NAPHTHA-TO-AROMATICS FLUIDIZED BED DEVICE AND METHOD

Abstract

A naphtha-to-aromatics fluidized bed device and a method thereof are provided. The device at least includes: a light hydrocarbon aromatization reactor; and a naphtha-to-aromatics reactor; the high-temperature regenerated catalyst is first directed into the light hydrocarbon aromatization reactor, and after cooling, subsequently introduced into the naphtha-to-aromatics reactor. The method includes using the above-mentioned device and a metal molecular sieve bifunctional catalyst. Under the action of the catalyst in the naphtha to aromatics reactor, naphtha is converted into a product gas containing aromatics, light alkanes, and other components. Light alkanes and the like separated from the product gas are further converted into aromatics and other components in the light hydrocarbon aromatization reactor. The method enables efficient and highly selective conversion of linear and branched aliphatic hydrocarbons into aromatics, with para-xylene content in the xylene mixture exceeding >50 wt %.

Claims

1. A naphtha-to-aromatics fluidized bed device, wherein the device comprises: a light hydrocarbon aromatization reactor and a naphtha-to-aromatics reactor; wherein the light hydrocarbon aromatization reactor comprises at least one inlet for introducing a raw material and a high-temperature catalyst; and at least one outlet of the light hydrocarbon aromatization reactor is connected to the naphtha-to-aromatics reactor for delivering the catalyst and a generated light hydrocarbon aromatization product gas to the naphtha-to-aromatics reactor; the naphtha-to-aromatics reactor is configured to introduce naphtha to react with the catalyst from the light hydrocarbon aromatization reactor to produce a product gas flow containing benzene, toluene, and xylene (BTX).

2. The naphtha-to-aromatics fluidized bed device according to claim 1, wherein the naphtha-to-aromatics reactor is further provided with a first product gas delivery pipe for outputting the product gas flow containing BTX to a downstream section.

3. The naphtha-to-aromatics fluidized bed device according to claim 1, wherein the device further comprises a regenerator, and the at least one inlet of the light hydrocarbon aromatization reactor is connected to the regenerator for obtaining a high-temperature regenerated catalyst generated by the regenerator.

4. The naphtha-to-aromatics fluidized bed device according to claim 1, wherein the light hydrocarbon aromatization reactor is divided from top to bottom into at least a second gas-solid separation zone and a light hydrocarbon aromatization reaction zone which are connected to form a bed reactor; the second gas-solid separation zone is provided with a second gas-solid separation unit and a second gas collection chamber, a gas outlet of the second gas-solid separation unit is connected to the second gas collection chamber, and a bed reactor distributor is provided in an inner lower part of the light hydrocarbon aromatization reaction zone for feeding a bed reactor feedstock.

5. The naphtha-to-aromatics fluidized bed device according to claim 4, wherein the second gas collection chamber is located at an inner top of the bed reactor.

6. The naphtha-to-aromatics fluidized bed device according to claim 4, wherein the bed reactor feedstock comprises C.sub.4 and C.sub.5 hydrocarbons; the light hydrocarbon aromatization reactor further comprises a riser reactor in addition to the bed reactor, wherein an inlet end of the riser reactor is connect to the regenerator; an outlet end of the riser reactor extends into a lower section of the light hydrocarbon aromatization reaction zone, with a catalyst outlet of the second gas-solid separation unit located above it; the inlet end of the riser reactor is further configured to introduce the catalyst and a riser reactor feedstock.

7-8. (canceled)

9. The naphtha-to-aromatics fluidized bed device according to claim 1, wherein the naphtha-to-aromatics reactor is divided from top to bottom into at least a first gas-solid separation zone and a naphtha-to-aromatics reaction zone which are connected; the first gas-solid separation zone is provided with a first gas-solid separation unit and a first gas collection chamber; a gas outlet of the first gas-solid separation unit is connect to the first gas collection chamber; a lower section of the naphtha-to-aromatics reaction zone is provided with a naphtha-to-aromatics reactor distributor for feeding a naphtha feedstock.

10. The naphtha-to-aromatics fluidized bed device according to claim 9, wherein the first gas-solid separation unit employs at least one set of gas-solid cyclone separators, each set comprises a first-stage gas-solid cyclone separator and a second-stage gas-solid cyclone separator; wherein the first gas collection chamber is located at an inner top of the naphtha-to-aromatics reactor; wherein the first gas collection chamber is connected to a first product gas delivery pipe.

11-12. (canceled)

13. The naphtha-to-aromatics fluidized bed device according to claim 9, wherein the first gas-solid separation zone is connected to a second gas-solid separation zone, and the naphtha-to-aromatics reaction zone of the naphtha-to-aromatics reactor is connected to a light hydrocarbon aromatization reaction zone; wherein the first gas-solid separation zone is connected to a second gas collection chamber through a second product gas delivery pipe; wherein a light hydrocarbon aromatization slide valve is provided on a pipeline connecting the naphtha-to-aromatics reaction zone of the naphtha-to-aromatics reactor and the light hydrocarbon aromatization reaction zone; wherein an outlet of the light hydrocarbon aromatization reaction zone is positioned higher than an inlet of the naphtha-to-aromatics reaction zone of the naphtha-to-aromatics reactor.

14-16. (canceled)

17. The naphtha-to-aromatics fluidized bed device according to claim 3, wherein the regenerator is divided from top to bottom into at least a third gas-solid separation zone and a catalyst regeneration zone which are connected; the third gas-solid separation zone is provided with a regenerator gas-solid separation unit and a regenerator gas collection chamber; a gas outlet of the regenerator gas-solid separation unit is connected to the regenerator gas collection chamber; the regenerator gas collection chamber is provided with a flue gas delivery pipe; a lower section of the catalyst regeneration zone is provided with a regenerator distributor for introducing a regeneration gas; wherein the catalyst regeneration zone is sequentially connected to the light hydrocarbon aromatization reactor through a regenerator stripper and a regenerated catalyst slide valve; an inlet pipe of the regenerator stripper extends into a regenerator shell, located above the regenerator distributor, and a catalyst outlet end of the regenerator gas-solid separation unit is located above an open end of the inlet pipe of the regenerator stripper; wherein the regenerator gas collection chamber is located at an inner top of the regenerator shell; wherein at least one outlet of the naphtha-to-aromatics reactor is further connected to an inlet of the regenerator for delivering a spent catalyst generated in the naphtha-to-aromatics reactor to the regenerator, wherein the regenerator is configured to introduce the regeneration gas and convert the spent catalyst into the regenerated catalyst; wherein a naphtha-to-aromatics reaction zone of the naphtha-to-aromatics reactor is sequentially connected to the inlet of the regenerator through a reactor stripper, a spent catalyst slide valve, and a spent catalyst delivery pipe; an inlet pipe of the reactor stripper extends into a naphtha-to-aromatics reactor shell, located above a naphtha-to-aromatics reactor distributor, and a catalyst outlet end of a first gas-solid separation unit is located above an open end of the inlet pipe of the reactor stripper; wherein the catalyst inlet of the regenerator is provided on the regenerator shell.

18-19. (canceled)

20. The naphtha-to-aromatics fluidized bed device according to claim 3, wherein at least one outlet of the naphtha-to-aromatics reactor is further connected to an inlet of the regenerator for delivering a spent catalyst generated in the naphtha-to-aromatics reactor to the regenerator, wherein the regenerator is configured to introduce a regeneration gas and convert the spent catalyst into the regenerated catalyst; wherein a naphtha-to-aromatics reaction zone of the naphtha-to-aromatics reactor is sequentially connected to the inlet of the regenerator through a reactor stripper, a spent catalyst slide valve, and a spent catalyst delivery pipe; an inlet pipe of the reactor stripper extends into a naphtha-to-aromatics reactor shell, located above a naphtha-to-aromatics reactor distributor, and a catalyst outlet end of a first gas-solid separation unit is located above an open end of the inlet pipe of the reactor stripper; wherein the catalyst inlet of the regenerator is provided on a regenerator shell.

21-22. (canceled)

23. A method for producing aromatics from naphtha, wherein the method comprises: using the naphtha-to-aromatics fluidized bed device according to claim 1 to prepare aromatics; wherein the method comprises: introducing the raw material and the high-temperature catalyst into the light hydrocarbon aromatization reactor to generate the light hydrocarbon aromatization product gas; introducing naphtha and the catalyst and the light hydrocarbon aromatization product gas from the light hydrocarbon aromatization reactor into the naphtha-to-aromatics reactor to generate the product gas flow containing BTX; wherein the catalyst is a metal molecular sieve bifunctional catalyst; wherein the metal molecular sieve bifunctional catalyst employs a metal-modified HZSM-5 zeolite molecular sieve; a metal used for a metal modification is at least one selected from the group consisting of La, Zn, Ga, Fe, Mo, and Cr; the metal modification comprises: placing an HZSM-5 zeolite molecular sieve in a metal salt solution, and carrying out an impregnation, a drying, and a calcination to obtain the metal-modified HZSM-5 zeolite molecular sieve.

24-26. (canceled)

27. The method for producing aromatics from naphtha according to claim 23, wherein components of the light hydrocarbon aromatization product gas comprise: BTX, light olefins, and H.sub.2; wherein in addition to BTX, the product gas flow containing BTX further comprises: light olefins, hydrogen, light alkanes, combustible gas, heavy aromatics, and unconverted naphtha.

28-30. (canceled)

31. The method for producing aromatics from naphtha according to claim 23, wherein introducing the raw material and the high-temperature catalyst into the light hydrocarbon aromatization reactor to generate the light hydrocarbon aromatization product gas specifically comprises: feeding the a bed reactor feedstock into a light hydrocarbon aromatization reaction zone through a bed reactor distributor, contacting with the catalyst introduced into a bed reactor to generate the light hydrocarbon aromatization product gas; wherein the bed reactor feedstock comprises C.sub.3, C.sub.4, and C.sub.5 hydrocarbons; wherein the C.sub.3, C.sub.4, and C.sub.5 hydrocarbons are derived from C.sub.3, C.sub.4, and C.sub.5 hydrocarbons separated from the product gas flow; wherein process conditions for the light hydrocarbon aromatization reaction zone are: gas superficial velocity of 0.5-2.0 m/s, reaction temperature of 550-665 C., reaction pressure of 100-500 kPa, bed density of 150-700 kg/m.sup.3.

32-36. (canceled)

37. The method for producing aromatics from naphtha according to claim 31, wherein the method further comprises: removing the catalyst entrained in the light hydrocarbon aromatization product gas in a second gas-solid separation zone of the light hydrocarbon aromatization reactor; wherein the catalyst in the light hydrocarbon aromatization reaction zone enters the naphtha-to-aromatics reactor through a light hydrocarbon aromatization slide valve; wherein removing the catalyst entrained in the light hydrocarbon aromatization product gas in the second gas-solid separation zone specifically comprises: the light hydrocarbon aromatization product gas enters a second gas-solid separation unit to remove the catalyst entrained in it, then enters a second gas collection chamber, and is delivered to a first gas-solid separation zone of the naphtha-to-aromatics reactor through a second product gas delivery pipe.

38-39. (canceled)

40. The method for producing aromatics from naphtha according to claim 23, wherein introducing the naphtha into a naphtha-to-aromatics reaction zone of the naphtha-to-aromatics reactor through a naphtha-to-aromatics reactor distributor, contacting with the catalyst from the light hydrocarbon aromatization reactor to generate the product gas flow containing BTX, while the catalyst becomes coked and converts into the-a spent catalyst; wherein the method further comprises: removing the spent catalyst entrained in the product gas flow containing BTX in a first gas-solid separation zone of the naphtha-to-aromatics reactor and delivering to a downstream section; wherein process conditions for the naphtha-to-aromatics 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, bed density of 150-700 kg/m.sup.3.

41. (canceled)

42. The method for producing aromatics from naphtha according to claim 23, wherein the naphtha is at least one selected from the group consisting of coal direct liquefaction naphtha, coal indirect liquefaction naphtha, straight-run naphtha, and hydrocracked naphtha; wherein the naphtha further comprises unconverted naphtha separated from the product gas flow, wherein main components of the unconverted naphtha are linear aliphatic hydrocarbons, branched aliphatic hydrocarbons, and naphthenes of C.sub.4-C.sub.12.

43-44. (canceled)

45. The method for producing aromatics from naphtha according to claim 23, wherein the method further comprises: introducing the a regeneration gas and the a spent catalyst into a regenerator to obtain a high-temperature regenerated catalyst, which is delivered to the light hydrocarbon aromatization reactor; wherein the regeneration gas is introduced into a regeneration zone of the regenerator through a regenerator distributor; wherein the regeneration gas is at least one selected from the group consisting of oxygen, air, and oxygen-enriched air; wherein a carbon content in the spent catalyst is in a range from 1.0 wt % to 3.0 wt %; wherein a carbon content in the regenerated catalyst is 0.5 wt %; wherein process conditions for the regeneration zone of the regenerator are: gas superficial velocity of 0.5-2.0 m/s, regeneration temperature of 600-750 C., regeneration pressure of 100-500 kPa, bed density of 150-700 kg/m.sup.3; wherein a coke on the spent catalyst reacts with the regeneration gas to generate a flue gas; the flue gas enters a third gas-solid separation zone to remove the regenerated catalyst entrained in it; wherein the flue gas entering the third gas-solid separation zone to remove the regenerated catalyst entrained in it specifically comprises: the flue gas first enters a regenerator gas-solid separation unit to remove the regenerated catalyst entrained in it, then flows through a regenerator gas collection chamber and a flue gas delivery pipe to enter a downstream section; wherein the regenerated catalyst enters the light hydrocarbon aromatization reactor through a regenerator stripper and a regenerated catalyst slide valve.

46-53. (canceled)

54. The method for producing aromatics from naphtha according to claim 23, wherein the method further comprises: feeding a riser reactor feedstock into an inlet end of a riser reactor of the light hydrocarbon aromatization reactor; a regenerated catalyst flows through the a regenerator stripper and a regenerated catalyst slide valve into the riser reactor, wherein the riser reactor feedstock is converted into a BTX-containing flow under an action of the regenerated catalyst, which then enters the a lower section of a light hydrocarbon aromatization reaction zone in a bed reactor through an outlet end of the riser reactor; wherein the method further comprises: introducing the catalyst into an inlet end of the riser reactor of the light hydrocarbon aromatization reactor, which enters the bed reactor through the riser reactor; wherein the riser reactor feedstock comprises water vapor and light alkanes separated from the product gas flow; wherein a water vapor content in the riser reactor feedstock is in a range from 0 wt % to 80 wt %; wherein process conditions for the riser reactor are: gas superficial velocity of 3.0-10.0 m/s, temperature of 580-700 C., pressure of 100-500 kPa, bed density of 50 -150 kg/m.sup.3: wherein components of the BTX-containing flow comprise: BTX, light olefins, and H.sub.2.

55-59. (canceled)

60. The method for producing aromatics from naphtha according to claim 23, wherein the method further comprises: a spent catalyst in a naphtha-to-aromatics reaction zone of the naphtha-to-aromatics reactor is introduced into a reactor stripper, stripped, and then flows through a spent catalyst slide valve and spent catalyst delivery pipe into a downstream section; wherein the downstream section is a regenerator.

61. (canceled)

Description

LIST OF COMPONENTS AND REFERENCE NUMERALS

[0105] 1: naphtha-to-aromatics reactor; 1-1: naphtha-to-aromatics reactor shell; 1-2: naphtha-to-aromatics reactor distributor; 1-3: gas-solid separation unit I; 1-4 gas collection chamber I; 1-5: product gas delivery pipe I; 1-6: reactor stripper; 1-7: spent catalyst slide valve; 1-8: spent catalyst delivery pipe; [0106] 2: regenerator; 2-1: regenerator shell; 2-2: regenerator distributor; 2-3: regenerator gas-solid separation unit; 2-4: regenerator gas collection chamber; 2-5: flue gas delivery pipe; 2-6: regenerator stripper; 2-7: regenerated catalyst slide valve; [0107] 3: light hydrocarbon aromatization reactor; 3-1: inlet end of the riser reactor; 3-2: middle section of the riser reactor; 3-3: outlet end of the riser reactor; 3-4: bed reactor shell; 3-5 bed reactor distributor; 3-6: gas-solid separation unit II; 3-7: gas collection chamber II; 3-8: product gas delivery pipe II; 3-9: light hydrocarbon aromatization slide valve.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0108] The present application will be described in detail below with reference to examples, but the present application is not limited to these examples.

[0109] The present application provides naphtha-to-aromatics fluidized bed device, including a light hydrocarbon aromatization reactor; and a naphtha-to-aromatics reactor; wherein [0110] the light hydrocarbon aromatization reactor includes at least one inlet for introducing a raw material and a high-temperature catalyst; and at least one outlet of the light hydrocarbon aromatization reactor is connected to the naphtha-to-aromatics reactor for delivering a catalyst and a generated light hydrocarbon aromatization product gas to the naphtha-to-aromatics reactor; [0111] the naphtha-to-aromatics reactor is configured to introduce naphtha to react with a catalyst from the light hydrocarbon aromatization reactor to produce a product gas flow containing BTX.

[0112] In the present application, the components of the naphtha include C.sub.4-C.sub.12 linear aliphatic hydrocarbons, branched aliphatic hydrocarbons, naphthenes, and aromatics.

[0113] In the present application, the term aromatics refers to benzene, toluene, and xylene, collectively termed BTX.

[0114] In a preferred embodiment, the naphtha-to-aromatics reactor is further provided with a product gas delivery pipe I for outputting the product gas flow containing BTX to a downstream section.

[0115] In a preferred embodiment, the device further includes a regenerator, and at least one inlet of the light hydrocarbon aromatization reactor is connected to the regenerator for obtaining a high-temperature regenerated catalyst generated by the regenerator.

[0116] Please refer to the figure, which shows a preferred embodiment of naphtha-to-aromatics fluidized bed device in the present application. The device includes a naphtha-to-aromatics reactor 1, a regenerator 2, and a light hydrocarbon aromatization reactor 3.

[0117] The naphtha-to-aromatics reactor 1 includes: a naphtha-to-aromatics reactor shell 1-1, a naphtha-to-aromatics reactor distributor 1-2, a gas-solid separation unit I 1-3, a gas collection chamber I 1-4, a product gas delivery pipe I 1-5, a reactor stripper 1-6; a spent catalyst slide valve 1-7, a spent catalyst delivery pipe 1-8.

[0118] The naphtha-to-aromatics reactor shell 1-1 includes a reactor upper shell and a reactor lower shell. The reactor upper shell encloses a gas-solid separation zone and the reactor lower shell encloses a naphtha-to-aromatics reaction zone; The naphtha-to-aromatics reactor shell 1-1 is equipped with the outlet of the light hydrocarbon aromatization reactor 3.

[0119] The naphtha-to-aromatics reaction zone is equipped with the distributor 1-2 at its lower section for introducing naphtha feedstock.

[0120] The naphtha-to-aromatics reactor shell 1-1 houses the gas-solid separation unit I 1-3 and gas collection chamber I 1-4; The chamber I 1-4, located at the naphtha-to-aromatics reactor shell's inner top, connects to the gas outlet of the gas-solid separation unit I 1-3 and the product gas delivery pipe I 1-5. The catalyst outlet of separation unit I 1-3 is positioned above the open end of the reactor stripper 1-6 inlet pipe.

[0121] The reactor stripper 1-6 is located below the naphtha-to-aromatics reaction zone; the inlet of the reactor stripper 1-6 is located inside the naphtha-to-aromatics reactor shell 1-1; and the outlet of the reactor stripper 1-6 located outside the naphtha-to-aromatics reactor shell 1-1 and is connected to the spent catalyst slide valve I 1-7; the open end of the inlet of the reactor stripper 1-6 is located above the naphtha-to-aromatics reactor distributor 1-2.

[0122] The spent catalyst slide valve 1-7 is provided below the reactor stripper 1-6; the inlet of the spent catalyst slide valve 1-7 is connected to the outlet of the reactor stripper 1-6, the outlet of the spent catalyst slide valve 1-7 is connected to the inlet of the spent catalyst delivery pipe 1-8, and the outlet of the spent catalyst delivery pipe 1-8 is connected to the regenerator shell 2-1.

[0123] The spent catalyst slide valve 1-7 is used to control the circulation amount of the spent catalyst.

[0124] In a preferred embodiment, the gas-solid separation unit I 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.

[0125] The regenerator 2 includes: the regenerator shell 2-1, the regenerator distributor 2-2, the regenerator gas-solid separation unit 2-3, the regenerator gas collection chamber 2-4, the flue gas delivery pipe 2-5, the regenerator stripper 2-6, the regenerated catalyst slide valve 2-7.

[0126] The regenerator shell 2-1 includes the regenerator upper shell and the regenerator lower shell, wherein the regenerator upper shell encloses the gas-solid separation zone, and the regenerator lower shell encloses the regeneration zone; the regenerator shell 2-1 is provided with an outlet of the spent catalyst delivery pipe 1-8.

[0127] The 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.

[0128] The regenerator shell 2-1 is also provided with a regenerator gas-solid separation unit 2-3 and a regenerator gas collection chamber 2-4; the regenerator gas collection chamber 2-4 is located at the inner top of the regenerator shell 2-1; the gas outlet of the regenerator gas-solid separation unit 2-3 is connected to the regenerator gas collection chamber 2-4; the regenerator gas collection chamber 2-4 is connected to the flue gas delivery pipe 2-5; the catalyst outlet end of the regenerator gas-solid separation unit 2-3 is located above the opening end of the inlet pipe of the regenerator stripper 2-6.

[0129] The 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 regenerated catalyst slide valve 2-7; the opening end of the inlet of the regenerator stripper 2-6 is located above the regenerator distributor 2-2.

[0130] The regenerator stripper 2-6 is equipped with the regenerated catalyst slide valve 2-7 beneath it, the outlet of the regenerator stripper 2-6 is connected to the inlet of the regenerated catalyst slide valve 2-7.

[0131] The regenerated catalyst slide valve 2-7 is used to control the circulation amount of the regenerated catalyst.

[0132] In a preferred embodiment, the regenerator gas-solid separation unit 2-3 uses one or more groups of gas-solid cyclone separators, and each group of gas-solid cyclone separators includes the first-stage gas-solid cyclone separator and the second-stage gas-solid cyclone separator.

[0133] The light hydrocarbon aromatization reactor includes: the inlet end of the riser reactor 3-1, the middle part of the riser reactor 3-2, the outlet end of the riser reactor 3-3, the bed reactor shell 3-4, the bed reactor distributor 3-5, the gas-solid separation unit II 3-6, the gas collection chamber II 3-7, the product gas delivery pipe II 3-8, the light hydrocarbon aromatization slide valve II 3-9.

[0134] The bed reactor shell 3-4 includes an upper shell of the bed reactor and a lower shell of the bed reactor, the upper shell of the bed reactor encloses a gas-solid separation zone, and the lower shell of the bed reactor encloses a light hydrocarbon aromatization reaction zone; the bed reactor distributor 3-5 is provided at the inner lower part of the light hydrocarbon aromatization reaction zone; the light hydrocarbon aromatization slide valve 3-9 is provided at the outside of the light hydrocarbon aromatization reaction zone; the upper section of the riser reactor penetrates the bottom of the bed reactor and is axially inserted in the bed reactor; the outlet end of the riser reactor 3-3 is located at the inner lower part of the light hydrocarbon aromatization reaction zone. The light hydrocarbon aromatization slide valve 3-9 is configured to deliver the catalyst to the next-stage reactor, such as the naphtha-to-aromatics reactor 1. Furthermore, the outlet of the light hydrocarbon aromatization reaction zone is positioned at a higher elevation than the inlet of the naphtha-to-aromatics reaction zone in the naphtha-to-aromatics reactor.

[0135] The gas-solid separation zone of the bed reactor is provided with the gas-solid separation unit II 3-6 and a gas collection chamber II 3-7; the gas outlet of the gas-solid separation unit II 3-6 is connected to the gas collection chamber II 3-7; the catalyst outlet of the gas-solid separation unit II 3-6 is located in the light hydrocarbon aromatization reaction zone; the gas collection chamber II 3-7 is connected to the product gas delivery pipe II 3-8 located outside the bed reactor. In a preferred embodiment, the gas-solid separation unit II 3-6 is a gas-solid cyclone separator.

[0136] In a preferred embodiment, the gas collection chamber II 3-7 is provided at the inner top of the bed reactor; the catalyst outlet of the gas-solid cyclone separation unit 3-7 of the bed reactor is located above the outlet end of the riser reactor 3-3.

[0137] In a preferred embodiment, the bed reactor distributor 3-5 is used to introduce the bed reactor feedstock.

[0138] In a preferred embodiment, the inlet end of the riser reactor 3-1 is used to introduce the catalyst and the riser reactor feedstock.

[0139] The inlet of the light hydrocarbon aromatization reactor 3 is connected to the regenerator 2) and its outlet is connected to the naphtha-to-aromatics reactor 1.

[0140] In a preferred embodiment, The inlet end of the riser reactor 3-1 is connected to the regenerated catalyst slide valve 2-7 through a pipeline; the light hydrocarbon aromatization slide valve 3-9 is connected to the naphtha-to-aromatics reactor shell 1-1 through a pipeline.

[0141] In another preferred embodiment, the product gas delivery pipe II 3-8 is connected to the naphtha-to-aromatics reactor shell 1-1.

[0142] In order to achieve aromatization of liner and branched aliphatic hydrocarbons, increase the yield of aromatic hydrocarbons and the content of p-xylene in mixed xylenes, the present application provides a method for preparing aromatic hydrocarbons from naphtha, the method using any of the above-mentioned naphtha-to-aromatics devices.

[0143] Furthermore, the method includes: introducing a raw material and a high-temperature catalyst into the light hydrocarbon aromatization reactor to produce a light hydrocarbon aromatization product gas; [0144] introducing naphtha, the catalyst from the light hydrocarbon aromatization reactor, and the light hydrocarbon aromatization product gas into the naphtha-to-aromatics reactor to generate a product gas flow containing BTX.

[0145] In a preferred embodiment, the catalyst is a metal molecular sieve bifunctional catalyst.

[0146] The metal molecular sieve bifunctional catalyst adopts metal-modified HZSM-5 zeolite molecular sieve; [0147] the metal used for metal modification is at least one selected from the group consisting of La, Zn, Ga, Fe, Mo, and Cr; [0148] the metal modification method includes: 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.

[0149] In a preferred embodiment, the method includes the following steps: [0150] a) naphtha enters the naphtha-to-aromatics reaction zone of the naphtha-to-aromatics reactor 1 through the naphtha-to-aromatics reactor distributor 1-2, contacts with the catalyst from the light hydrocarbon aromatization reactor 3, generates a product gas flow 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 the spent catalyst; [0151] the product gas flow enters the gas-solid separation unit I 1-3 to remove the spent catalyst carried therein, then enters the gas collection chamber I 1-4, and enters the downstream section through the product gas delivery pipe I 1-5; the spent catalyst in the naphtha-to-aromatics reaction zone enters the reactor stripper 1-6 through the open end of the inlet pipe of the reactor stripper 1-6, is stripped, and after stripping, enters the regenerator 2 through the spent catalyst slide valve 1-7 and the spent catalyst delivery pipe 1-8; [0152] b) passing the regenerated gas into the regeneration zone of the regenerator 2 through the regenerator distributor 2-2, and contacting with the spent catalyst, the coke on the spent catalyst reacts with the regenerated gas to generate flue gas, and at the same time, the spent catalyst is converted into the regenerated catalyst; the flue gas enters the regenerator gas-solid separation unit 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 delivery pipe 2-5; the regenerated catalyst passes through the regenerator stripper 2-6, the regenerated catalyst slide valve 2-7 in sequence to enter the light hydrocarbon aromatization reactor 3; [0153] c) feeding the riser reactor feedstock into the riser reactor through the inlet end of the riser reactor 3-1, contacting and reacting with the regenerated catalyst from the regenerator, and converting the riser reactor feedstock into a flow containing components such as BTX, light olefins and H.sub.2 under the action of the catalyst, and then entering the inner lower part of the light hydrocarbon aromatization reaction zone in the bed reactor through the outlet end of the riser reactor 3-3; feeding the bed reactor feedstock into the light hydrocarbon aromatization reaction zone through the bed reactor distributor 3-5, contacting with the catalyst from the riser reactor, and generating a light hydrocarbon aromatization product gas containing components such as BTX, light olefins and H.sub.2; the light hydrocarbon aromatization product gas enters the gas-solid separation unit II 3-6 to remove the catalyst carried therein, and then enters the gas collection chamber II 3-7, and then enters the gas-solid separation zone of the naphtha-to-aromatics reactor through the product gas delivery pipe II 3-8; the catalyst in the light hydrocarbon aromatization reaction zone passes through the light hydrocarbon aromatization slide valve 3-9 to enter the naphtha-to-aromatics reactor 1.

[0154] The light olefins are ethylene and propylene.

[0155] The light alkanes are ethane and propane.

[0156] The combustible gas includes methane, CO and the like.

[0157] The heavy aromatic hydrocarbons refer to aromatic hydrocarbons having 9 or more carbon atoms in the molecule.

[0158] 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.

[0159] In a preferred embodiment, the naphtha further includes unconverted naphtha separated from the product gas flow.

[0160] In a preferred embodiment, the carbon content in the spent catalyst is in a range from 1.0 wt % to 3.0 wt %.

[0161] In a preferred embodiment, the process conditions for the naphtha-to-aromatics 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, bed density of 150-700 kg/m.sup.3.

[0162] Optionally, the gas superficial velocity is independently selected from any value among 0.5 m/s, 0.6 m/s, 0. 7m/s, 0.8 m/s, 0.9 m/s, 1.0 m/s, 1.1 m/s, 1.2 m/s, 1.3 m/s, 1.4 m/s, 1.5 m/s, 1.6 m/s, 1.7 m/s, 1.8 m/s, 1.9 m/s, 2.0 m/s or any range between two values.

[0163] Optionally, the reaction temperature is independently selected from any value among 500 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 values.

[0164] Optionally, the reaction pressure is independently selected from any value among 100kPa, 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 values.

[0165] Optionally, the bed density is independently selected from any value among 150 kg/m.sup.3, 200 kg/m.sup.3, 250 kg/m.sup.3, 300 kg/m.sup.3, 350 kg/m.sup.3, 400 kg/m.sup.3, 450 kg/m.sup.3, 500 kg/m.sup.3, 550 kg/m.sup.3, 600 kg/m.sup.3, 650 kg/m.sup.3, 700 kg/m.sup.3 or any range between two values.

[0166] In a preferred embodiment, the carbon content in the regenerated catalyst is 0.5 wt %.

[0167] In a preferred embodiment, the regeneration gas is at least one selected from the group consisting of oxygen, air and oxygen-enriched air.

[0168] In a preferred embodiment, the process conditions for the regeneration zone of the regenerator are: gas superficial velocity of 0.5-2.0 m/s, regeneration temperature of 600-750 C., regeneration pressure of 100-500 kPa, bed density of 150-700 kg/m.sup.3.

[0169] Optionally, the gas superficial velocity is independently selected from any value among 0.5 m/s, 0.6 m/s, 0.7 m/s, 0.8 m/s, 0.9 m/s, 1.0 m/s, 1.1m/s, 1.2m/s, 1.3 m/s, 1.4 m/s, 1.5 m/s, 1.6 m/s, 1.7 m/s, 1.8 m/s, 1.9 m/s, 2.0 m/s or any range between two values.

[0170] Optionally, the regeneration temperature is independently selected from any value among 600 C., 615 C., 630 C., 645 C., 670 C., 685 C., 700 C., 715 C., 730 C., 745 C., 750 C. or any range between two values.

[0171] Optionally, the regeneration pressure 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 between two values.

[0172] Optionally, the bed density is independently selected from any value among 150 kg/m.sup.3, 200 kg/m.sup.3, 250 kg/m.sup.3, 300 kg/m.sup.3, 350kg/m.sup.3, 400 kg/m.sup.3, 450 kg/m, 500 kg/m.sup.3, 550 kg/m.sup.3, 600 kg/m.sup.3, 650 kg/m.sup.3, 700 kg/m.sup.3 or any range between two values.

[0173] In a preferred embodiment, the riser reactor feedstock includes water vapor and light alkanes separated from the product gas flow.

[0174] In a preferred embodiment, the water vapor content in the riser reactor feedstock is in a range from 0 wt % to 80 wt %.

[0175] In a preferred embodiment, the process conditions for the riser reactor are: gas superficial velocity of 3.0-10.0 m/s, temperature of 580-700 C., pressure of 100-500 kPa, bed density of 50 -150 kg/m.sup.3.

[0176] Optionally, the gas superficial velocity for the riser reactor is independently selected from any value among 3.0 m/s, 3.5 m/s, 4.0 m/s, 4.5m/s, 5.0 m/s, 5.5 m/s, 6.0 m/s, 6.5 m/s, 7.0 m/s, 7.5 m/s, 8.0 m/s, 8.5 m/s, 9.0 m/s, 9.5m/s, 10.0m/s or any range between two values.

[0177] 45 Optionally, the temperature for the riser reactor is independently selected from any value among 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 between two values.

[0178] Optionally, the pressure of the riser reactor 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 between two values.

[0179] Optionally, the bed density for the riser reactor is independently selected from any value among 50 kg/m.sup.b 3, 60 kg/m.sup.3, 70 kg/m.sup.3, 80 kg/m.sup.3, 90 kg/m.sup.3, 100 kg/m.sup.3, 110 kg/m.sup.3, 120 kg/m.sup.3, 130 kg/m.sup.3, 140 kg/m.sup.3, 150 kg/m.sup.3 or any range between two values.

[0180] The bed reactor feedstock includes C.sub.4 and C.sub.5 hydrocarbons.

[0181] In a preferred embodiment, the bed reactor feedstock includes C.sub.3, C.sub.4 and C.sub.5 hydrocarbons. In a preferred embodiment, the C.sub.3, C.sub.4 and C.sub.5 hydrocarbons are derived from C.sub.3, C.sub.4 and C.sub.5 hydrocarbons separated from the product gas flow.

[0182] The C3, C4 and Cs hydrocarbons refer to hydrocarbons with 3, 4 and 5 carbon atoms.

[0183] In a preferred embodiment, the process conditions for the light hydrocarbon aromatization reaction zone are: gas superficial velocity of 0.5-2.0 m/s, reaction temperature of 550-665 C., reaction pressure of 100-500 kPa, bed density of 150-700 kg/m.sup.3.

[0184] Optionally, the gas superficial velocity for the light hydrocarbon aromatization reaction zone is independently selected from any value among 0.5 m/s, 0.6 m/s, 0.7 m/s, 0.8 m/s, 0.9 m/s, 1.0 m/s, 1.1 m/s, 1.2 m/s, 1.3 m/s, 1.4 m/s, 1.5 m/s, 1.6 m/s, 1.7 m/s, 1.8 m/s, 1.9 m/s, 2.0 m/s or any range between two values.

[0185] Optionally, the reaction temperature for the light hydrocarbon aromatization reaction zone is independently selected from any value among 550 C., 560 C., 570 C., 580 C., 590 C., 600 C., 610 C., 620 C., 630 C., 640 C., 650 C., 660 C., 665 C. or any range between two values.

[0186] Optionally, the reaction pressure for the light hydrocarbon aromatization 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 between two values.

[0187] Optionally, the bed density for the light hydrocarbon aromatization reaction zone is independently selected from any value among 150 kg/m.sup.3, 200 kg/m.sup.3, 250 kg/m.sup.3, 300 kg/m.sup.3, 350 kg/m.sup.3, 400 kg/m.sup.3, 450 kg/m.sup.3, 500 kg/m.sup.3, 550 kg/m.sup.3, 600 kg/m.sup.3, 650 kg/m.sup.3, 700 kg/m.sup.3 or any range between two values.

[0188] In the embodiment described in the present application, the naphtha feedstock has a latent aromatic content of 0-80wt %, the single-pass conversion rate of naphtha is 70-95wt %, the unconverted naphtha is separated from the product gas and returned to the naphtha-to-aromatics reactor as a raw material, some light alkanes are separated from the product gas and returned to the riser reactor in the light hydrocarbon aromatization reactor as a raw material, C.sub.3, C.sub.4 and C.sub.5 hydrocarbons are separated from the product gas and returned to the bed reactor in the light hydrocarbon aromatization reactor as a raw material, and the final product distribution is: 60-75 wt % BTX, 6-14 wt % light olefins, 3-7 wt % hydrogen, 3-8wt % light alkanes, 4-6wt % combustible gas, 4-8 wt % heavy aromatics, and 0.5-1 wt % coke. The content of p-xylene in the mixed xylene in the product is 50-65 wt %.

EXAMPLE 1

[0189] This embodiment employs the device illustrated in the figure.

[0190] Naphtha feedstock fed to the naphtha-to-aromatics reactor is coal direct liquefaction naphtha with an aromatics potential content of 78 wt %, including unconverted naphtha recycled from the separated product gas flow.

[0191] Naphtha-to-aromatics reaction zone conditions: gas superficial velocity is 0.5 m/s, reaction temperature is 645 C., reaction pressure is 100 kPa, bed density is 700 kg/m.sup.3.

[0192] Regeneration gas is air.

[0193] Regeneration zone conditions in the regenerator: gas superficial velocity is 0.5 m/s, regeneration temperature is 745 C., regeneration pressure is 100 kPa, bed density is 700 kg/m.sup.3.

[0194] Riser reactor feedstock is light alkanes separated from the product gas flow.

[0195] Riser reactor conditions: gas superficial velocity is 3.0 m/s, temperature is 690 C., pressure is 100 kPa, bed density is 150 kg/m.sup.3.

[0196] Bed reactor feedstock is C.sub.3, C.sub.4, and C.sub.5 hydrocarbons separated from the product gas flow. Light hydrocarbon aromatization reaction zone conditions: gas superficial velocity is 0.5 m/s, reaction temperature is 665 C., reaction pressure is 100 kPa, bed density is 700 kg/m.sup.3.

[0197] Carbon content in the spend catalyst is 1.2wt %, and carbon content in the regenerated catalyst is 0.2 wt %.

[0198] Single-pass conversion of naphtha feedstock into the naphtha-to-aromatics reactor is 70 wt %.

[0199] Product distribution: 74.4 wt % BTX, 6 wt % light olefins, 3 wt % hydrogen, 4 wt % light alkanes, 5 wt % combustible gas, 7 wt % heavy aromatics, 0.6 wt % coke. The content of p-xylene in the mixed xylene in the product is 51 wt %.

EXAMPLE 2

[0200] This embodiment employs the device illustrated in the figure.

[0201] Naphtha feedstock fed to the naphtha-to-aromatics reactor is coal direct liquefaction naphtha with an aromatics potential content of 0.1 wt %, including unconverted naphtha recycled from the separated product gas flow.

[0202] Naphtha-to-aromatics reaction zone conditions: gas superficial velocity is 2.0 m/s, reaction temperature is 510 C., reaction pressure is 500 kPa, bed density is 150 kg/m.sup.3.

[0203] Regeneration gas is oxygen.

[0204] Regeneration zone conditions in the regenerator: gas superficial velocity is 2.0 m/s, regeneration temperature is 610 C., regeneration pressure is 500 kPa, bed density is 150 kg/m.sup.3.

[0205] Riser reactor feedstock is light alkanes separated from the product gas flow and water vapor, with a water vapor content of 80 wt %.

[0206] Riser reactor conditions: gas superficial velocity is 10.0 m/s, temperature is 580 C., pressure is 500 kPa, bed density is 50 kg/m.sup.3.

[0207] Bed reactor feedstock is C.sub.3, C.sub.4, and C.sub.5 hydrocarbons separated from the product gas flow.

[0208] Light hydrocarbon aromatization reaction zone conditions: gas superficial velocity is 2.0 m/s, reaction temperature is 550 C., reaction pressure is 500 kPa, bed density is 150 kg/m.sup.3.

[0209] Carbon content in the spend catalyst is 2.9 wt %, and carbon content in the regenerated catalyst is 0.1 wt %.

[0210] Single-pass conversion of naphtha feedstock into the naphtha-to-aromatics reactor is 76 wt %.

[0211] Product distribution: 66 wt % BTX, 11.3 wt % light olefins, 6 wt % hydrogen, 3 wt % light alkanes, 5 wt % combustible gas, 8 wt % heavy aromatics, 0.7 wt % coke. The content of p-xylene in the mixed xylene in the product is 62 wt %.

EXAMPLE 3

[0212] This embodiment employs the device illustrated in the figure.

[0213] Naphtha feedstock fed to the naphtha-to-aromatics reactor is coal direct liquefaction naphtha with an aromatics potential content of 3 wt %, including unconverted naphtha recycled from the separated product gas flow.

[0214] Naphtha-to-aromatics reaction zone conditions: gas superficial velocity is 1.2 m/s, reaction temperature is 550 C., reaction pressure is 120 kPa, bed density is 260 kg/m3.

[0215] Regeneration gas is oxygen-enriched air.

[0216] Regeneration zone conditions in the regenerator: gas superficial velocity is 1.2 m/s, regeneration temperature is 650 C., regeneration pressure is 120 kPa, bed density is 260 kg/m3.

[0217] Riser reactor feedstock is light alkanes separated from the product gas flow and water vapor, with a water vapor content of 25 wt %.

[0218] Riser reactor conditions: gas superficial velocity is 7.0 m/s, temperature is 630 C., pressure is 120 kPa, bed density is 80 kg/m.sup.3.

[0219] Bed reactor feedstock is C.sub.4 and C.sub.5 hydrocarbons separated from the product gas flow.

[0220] Light hydrocarbon aromatization reaction zone conditions: gas superficial velocity is 1.2 m/s, reaction temperature is 580 C., reaction pressure is 120 kPa, bed density is 260 kg/m3.

[0221] Carbon content in the spend catalyst is 2.0 wt %, and carbon content in the regenerated catalyst is 0.3 wt %.

[0222] Single-pass conversion of naphtha feedstock into the naphtha-to-aromatics reactor is 94 wt %.

[0223] Product distribution: 60 wt % BTX, 14 wt % light olefins, 7 wt % hydrogen, 8 wt % light alkanes, 4.5 wt % combustible gas, 6 wt % heavy aromatics, 0.5 wt % coke. The content of p-xylene in the mixed xylene in the product is 65 wt %.

EXAMPLE 4

[0224] This embodiment employs the device illustrated in the figure.

[0225] Naphtha feedstock fed to the naphtha-to-aromatics reactor is coal direct liquefaction naphtha with an aromatics potential content of 46 wt %, including unconverted naphtha recycled from the separated product gas flow.

[0226] Naphtha-to-aromatics reaction zone conditions: gas superficial velocity is 1.8 m/s, reaction temperature is 600 C., reaction pressure is 200 kPa, bed density is 220 kg/m.sup.3.

[0227] Regeneration gas is air.

[0228] Regeneration zone conditions in the regenerator: gas superficial velocity is 1.8 m/s, regeneration temperature is 700 C., regeneration pressure is 200 kPa, bed density is 220 kg/m.sup.3.

[0229] Riser reactor feedstock is light alkanes separated from the product gas flow and water vapor, with a water vapor content of 50 wt %.

[0230] Riser reactor conditions: gas superficial velocity is 5.0 m/s, temperature is 660 C., pressure is 220 kPa, bed density is 110 kg/m.sup.3.

[0231] Bed reactor feedstock is C.sub.4 and C.sub.5 hydrocarbons separated from the product gas flow.

[0232] Light hydrocarbon aromatization reaction zone conditions: gas superficial velocity is 1.8 m/s, reaction temperature is 630 C., reaction pressure is 200 kPa, bed density is 220 kg/m.sup.3.

[0233] Carbon content in the spend catalyst is 1.7 wt %, and carbon content in the regenerated catalyst is 0.1 wt %.

[0234] Single-pass conversion of naphtha feedstock into the naphtha-to-aromatics reactor is 87 wt %.

[0235] Product distribution: 70 wt % BTX, 10 wt % light olefins, 6 wt % hydrogen, 5 wt % light alkanes, 4 wt % combustible gas, 4 wt % heavy aromatics, 1.0 wt % coke. The content of p-xylene in the mixed xylene in the product is 63 wt %.

EXAMPLE 5

[0236] This embodiment employs the device illustrated in the figure.

[0237] Naphtha feedstock fed to the naphtha-to-aromatics reactor is coal direct liquefaction naphtha with an aromatics potential content of 64 wt %, including unconverted naphtha recycled from the separated product gas flow.

[0238] Naphtha-to-aromatics reaction zone conditions: gas superficial velocity is 1.0 m/s, reaction temperature is 580 C., reaction pressure is 150 kPa, bed density is 350 kg/m.sup.3.

[0239] Regeneration gas is air.

[0240] Regeneration zone conditions in the regenerator: gas superficial velocity is 1.0 m/s, regeneration temperature is 680 C., regeneration pressure is 150 kPa, bed density is 350 kg/m.sup.3. Riser reactor feedstock is light alkanes separated from the product gas flow and water vapor, with a water vapor content of 40 wt %.

[0241] Riser reactor conditions: gas superficial velocity is 7.0 m/s, temperature is 650 C., pressure is 150 kPa, bed density is 80 kg/m.sup.3.

[0242] Bed reactor feedstock is C.sub.4 and C.sub.5 hydrocarbons separated from the product gas flow.

[0243] Light hydrocarbon aromatization reaction zone conditions: gas superficial velocity is 1.0 m/s, reaction temperature is 610 C., reaction pressure is 150 kPa, bed density is 350 kg/m.sup.3.

[0244] Carbon content in the spend catalyst is 1.5 wt %, and carbon content in the regenerated catalyst is 0.5 wt %.

[0245] Single-pass conversion of naphtha feedstock into the naphtha-to-aromatics reactor is 77 wt %.

[0246] Product distribution: 71 wt % BTX, 8 wt % light olefins, 5 wt % hydrogen, 3 wt % light alkanes, 6 wt % combustible gas, 6 wt % heavy aromatics, 1.0 wt % coke. The content of p-xylene in the mixed xylene in the product is 57 wt %.

[0247] 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.