Patent Description:
Methanol-to-olefin technology (MTO) mainly includes DMTO (methanol-to-olefin) technology of Dalian Institute of Chemical Physics, Chinese Academy of Sciences and MTO technology of UOP Company of the United States. In <NUM>, the Shenhua Baotou methanol-to-olefin plant using DMTO technology was completed and put into operation. This is the world's first industrial application of MTO technology. As of the end of <NUM>, <NUM> DMTO industrial plants have been put into production, with a total production capacity of about <NUM> million tons of low-carbon olefins per year.

In recent years, DMTO technology has been further developed, and a new generation of DMTO catalyst with better performance have gradually begun industrial applications, creating higher benefits for DMTO plants. The new generation of DMTO catalyst has higher methanol processing capacity and low-carbon olefin selectivity. It is difficult for the existing DMTO industrial devices to take full advantage of the advantages of the new generation of DMTO catalyst. Therefore, it is necessary to develop a DMTO device and production method that can meet the needs of a new generation of DMTO catalyst with high methanol processing capacity and high selectivity of low-carbon olefins.

<CIT> discloses a method for producing oxygen contain low carbon olefins from light olefins, by using a reactor with a lower and upper part with a riser reactor and fluidized bed reactor zones surrounding said riser reactor, and a regenerator provided with a delivery tube. However, it does not provide a method for real-time continuous modification of a DMTO catalyst.

According to an aspect of the present application, a coke control reactor is provided, which can achieve the on-line modification of a DMTO catalyst; and the modification in the present application refers to controlling the coke content, coke content distribution, and coke species in the DMTO catalyst to improve the activity of the DMTO catalyst and the selectivity for low-carbon olefins.

A major characteristic of a DMTO catalyst is that the low-carbon olefin selectivity in a methanol conversion process increases with the increase of a coke content in the catalyst. The low-carbon olefins mentioned in the present application refer to ethylene and propylene.

The applicants have found through research that main factors affecting the activity of a DMTO catalyst and the selectivity for low-carbon olefins include coke content, coke content distribution, and coke species in the catalyst. Under the same average coke content in catalysts, the narrower the coke content distribution, the higher the selectivity and activity of low-carbon olefins. Coke species in a catalyst may include polymethyl aromatic hydrocarbon compounds, polymethyl cycloalkanes, and the like, where polymethylbenzene and polymethylnaphthalene can promote the formation of ethylene. Therefore, the control of the coke content, coke content distribution, and coke species in a catalyst is the key to control the activity of the DMTO catalyst and improve the selectivity of low-carbon olefins.

Possible beneficial effects of the present application:.

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

Unless otherwise specified, the raw materials and catalysts in the examples of the present application are all purchased from commercial sources.

The DMTO catalyst used in the examples of the present application is from Zhongke Catalysis (Dalian) Co.

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:.

A reaction temperature of the coke control reaction may be <NUM> to <NUM>.

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 coke control reactor <NUM>, a methanol conversion reactor <NUM>, and a regenerator <NUM>.

The coke control reactor <NUM> can realize the on-line modification of a DMTO catalyst through a coke control reaction, including: a coke control reactor shell <NUM>-<NUM>, a coke control reactor distributor <NUM>-<NUM>, a baffle <NUM>-<NUM>, a coke controlled catalyst delivery pipe <NUM>-<NUM>, a coke controlled catalyst slide valve <NUM>-<NUM>, and a coke control product gas delivery pipe <NUM>-<NUM>; the coke control reactor <NUM> is divided into a reaction zone I, a transition zone, and a coke controlled catalyst settling zone from bottom to top, respectively; n baffles <NUM>-<NUM> are arranged in the reaction zone I, bottoms of the baffles <NUM>-<NUM> are connected to a bottom of the coke controlled reactor shell <NUM>-<NUM>, and tops of the baffles <NUM>-<NUM> are located in the transition zone, where n is an integer and <NUM> ≤ n ≤ <NUM>; the baffles <NUM>-<NUM> divide the reaction zone I into m reaction zone I subzones, where m is an integer and <NUM> ≤ m ≤ <NUM>; a bottom of each of the reaction zone I subzones is independently provided with a coke control reactor distributor <NUM>-<NUM>, and m coke control reactor distributors <NUM>-<NUM> are arranged in the reaction zone I; an outlet of the regenerated catalyst delivery pipe <NUM>-<NUM> is connected to the <NUM>st reaction zone I subzone of the coke controlled reactor <NUM>, and an inlet of the coke controlled catalyst delivery pipe <NUM>-<NUM> is connected to the mth reaction zone I subzone of the coke control reactor <NUM>; a catalyst circulation hole is formed in each of the baffles <NUM>-<NUM>, and catalyst circulation holes on adjacent upper and lower baffles <NUM>-<NUM> are staggered; a coke controlled catalyst slide valve <NUM>-<NUM> is arranged in the coke controlled catalyst delivery pipe <NUM>-<NUM>, and an outlet of the coke controlled catalyst delivery pipe <NUM>-<NUM> is connected to a lower part of the methanol conversion reactor <NUM>; and an inlet of the coke control product gas delivery pipe <NUM>-<NUM> is connected to a top of the coke control reactor <NUM>, and an outlet of the coke control product gas delivery pipe <NUM>-<NUM> is connected to an upper part of the methanol conversion reactor <NUM>.

In a preferred embodiment, a cross section of the reaction zone I of the coke control reactor <NUM> may be rectangular, a cross section of the reaction zone I subzone may be rectangular, and the <NUM>st to mth reaction zone I subzones may be arranged from left to right in sequence.

In a preferred embodiment, a cross section of the reaction zone I of the coke control reactor <NUM> may be circular, and a cross section of a reaction zone I subzone may be fan-shaped; and the <NUM>st to mth reaction zone I subzones may be arranged concentrically in a clockwise or counterclockwise direction, and a baffle <NUM>-<NUM> shared by the <NUM>st reaction zone I subzone and the mth reaction zone I subzone of the coke control reactor <NUM> may not have catalyst circulation holes.

In a preferred embodiment, a cross section of the reaction zone I of the coke control reactor <NUM> may be annular, and a cross section of a reaction zone I subzone may be sector-annular; and the <NUM>st to mth reaction zone I subzones may be arranged concentrically in a clockwise or counterclockwise direction, and a baffle <NUM>-<NUM> shared by the <NUM>st reaction zone I subzone and the mth reaction zone I subzone of the coke control reactor <NUM> may not have catalyst circulation holes.

The coke control reactor <NUM> may be a bubbling fluidized bed reactor.

The methanol conversion reactor <NUM> includes a methanol conversion reactor shell <NUM>-<NUM>, a methanol conversion reactor distributor <NUM>-<NUM>, a delivery pipe <NUM>-<NUM>, a first gas-solid separation unit <NUM>-<NUM> of the methanol conversion reactor, a methanol conversion reactor gas collection chamber <NUM>-<NUM>, a spent catalyst zone gas distributor <NUM>-<NUM>, a methanol conversion reactor cooler <NUM>-<NUM>, a second gas-solid separation unit <NUM>-<NUM> of the methanol conversion reactor, a product gas delivery pipe <NUM>-<NUM>, a spent catalyst circulation pipe <NUM>-<NUM>, a spent catalyst circulation slide valve <NUM>-<NUM>, a spent catalyst inclined pipe <NUM>-<NUM>, a methanol conversion reactor stripper <NUM>-<NUM>, a spent catalyst slide valve <NUM>-<NUM>, and a spent catalyst delivery pipe <NUM>-<NUM>.

A lower part of the methanol conversion reactor <NUM> is a reaction zone II, a middle part thereof is a spent catalyst zone, and an upper part thereof is a gas-solid separation zone.

The methanol conversion reactor distributor <NUM>-<NUM> is located at a bottom of the reaction zone II of the methanol conversion reactor <NUM>; the delivery pipe <NUM>-<NUM> is located in central zones of the middle and upper parts of the methanol conversion reactor <NUM>; and a bottom end of the delivery pipe <NUM>-<NUM> is connected to a top end of the reaction zone II, and an upper part of the delivery pipe <NUM>-<NUM> is connected to an inlet of the first gas-solid separation unit <NUM>-<NUM> of the methanol conversion reactor.

The first gas-solid separation unit <NUM>-<NUM> of the methanol conversion reactor is located in the gas-solid separation zone of the methanol conversion reactor; and a gas outlet of the first gas-solid separation unit <NUM>-<NUM> of the methanol conversion reactor is connected to the methanol conversion reactor gas collection chamber <NUM>-<NUM>, and a catalyst outlet of the first gas-solid separation unit <NUM>-<NUM> of the methanol conversion reactor is formed in the spent catalyst zone.

The spent catalyst zone gas distributor <NUM>-<NUM> is located at a bottom of the spent catalyst zone, and the methanol conversion reactor cooler <NUM>-<NUM> is located in the spent catalyst zone.

The second gas-solid separation unit <NUM>-<NUM> of the methanol conversion reactor is located in the gas-solid separation zone of the methanol conversion reactor; an inlet of the second gas-solid separation unit <NUM>-<NUM> of the methanol conversion reactor is formed in the gas-solid separation zone of the methanol conversion reactor, a gas outlet of the second gas-solid separation unit <NUM>-<NUM> of the methanol conversion reactor is connected to the methanol conversion reactor gas collection chamber <NUM>-<NUM>, and a catalyst outlet of the second gas-solid separation unit <NUM>-<NUM> of the methanol conversion reactor is formed in the spent catalyst zone; the methanol conversion reactor gas collection chamber <NUM>-<NUM> is located at a top of the methanol conversion reactor <NUM>, and the product gas delivery pipe <NUM>-<NUM> is connected to a top of the methanol conversion reactor gas collection chamber <NUM>-<NUM>; an inlet of the spent catalyst circulation pipe <NUM>-<NUM> is connected to the spent catalyst zone, and an outlet of the spent catalyst circulation pipe <NUM>-<NUM> is connected to the bottom of the reaction zone II of the methanol conversion reactor; the spent catalyst circulation slide valve <NUM>-<NUM> is arranged in the spent catalyst circulation pipe <NUM>-<NUM>; an outlet of the coke controlled catalyst delivery pipe <NUM>-<NUM> is connected to the bottom of the reaction zone II of the methanol conversion reactor <NUM>, an inlet of the spent catalyst inclined pipe <NUM>-<NUM> is connected to the spent catalyst zone, and an outlet of the spent catalyst inclined pipe <NUM>-<NUM> is connected to an upper part of the methanol conversion reactor stripper <NUM>-<NUM>; the methanol conversion reactor stripper <NUM>-<NUM> is arranged outside the methanol conversion reactor shell <NUM>-<NUM>; and an inlet of the spent catalyst slide valve <NUM>-<NUM> is connected to a bottom of the methanol conversion reactor stripper <NUM>-<NUM> through a pipeline, an outlet of the spent catalyst slide valve <NUM>-<NUM> is connected to an inlet of the spent catalyst delivery pipe <NUM>-<NUM> through a pipeline, and an outlet of the spent catalyst delivery pipe <NUM>-<NUM> is connected to a middle part of the regenerator <NUM>.

In a preferred embodiment, the first gas-solid separation unit <NUM>-<NUM> of the methanol conversion reactor 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.

In a preferred embodiment, the second gas-solid separation unit <NUM>-<NUM> of the methanol conversion reactor 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.

The methanol conversion reactor <NUM> may be a fluidized bed reactor.

The regenerator <NUM> includes a regenerator shell <NUM>-<NUM>, a regenerator distributor <NUM>-<NUM>, a regenerator gas-solid separation unit <NUM>-<NUM>, a regenerator gas collection chamber <NUM>-<NUM>, a flue gas delivery pipe <NUM>-<NUM>, a regenerator stripper <NUM>-<NUM>, a regenerator cooler <NUM>-<NUM>, a regenerated catalyst slide valve <NUM>-<NUM>, and a regenerated catalyst delivery pipe <NUM>-<NUM>. The regenerator distributor <NUM>-<NUM> is located at a bottom of the regenerator <NUM>, and the regenerator gas-solid separation unit <NUM>-<NUM> is located at an upper part of the regenerator <NUM>; an inlet of the regenerator gas-solid separation unit <NUM>-<NUM> is formed at an upper part of the regenerator <NUM>, a gas outlet of the regenerator gas-solid separation unit <NUM>-<NUM> is connected to the regenerator gas collection chamber <NUM>-<NUM>, and a catalyst outlet of the regenerator gas-solid separation unit <NUM>-<NUM> is formed at a lower part of the regenerator <NUM>; the regenerator gas collection chamber <NUM>-<NUM> is located at a top of the regenerator <NUM>, and the flue gas delivery pipe <NUM>-<NUM> is connected to a top of the regenerator gas collection chamber <NUM>-<NUM>; the regenerator stripper <NUM>-<NUM> is located outside the regenerator shell <NUM>-<NUM>, and an inlet pipe of the regenerator stripper <NUM>-<NUM> penetrates through the regenerator shell <NUM>-<NUM> and is opened above the regenerator distributor <NUM>-<NUM>; the regenerator cooler <NUM>-<NUM> is located in the regenerator stripper <NUM>-<NUM>; and an inlet of the regenerated catalyst slide valve <NUM>-<NUM> is connected to a bottom of the regenerator stripper <NUM>-<NUM> through a pipeline, an outlet of the regenerated catalyst slide valve <NUM>-<NUM> is connected to an inlet of the regenerated catalyst delivery pipe <NUM>-<NUM> through a pipeline, and an outlet of the regenerated catalyst delivery pipe <NUM>-<NUM> is connected to the coke control reactor <NUM>.

In a preferred embodiment, the regenerator gas-solid separation unit <NUM>-<NUM> 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.

The regenerator <NUM> may be a fluidized bed reactor.

The present application also provides an MTO method including the method for on-line modification of a DMTO catalyst through a coke control reaction, including the following steps:.

In the method of the present application, the product gas may be composed of <NUM> wt% to <NUM> wt% of ethylene, <NUM> wt% to <NUM> wt% of propylene, less than or equal to <NUM> wt% of C<NUM>-C<NUM> hydrocarbon compounds, and less than or equal to <NUM> wt% of other components; and the other components may be methane, ethane, propane, hydrogen, CO, CO<NUM>, and the like, and the total selectivity of ethylene and propylene in the product gas may be <NUM> wt% to <NUM> wt%.

In the present application, when the unit consumption of production 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 unit consumption of production is ton of methanol/ton of low-carbon olefins.

In the method of the present application, the unit consumption of production may be <NUM> to <NUM> tons of methanol/ton of low-carbon olefins.

In order to well illustrate the present application and facilitate the understanding of the technical solutions of the present application, typical but non-limiting examples of the present application are as follows:.

In this example, the device shown in <FIG> is adopted, where a cross section of the reaction zone I of the coke control reactor <NUM> is rectangular; a cross section of the reaction zone I subzone is rectangular; n = <NUM> and m = <NUM>; and the <NUM>st and <NUM>nd reaction zone I subzones are arranged from left to right in sequence.

In this example, the coke control raw material is a mixture of <NUM> wt% of butane, <NUM> wt% of butene, <NUM> wt% of methanol, and <NUM> wt% of water; the oxygen-containing compound is methanol; the spent catalyst zone fluidizing gas is nitrogen; the regeneration gas is air; an active component in the catalyst is an SAPO-<NUM> molecular sieve; a coke content in the regenerated catalyst is about <NUM> wt%; a coke content in the coke controlled catalyst is about <NUM> wt%, where a total mass of polymethylbenzene and polymethylnaphthalene accounts for about <NUM> wt% of a total mass of coke, a mass of coke species with a molecular weight greater than <NUM> accounts for about <NUM> wt% of a total mass of coke, and a quartile deviation of coke content distribution in the coke controlled catalyst is about <NUM> wt%; a coke content in the spent catalyst is about <NUM> wt%; process operating conditions of the reaction zone I of the coke control reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; process operating conditions of the reaction zone II of the methanol conversion reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; process operating conditions of the spent catalyst zone of the methanol conversion reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; and process operating conditions of the regenerator <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, regeneration temperature: about <NUM>, regeneration pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>.

In this example, a WHSV of the oxygen-containing compound in the methanol conversion reactor is about <NUM>-<NUM>; the product gas is composed of <NUM> wt% of ethylene, <NUM> wt% of propylene, <NUM> wt% of C<NUM>-C<NUM> hydrocarbon compounds, and <NUM> wt% of other components, where the other components include methane, ethane, propane, hydrogen, CO, CO<NUM>, and the like; and the unit consumption of production is <NUM> tons of methanol/ton of low-carbon olefins.

In this example, the device shown in <FIG> is adopted, where a cross section of the reaction zone I of the coke control reactor <NUM> is rectangular; a cross section of the reaction zone I subzone is rectangular; n = <NUM> and m = <NUM>; and the <NUM>st to <NUM>th reaction zone I subzones are arranged from left to right in sequence.

In this example, the coke control raw material is a mixture of <NUM> wt% of methane, <NUM> wt% of ethane, <NUM> wt% of ethylene, <NUM> wt% of propane, <NUM> wt% of propylene, <NUM> wt% of hydrogen, and <NUM> wt% of water; the oxygen-containing compound is a mixture of <NUM> wt% of methanol and <NUM> wt% of DME; the spent catalyst zone fluidizing gas is water vapor; the regeneration gas is air; an active component in the catalyst is an SAPO-<NUM> molecular sieve; a coke content in the regenerated catalyst is about <NUM> wt%; a coke content in the coke controlled catalyst is about <NUM> wt%, where a total mass of polymethylbenzene and polymethylnaphthalene accounts for about <NUM> wt% of a total mass of coke, a mass of coke species with a molecular weight greater than184 accounts for about <NUM> wt% of a total mass of coke, and a quartile deviation of coke content distribution in the coke controlled catalyst is about <NUM> wt%; a coke content in the spent catalyst is about <NUM> wt%; process operating conditions of the reaction zone I of the coke control reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; process operating conditions of the reaction zone II of the methanol conversion reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; process operating conditions of the spent catalyst zone of the methanol conversion reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; and process operating conditions of the regenerator <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, regeneration temperature: about <NUM>, regeneration pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>.

In this example, the device shown in <FIG> is adopted, where a structure of the coke control reactor <NUM> is shown in <FIG>; a cross section of the reaction zone I of the coke control reactor of this example is circular, and a cross section of a reaction zone I subzone is fan-shaped; n = <NUM> and m = <NUM>; and the <NUM>st to <NUM>th reaction zone I subzones are arranged concentrically in a counterclockwise direction, and a baffle <NUM>-<NUM> shared by the <NUM>st reaction zone I subzone and the <NUM>th reaction zone I subzone of the coke control reactor does not have catalyst circulation holes.

In this example, the coke control raw material is a mixture of <NUM> wt% of propane, <NUM> wt% of propylene, <NUM> wt% of butane, <NUM> wt% of butene, <NUM> wt% of pentane, <NUM> wt% of pentene, <NUM> wt% of hexane, <NUM> wt% of hexene, <NUM> wt% of methanol, and <NUM> wt% of water; the oxygen-containing compound is DME; the spent catalyst zone fluidizing gas is nitrogen; the regeneration gas is a mixture of <NUM> wt% of air and <NUM> wt% of oxygen; an active component in the catalyst is an SAPO-<NUM> molecular sieve; a coke content in the regenerated catalyst is about <NUM> wt%; a coke content in the coke controlled catalyst is about <NUM> wt%, where a total mass of polymethylbenzene and polymethylnaphthalene accounts for about <NUM> wt% of a total mass of coke, a mass of coke species with a molecular weight greater than <NUM> accounts for about <NUM> wt% of a total mass of coke, and a quartile deviation of coke content distribution in the coke controlled catalyst is about <NUM> wt%; a coke content in the spent catalyst is about <NUM> wt%; process operating conditions of the reaction zone I of the coke control reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; process operating conditions of the reaction zone II of the methanol conversion reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; process operating conditions of the spent catalyst zone of the methanol conversion reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; and process operating conditions of the regenerator <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, regeneration temperature: about <NUM>, regeneration pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>.

In this example, the coke control raw material is a mixture of <NUM> wt% of butane, <NUM> wt% of butene, <NUM> wt% of methanol, and <NUM> wt% of water; the oxygen-containing compound is methanol; the spent catalyst zone fluidizing gas is water vapor; the regeneration gas is a mixture of <NUM> wt% of air and <NUM> wt% of nitrogen; an active component in the catalyst is an SAPO-<NUM> molecular sieve; a coke content in the regenerated catalyst is about <NUM> wt%; a coke content in the coke controlled catalyst is about <NUM> wt%, where a total mass of polymethylbenzene and polymethylnaphthalene accounts for about <NUM> wt% of a total mass of coke, a mass of coke species with a molecular weight greater than <NUM> accounts for about <NUM> wt% of a total mass of coke, and a quartile deviation of coke content distribution in the coke controlled catalyst is about <NUM> wt%; a coke content in the spent catalyst is about <NUM> wt%; process operating conditions of the reaction zone I of the coke control reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; process operating conditions of the reaction zone II of the methanol conversion reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; process operating conditions of the spent catalyst zone of the methanol conversion reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; and process operating conditions of the regenerator <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, regeneration temperature: about <NUM>, regeneration pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>.

In this example, the device shown in <FIG> is adopted, where a structure of the coke control reactor <NUM> is shown in <FIG>; a cross section of the reaction zone I of the coke control reactor of this example is annular, and a cross section of a reaction zone I subzone is sector-annular; n = <NUM> and m = <NUM>; and the <NUM>st to <NUM>th reaction zone I subzones are arranged concentrically in a clockwise direction, and a baffle <NUM>-<NUM> shared by the <NUM>st reaction zone I subzone and the <NUM>th reaction zone I subzone of the coke control reactor does not have catalyst circulation holes.

In this example, the coke control raw material is a mixture of <NUM> wt% of pentane, <NUM> wt% of pentene, <NUM> wt% of ethanol, and <NUM> wt% of water; the oxygen-containing compound is methanol; the spent catalyst zone fluidizing gas is a mixture of <NUM> wt% of nitrogen and <NUM> wt% of water vapor; the regeneration gas is a mixture of <NUM> wt% of air and <NUM> wt% of water vapor; an active component in the catalyst is an SAPO-<NUM> molecular sieve; a coke content in the regenerated catalyst is about <NUM> wt%; a coke content in the coke controlled catalyst is about <NUM> wt%, where a total mass of polymethylbenzene and polymethylnaphthalene accounts for about <NUM> wt% of a total mass of coke, a mass of coke species with a molecular weight greater than <NUM> accounts for about <NUM> wt% of a total mass of coke, and a quartile deviation of coke content distribution in the coke controlled catalyst is about <NUM> wt%; a coke content in the spent catalyst is about <NUM> wt%; process operating conditions of the reaction zone I of the coke control reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; process operating conditions of the reaction zone II of the methanol conversion reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; process operating conditions of the spent catalyst zone of the methanol conversion reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; and process operating conditions of the regenerator <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, regeneration temperature: about <NUM>, regeneration pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>.

In this example, the coke control raw material is a mixture of <NUM> wt% of hexane, <NUM> wt% of hexene, <NUM> wt% of methanol, <NUM> wt% of ethanol, and <NUM> wt% of water; the oxygen-containing compound is methanol; the spent catalyst zone fluidizing gas is a mixture of <NUM> wt% of nitrogen and <NUM> wt% of water vapor; the regeneration gas is a mixture of <NUM> wt% of air, <NUM> wt% of water vapor, and <NUM> wt% of nitrogen; an active component in the catalyst is an SAPO-<NUM> molecular sieve; a coke content in the regenerated catalyst is about <NUM> wt%; a coke content in the coke controlled catalyst is about <NUM> wt%, where a total mass of polymethylbenzene and polymethylnaphthalene accounts for about <NUM> wt% of a total mass of coke, a mass of coke species with a molecular weight greater than <NUM> accounts for about <NUM> wt% of a total mass of coke, and a quartile deviation of coke content distribution in the coke controlled catalyst is about <NUM> wt%; a coke content in the spent catalyst is about <NUM> wt%; process operating conditions of the reaction zone I of the coke control reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; process operating conditions of the reaction zone II of the methanol conversion reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; process operating conditions of the spent catalyst zone of the methanol conversion reactor <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, reaction temperature: about <NUM>, reaction pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>; and process operating conditions of the regenerator <NUM> are as follows: apparent gas linear velocity: about <NUM>/s, regeneration temperature: about <NUM>, regeneration pressure: about <NUM> kPa, and bed density: about <NUM>/m<NUM>.

This example is a comparative example and is different from Example <NUM> 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 reactor is nitrogen, which is an inert gas and does not change the properties of the regenerated catalyst in the coke control reactor, that is, a catalyst entering the reaction zone II of the methanol conversion reactor is the regenerated catalyst.

In this example, the product gas is composed of <NUM> wt% of ethylene, <NUM> wt% of propylene, <NUM> wt% of C<NUM>-C<NUM> hydrocarbon compounds, and <NUM> wt% of other components, where the other components include methane, ethane, propane, hydrogen, CO, CO<NUM>, and the like; and the unit consumption of production is <NUM> tons of methanol/ton of low-carbon olefins.

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 unit consumption of production.

Claim 1:
A method for on-line modification of a dimethyl ether/methanol to olefins (DMTO) catalyst using a coke control reactor;
wherein the coke control reactor is a reactor for controlling coke content, coke content distribution, and coke species in the DMTO catalyst;
wherein the coke control reactor comprises a coke control reactor shell, a reaction zone I, and a coke controlled catalyst settling zone;
the coke control reactor shell comprises an upper coke control reactor shell and a lower coke control reactor shell; the upper coke control reactor shell encloses the coke controlled catalyst settling zone;
the lower coke control reactor shell encloses the reaction zone I;
the reaction zone I communicates with the coke controlled catalyst settling zone;
a cross-sectional area at any position of the reaction zone I is less than a cross-sectional area at any position of the coke controlled catalyst settling zone;
n baffles are arranged in a vertical direction in the reaction zone I, bottoms of the n baffles are connected to a bottom of the coke control reactor, tops of the n baffles are located in the coke controlled catalyst settling zone, and the n baffles divide the reaction zone I into m reaction zone I subzones, wherein m and n are both integers; and
a catalyst circulation hole is formed in each of the baffles, such that a catalyst flows in the reaction zone I in a preset manner;
wherein the method at least comprises feeding a catalyst and a coke control raw material into the reaction zone I to allow a reaction to generate a product with a coke controlled catalyst,
wherein the catalyst flows in a preset manner through the catalyst circulation holes on the baffles;
characterized in that
the coke control raw material comprises <NUM> wt% to <NUM> wt% of hydrogen, <NUM> wt% to <NUM> wt% of methane, <NUM> wt% to <NUM> wt% of ethane, <NUM> wt% to <NUM> wt% of ethylene, <NUM> wt% to <NUM> wt% of propane, <NUM> wt% to <NUM> wt% of propylene, <NUM> wt% to <NUM> wt% of butane, <NUM> wt% to <NUM> wt% of butene, <NUM> wt% to <NUM> wt% of pentane, <NUM> wt% to <NUM> wt% of pentene, <NUM> wt% to <NUM> wt% of hexane, <NUM> wt% to <NUM> wt% of hexene, <NUM> wt% to <NUM> wt% of methanol, <NUM> wt% to <NUM> wt% of ethanol, and <NUM> wt% to <NUM> wt% of water; and
a content of the hydrocarbon compounds is greater than <NUM>%.