in the product is 93% wt, and the latent content of α-butene in the product is 25% wt.

[0136] Example 3

[0137] This Example 3 uses Figure 1 the device shown.

[0138] In this Example 3, the raw materials are methanol and crude ethylene separated from the product gas. The mass content of ethylene in the crude ethylene is greater than 90%, and the other components include methane, ethane, propane, and propylene.

[0139] The catalyst is a SAPO molecular sieve catalyst.

[0140] The process operating conditions of the reaction zone (A) of the high-density fast fluidized bed reactor (1) are as follows: the apparent gas linear velocity is 5.0 m / s, the temperature is 400 °C, the pressure is 100 kPa, and the bed density is 180 kg / m 3 .

[0141] The process operating conditions of the catalyst residence zone (B) are as follows: the apparent gas linear velocity is 0.09 m / s, the temperature is 400 °C, and the bed density is 730 kg / m 3 . The catalyst circulation intensity flowing from the catalyst residence zone (B) to the reaction zone (A) is 1000 kg / (m 2 ·s).

[0142] The regenerated gas is air. The process operating conditions of the fluidized bed regenerator (2) are as follows: the apparent gas linear velocity is 1.4 m / s, the regeneration temperature is 690 °C, the regeneration pressure is 100 kPa, and the bed density is 330 kg / m 3 .

[0143] In this Example 3, the composition of the product is 5% wt ethylene, 50% wt propylene, 36% wt butene, and 9% wt of other components. The other components are methane, ethane, propane, butane, C5+ hydrocarbons, hydrogen, CO, CO2, and coke, etc. The sum of the contents of ethylene, propylene, and butene in the product is 91% wt, and the latent content of α-butene in the product is 34% wt.

[0144] Example 4

[0145] In this Example 4, the following device is adopted Figure 1 as shown.

[0146] In this Example 4, the raw materials are methanol and the crude propylene separated from the product gas. The mass content of propylene in the crude propylene is greater than 90%, and the other components include ethane, ethylene, propane, butane, and butene.

[0147] The catalyst is a SAPO molecular sieve catalyst.

[0148] The process operating conditions in the reaction zone (A) of the high-density fast fluidized bed reactor (1) are as follows: the superficial gas velocity is 7.0 m / s, the temperature is 500 °C, the pressure is 50 kPa, and the bed density is 100 kg / m 3 .

[0149] The process operating conditions in the catalyst residence zone (B) are as follows: the superficial gas velocity is 0.02 m / s, the temperature is 500 °C, and the bed density is 800 kg / m 3 . The catalyst circulation intensity flowing from the catalyst residence zone (B) to the reaction zone (A) is 850 kg / (m 2 ·s).

[0150] The regeneration gas is air. The process operating conditions of the fluidized bed regenerator (2) are as follows: the superficial gas velocity is 0.9 m / s, the regeneration temperature is 750 °C, the regeneration pressure is 50 kPa, and the bed density is 480 kg / m 3 .

[0151] In this Example 4, the composition of the product is 22% wt ethylene, 8% wt propylene, 60% wt butene, and 10% wt of other components. The other components are methane, ethane, propane, butane, C5+ hydrocarbons, hydrogen, CO, CO2, and coke, etc. The sum of the contents of ethylene, propylene, and butene in the product is 90% wt, and the latent content of α-butene in the product is 57% wt.

[0152] The above are only several embodiments of the present application, and do not impose any form of limitation on the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any person skilled in the art, without departing from the scope of the technical solution of the present application, making some changes or modifications using the above-disclosed technical content is equivalent to equivalent implementation cases and all fall within the scope of the technical solution.

Claims

1. A high-density fast fluidized bed reactor, characterized in that, The high-density fast fluidized bed reactor includes a reactor outer shell, a reactor inner shell, a delivery pipe, and a reactor heat extractor; The reactor outer shell is provided with at least a raw material inlet, a catalyst inlet, a gas-phase product outlet, and a catalyst outlet; The reactor outer shell encloses an internal area; The reactor inner shell is located in the lower part of the internal area, and the area enclosed by the reactor inner shell is the reaction zone; The delivery pipe is located in the upper-middle part of the internal area, and the bottom of the delivery pipe communicates with the reaction zone; The area enclosed by the reactor outer shell and the delivery pipe is the gas-solid separation zone; The delivery pipe is provided with an outlet, and the delivery pipe communicates with the gas-solid separation zone; The annular area enclosed by the reactor outer shell and the reactor inner shell is the catalyst residence zone; The bottom of the reaction zone communicates with the bottom of the catalyst residence zone; The catalyst residence zone communicates with the gas-solid separation zone and is located below the gas-solid separation zone; The reactor heat extractor is located in the catalyst residence zone.

2. The high-density fast fluidized bed reactor according to claim 1, characterized in that, The high-density fast fluidized bed reactor includes a catalyst distribution pipe, a fluidizing steam distributor, and a raw material distributor; The catalyst distribution pipe passes through the reactor inner shell to communicate the catalyst residence zone and the reaction zone; The fluidizing steam distributor is arranged at the bottom of the catalyst residence zone; The raw material distributor is arranged at the bottom of the reaction zone; Preferably, through holes are formed on the lower surface of the catalyst distribution pipe.

3. The high-density fast fluidized bed reactor according to claim 1, characterized in that, The high-density fast fluidized bed reactor includes a first gas-solid separation device and a second gas-solid separation device; The first gas-solid separation device and the second gas-solid separation device are located in the gas-solid separation zone; The inlet of the first gas-solid separation device communicates with the outlet of the delivery pipe; The catalyst outlet of the first gas-solid separation device is located in the lower part of the gas-solid separation zone, and the gas outlet of the first gas-solid separation device is located in the upper part of the gas-solid separation zone; Preferably, the inlet of the second gas-solid separation device is located in the upper part of the gas-solid separation zone; The catalyst outlet of the second gas-solid separation device is located in the lower part of the gas-solid separation zone; Preferably, the first gas-solid separation device is an inertial separator; Preferably, the second gas-solid separation device is one or more groups of gas-solid cyclone separators, and each group of gas-solid cyclone separators includes a first-stage gas-solid cyclone separator and a second-stage gas-solid cyclone separator; Preferably, the high-density fast fluidized bed reactor includes a reactor gas collecting chamber and a product gas delivery pipe; The reactor gas collecting chamber is located at the top of the high-density fast fluidized bed reactor; The product gas delivery pipe is connected to the top of the reactor gas collecting chamber; The gas outlet of the second gas-solid separation device communicates with the reactor gas collecting chamber.

4. A methanol-to-olefins device, characterized in that, The device includes the high-density fast fluidized bed reactor according to any one of claims 1 to 3 and a fluidized bed regenerator; The catalyst extraction pipe passes through the reactor outer shell and is located in the lower part of the catalyst residence zone, and the catalyst extraction pipe communicates with the reactor stripper; The inlet of the spent catalyst slide valve is connected to the bottom of the reactor stripper, the outlet of the spent catalyst slide valve is connected to the inlet of the spent catalyst transfer pipe, and the outlet of the spent catalyst transfer pipe communicates with the fluidized bed regenerator; The regenerator stripper is located at the bottom of the fluidized bed regenerator, and a regenerator heat exchanger is provided in the regenerator stripper; the inlet of the regenerated catalyst slide valve is connected to the bottom of the regenerator stripper, the outlet of the regenerated catalyst slide valve is connected to the inlet of the regenerated catalyst transfer pipe, and the outlet of the regenerated catalyst transfer pipe is connected to the lower part of the gas-solid separation zone of the high-density fast fluidized bed reactor.

5. The methanol-to-olefins device according to claim 4, characterized in that, The fluidized bed regenerator includes a regenerator shell, a regenerator distributor, a third gas-solid separation device, a regenerator gas collection chamber, and a flue gas transfer pipe; The regenerator distributor is located at the bottom of the fluidized bed regenerator; The third gas-solid separation device is located in the upper part of the fluidized bed regenerator. The inlet of the third gas-solid separation device is located in the upper part of the fluidized bed regenerator. The gas outlet of the third gas-solid separation device communicates with the regenerator gas collection chamber. The catalyst outlet of the third gas-solid separation device is located in the lower part of the fluidized bed regenerator. The regenerator gas collection chamber is located at the top of the fluidized bed regenerator. The flue gas transfer pipe is connected to the top of the regenerator gas collection chamber; Preferably, the inlet pipe of the regenerator stripper penetrates the regenerator shell and opens above the regenerator distributor; Preferably, the third gas-solid separation device adopts one or more groups of gas-solid cyclone separators, and each group of gas-solid cyclone separators includes a first-stage gas-solid cyclone separator and a second-stage gas-solid cyclone separator.

6. A method for flexibly regulating the olefin product distribution, characterized in that, It is carried out using the device according to claim 4 or 5.

7. The method for flexibly regulating the olefin product distribution according to claim 6, characterized in that, It includes the following steps: Inject the gasified raw material including methanol and / or dimethyl ether into the reaction zone, contact with the catalyst, react, and generate a stream I containing product gas and catalyst; The stream I passes through the transfer pipe, and the catalyst after gas-solid separation enters the catalyst residence zone, and the product gas after gas-solid separation enters the downstream section; Part of the catalyst in the catalyst residence zone enters the reaction zone, and another part of the catalyst is sent to the fluidized bed regenerator for regeneration. The regenerated catalyst enters the high-density fast fluidized bed reactor; Preferably, the stream I enters the first gas-solid separation device through the transfer pipe, and the catalyst after the first gas-solid separation enters the catalyst residence zone; Preferably, steam enters the catalyst residence zone from the fluidizing steam distributor. The steam carries a part of the catalyst in the catalyst residence zone into the gas-solid separation zone; the product gas and a part of the catalyst carried by the steam in the gas-solid separation zone enter the second gas-solid separation device. The gas after the second gas-solid separation enters the reactor gas collection chamber, and the separated catalyst returns to the catalyst residence zone; Preferably, the product gas and steam after the second gas-solid separation enter the downstream section through the product gas transfer pipe; part of the catalyst in the catalyst residence zone enters the reaction zone through the catalyst distribution pipe; Part of the catalyst in the catalyst residence zone enters the bottom of the reaction zone through the bottom of the catalyst residence zone; part of the catalyst in the catalyst residence zone enters the reactor stripper through the catalyst extraction pipe.

8. The method for flexibly regulating the olefin product distribution according to claim 6, characterized in that, The raw materials include methanol and crude ethylene separated from the product gas. The mass content of ethylene in the crude ethylene is greater than 90%, and the remaining components include at least one of methane, ethane, propane, and propylene. Preferably, the raw materials include methanol and crude propylene separated from the product gas. The mass content of propylene in the crude propylene is greater than 90%, and the remaining components include at least one of ethane, ethylene, propane, butane, and butene.

9. The method for flexibly regulating the olefin product distribution according to claim 6, characterized in that, The process operating conditions in the reaction zone of the high-density fast fluidized bed reactor include: The superficial gas linear velocity is 1.5 to 7.0 m / s, the temperature is 350 to 500 °C, the pressure is 50 to 500 kPa, and the bed density is 100 to 500 kg / m 3 ; Preferably, the process operating conditions in the catalyst residence zone include: The superficial gas linear velocity is 0.02 - 0.2 m / s, the temperature is 350 - 500 °C, and the bed density is 500 - 800 kg / m 3 ; Preferably, the catalyst circulation intensity of the catalyst flowing from the catalyst residence zone to the reaction zone is 500 to 1000 kg / (m 2 ·s).

10. The method for flexibly regulating the olefin product distribution according to claim 6, characterized in that, The regeneration gas is air or a mixture of air and steam; Preferably, the catalyst is selected from SAPO molecular sieve catalysts.

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