WO2024108510A1

WO2024108510A1 - Device and method for preparing aromatic hydrocarbons from naphtha

Info

Publication number: WO2024108510A1
Application number: PCT/CN2022/134181
Authority: WO
Inventors: 张涛; 张继明; 刘中民; 闫国春; 叶茂; 温亮; 张今令; 张延斌; 唐海龙; 林华东; 贾金明; 徐海波; 张骋; 马智超; 王贤高; 王翔; 马现刚; 樊港斌; 王静; 谢广岳
Original assignee: 中国神华煤制油化工有限公司; 中国科学院大连化学物理研究所
Priority date: 2022-11-24
Filing date: 2022-11-24
Publication date: 2024-05-30

Abstract

Disclosed in the present application are a device and method for preparing aromatic hydrocarbons from naphtha. The device comprises a fluidized bed reactor and a riser reactor, wherein the fluidized bed reactor is used for introducing a naphtha raw material and bringing same into contact with a catalyst from the riser reactor for a reaction so as to generate a BTX-containing product gas stream and a spent catalyst, the product gas stream is subjected to gas-solid separation, the separated product gas stream is conveyed to a downstream section, and separated unconverted naphtha is returned as a raw material to the fluidized bed reactor; and a portion of separated light alkanes is returned as a raw material to the riser reactor, and is further converted into components such as aromatic hydrocarbons. In the present application, by connecting the high-temperature riser reactor to the fluidized bed reactor with a relatively low temperature in series, the yield of the light alkanes is reduced, and the yield of the aromatic hydrocarbons is increased; and linear-chain and branched-chain aliphatic hydrocarbons can be efficiently converted into aromatic hydrocarbons with high selectivity, and the content of p-xylene in a xylene mixture is greater than 50 wt%.

Description

A naphtha-based aromatics device and method

Technical Field

The present application relates to a fluidized bed device and a method for using the same, belonging to the field of chemical technology, and in particular to a device and method for producing aromatics from naphtha.

Background technique

Aromatic hydrocarbons (benzene, toluene, xylene, collectively known as BTX) are important organic chemical raw materials. Among them, paraxylene (PX) is the most concerned product among aromatic hydrocarbons. It is mainly used to produce polyesters such as terephthalic acid (PTA), polyethylene terephthalate (PET), polybutylene terephthalate (PBT) and PTT (polypropylene terephthalate). In recent years, China's paraxylene production and consumption have continued to grow. In 2021, China's total PX imports will be about 13.65 million tons, with a foreign dependence of about 38%.

Naphtha catalytic reforming technology is the main technical route for producing aromatics. The composition of naphtha is very complex. It is not only the main raw material for catalytic reforming, but also the main raw material for cracking to produce ethylene. Its composition plays a vital role in the economic benefits of the device. Generally speaking, a high potential content of aromatics in the raw material and a moderate distillation range are beneficial to catalytic reforming; while a high content of straight-chain and branched aliphatic hydrocarbons and a low content of cycloalkanes and aromatics are suitable for cracking to produce ethylene. Usually, in order to make full use of naphtha resources and improve economic benefits, it is necessary to first separate the straight-chain and branched aliphatic hydrocarbons from cycloalkanes and aromatics in naphtha. The former is used as the raw material for producing ethylene, and the latter is used as the raw material for the catalytic reforming unit.

Naphtha fractions have a wide distillation range, and it is difficult to efficiently separate straight-chain and branched-chain aliphatic hydrocarbons from cycloalkanes and aromatics using general separation methods. In addition, catalytic reforming technology also has difficulty converting straight-chain and branched-chain aliphatic hydrocarbons into aromatics. Naphtha feedstocks used for catalytic reforming generally need to be distilled to remove top oils with a boiling point below 60°C, thereby increasing the potential aromatic content of the catalytic reforming feedstock. However, fractions with a boiling point above 60°C still contain a large amount of straight-chain and branched-chain aliphatic hydrocarbons that are difficult to convert into aromatics. Therefore, the highly selective conversion of straight-chain and branched-chain aliphatic hydrocarbons into aromatics has always been a hot spot and difficulty in the development of naphtha-to-aromatics technology.

Due to the limitations of thermodynamic equilibrium, p-xylene accounts for only ~24% of the xylene mixture produced by the naphtha catalytic reforming unit, and it is necessary to further increase the production of p-xylene through an isomerization-separation process. Therefore, increasing the p-xylene content in the xylene mixture is an important way to reduce the energy consumption of p-xylene production.

Summary of the invention

According to one aspect of the present application, a naphtha-based aromatics device is provided, which can prepare aromatics using naphtha with low aromatics potential as raw material, increase the content of p-xylene in mixed xylenes, and reduce production energy consumption.

The components of naphtha described in the present application include C ₄ -C ₁₂ straight-chain and branched-chain aliphatic hydrocarbons, cycloalkanes and aromatic hydrocarbons.

The aromatic hydrocarbons described in this application refer to benzene, toluene and xylene, collectively referred to as BTX.

The naphtha-to-aromatics device comprises a fluidized bed reactor and a riser reactor; wherein the outlet of the riser reactor is connected to the fluidized bed reactor;

The fluidized bed reactor is used to introduce naphtha raw material, which contacts with the catalyst from the riser reactor to react and generate a product gas flow containing BTX and a catalyst to be produced. The product gas flow is subjected to gas-solid separation and the separated product gas flow is sent to a downstream section. The unconverted naphtha after separation is returned to the fluidized bed reactor as a raw material; and part of the separated low-carbon alkanes are returned to the riser reactor as a raw material.

Preferably, the riser reactor is used to introduce riser reactor raw materials and catalysts to react to generate aromatics, and a flow containing unreacted riser reactor raw materials, aromatics and catalysts is passed through the outlet of the riser reactor into a fluidized bed reactor.

Preferably, the feedstock comprises water vapor and light alkanes separated from the product gas stream.

Preferably, the water vapor content in the riser reactor feed is 0-50 wt%.

Preferably, the inlet of the riser reactor is connected to a fluidized bed regenerator, and the catalyst introduced into the riser reactor is a regenerated catalyst generated by the fluidized bed regenerator.

Preferably, the fluidized bed regenerator is connected to the inlet of the riser reactor through a pipeline via a regenerator stripper and a regeneration slide valve in sequence.

Preferably, the inlet of the regenerator stripper extends into the regenerator shell of the fluidized bed regenerator and is located above the regenerator distributor.

Preferably, the fluidized bed reactor includes a reactor shell, and the area enclosed by the reactor shell is divided from top to bottom into a first gas-solid separation zone and a reaction zone, wherein the first gas-solid separation zone is provided with a gas-solid separation device and a reactor gas collecting chamber; the reactor gas collecting chamber is located at the inner top of the reactor shell, and its inlet is connected to the gas outlet of the reactor gas-solid separation device, and its outlet is connected to the product gas conveying pipe; a reactor distributor is provided at the lower part of the reaction zone for introducing naphtha raw material.

Preferably, the reactor gas-solid separation equipment 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.

Preferably, the device further comprises a fluidized bed regenerator connected to the fluidized bed reactor, wherein the fluidized bed regenerator is used to introduce regeneration gas to convert the catalyst to be regenerated into a regenerated catalyst.

Preferably, the fluidized bed reactor is connected to the fluidized bed regenerator in sequence through a reactor stripper, a regenerated sliding valve, and a regenerated agent delivery pipe; wherein the inlet of the reactor stripper extends into the reactor shell of the fluidized bed reactor and is located below the catalyst outlet end of the reactor gas-solid separation equipment.

Preferably, the fluidized bed regenerator includes a regenerator shell, and the shell enclosed by the regenerator shell is divided into a second gas-solid separation zone and a regeneration zone from top to bottom; the second gas-solid separation zone is provided with a regenerator gas-solid separation device and a regenerator gas collecting chamber; the regenerator gas collecting chamber is located at the inner top of the regenerator shell, and is provided with a flue gas conveying pipe; the gas outlet of the regenerator gas-solid separation device is connected to the regenerator gas collecting chamber; a regenerator distributor is provided in the inner lower part of the regeneration zone for introducing regeneration gas.

Preferably, the regenerator gas-solid separation equipment 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.

According to another aspect of the present application, a method for preparing aromatics from naphtha is provided, the method comprising: preparing aromatics using the above-mentioned naphtha-to-aromatics device and catalyst.

Preferably, the catalyst is a metal molecular sieve bifunctional catalyst.

Preferably, the metal molecular sieve bifunctional catalyst adopts metal-modified HZSM-5 zeolite molecular sieve;

The metal used for metal modification is selected from at least one of La, Zn, Ga, Fe, Mo and Cr;

The metal modification method comprises: placing the HZSM-5 zeolite molecular sieve in a metal salt solution, impregnating, drying and calcining to obtain the metal modified HZSM-5 zeolite molecular sieve.

Further, the method comprises: naphtha enters the reaction zone of the fluidized bed reactor through a reactor distributor, contacts with the catalyst from the riser reactor, generates a product gas stream containing BTX, light olefins, hydrogen, light alkanes, combustible gas, heavy aromatics and unconverted naphtha, and at the same time, the catalyst is coked and converted into a spent catalyst;

The product gas flow enters the gas-solid separation device of the reactor to remove the catalyst to be produced therein, and then enters the gas collecting chamber of the reactor, and enters the downstream section through the product gas delivery pipe.

Preferably, the unconverted naphtha after separation is returned to the fluidized bed reactor as a feedstock.

Preferably, part of the separated light alkanes are returned to the riser reactor as feedstock.

Preferably, the BTX refers to benzene, toluene and xylene;

The light olefins refer to ethylene and propylene;

The light alkanes are ethane and propane;

The combustible gas includes methane and CO, etc.;

The heavy aromatic hydrocarbons refer to aromatic hydrocarbons having 9 or more carbon atoms in the molecule.

Preferably, the naphtha is selected from at least one of coal direct liquefaction naphtha, coal indirect liquefaction naphtha, straight-run naphtha and hydrocracked naphtha.

Preferably, the naphtha further comprises unconverted naphtha separated from the product gas stream, and the main components of the unconverted naphtha are C ₄ -C ₁₂ straight-chain and branched-chain aliphatic hydrocarbons and cycloalkanes.

Preferably, the carbon content in the spent catalyst is 1.0-3.0 wt%.

Preferably, the process conditions of the reaction zone are: gas superficial velocity of 0.5-2.0 m/s, reaction temperature of 500-650° C., reaction pressure of 100-500 kPa, and bed density of 150-700 kg/m ³ .

Optionally, the gas superficial velocity in the reaction zone is independently selected from any value among 0.5m/s, 0.6m/s, 0.7m/s, 0.8m/s, 0.9m/s, 1.0m/s, 1.1m/s, 1.2m/s, 1.3m/s, 1.4m/s, 1.5m/s, 1.6m/s, 1.7m/s, 1.8m/s, 1.9m/s, 2.0m/s or any range between two of them.

Optionally, the reaction temperature of the reaction zone is independently selected from any value of 500°C, 510°C, 520°C, 530°C, 540°C, 550°C, 560°C, 570°C, 580°C, 590°C, 600°C, 610°C, 620°C, 630°C, 640°C, 650°C or any range therebetween.

Optionally, the reaction pressure of the reaction zone is independently selected from any value among 100 kPa, 125 kPa, 150 kPa, 175 kPa, 200 kPa, 225 kPa, 250 kPa, 275 kPa, 300 kPa, 325 kPa, 350 kPa, 375 kPa, 400 kPa, 425 kPa, 450 kPa, 475 kPa, 500 kPa, or any range value between two of them.

Optionally, the bed density of the reaction zone is independently selected from any value of 150kg/ ^m3 , ^200kg / ^m3 , 250kg/m3, 300kg/ ^m3 , 350kg/ ^m3 , 400kg/ ^m3 , ^450kg /m3, 500kg/ ^m3 , 550kg/ ^m3 , 600kg/ ^m3 , 650kg/ ^m3 , 700kg/ ^m3 or any range therebetween.

Preferably, the method further comprises: introducing a riser reactor raw material and a catalyst into the riser reactor to react and generate aromatics;

A stream comprising unreacted riser reactor feedstock, aromatic hydrocarbons and catalyst is passed from the riser reactor outlet into the fluidized bed reactor.

Preferably, the catalyst is a regenerated catalyst from a fluidized bed regenerator.

Preferably, the regenerated catalyst enters the riser reactor through the regenerator stripper and the regeneration slide valve in sequence.

Preferably, the carbon content in the regenerated catalyst is ≤0.5 wt%.

Preferably, the riser reactor feed comprises water vapor and light alkanes separated from the product gas stream.

Preferably, the water vapor content in the riser reactor feed is 0-50 wt%.

Preferably, the process conditions of the riser reactor are: gas superficial velocity of 3.0-10.0 m/s, temperature of 580-700° C., pressure of 100-500 kPa, and bed density of 50-150 kg/m ³ .

Optionally, the gas superficial velocity is independently selected from any value among 3.0m/s, 3.5m/s, 4.0m/s, 4.5m/s, 5.0m/s, 5.5m/s, 6.0m/s, 6.5m/s, 7.0m/s, 7.5m/s, 8.0m/s, 8.5m/s, 9.0m/s, 9.5m/s, 10.0m/s or any range between two values.

Optionally, the temperature is independently selected from any value of 580°C, 590°C, 600°C, 610°C, 620°C, 630°C, 640°C, 650°C, 660°C, 670°C, 680°C, 690°C, 700°C or any range therebetween.

Optionally, the pressure is independently selected from any value of 100 kPa, 125 kPa, 150 kPa, 175 kPa, 200 kPa, 225 kPa, 250 kPa, 275 kPa, 300 kPa, 325 kPa, 350 kPa, 375 kPa, 400 kPa, 425 kPa, 450 kPa, 475 kPa, 500 kPa, or any range between two of them.

Optionally, the bed density is independently selected from any value of 50kg/ ^m3 , 60kg/ ^m3 , 70kg/ ^m3 , 80kg/ ^m3 , 90kg/ ^m3 , 100kg/ ^m3 , 110kg/ ^m3 , 120kg/ ^m3 , 130kg/ ^m3 , 140kg/ ^m3 , 150kg/ ^m3 or any range therebetween.

Preferably, the method further comprises: the catalyst to be regenerated enters the reactor stripper from the open end of the reactor stripper inlet pipe, and after being stripped by the reactor stripper, passes through the slide valve to be regenerated and the catalyst to be regenerated conveying pipe and enters the downstream area.

Preferably, the downstream zone is a fluidized bed regenerator.

Preferably, the regeneration gas is introduced into the regeneration zone of the fluidized bed regenerator through the regenerator distributor, and contacts the catalyst to be regenerated from the fluidized bed reactor. The coke on the catalyst to be regenerated reacts with the regeneration gas to generate flue gas. At the same time, the catalyst to be regenerated is converted into a regenerated catalyst.

Preferably, the catalyst to be regenerated sequentially passes through the reactor stripper, the slide valve to be regenerated and the regenerated catalyst delivery pipe into the fluidized bed regenerator, contacts and reacts with the regeneration gas to obtain flue gas and regenerated catalyst;

The flue gas enters the gas-solid separation device of the regenerator to remove the regenerated catalyst carried therein, and then enters the gas collecting chamber of the regenerator and enters the downstream section through the flue gas conveying pipe.

Preferably, the regeneration gas is selected from at least one of oxygen, air and oxygen-enriched air.

Optionally, the process conditions of the regeneration zone are: gas superficial linear velocity of 0.5-2.0 m/s, regeneration temperature of 600-750° C., regeneration pressure of 100-500 kPa, and bed density of 150-700 kg/m ³ .

Optionally, the gas superficial velocity is independently selected from any value among 0.5m/s, 0.6m/s, 0.7m/s, 0.8m/s, 0.9m/s, 1.0m/s, 1.1m/s, 1.2m/s, 1.3m/s, 1.4m/s, 1.5m/s, 1.6m/s, 1.7m/s, 1.8m/s, 1.9m/s, 2.0m/s or any range between two values.

Optionally, the regeneration temperature is independently selected from any value of 600°C, 615°C, 630°C, 645°C, 660°C, 675°C, 690°C, 705°C, 720°C, 735°C, 750°C or any range therebetween.

Optionally, the regeneration pressure is independently selected from any value of 100 kPa, 125 kPa, 150 kPa, 175 kPa, 200 kPa, 225 kPa, 250 kPa, 275 kPa, 300 kPa, 325 kPa, 350 kPa, 375 kPa, 400 kPa, 425 kPa, 450 kPa, 475 kPa, 500 kPa, or any range between two of them.

Optionally, the bed density is independently selected from any value of 150kg/ ^m3 , 200kg/ ^m3 , 250kg/ ^m3 , 300kg/m3, 350kg/ ^m3 ^, 400kg/ ^m3 , 450kg/ ^m3 , 500kg/ ^m3 , 550kg/ ^m3 , 600kg/ ^m3 , 650kg/ ^m3 , 700kg/ ^m3 or any range therebetween.

In the present application, the potential aromatic content of naphtha raw material is 0-80wt%, and the single-pass conversion rate of naphtha is 70-95wt%. Using the naphtha aromatics device and the naphtha aromatics method based on the device of the present application, the final product distribution is: 60-75wt% BTX, 7-15wt% light olefins, 3-8wt% hydrogen, 2-7wt% light alkanes, 4-6wt% combustible gas, 3-7wt% heavy aromatics, 0.5-1wt% coke. The p-xylene content in the mixed xylene in the product is 50-65wt%.

The beneficial effects of this application include:

1) The present invention can efficiently and selectively convert straight-chain and branched aliphatic hydrocarbons into aromatic hydrocarbons, and has a wide range of raw material adaptability, and can use naphtha with low aromatic hydrocarbon potential content as a raw material to prepare aromatic hydrocarbons.

2) The present application realizes aromatization of low-carbon alkanes through a riser reactor and a metal molecular sieve bifunctional catalyst, greatly improving the aromatics yield of naphtha-to-aromatics technology.

3) The aromatic product produced by the present application has a p-xylene content in the xylene mixture of >50wt%, which is much higher than the thermodynamic equilibrium content (about 24wt%), which can effectively increase the p-xylene yield and significantly reduce the energy consumption for separating p-xylene.

4) The naphtha aromatics device of the present application includes a fluidized bed reactor and a riser reactor. Since low-carbon alkanes are very stable and require a higher reaction temperature, in the naphtha aromatics device of the present application, the high-temperature regenerated catalyst first enters the riser reactor and contacts with low-carbon alkanes, and the low-carbon alkanes undergo aromatization reaction under the action of the catalyst, thereby increasing the yield of aromatics; then, the catalyst with the lowered temperature is passed into the fluidized bed reactor and contacts with naphtha, thereby eliminating the local high-temperature zone in the fluidized bed reactor, effectively reducing the yield of low-carbon alkanes and increasing the yield of aromatics. The naphtha aromatics device of the present application achieves the beneficial effects of reducing the yield of low-carbon alkanes and increasing the yield of aromatics by connecting a high-temperature riser reactor and a relatively low-temperature fluidized bed reactor in series.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a naphtha-to-aromatics unit in one embodiment of the present application.

List of parts and reference numerals:

1: fluidized bed reactor; 1-1: reactor shell; 1-2: reactor distributor; 1-3: reactor gas-solid separation equipment; 1-4: reactor gas collecting chamber; 1-5: product gas delivery pipe; 1-6: reactor stripper; 1-7: slide valve to be generated; 1-8: generated agent delivery pipe;

2: fluidized bed regenerator; 2-1: regenerator shell; 2-2: regenerator distributor; 2-3: regenerator gas-solid separation equipment; 2-4: regenerator gas collecting chamber; 2-5: flue gas conveying pipe; 2-6: regenerator stripper; 2-7: regeneration slide valve;

3: Riser reactor.

Detailed ways

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

The present application provides a naphtha-to-aromatics device, comprising a fluidized bed reactor and a riser reactor; wherein the outlet of the riser reactor is connected to the fluidized bed reactor;

The BTX refers to benzene, toluene and xylene.

In one embodiment, the light olefins refer to ethylene and propylene.

The light alkanes are ethane and propane.

The combustible gas includes methane, CO and the like.

In one embodiment, the naphtha is selected from at least one of coal direct liquefaction naphtha, coal indirect liquefaction naphtha, straight run naphtha and hydrocracked naphtha.

In one embodiment, the naphtha further comprises unconverted naphtha separated from the product gas stream, and the main components of the unconverted naphtha are C ₄ -C ₁₂ straight-chain and branched-chain aliphatic hydrocarbons and cycloalkanes.

In one embodiment, the riser reactor feed comprises water vapor and light alkanes separated from the product gas stream.

In one embodiment, the water vapor content in the riser reactor feed is 0-50 wt%.

In one embodiment, the inlet of the riser reactor is connected to a fluidized bed regenerator, and the catalyst introduced into the riser reactor is a regenerated catalyst generated by the fluidized bed regenerator.

In one embodiment, the fluidized bed regenerator is connected to the inlet of the riser reactor through a pipeline via a regenerator stripper and a regeneration slide valve.

In one embodiment, the inlet of the regenerator stripper extends into the regenerator shell of the fluidized bed regenerator and is located above the regenerator distributor.

In one embodiment, the riser reactor is used to introduce riser reactor feedstock and catalyst to react to generate aromatics, and a flow containing unreacted riser reactor feedstock, aromatics and catalyst is passed through the outlet of the riser reactor into a fluidized bed reactor.

Furthermore, the fluidized bed reactor includes a reactor shell, and the area enclosed by the reactor shell is divided from top to bottom into a first gas-solid separation zone and a reaction zone, and the first gas-solid separation zone is provided with a gas-solid separation device and a reactor gas collecting chamber; the reactor gas collecting chamber is located at the inner top of the reactor shell, and its inlet is connected to the gas outlet of the reactor gas-solid separation device, and its outlet is connected to the product gas conveying pipe; a reactor distributor is provided at the lower part of the reaction zone for introducing naphtha raw material.

In one embodiment, the reactor gas-solid separation equipment 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.

In a preferred embodiment, the device further comprises a fluidized bed regenerator connected to the fluidized bed reactor, and the fluidized bed regenerator is used to introduce regeneration gas to convert the catalyst to be regenerated into a regenerated catalyst. Referring to FIG1 , the device comprises a fluidized bed reactor 1, a fluidized bed regenerator 2 and a riser reactor 3.

The fluidized bed reactor 1 comprises: a reactor shell 1-1, a reactor distributor 1-2, a reactor gas-solid separation device 1-3, a reactor gas collecting chamber 1-4, a product gas conveying pipe 1-5, a reactor stripper 1-6, a slide valve to be generated 1-7, and a conveying pipe for a generated agent 1-8.

The reactor shell 1-1 comprises an upper reactor shell and a lower reactor shell, wherein the upper reactor shell encloses a first gas-solid separation zone, and the lower reactor shell encloses a reaction zone; an outlet of a riser reactor 3 is provided on the reactor shell 1-1.

A reactor distributor 1-2 is provided at the lower part of the reaction zone, and the reactor distributor 1-2 is used for introducing naphtha raw material.

The reactor shell 1-1 is also provided with a reactor gas-solid separation device 1-3 and a reactor gas collecting chamber 1-4; the reactor gas collecting chamber 1-4 is located at the inner top of the reactor shell; the gas outlet of the reactor gas-solid separation device 1-3 is connected to the reactor gas collecting chamber 1-4; the reactor gas collecting chamber 1-4 is connected to the product gas conveying pipe 1-5; the catalyst outlet end of the reactor gas-solid separation device 1-3 is located above the opening end of the inlet pipe of the reactor stripper 1-6.

A reactor stripper 1-6 is provided below the reaction zone; the inlet of the reactor stripper 1-6 is located inside the reactor shell 1-1; the outlet of the reactor stripper 1-6 is located outside the reactor shell 1-1 and is connected to a slide valve 1-7 to be generated; the open end of the inlet of the reactor stripper 1-6 is located above the reactor distributor 1-2.

A slide valve 1-7 is provided below the reactor stripper 1-6; the inlet of the slide valve 1-7 is connected to the outlet of the reactor stripper 1-6, the outlet of the slide valve 1-7 is connected to the inlet of the spent agent delivery pipe 1-8, and the outlet of the spent agent delivery pipe 1-8 is connected to the regenerator shell 2-1.

The slide valve 1-7 to be regenerated is used to control the circulation amount of the catalyst to be regenerated.

In a preferred embodiment, the reactor gas-solid separation equipment 1-3 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.

The fluidized bed regenerator 2 comprises: a regenerator shell 2-1, a regenerator distributor 2-2, a regenerator gas-solid separation device 2-3, a regenerator gas collecting chamber 2-4, a flue gas conveying pipe 2-5, a regenerator stripper 2-6, and a regeneration slide valve 2-7.

The regenerator shell 2-1 comprises an upper shell and a lower shell. The upper shell forms a second gas-solid separation zone, and the lower shell forms a regeneration zone. The regenerator shell 2-1 is provided with an outlet of a regenerated agent delivery pipe 1-8.

A regenerator distributor 2-2 is provided at the lower part of the regeneration zone, and the regenerator distributor 2-2 is used for introducing the regeneration gas.

The regenerator shell 2-1 is also provided with a regenerator gas-solid separation device 2-3 and a regenerator gas collecting chamber 2-4; the regenerator gas collecting chamber 2-4 is located at the inner top of the regenerator shell 2-1; the gas outlet of the regenerator gas-solid separation device 2-3 is connected to the regenerator gas collecting chamber 2-4; the regenerator gas collecting chamber 2-4 is connected to the flue gas conveying pipe 2-5; the catalyst outlet end of the regenerator gas-solid separation device 2-3 is located above the opening end of the inlet pipe of the regenerator stripper 2-6.

A regenerator stripper 2-6 is provided below the regeneration zone; the inlet of the regenerator stripper 2-6 is located inside the regenerator shell 2-1; the outlet of the regenerator stripper 2-6 is located outside the regenerator shell 2-1 and is connected to the regeneration slide valve 2-7; the opening end of the inlet of the regenerator stripper 2-6 is located above the regenerator distributor 2-2.

A regeneration slide valve 2-7 is provided below the regenerator stripper 2-6; the inlet of the regeneration slide valve 2-7 is connected to the outlet of the regenerator stripper 2-6.

The regeneration slide valve 2-7 is used to control the circulation amount of the regenerated catalyst.

In a preferred embodiment, the regenerator gas-solid separation equipment 2-3 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.

The inlet of the riser reactor 3 is connected to the regeneration slide valve 2-7, and the outlet of the riser reactor 3 is connected to the reactor shell 1-1.

In order to achieve aromatization of straight-chain and branched aliphatic hydrocarbons, increase the yield of aromatics and the content of p-xylene in mixed xylenes, the present application provides a method for preparing aromatics from naphtha, comprising: preparing aromatics using the above-mentioned naphtha aromatics device and catalyst.

In one embodiment, the catalyst is a metal molecular sieve bifunctional catalyst.

In a preferred embodiment, the metal molecular sieve bifunctional catalyst uses a metal-modified HZSM-5 zeolite molecular sieve;

The metal used for metal modification is selected from at least one of La, Zn, Ga, Fe, Mo, and Cr;

The metal modification method comprises: placing the HZSM-5 zeolite molecular sieve in a metal salt solution, impregnating, drying, and calcining to obtain the metal modified HZSM-5 zeolite molecular sieve. The following Examples 1-5 all use the metal modified HZSM-5 zeolite molecular sieve.

In a preferred embodiment, the method comprises the following steps:

a) Naphtha enters the reaction zone of the fluidized bed reactor 1 through the reactor distributor 1-2, and contacts the catalyst from the riser reactor 3 to generate a product gas stream containing BTX, light olefins, hydrogen, light alkanes, combustible gas, heavy aromatics and unconverted naphtha. At the same time, the catalyst is coked and converted into a catalyst to be regenerated. The product gas stream enters the reactor gas-solid separation device 1-3 to remove the catalyst to be regenerated, and then enters the reactor gas collection chamber 1-4, and enters the downstream section through the product gas delivery pipe 1-5. The catalyst to be regenerated in the reaction zone enters the reactor stripper 1-6 from the open end of the inlet pipe of the reactor stripper 1-6, and is stripped. After stripping, it passes through the slide valve 1-7 to be regenerated and the delivery pipe 1-8 to be regenerated into the fluidized bed regenerator 2.

b) The regeneration gas is introduced into the regeneration zone of the fluidized bed regenerator 2 through the regenerator distributor 2-2, and contacts with the catalyst to be regenerated. The coke on the catalyst to be regenerated reacts with the regeneration gas to generate flue gas. At the same time, the catalyst to be regenerated is converted into a regenerated catalyst. The flue gas enters the regenerator gas-solid separation device 2-3 to remove the regenerated catalyst carried therein, and then enters the regenerator gas collection chamber 2-4, and enters the downstream section through the flue gas conveying pipe 2-5. The regenerated catalyst enters the riser reactor 3 through the regenerator stripper 2-6 and the regeneration slide valve 2-7 in sequence.

c) The riser reactor feedstock is introduced into the riser reactor 3, where it contacts and reacts with the regenerated catalyst from the fluidized bed regenerator 2, and the riser reactor feedstock is converted into aromatic hydrocarbons under the action of the catalyst. Then, a stream containing unreacted riser reactor feedstock, aromatic hydrocarbons and catalyst enters the fluidized bed reactor 1 from the outlet of the riser reactor 3.

The light olefins refer to ethylene and propylene.

The light alkanes are ethane and propane.

The combustible gas includes methane, CO and the like.

In a preferred embodiment, the naphtha is selected from at least one of coal direct liquefaction naphtha, coal indirect liquefaction naphtha, straight run naphtha and hydrocracked naphtha.

In a preferred embodiment, the naphtha further comprises unconverted naphtha separated from the product gas stream.

In a preferred embodiment, the carbon content in the spent catalyst is 1.0-3.0 wt%.

In a preferred embodiment, the process conditions of the reaction zone are: gas superficial velocity of 0.5-2.0 m/s, reaction temperature of 500-650° C., reaction pressure of 100-500 kPa, and bed density of 150-700 kg/m ³ .

Optionally, the reaction temperature of the reaction zone is independently selected from any value among 500°C, 510°C, 520°C, 530°C, 540°C, 550°C, 560°C, 570°C, 580°C, 590°C, 600°C, 610°C, 620°C, 630°C, 640°C, 650°C or any range between two of them.

In a preferred embodiment, the carbon content in the regenerated catalyst is ≤0.5 wt%.

In a preferred embodiment, the regeneration gas is selected from at least one of oxygen, air and oxygen-enriched air.

In a preferred embodiment, the process conditions of the regeneration zone are: gas superficial linear velocity of 0.5-2.0 m/s, regeneration temperature of 600-750° C., regeneration pressure of 100-500 kPa, and bed density of 150-700 kg/m ³ .

Optionally, the regeneration temperature is independently selected from any value of 600°C, 615°C, 630°C, 645°C, 660°C, 675°C, 690°C, 705°C, 720°C, 735°C, 750°C, or any range therebetween.

In a preferred embodiment, the riser reactor feedstock comprises water vapor and light alkanes separated from the product gas stream.

In a preferred embodiment, the water vapor content in the riser reactor feed is 0-50 wt%.

In a preferred embodiment, the process conditions of the riser reactor are: gas superficial velocity of 3.0-10.0 m/s, temperature of 580-700° C., pressure of 100-500 kPa, and bed density of 50-150 kg/m ³ .

Optionally, the temperature is independently selected from any value of 580°C, 590°C, 600°C, 610°C, 620°C, 630°C, 640°C, 650°C, 660°C, 670°C, 680°C, 690°C, 700°C, or any range therebetween.

In the embodiment described in the present application, the aromatics potential content of the naphtha feedstock is 0-80wt%, the single-pass conversion rate of the naphtha is 70-95wt%, the unconverted naphtha is separated from the product gas and returned to the fluidized bed reactor as a raw material, and some low-carbon alkanes are separated from the product gas and returned to the riser reactor as a raw material, and the final product distribution is: 60-75wt% BTX, 7-15wt% low-carbon olefins, 3-8wt% hydrogen, 2-7wt% low-carbon alkanes, 4-6wt% combustible gas, 3-7wt% heavy aromatics, 0.5-1wt% coke. The p-xylene content in the mixed xylene in the product is 50-65wt%.

Example 1

This embodiment adopts the device shown in Figure 1.

In this embodiment, the naphtha feedstock entering the fluidized bed reactor is coal direct liquefaction naphtha, whose aromatics potential content is 78wt%. The naphtha feedstock entering the fluidized bed reactor also includes unconverted naphtha separated from the product gas flow.

The process conditions of the reaction zone of the fluidized bed reactor are: gas superficial linear velocity of 0.5 m/s, reaction temperature of 645° C., reaction pressure of 100 kPa, and bed density of 700 kg/m ³ .

The regeneration gas is air.

The process conditions of the regeneration zone of the fluidized bed regenerator are: gas superficial linear velocity of 0.5 m/s, regeneration temperature of 745°C, regeneration pressure of 100 kPa, and bed density of 700 kg/m ³ .

The raw material of the riser reactor is the light alkane separated from the product gas stream.

The process conditions of the riser reactor are: gas superficial velocity of 3.0 m/s, temperature of 690° C., pressure of 100 kPa, and bed density of 150 kg/m ³ .

The carbon content in the spent catalyst is 1.1 wt %, and the carbon content in the regenerated catalyst is 0.1 wt %.

The single-pass conversion of the naphtha feedstock entering the fluidized bed reactor was 71 wt%.

The product distribution is: 74.5wt% BTX, 7wt% light olefins, 3wt% hydrogen, 2wt% light alkanes, 6wt% combustible gas, 7wt% heavy aromatics, 0.5wt% coke. The content of p-xylene in the mixed xylene in the product is 51wt%.

Example 2

This embodiment adopts the device shown in Figure 1.

In this embodiment, the naphtha feedstock entering the fluidized bed reactor is coal indirect liquefaction naphtha, whose aromatics potential content is 0.1wt%. The naphtha feedstock entering the fluidized bed reactor also includes unconverted naphtha separated from the product gas flow.

The process conditions of the reaction zone of the fluidized bed reactor are: gas superficial linear velocity of 2.0 m/s, reaction temperature of 510° C., reaction pressure of 500 kPa, and bed density of 150 kg/m ³ .

The regeneration gas is oxygen.

The process conditions of the regeneration zone of the fluidized bed regenerator are: gas superficial linear velocity of 2.0 m/s, regeneration temperature of 610° C., regeneration pressure of 500 kPa, and bed density of 150 kg/m ³ .

The feedstock of the riser reactor comprises water vapor and light alkanes separated from the product gas stream, wherein the water vapor content is 50 wt%.

The process conditions of the riser reactor are: gas superficial velocity of 10.0 m/s, temperature of 580° C., pressure of 500 kPa, and bed density of 50 kg/m ³ .

The carbon content in the spent catalyst is 2.8 wt %, and the carbon content in the regenerated catalyst is 0.3 wt %.

The single-pass conversion of the naphtha feedstock entering the fluidized bed reactor was 75 wt%.

The product distribution is: 66wt% BTX, 12wt% light olefins, 7wt% hydrogen, 3wt% light alkanes, 5wt% combustible gas, 6wt% heavy aromatics, 1.0wt% coke. The content of p-xylene in the mixed xylene in the product is 61wt%.

Example 3

This embodiment adopts the device shown in Figure 1.

In this embodiment, the naphtha feedstock entering the fluidized bed reactor is coal indirect liquefaction naphtha, whose aromatics potential content is 3wt%. The naphtha feedstock entering the fluidized bed reactor also includes unconverted naphtha separated from the product gas stream.

The process conditions of the reaction zone of the fluidized bed reactor are: gas superficial linear velocity of 1.2 m/s, reaction temperature of 550° C., reaction pressure of 120 kPa, and bed density of 260 kg/m ³ .

The regeneration gas is oxygen-enriched air.

The process conditions of the regeneration zone of the fluidized bed regenerator are: gas superficial linear velocity of 1.2 m/s, regeneration temperature of 650° C., regeneration pressure of 120 kPa, and bed density of 260 kg/m ³ .

The feedstock of the riser reactor comprises water vapor and light alkanes separated from the product gas stream, wherein the water vapor content is 25 wt %.

The process conditions of the riser reactor are: gas superficial velocity of 7.0 m/s, temperature of 630° C., pressure of 120 kPa, and bed density of 80 kg/m ³ .

The carbon content in the spent catalyst is 2.1 wt %, and the carbon content in the regenerated catalyst is 0.2 wt %.

The single-pass conversion of the naphtha feedstock entering the fluidized bed reactor was 95 wt%.

The product distribution is: 61wt% BTX, 15wt% light olefins, 8wt% hydrogen, 7wt% light alkanes, 5.2wt% combustible gas, 3wt% heavy aromatics, 0.8wt% coke. The content of p-xylene in the mixed xylene in the product is 65wt%.

Example 4

This embodiment adopts the device shown in Figure 1.

In this embodiment, the naphtha feedstock entering the fluidized bed reactor is straight-run naphtha with a latent aromatic content of 46 wt %. The naphtha feedstock entering the fluidized bed reactor also includes unconverted naphtha separated from the product gas stream.

The process conditions of the reaction zone of the fluidized bed reactor are: gas superficial linear velocity of 1.8 m/s, reaction temperature of 600° C., reaction pressure of 200 kPa, and bed density of 220 kg/m ³ .

The regeneration gas is air.

The process conditions of the regeneration zone of the fluidized bed regenerator are: gas superficial linear velocity of 1.8 m/s, regeneration temperature of 700° C., regeneration pressure of 200 kPa, and bed density of 220 kg/m ³ .

The process conditions of the riser reactor are: gas superficial velocity of 5.0 m/s, temperature of 660° C., pressure of 200 kPa, and bed density of 110 kg/m ³ .

The carbon content in the spent catalyst is 1.5 wt %, and the carbon content in the regenerated catalyst is 0.1 wt %.

The single-pass conversion of the naphtha feedstock entering the fluidized bed reactor was 86 wt%.

The product distribution is: 68wt% BTX, 10wt% light olefins, 6wt% hydrogen, 5wt% light alkanes, 4wt% combustible gas, 6wt% heavy aromatics, 1.0wt% coke. The content of p-xylene in the mixed xylene in the product is 63wt%.

Example 5

This embodiment adopts the device shown in Figure 1.

In this embodiment, the naphtha feedstock entering the fluidized bed reactor is hydrocracked naphtha, whose aromatics potential content is 64 wt %. The naphtha feedstock entering the fluidized bed reactor also includes unconverted naphtha separated from the product gas stream.

The process conditions of the reaction zone of the fluidized bed reactor are: gas superficial linear velocity of 1.0 m/s, reaction temperature of 580° C., reaction pressure of 150 kPa, and bed density of 350 kg/m ³ .

The regeneration gas is air.

The process conditions of the regeneration zone of the fluidized bed regenerator are: gas superficial linear velocity of 1.0 m/s, regeneration temperature of 680° C., regeneration pressure of 150 kPa, and bed density of 350 kg/m ³ .

The feedstock of the riser reactor comprises water vapor and light alkanes separated from the product gas stream, wherein the water vapor content is 40 wt%.

The process conditions of the riser reactor are: gas superficial velocity of 7.0 m/s, temperature of 650° C., pressure of 150 kPa, and bed density of 80 kg/m ³ .

The carbon content in the spent catalyst is 1.4 wt %, and the carbon content in the regenerated catalyst is 0.5 wt %.

The single-pass conversion of the naphtha feedstock entering the fluidized bed reactor was 77 wt%.

The product distribution is: 71.3wt% BTX, 9wt% light olefins, 5wt% hydrogen, 2wt% light alkanes, 6wt% combustible gas, 6wt% heavy aromatics, 0.7wt% coke. The content of p-xylene in the mixed xylene in the product is 58wt%.

The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the above disclosed technical content to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

A naphtha-to-aromatics device, characterized in that the device comprises a fluidized bed reactor and a riser reactor; wherein the outlet of the riser reactor is connected to the fluidized bed reactor;

The fluidized bed reactor is used to introduce naphtha raw material, which contacts with the catalyst from the riser reactor to react and generate a product gas flow containing BTX and a catalyst to be produced. The product gas flow is subjected to gas-solid separation and the separated product gas flow is sent to a downstream section. The unconverted naphtha after separation is returned to the fluidized bed reactor as a raw material; and part of the separated low-carbon alkanes are returned to the riser reactor as a raw material.
The naphtha to aromatics device according to claim 1 is characterized in that the riser reactor is used to introduce a riser reactor raw material and a catalyst to react to generate aromatics, and a logistics containing unreacted riser reactor raw material, aromatics and catalyst is passed through the outlet of the riser reactor into the fluidized bed reactor.
The naphtha to aromatics device according to claim 2, characterized in that the riser reactor feedstock comprises water vapor and light alkanes separated from the product gas stream.
The naphtha to aromatics device according to claim 2 or 3, characterized in that the water vapor content in the raw material of the riser reactor is 0-50wt%.
The naphtha to aromatics device according to claim 1 is characterized in that the inlet of the riser reactor is connected to the fluidized bed regenerator, and the catalyst introduced into the riser reactor is the regenerated catalyst generated by the fluidized bed regenerator.
The naphtha to aromatics device according to claim 5, characterized in that the fluidized bed regenerator is connected to the inlet of the riser reactor through a pipeline in sequence via a regenerator stripper and a regeneration slide valve.
The naphtha to aromatics device according to claim 6, characterized in that the inlet of the regenerator stripper extends into the regenerator shell of the fluidized bed regenerator and is located above the regenerator distributor.
The naphtha to aromatics device according to claim 1 is characterized in that the fluidized bed reactor comprises a reactor shell, and the area enclosed by the reactor shell is divided from top to bottom into a first gas-solid separation zone and a reaction zone, and the first gas-solid separation zone is provided with a gas-solid separation device and a reactor gas collecting chamber; the reactor gas collecting chamber is located at the inner top of the reactor shell, and its inlet is connected to the gas outlet of the reactor gas-solid separation device, and its outlet is connected to the product gas conveying pipe; a reactor distributor is provided at the lower part of the reaction zone for introducing naphtha raw material.
According to the naphtha to aromatics device of claim 8, the reactor gas-solid separation equipment 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.
The naphtha to aromatics device according to claim 1 is characterized in that the device also includes a fluidized bed regenerator connected to the fluidized bed reactor, and the fluidized bed regenerator is used to pass regeneration gas to convert the catalyst to be regenerated into a regenerated catalyst.
The naphtha to aromatics device according to claim 1 is characterized in that the fluidized bed reactor is connected to the fluidized bed regenerator in sequence through a reactor stripper, a slide valve to be regenerated, and a regenerated agent delivery pipe; wherein the inlet of the reactor stripper extends into the reactor shell of the fluidized bed reactor and is located below the catalyst outlet end of the reactor gas-solid separation device.
The naphtha to aromatics device according to claim 1 is characterized in that the fluidized bed regenerator comprises a regenerator shell, and the shell enclosed by the regenerator shell is divided into a second gas-solid separation zone and a regeneration zone from top to bottom; the second gas-solid separation zone is provided with a regenerator gas-solid separation device and a regenerator gas collecting chamber; the regenerator gas collecting chamber is located at the inner top of the regenerator shell, and a flue gas conveying pipe is provided thereon; the gas outlet of the regenerator gas-solid separation device is connected to the regenerator gas collecting chamber; a regenerator distributor is provided at the inner lower part of the regeneration zone for introducing regeneration gas.
The naphtha-to-aromatics device according to claim 12 is characterized in that the regenerator gas-solid separation equipment 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.
A method for preparing aromatics from naphtha, characterized in that the method comprises: preparing aromatics using the naphtha-to-aromatics device and catalyst described in any one of claims 1 to 13.
The method for preparing aromatics from naphtha according to claim 14, characterized in that the catalyst is a metal molecular sieve bifunctional catalyst.
The method for preparing aromatics from naphtha according to claim 15, characterized in that the metal molecular sieve bifunctional catalyst adopts a metal-modified HZSM-5 zeolite molecular sieve;

The metal used for metal modification is selected from at least one of La, Zn, Ga, Fe, Mo, and Cr;

The metal modification method comprises: placing the HZSM-5 zeolite molecular sieve in a metal salt solution, impregnating, drying and calcining to obtain the metal modified HZSM-5 zeolite molecular sieve.
The method for preparing aromatics from naphtha according to claim 14, characterized in that the method comprises: naphtha enters the reaction zone of the fluidized bed reactor through a reactor distributor, contacts with the catalyst from the riser reactor, generates a product gas stream containing BTX, light olefins, hydrogen, light alkanes, combustible gas, heavy aromatics and unconverted naphtha, and at the same time, the catalyst is coked and converted into a catalyst to be produced;

The product gas flow enters the gas-solid separation device of the reactor to remove the catalyst to be produced therein, and then enters the gas collecting chamber of the reactor, and enters the downstream section through the product gas delivery pipe.
The method for preparing aromatics from naphtha according to claim 17, characterized in that the method further comprises: returning the separated unconverted naphtha to the fluidized bed reactor as a raw material.
The method for preparing aromatics from naphtha according to claim 17 is characterized in that the method further comprises: returning part of the separated low-carbon alkanes to the riser reactor as a raw material.
The method for preparing aromatics from naphtha according to claim 17, characterized in that the light olefins are ethylene and propylene;

The light alkanes are ethane and propane;

The combustible gas comprises methane and CO;

The heavy aromatic hydrocarbons refer to aromatic hydrocarbons having 9 or more carbon atoms in the molecule.
The method for preparing aromatics from naphtha according to claim 17, characterized in that the naphtha is selected from at least one of coal direct liquefaction naphtha, coal indirect liquefaction naphtha, straight-run naphtha and hydrocracking naphtha.
The method for preparing aromatics from naphtha according to claim 21, characterized in that the naphtha further comprises unconverted naphtha separated from the product gas stream, and the main components of the unconverted naphtha are C4 - C12 straight-chain and branched aliphatic hydrocarbons and cycloalkanes.
The method for preparing aromatics from naphtha according to claim 17, characterized in that the carbon content in the spent catalyst is 1.0-3.0wt%.
The method for preparing aromatics from naphtha according to claim 17, characterized in that the process conditions of the reaction zone are: gas superficial velocity of 0.5-2.0 m/s, reaction temperature of 500-650°C, reaction pressure of 100-500 kPa, and bed density of 150-700 kg/m 3 .
The method for preparing aromatics from naphtha according to claim 17, characterized in that the method further comprises: introducing a riser reactor raw material and a catalyst into the riser reactor to react and generate aromatics;

A stream comprising unreacted riser reactor feedstock, aromatic hydrocarbons and catalyst is passed from the riser reactor outlet into the fluidized bed reactor.
The method for producing aromatics from naphtha according to claim 25, characterized in that the catalyst is a regenerated catalyst from a fluidized bed regenerator.
The method for producing aromatics from naphtha according to claim 26, characterized in that the regenerated catalyst enters the riser reactor through the regenerator stripper and the regeneration slide valve in sequence.
The method for preparing aromatics from naphtha according to claim 26, characterized in that the carbon content in the regenerated catalyst is ≤0.5wt%.
The method for producing aromatics from naphtha according to claim 25, characterized in that the feedstock of the riser reactor comprises water vapor and light alkanes separated from the product gas stream.
The method for producing aromatics from naphtha according to claim 25, characterized in that the water vapor content in the feedstock of the riser reactor is 0-50wt%.
The method for preparing aromatics from naphtha according to claim 25, characterized in that the process conditions of the riser reactor are: gas superficial velocity of 3.0-10.0 m/s, temperature of 580-700°C, pressure of 100-500 kPa, and bed density of 50-150 kg/m 3 .
The method for preparing aromatics from naphtha according to claim 17 is characterized in that the method further comprises: the catalyst to be generated enters the reactor stripper from the open end of the reactor stripper inlet pipe, and after being stripped by the reactor stripper, passes through the slide valve to be generated and the catalyst to be generated delivery pipe to enter the downstream area.
The method for producing aromatics from naphtha according to claim 32, characterized in that the downstream area is a fluidized bed regenerator.
The method for preparing aromatics from naphtha according to claim 32 is characterized in that the method also includes: the regeneration gas is passed into the regeneration zone of the fluidized bed regenerator through the regenerator distributor, and contacts with the catalyst to be regenerated from the fluidized bed reactor, the coke on the catalyst to be regenerated reacts with the regeneration gas to generate flue gas, and at the same time, the catalyst to be regenerated is converted into a regenerated catalyst.
The method for preparing aromatics from naphtha according to claim 34, characterized in that the method further comprises: the catalyst to be regenerated sequentially passes through the reactor stripper, the slide valve to be regenerated and the regenerated catalyst delivery pipe into the fluidized bed regenerator, contacts and reacts with the regeneration gas to obtain flue gas and regenerated catalyst;

The flue gas enters the gas-solid separation device of the regenerator to remove the regenerated catalyst carried therein, and then enters the gas collecting chamber of the regenerator and enters the downstream section through the flue gas conveying pipe.
The method for producing aromatics from naphtha according to claim 34, characterized in that the regeneration gas is selected from at least one of oxygen, air and oxygen-enriched air.
The method for preparing aromatics from naphtha according to claim 34, characterized in that the process conditions in the regeneration zone are: gas superficial velocity of 0.5-2.0 m/s, regeneration temperature of 600-750°C, regeneration pressure of 100-500 kPa, and bed density of 150-700 kg/m 3 .