FLUIDIZED BED REACTOR, DEVICE, AND USE THEREOF

Abstract

A fluidized bed reactor includes a main shell and a coke control zone shell; the main shell includes an upper shell and a lower shell; the upper shell encloses a gas-solid separation zone, and the lower shell encloses a reaction zone; the reaction zone axially communicates with the gas-solid separation zone; the coke control zone shell is circumferentially arranged on an outer wall of the main shell; the coke control zone shell and the main shell enclose an annular cavity, and the annular cavity is a coke control zone; n baffles are radially arranged in the coke control zone, and the n baffles divide the coke control zone into n coke control zone subzones, where n is an integer; the coke control zone subzones are provided with a coke control raw material inlet; and a catalyst circulation hole is formed in each of n-1 of the baffles.

Claims

1. A fluidized bed reactor, wherein the fluidized bed reactor comprises a main shell and a coke control zone shell; the main shell comprises an upper shell and a lower shell; the upper shell encloses a first gas-solid separation zone, and the lower shell encloses a reaction zone; the reaction zone axially communicates with the first gas-solid separation zone; the coke control zone shell is circumferentially arranged on an outer wall of the main shell; the coke control zone shell and the main shell enclose an annular cavity, and the annular cavity is a coke control zone; n baffles are radially arranged in the coke control zone, and the n baffles divide the coke control zone into n coke control zone subzones, where n is an integer; each of the n coke control zone subzones is provided with a coke control raw material inlet; and a catalyst circulation hole is formed in each of n−1 of the n baffles, such that a catalyst and a coke control raw material entering the coke control zone flow in an annular direction.

2. The fluidized bed reactor according to claim 1, wherein in the coke control zone, the n baffles comprise a 1.sup.st baffle, and a 2.sup.nd baffle to an n.sup.th baffle; no catalyst circulation hole is formed in the 1.sup.st baffle; the catalyst circulation hole is formed in each of the 2.sup.st baffle to the n.sup.th baffle; a coke control zone catalyst inlet is formed in a 1.sup.st coke control zone subzone formed through division by the 1.sup.st baffle and the 2.sup.nd baffle; a coke controlled catalyst delivery pipe is arranged in an n.sup.th coke control zone subzone formed through division by the 1.sup.st baffle and the n.sup.th baffle, and an outlet of the coke controlled catalyst delivery pipe is formed in the reaction zone; the coke control raw material inlet is formed at bottoms of the coke control zone subzones, and the coke control raw material inlet is a coke control zone distributor; and a coke control zone gas delivery pipe is arranged at tops of the coke control zone subzones, and an outlet of the coke control zone gas delivery pipe is formed in the first gas-solid separation zone.

3. The fluidized bed reactor according to claim 1, wherein n has a value range of 2≤n≤10; a reaction zone distributor is arranged at a bottom of the reaction zone, and the reaction zone distributor is configured to feed a reaction raw material; and the reaction zone is provided with a fluidized bed reactor cooler, and the bottom of the reaction zone is provided with a first stripper; an inlet of the first stripper is formed inside the lower shell; an outlet of the first stripper is formed outside the lower shell; an open end of the inlet of the first stripper is located above an outlet end of the coke controlled catalyst delivery pipe; and the outlet end of the coke controlled catalyst delivery pipe is located above the reaction zone distributor.

4. (canceled)

5. (canceled)

6. The fluidized bed reactor according to claim 1, wherein the first gas-solid separation zone is provided with a first gas-solid separation unit and a second gas-solid separation unit; a catalyst outlet pipe of the first gas-solid separation unit penetrates through a top of the coke control zone and is inserted in a 1.sup.st coke control zone subzone; a gas outlet of the first gas-solid separation unit is formed in the first gas-solid separation zone; an inlet of the second gas-solid separation unit is formed in the first gas-solid separation zone; and a catalyst outlet end of the second gas-solid separation unit is located in the reaction zone; wherein a first gas collection chamber is arranged in an upper part of the first gas-solid separation zone; a gas outlet of the second gas-solid separation unit communicates with the first gas collection chamber; and the first gas collection chamber further communicates with a product gas delivery pipe.

7. (canceled)

8. A device for preparing low-carbon olefins from an oxygen-containing compound, wherein the device comprises a fluidized bed regenerator and the fluidized bed reactor according to claim 1.

9. The device according to claim 8, wherein the fluidized bed regenerator comprises a regenerator shell; the regenerator shell comprises an upper regenerator shell and a lower regenerator shell; the upper regenerator shell encloses a second gas-solid separation zone, and the lower regenerator shell encloses a regeneration zone; a spent catalyst inlet is formed in the regenerator shell; and the spent catalyst inlet communicates with a first stripper outlet pipe through a spent catalyst delivery pipe.

10. The device according to claim 9, wherein a regeneration zone distributor is arranged at a bottom of the regeneration zone; and the regeneration zone distributor is configured to feed a regeneration gas; wherein a second stripper is arranged at the bottom of the regeneration zone; an inlet of the second stripper is formed inside the regenerator shell; an outlet of the second stripper is formed outside the regenerator shell; the second stripper communicates with a first gas-solid separation unit through a regenerated catalyst delivery pipe; and an open end of the inlet of the second stripper is located above the regeneration zone distributor.

11. (canceled)

12. The device according to claim 9, wherein a third gas-solid separation unit and a second gas collection chamber are arranged in the regenerator shell; the second gas collection chamber is located at an inner top of the regenerator shell; a gas outlet of the third gas-solid separation unit communicates with the second gas collection chamber; the second gas collection chamber communicates with a flue gas delivery pipe; and a catalyst outlet end of the third gas-solid separation unit is located above an open end of a second stripper inlet pipe.

13-28. (canceled)

29. A method for preparing low-carbon olefins, wherein the method for preparing low-carbon olefins comprises preparing low-carbon olefins using the device according to claim 8; the method for preparing low-carbon olefins comprises preparing low-carbon olefins from an oxygen-containing compound, wherein an on-line modification of a dimethyl ether/methanol to olefins (DMTO) catalyst through a coke control reaction is performed using the fluidized bed reactor; wherein the method comprises the following step: feeding a catalyst and a coke control raw material into the coke control zone, wherein the catalyst reacts with the coke control raw material while flowing in an annular direction along the coke control zone subzones to generate a product comprising a coke controlled catalyst, and the coke controlled catalyst is a modified DMTO catalyst; the method for preparing the low-carbon olefins further comprises the following steps: allowing a spent catalyst in the reaction zone of the fluidized bed reactor to enter the fluidized bed regenerator and undergo a regeneration treatment to generate a regenerated catalyst, and allowing the regenerated catalyst to enter the coke control zone of the fluidized bed reactor and to contact and react with the coke control raw material.

30. The method according to claim 29, wherein the method comprises: allowing the spent catalyst in the reaction zone to enter the fluidized bed regenerator through a first stripper and a spent catalyst delivery pipe, and to contact and react with a regeneration gas to obtain a first stream with a flue gas and the regenerated catalyst; allowing the first stream to enter a third gas-solid separation unit to separate the flue gas and the regenerated catalyst; and allowing the separated regenerated catalyst to enter the coke control zone of the fluidized bed reactor through a second stripper, a regenerated catalyst delivery pipe, and a first gas-solid separation unit, and to contact and react with the coke control raw material.

31. The method according to claim 30, wherein a coke content in the regenerated catalyst is less than or equal to 3 wt %; the regeneration gas is at least one selected from the group consisting of oxygen, nitrogen, water vapor, and air; the regeneration gas comprises 0 wt % to 100 wt % of air, 0 wt % to 50 wt % of oxygen, 0 wt % to 50 wt % of nitrogen, and 0 wt % to 50 wt % of water vapor; and contents of the air, the oxygen, the nitrogen, and the water vapor are not simultaneously zero.

32. (canceled)

33. (canceled)

34. The method according to claim 29, wherein process conditions of the regeneration zone are as follows: apparent gas linear velocity: 0.5 m/s to 2.0 m/s; regeneration temperature: 600° C. to 750° C.; regeneration pressure: 100 kPa to 500 kPa; and bed density: 150 kg/m.sup.3 to 700 kg/m.sup.3.

35. The method according to claim 29, wherein the catalyst flows in the annular direction along the catalyst circulation hole on each of n−1 of the n baffles; and the coke control raw material enters the n coke control zone subzones from the coke control zone distributor to react with the catalyst; wherein the coke controlled catalyst prepared enters the reaction zone through the coke controlled catalyst delivery pipe, and then contacts and reacts with a raw material comprising the oxygen-containing compound fed through a reaction zone distributor to generate a second stream with low-carbon olefins and a spent catalyst; and the product further comprises a coke control product gas, and the coke control product gas enters the first gas-solid separation zone through a coke control zone gas delivery pipe; wherein the second stream is mixed with the coke control product gas entering the first gas-solid separation zone to produce a third stream; the third stream enters a second gas-solid separation unit to undergo gas-solid separation to obtain a gas-phase stream and a solid-phase stream; the gas-phase stream is a low-carbon olefin-containing product gas; and the solid-phase stream comprises the spent catalyst; wherein the gas-phase stream enters a first gas collection chamber, and then enters a downstream working section through a product gas delivery pipe; the solid-phase stream is returned to the reaction zone of the fluidized bed reactor; and the catalyst in the reaction zone enters a first stripper through an open end of a first stripper inlet pipe to undergo stripping, and then enters a downstream zone.

36. The method according to claim 29, wherein the coke control raw material comprises C.sub.1-C.sub.6 hydrocarbon compounds; the hydrocarbon compounds are at least one selected from the group consisting of C.sub.1-C.sub.6 alkanes and C.sub.1-C.sub.6 olefins; the coke control raw material further comprises at least one selected from the group consisting of hydrogen, an alcohol compound, and water; and a proportion of a total mass of the alcohol compound and the water in a mass of the coke control raw material is greater than or equal to 10 wt % and less than or equal to 50 wt %; the alcohol compound is at least one selected from the group consisting of methanol and ethanol; and the coke control raw material comprises 0 wt % to 20 wt % of hydrogen, 0 wt % to 50 wt % of methane, 0 wt % to 50 wt % of ethane, 0 wt % to 20 wt % of ethylene, 0 wt % to 50 wt % of propane, 0 wt % to 20 wt % of propylene, 0 wt % to 90 wt % of butane, 0 wt % to 90 wt % of butene, 0 wt % to 90 wt % of pentane, 0 wt % to 90 wt % of pentene, 0 wt % to 90 wt % of hexane, 0 wt % to 90 wt % of hexene, 0 wt % to 50 wt % of methanol, 0 wt % to 50 wt % of ethanol, and 0 wt % to 50 wt % of water; and a total amount of the hydrocarbon compounds is greater than 0%.

37. The method according to claim 29, wherein the catalyst comprises an SAPO molecular sieve; a coke content in the catalyst is less than or equal to 3 wt %; a coke content in the coke controlled catalyst is 4 wt % to 9 wt %; and a quartile deviation of a coke content distribution in the coke controlled catalyst is less than 1 wt %.

38. The method according to claim 29, wherein coke species in the coke controlled catalyst comprise polymethylbenzene and polymethylnaphthalene; a total mass of the polymethylbenzene and the polymethylnaphthalene accounts for greater than or equal to 70 wt % of a total mass of coke; a mass of coke species with a molecular weight greater than 184 accounts for less than or equal to 25 wt % of the total mass of coke; and the total mass of coke refers to a total mass of coke species.

39. The method according to claim 35, wherein a coke content in the spent catalyst is 9 wt % to 13 wt %.

40. The method according to claim 35, wherein the oxygen-containing compound is at least one selected from the group consisting of methanol and dimethyl ether (DME).

41. The method according to claim 29, wherein process conditions of the coke control zone are as follows: apparent gas linear velocity: 0.1 m/s to 0.5 m/s; reaction temperature: 300° C. to 700° C.; reaction pressure: 100 kPa to 500 kPa; and bed density: 400 kg/m.sup.3 to 800 kg/m.sup.3.

42. The method according to claim 35, wherein process conditions of the reaction zone are as follows: apparent gas linear velocity: 0.5 m/s to 2.0 m/s; reaction temperature: 350° C. to 550° C.; reaction pressure: 100 kPa to 500 kPa; and bed density: 150 kg/m.sup.3 to 500 kg/m.sup.3.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0090] FIG. 1 is a schematic diagram of a DMTO device for preparing low-carbon olefins from an oxygen-containing compound according to an embodiment of the present application; and

[0091] FIG. 2 is a schematic diagram of a cross section of a coke control zone of the fluidized bed reactor according to an embodiment of the present application.

LIST OF REFERENCE NUMERALS

[0092] 1 represents a fluidized bed reactor; 1-1 represents a main shell; 1-2 represents a reaction zone distributor;

[0093] 1-3 represents a fluidized bed reactor cooler; 1-4 represents a coke control zone distributor;

[0094] 1-5 represents a baffle; 1-6 represents a first gas-solid separation unit;

[0095] 1-7 represents a coke controlled catalyst delivery pipe; 1-8 represents a coke control zone gas delivery pipe;

[0096] 1-9 represents a second gas-solid separation unit; 1-10 represents a first gas collection chamber;

[0097] 1-11 represents a product gas delivery pipe; 1-12 represents a first stripper;

[0098] 1-13 represents a spent catalyst slide valve; 1-14 represents a spent catalyst delivery pipe;

[0099] 2 represents a fluidized bed regenerator; 2-1 represents a regenerator shell; 2-2 represents a regeneration zone distributor;

[0100] 2-3 represents a third gas-solid separation unit; 2-4 represents a second gas collection chamber;

[0101] 2-5 represents a flue gas delivery pipe; 2-6 represents a second stripper; 2-7 represents a regenerator cooler;

[0102] 2-8 represents a regenerated catalyst slide valve; and 2-9 represents a regenerated catalyst delivery pipe.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0103] The present application will be described in detail below with reference to examples, but the present application is not limited to these examples.

[0104] Possible embodiments are described below.

[0105] In order to improve the performance of a DMTO catalyst, the present application provides a method for on-line modification of a DMTO catalyst through a coke control reaction, including the following steps:

[0106] a) a regenerated catalyst is delivered to a coke control zone;

[0107] b) a coke control raw material including hydrogen, methane, ethane, ethylene, propane, propylene, butane, butene, pentane, pentene, hexane, hexene, methanol, ethanol, and water is delivered to a coke control reactor;

[0108] (c) the coke control raw material contacts and reacts with the regenerated catalyst in the coke control reactor, such that the coke control raw material is coked on the regenerated catalyst, where a coked catalyst is called a coke controlled catalyst; a coke content in the coke controlled catalyst is 4 wt % to 9 wt %; coke species include polymethylbenzene and polymethylnaphthalene, and a total mass of the polymethylbenzene and the polymethylnaphthalene accounts for greater than or equal to 70 wt % of a total mass of coke; and a mass of coke species with a molecular weight greater than 184 accounts for less than or equal to 25 wt % of the total mass of coke; and

[0109] d) the coke controlled catalyst is delivered to a methanol conversion reactor. The regenerated catalyst may be a DMTO catalyst with a coke content of less than or equal to 3 wt %, and an active component of the DMTO catalyst may be an SAPO molecular sieve.

[0110] The coke control raw material may be composed of 0 wt % to 20 wt % of hydrogen, 0 wt % to 50 wt % of methane, 0 wt % to 50 wt % of ethane, 0 wt % to 20 wt % of ethylene, 0 wt % to 50 wt % of propane, 0 wt % to 20 wt % of propylene, 0 wt % to 90 wt % of butane, 0 wt % to 90 wt % of butene, 0 wt % to 90 wt % of pentane, 0 wt % to 90 wt % of pentene, 0 wt % to 90 wt % of hexane, 0 wt % to 90 wt % of hexene, 0 wt % to 50 wt % of methanol, 0 wt % to 50 wt % of ethanol, and 0 wt % to 50 wt % of water, and a total content of methanol, ethanol, and water may be greater than or equal to 10 wt %.

[0111] A reaction temperature of the coke control reaction may be 300° C. to 700° C. The present application also provides a method for preparing low-carbon olefins from an oxygen-containing compound that includes the method for on-line modification of a DMTO catalyst through a coke control reaction described above, and a device used thereby. The device includes a fluidized bed reactor 1 and a fluidized bed regenerator 2.

[0112] The fluidized bed reactor 1 is divided into a reaction zone, a coke control zone, and a gas-solid separation zone from bottom to top; the fluidized bed reactor 1 includes a fluidized bed reactor main shell 1-1, a reaction zone distributor 1-2, a fluidized bed reactor cooler 1-3, a coke control zone distributor 1-4, a baffle 1-5, a first gas-solid separation unit 1-6, a coke controlled catalyst delivery pipe 1-7, a coke control zone gas delivery pipe 1-8, a second gas-solid separation unit 1-9, a first gas collection chamber 1-10, a product gas delivery pipe 1-11, a first stripper 1-12, a spent catalyst slide valve 1-13, and a spent catalyst delivery pipe 1-14; and the spent catalyst slide valve 1-13 is configured to control a circulation volume of a spent catalyst.

[0113] The reaction zone distributor 1-2 is located at a bottom of the reaction zone of the fluidized bed reactor 1, and the fluidized bed reactor cooler 1-3 is located in the reaction zone.

[0114] The coke control zone is located in an annular zone above the reaction zone, n baffles 1-5 are arranged in the coke control zone, and the baffles 1-5 divide the coke control zone into n coke control zone subzones, where n is an integer and 2≤n≤10; a bottom of each of the coke control zone subzones is independently provided with a coke control zone distributor 1-4; a cross section of the coke control zone is annular, and a cross section of each of the coke control zone subzones is sector-annular; the 1.sup.st to n.sup.th coke control zone subzones are concentrically arranged in sequence; and a catalyst circulation hole is formed in the baffles 1-5, but no catalyst circulation hole is formed in a baffle shared by the 1.sup.st coke control zone subzone and the n.sup.th coke control zone subzone.

[0115] The first gas-solid separation unit 1-6 is located in the gas-solid separation zone of the fluidized bed reactor 1; an inlet of the first gas-solid separation unit 1-6 is connected to an outlet of the regenerated catalyst delivery pipe 2-9, a gas outlet of the first gas-solid separation unit 1-6 is formed in the gas-solid separation zone, and a catalyst outlet of the first gas-solid separation unit 1-6 is formed in the 1.sup.st coke control zone subzone; and an inlet of the coke controlled catalyst delivery pipe 1-7 is connected to the n.sup.th coke control zone subzone, and an outlet of the coke controlled catalyst delivery pipe 1-7 is formed in the reaction zone.

[0116] A top of each of the coke control zone subzones is independently provided with a coke control zone gas delivery pipe 1-8, and an outlet of the coke control zone gas delivery pipe 1-8 is formed in the gas-solid separation zone; the second gas-solid separation unit 1-9 and the first gas collection chamber 1-10 are located in the gas-solid separation zone of the fluidized bed reactor 1; an inlet of the second gas-solid separation unit 1-9 is formed in the gas-solid separation zone of the fluidized bed reactor 1, a gas outlet of the second gas-solid separation unit 1-9 is connected to the first gas collection chamber 1-10, and a catalyst outlet of the second gas-solid separation unit 1-9 is formed in the reaction zone; the product gas delivery pipe 1-11 is connected to a top of the first gas collection chamber 1-10; the first stripper 1-12 is located below the fluidized bed reactor 1, an inlet pipe of the first stripper 1-12 penetrates through a lower fluidized bed reactor shell through the bottom of the fluidized bed reactor 1 and is opened above the reaction zone distributor 1-2; and an inlet of the spent catalyst slide valve 1-13 is connected to an outlet pipe at a bottom of the first stripper 1-12, an outlet of the spent catalyst slide valve 1-13 is connected to an inlet of the spent catalyst delivery pipe 1-14 through a pipeline, and an outlet of the spent catalyst delivery pipe 1-14 is connected to a middle part of the fluidized bed regenerator 2.

[0117] In a preferred embodiment, the first gas-solid separation unit 1-6 may be a gas-solid cyclone separator.

[0118] In a preferred embodiment, the first gas-solid separation unit 1-6 may be a gas-solid rapid separator.

[0119] In a preferred embodiment, the second gas-solid separation unit 1-9 may adopt one or more sets of gas-solid cyclone separators, and each set of gas-solid cyclone separators may include a first-stage gas-solid cyclone separator and a second-stage gas-solid cyclone separator.

[0120] A device for preparing low-carbon olefins from an oxygen-containing compound is provided, where the device includes a fluidized bed regenerator 2 for regenerating a catalyst; the fluidized bed regenerator 2 includes a regenerator shell 2-1, a regeneration zone distributor 2-2, a third gas-solid separation unit 2-3, a second gas collection chamber 2-4, a flue gas delivery pipe 2-5, a second stripper 2-6, a regenerator cooler 2-7, a regenerated catalyst slide valve 2-8, and a regenerated catalyst delivery pipe 2-9;

[0121] the regeneration zone distributor 2-2 is located at a bottom of the fluidized bed regenerator 2, and the third gas-solid separation unit 2-3 is located at an upper part of the fluidized bed regenerator 2; an inlet of the third gas-solid separation unit 2-3 is formed in an upper part of the fluidized bed regenerator 2, a gas outlet of the third gas-solid separation unit 2-3 is connected to the second gas collection chamber 2-4, and a catalyst outlet of the third gas-solid separation unit 2-3 is formed in a lower part of the fluidized bed regenerator 2; the second gas collection chamber 2-4 is located at a top of the fluidized bed regenerator 2, and the flue gas delivery pipe 2-5 is connected to a top of the second gas collection chamber 2-4;

[0122] the second stripper 2-6 is located outside the regenerator shell 2-1, and an inlet pipe of the second stripper 2-6 penetrates through the regenerator shell 2-1 and is opened above the regeneration zone distributor 2-2; the regenerator cooler 2-7 is located in the second stripper 2-6; and an inlet of the regenerated catalyst slide valve 2-8 is connected to a bottom of the second stripper 2-6 through a pipeline, an outlet of the regenerated catalyst slide valve 2-8 is connected to an inlet of the regenerated catalyst delivery pipe 2-9 through a pipeline, and an outlet of the regenerated catalyst delivery pipe 2-9 is connected to an inlet of the first gas-solid separation unit 1-6. The regenerated catalyst slide valve 2-8 is configured to control a circulation volume of a regenerated catalyst.

[0123] In a preferred embodiment, the third gas-solid separation unit 2-3 may adopt one or more sets of gas-solid cyclone separators, and each set of gas-solid cyclone separators may include a first-stage gas-solid cyclone separator and a second-stage gas-solid cyclone separator.

[0124] According to another aspect of the present application, an MTO method including the method for on-line modification of a DMTO catalyst through a coke control reaction is also provided, including the following steps:

[0125] a coke control raw material is fed into the coke control zone of the fluidized bed reactor 1 from the coke control zone distributor 1-4; a regenerated catalyst is fed into the first gas-solid separation unit 1-6 from the regenerated catalyst delivery pipe 2-9 to undergo gas-solid separation, a resulting gas is discharged into the gas-solid separation zone of the fluidized bed reactor 1 through the gas outlet of the first gas-solid separation unit 1-6, and a resulting regenerated catalyst is discharged into the coke control zone ofthe fluidized bed reactor 1 through the catalyst outlet of the first gas-solid separation unit 1-6; the coke control raw material contacts and chemically reacts with the regenerated catalyst in the coke control zone to generate a coke controlled catalyst and a coke control product gas; the coke controlled catalyst passes through the 1.sup.st to n.sup.th coke control zone subzones in sequence through the catalyst circulation holes on the baffles 1-5, and then enters the reaction zone of the fluidized bed reactor 1 through the coke controlled catalyst delivery pipe 1-7; the coke control product gas enters the gas-solid separation zone of the fluidized bed reactor 1 through the coke control zone gas delivery pipe 1-8; a raw material with an oxygen-containing compound is fed into the reaction zone of the fluidized bed reactor 1 from the reaction zone distributor 1-2 to contact the coke controlled catalyst to generate a stream A with low-carbon olefins and a spent catalyst; the stream A and the coke control product gas are mixed in the gas-solid separation zone to produce a stream B, and the stream B enters the second gas-solid separation unit 1-9 to undergo gas-solid separation to obtain a gas-phase stream C and a solid-phase stream D, where the gas-phase stream C is a low-carbon olefin-containing product gas and the solid-phase stream D is a spent catalyst; the gas-phase stream C enters the first gas collection chamber 1-10, and then enters a downstream working section through the product gas delivery pipe 1-11, and the solid-phase stream D is returned to the reaction zone of the fluidized bed reactor 1; the spent catalyst in the reaction zone enters the fluidized bed reactor stripper 1-12 through the inlet pipe of the first stripper 1-12 to undergo stripping, and then enters a middle part of the fluidized bed regenerator 2 through the spent catalyst slide valve 1-13 and the spent catalyst delivery pipe 1-14;

[0126] a regeneration gas is fed from the regeneration zone distributor 2-2 to the bottom of the fluidized bed regenerator 2, and in the fluidized bed regenerator 2, the regeneration gas contacts and chemically reacts with the spent catalyst, such that a part of coke in the spent catalyst is burned and eliminated to generate a stream E with a flue gas and a regenerated catalyst; the stream E enters the third gas-solid separation unit 2-3 to undergo gas-solid separation to obtain a flue gas and a regenerated catalyst; the flue gas enters the second gas collection chamber 2-4, and then enters a downstream flue gas treatment system through the flue gas delivery pipe 2-5; the regenerated catalyst is returned to the bottom of the fluidized bed regenerator 2; and the regenerated catalyst in the fluidized bed regenerator 2 enters the second stripper 2-6 to be stripped and cooled, and then enters the first gas-solid separation unit 1-6 through the regenerated catalyst slide valve 2-8 and the regenerated catalyst delivery pipe 2-9.

[0127] In a preferred embodiment, the coke control raw material of the present application may be composed of 0 wt % to 20 wt % of hydrogen, 0 wt % to 50 wt % of methane, 0 wt % to 50 wt % of ethane, 0 wt % to 20 wt % of ethylene, 0 wt % to 50 wt % of propane, 0 wt % to 20 wt % of propylene, 0 wt % to 90 wt % of butane, 0 wt % to 90 wt % of butene, 0 wt % to 90 wt % of pentane, 0 wt % to 90 wt % of pentene, 0 wt % to 90 wt % of hexane, 0 wt % to 90 wt % of hexene, 0 wt % to 50 wt % of methanol, 0 wt % to 50 wt % of ethanol, and 0 wt % to 50 wt % of water, and a total content of methanol, ethanol, and water may be greater than or equal to 10 wt %.

[0128] In a preferred embodiment, the oxygen-containing compound in the method of the present application may be one from the group consisting of methanol, DME, and a mixture of methanol and DME.

[0129] In a preferred embodiment, the regeneration gas in the method of the present application may be 0 wt % to 100 wt % air, 0 wt % to 50 wt % oxygen, 0 wt % to 50 wt % nitrogen, and 0 wt % to 50 wt % water vapor.

[0130] In a preferred embodiment, an active component of the catalyst may be an SAPO molecular sieve.

[0131] In a preferred embodiment, a coke content in the regenerated catalyst may be less than or equal to 3 wt %.

[0132] In a preferred embodiment, a coke content in the coke controlled catalyst may be 4 wt % to 9 wt %, and a quartile deviation of coke content distribution in the coke controlled catalyst may be less than 1 wt %; coke species may include polymethylbenzene and polymethylnaphthalene, and a total mass of the polymethylbenzene and the polymethylnaphthalene may account for greater than or equal to 70 wt % of a total mass of coke; and a mass of coke species with a molecular weight greater than 184 may account for less than or equal to 25 wt % of the total mass of coke.

[0133] In a preferred embodiment, a coke content in the spent catalyst may be 9 wt % to 13 wt %, and further preferably, the coke content in the spent catalyst may be 10 wt % to 12 wt %.

[0134] In a preferred embodiment, process operating conditions of the coke control zone of the fluidized bed reactor 1 may be as follows: apparent gas linear velocity: 0.1 m/s to 0.5 m/s; reaction temperature: 300° C. to 700° C.; reaction pressure: 100 kPa to 500 kPa; and bed density: 400 kg/m.sup.3 to 800 kg/m.sup.3.

[0135] In a preferred embodiment, process operating conditions of the reaction zone of the fluidized bed reactor 1 may be as follows: apparent gas linear velocity: 0.5 m/s to 2.0 m/s; reaction temperature: 350° C. to 550° C.; reaction pressure: 100 kPa to 500 kPa; and bed density: 150 kg/m.sup.3 to 500 kg/m.sup.3.

[0136] In a preferred embodiment, process operating conditions of the fluidized bed regenerator 2 may be as follows: apparent gas linear velocity: 0.5 m/s to 2.0 m/s; regeneration temperature: 600° C. to 750° C.; regeneration pressure: 100 kPa to 500 kPa; and bed density: 150 kg/m.sup.3 to 700 kg/m.sup.3.

[0137] In the method of the present application, the product gas may be composed of 38 wt % to 57 wt % of ethylene, 37 wt % to 55 wt % of propylene, less than or equal to 5 wt % of C.sub.4-C.sub.6 hydrocarbon compounds, and less than or equal to 3 wt % of other components; and the other components may be methane, ethane, propane, hydrogen, CO, CO.sub.2, and the like, and the total selectivity of ethylene and propylene in the product gas may be 93 wt % to 96 wt %.

[0138] In the present application, when the production unit consumption is expressed, a mass of DME in the oxygen-containing compound is equivalently converted into a mass of methanol based on a mass of the element C, and a unit of the production unit consumption is ton of methanol/ton of low-carbon olefins.

[0139] In the method of the present application, the production unit consumption may be 2.50 to 2.58 tons of methanol/ton of low-carbon olefins.

EXAMPLE 1

[0140] The device shown in FIG. 1 and FIG. 2 is adopted in this example, where 2 baffles are arranged in the coke control zone in the fluidized bed reactor, that is, n=2; the coke control zone includes 2 coke control zone subzones; and the first gas-solid separation unit is a gas-solid cyclone separator.

[0141] Specifically, as shown in FIG. 1, a diameter of a junction between the lower shell and the upper shell gradually increases from bottom to top, such that a diameter of the gas-solid separation zone is larger than a diameter of the reaction zone. The coke control zone is located at the junction of the lower shell and the upper shell. A longitudinal cross section of each of the baffles is in a parallelogram.

[0142] In this example, the coke control raw material is a mixture of 6 wt % of butane, 81 wt % of butene, 2 wt % of methanol, and 11 wt % of water; the oxygen-containing compound is methanol; the regeneration gas is air; an active component in the catalyst is an SAPO-34 molecular sieve; a coke content in the regenerated catalyst is about 1 wt %; a coke content in the coke controlled catalyst is about 4 wt %, where a total mass of polymethylbenzene and polymethylnaphthalene accounts for about 85 wt % of a total mass of coke, a mass of coke species with a molecular weight greater than 184 accounts for about 6 wt % of the total mass of coke, and a quartile deviation of a coke content distribution in the coke controlled catalyst is about 0.9 wt %; and a coke content in the spent catalyst is about 9 wt %.

[0143] Process operating conditions of the coke control zone of the fluidized bed reactor are as follows: apparent gas linear velocity: about 0.3 m/s, reaction temperature: about 500° C., reaction pressure: about 100 kPa, and bed density: about 600 kg/m.sup.3.

[0144] Process operating conditions of the reaction zone of the fluidized bed reactor are as follows: apparent gas linear velocity: about 2.0 m/s, reaction temperature: about 550° C., reaction pressure: about 100 kPa, and bed density: about 150 kg/m.sup.3.

[0145] Process operating conditions of the fluidized bed regenerator are as follows: apparent gas linear velocity: about 0.5 m/s; regeneration temperature: about 700° C.; regeneration pressure: about 100 kPa; and bed density: about 700 kg/m.sup.3.

[0146] In this example, the product gas is composed of 57 wt % of ethylene, 37 wt % of propylene, 3 wt % of C.sub.4-C.sub.6 hydrocarbon compounds, and 3 wt % of other components, where the other components include methane, ethane, propane, hydrogen, CO, CO.sub.2, and the like; and the production unit consumption is 2.55 tons of methanol/ton of low-carbon olefins.

EXAMPLE 2

[0147] The device shown in FIG. 1 and FIG. 2 is adopted in this example, where 10 baffles are arranged in the coke control zone in the fluidized bed reactor, that is, n=10; the coke control zone includes 10 coke control zone subzones; and the first gas-solid separation unit is a gas-solid cyclone separator.

[0148] In this example, the coke control raw material is a mixture of 22 wt % of methane, 24 wt % of ethane, 3 wt % of ethylene, 28 wt % of propane, 4 wt % of propylene, 7 wt % of hydrogen, and 12 wt % of water; the oxygen-containing compound is a mixture of 82 wt % of methanol and 18 wt % of DME; the regeneration gas is a mixture of 50 wt % of air and 50 wt % of water vapor; an active component in the catalyst is an SAPO-34 molecular sieve; a coke content in the regenerated catalyst is about 3 wt %; a coke content in the coke controlled catalyst is about 9 wt %, where a total mass of polymethylbenzene and polymethylnaphthalene accounts for about 78 wt % of a total mass of coke, a mass of coke species with a molecular weight greater than 184 accounts for about 13 wt % of the total mass of coke, and a quartile deviation of a coke content distribution in the coke controlled catalyst is about 0.2 wt %; and a coke content in the spent catalyst is about 13 wt %.

[0149] Process operating conditions of the coke control zone of the fluidized bed reactor are as follows: apparent gas linear velocity: about 0.1 m/s, reaction temperature: about 300° C., reaction pressure: about 500 kPa, and bed density: about 800 kg/m.sup.3.

[0150] Process operating conditions of the reaction zone of the fluidized bed reactor are as follows: apparent gas linear velocity: about 0.5 m/s, reaction temperature: about 350° C., reaction pressure: about 500 kPa, and bed density: about 500 kg/m.sup.3.

[0151] Process operating conditions of the fluidized bed regenerator are as follows: apparent gas linear velocity: about 2.0 m/s; regeneration temperature: about 600° C.; regeneration pressure: about 500 kPa; and bed density: about 150 kg/m.sup.3.

[0152] In this example, the product gas is composed of 38 wt % of ethylene, 55 wt % of propylene, 5 wt % of C.sub.4-C.sub.6 hydrocarbon compounds, and 2 wt % of other components, where the other components include methane, ethane, propane, hydrogen, CO, CO.sub.2, and the like; and the production unit consumption is 2.58 tons of methanol/ton of low-carbon olefins.

EXAMPLE 3

[0153] The device shown in FIG. 1 and FIG. 2 is adopted in this example, where 4 baffles are arranged in the coke control zone in the fluidized bed reactor, that is, n=4; the coke control zone includes 4 coke control zone subzones; and the first gas-solid separation unit is a gas-solid rapid separator.

[0154] In this example, the coke control raw material is a mixture of 1 wt % of propane, 1 wt % of propylene, 3 wt % of butane, 51 wt % of butene, 3 wt % of pentane, 22 wt % of pentene, 1 wt % of hexane, 7 wt % of hexene, 2 wt % of methanol, and 9 wt % of water; the oxygen-containing compound is DME; the regeneration gas is a mixture of 50 wt % of air and 50 wt % of oxygen; an active component in the catalyst is an SAPO-34 molecular sieve; a coke content in the regenerated catalyst is about 2 wt %; a coke content in the coke controlled catalyst is about 6 wt %, where a total mass of polymethylbenzene and polymethylnaphthalene accounts for about 81 wt % of a total mass of coke, a mass of coke species with a molecular weight greater than 184 accounts for about 15 wt % of the total mass of coke, and a quartile deviation of a coke content distribution in the coke controlled catalyst is about 0.6 wt %; and a coke content in the spent catalyst is about 11 wt %.

[0155] Process operating conditions of the coke control zone of the fluidized bed reactor are as follows: apparent gas linear velocity: about 0.4 m/s, reaction temperature: about 700° C., reaction pressure: about 300 kPa, and bed density: about 500 kg/m.sup.3.

[0156] Process operating conditions of the reaction zone of the fluidized bed reactor are as follows: apparent gas linear velocity: about 1.0 m/s, reaction temperature: about 450° C., reaction pressure: about 300 kPa, and bed density: about 300 kg/m.sup.3.

[0157] Process operating conditions of the fluidized bed regenerator are as follows: apparent gas linear velocity: about 1.0 m/s; regeneration temperature: about 750° C.; regeneration pressure: about 300 kPa; and bed density: about 360 kg/m.sup.3.

[0158] In this example, the product gas is composed of 48 wt % of ethylene, 47 wt % of propylene, 3 wt % of C.sub.4-C.sub.6 hydrocarbon compounds, and 2 wt % of other components, where the other components include methane, ethane, propane, hydrogen, CO, CO.sub.2, and the like; and the production unit consumption is 2.53 tons of methanol/ton of low-carbon olefins.

EXAMPLE 4

[0159] The device shown in FIG. 1 and FIG. 2 is adopted in this example, where 6 baffles are arranged in the coke control zone in the fluidized bed reactor, that is, n=6; the coke control zone includes 6 coke control zone subzones; and the first gas-solid separation unit is a gas-solid rapid separator.

[0160] In this example, the coke control raw material is a mixture of 5 wt % of butane, 72 wt % of butene, 8 wt % of methanol, and 15 wt % of water; the oxygen-containing compound is methanol; the regeneration gas is a mixture of 50 wt % of air and 50 wt % of nitrogen; an active component in the catalyst is an SAPO-34 molecular sieve; a coke content in the regenerated catalyst is about 2 wt %; a coke content in the coke controlled catalyst is about 6 wt %, where a total mass of polymethylbenzene and polymethylnaphthalene accounts for about 70 wt % of a total mass of coke, a mass of coke species with a molecular weight greater than 184 accounts for about 24 wt % of the total mass of coke, and a quartile deviation of a coke content distribution in the coke controlled catalyst is about 0.3 wt %; and a coke content in the spent catalyst is about 12 wt %.

[0161] Process operating conditions of the coke control zone of the fluidized bed reactor are as follows: apparent gas linear velocity: about 0.5 m/s, reaction temperature: about 600° C., reaction pressure: about 200 kPa, and bed density: about 400 kg/m.sup.3.

[0162] Process operating conditions of the reaction zone of the fluidized bed reactor are as follows: apparent gas linear velocity: about 1.5 m/s, reaction temperature: about 500° C., reaction pressure: about 200 kPa, and bed density: about 200 kg/m.sup.3.

[0163] Process operating conditions of the fluidized bed regenerator are as follows: apparent gas linear velocity: about 1.5 m/s; regeneration temperature: about 680° C.; regeneration pressure: about 200 kPa; and bed density: about 280 kg/m.sup.3.

[0164] In this example, the product gas is composed of 53 wt % of ethylene, 43 wt % of propylene, 3 wt % of C.sub.4-C.sub.6 hydrocarbon compounds, and 1 wt % of other components, where the other components include methane, ethane, propane, hydrogen, CO, CO.sub.2, and the like; and the production unit consumption is 2.50 tons of methanol/ton of low-carbon olefins.

COMPARATIVE EXAMPLE

[0165] This comparative example is different from Example 4 in that, the coke control reaction is not used for on-line modification of the DMTO catalyst; and the raw material fed into the coke control zone is nitrogen, which is an inert gas and does not change the properties of the regenerated catalyst in the coke control zone, that is, a catalyst entering the reaction zone is the regenerated catalyst.

[0166] In this example, the product gas is composed of 43 wt % of ethylene, 39 wt % of propylene, 12 wt % of C.sub.4-C.sub.6 hydrocarbon compounds, and 6 wt % of other components, where the other components include methane, ethane, propane, hydrogen, CO, CO.sub.2, and the like; and the production unit consumption is 2.91 tons of methanol/ton of low-carbon olefins.

[0167] This comparative example shows that the on-line modification of a DMTO catalyst through a coke control reaction can greatly improve the performance of the catalyst and reduce the production unit consumption.

[0168] The above examples are merely few examples of the present application, and do not limit the present application in any form. Although the present application is disclosed as above with preferred examples, the present application is not limited thereto. Some changes or modifications made by any technical personnel familiar with the profession using the technical content disclosed above without departing from the scope of the technical solutions of the present application are equivalent to equivalent implementation cases and fall within the scope of the technical solutions.