REACTION DEVICE FOR PREPARING LIGHT OLEFINS FROM METHANOL AND/OR DIMETHYL ETHER

Abstract

A reaction device for preparing light olefins from methanol and/or dimethyl ether, and more specifically relates to a reaction device for preparing light olefins from methanol and/or dimethyl ether, which mainly comprises a dense phase fluidized bed reactor (2), a cyclone separator (3), a stripper (5), a lift pipe (7), a dense phase fluidized bed regenerator (10), a cyclone separator (11), a stripper (13), and a lift pipe (15), wherein the dense phase fluidized bed reactor (2) is separated into n (n2) secondary reaction zones by a material flow controller (17), and the dense phase fluidized bed regenerator (10) is separated into m (m2) secondary regeneration zones by the material flow controller (17).

Claims

1. A reaction device for preparing light olefins from methanol and/or dimethyl ether comprising a dense phase fluidized bed reactor, a cyclone separator, a stripper, a lift pipe, a dense phase fluidized bed regenerator, a cyclone separator, a stripper, and a lift pipe; wherein a feeding line for reactor is connected to the bottom of the dense phase fluidized bed reactor; a part of the stripper is in the dense phase fluidized bed reactor, and the remaining part thereof is below the dense phase fluidized bed reactor; the bottom of the lift pipe is connected to the bottom of the stripper, and the top of the lift pipe is connected to the dense phase fluidized bed regenerator; a feeding line for regenerator is connected to the bottom of the dense phase fluidized bed regenerator; a part of the stripper is in the dense phase fluidized bed regenerator, and the remaining part thereof is below the dense phase fluidized bed regenerator; the bottom of the lift pipe is connected to the bottom of the stripper, and the top of the lift pipe is connected to the dense phase fluidized bed reactor, wherein a material flow controller is provided in the dense phase fluidized bed reactor and/or the dense phase fluidized bed regenerator, and the dense phase fluidized bed reactor is separated into n secondary reaction zones by the material flow controller and the 1.sup.st to the n.sup.th secondary reaction zones are sequentially connected; the dense phase fluidized bed regenerator is separated into m secondary regeneration zones by the material flow controller and the 1.sup.st to the m.sup.th secondary regeneration zones are sequentially connected; and wherein n2, and m2.

2. The reaction device according to claim 1, wherein the top of the lift pipe is connected to the 1.sup.st secondary reaction zone, the n.sup.th secondary reaction zone is connected to a material overflow port on the upper part of the stripper; and the cyclone separator is provided on the upper part of the dense phase fluidized bed reactor, a top outlet of the cyclone separator is connected to a product material line, and the bottom of the cyclone separator is connected to the n.sup.th secondary reaction zone.

3. The reaction device according to claim 1, wherein top of the lift pipe is connected to the 1.sup.st secondary regeneration zone, the m.sup.th secondary regeneration zone is connected to a material overflow port on the upper part of the stripper; and the cyclone separator is provided on the upper part of the dense phase fluidized bed regenerator, a top outlet of the cyclone separator is connected to an exhaust gas line, and the bottom of the cyclone separator is connected to the m.sup.th secondary regeneration zone.

4. The reaction device according to claim 1, wherein 8n3.

5. The reaction device according to claim 1, wherein 8m3.

6. The reaction device according to claim 1, wherein the material flow controller is composed of a partition plate, an orifice, a material downward flow pipe, a bottom baffle, and a heat extraction member; and the orifice is located below the partition plate and is connected to the bottom of the material downward flow pipe, the bottom baffle is located at the bottom of the material downward flow pipe and the orifice, and the heat extraction member is fixed on the partition plate.

7. The reaction device according to claim 6, wherein the bottom baffle is a porous plate or a nonporous plate.

8. The reaction device according to claim 2, wherein the material flow controller is composed of a partition plate, an orifice, a material downward flow pipe, a bottom baffle, and a heat extraction member; and the orifice is located below the partition plate and is connected to the bottom of the material downward flow pipe, the bottom baffle is located at the bottom of the material downward flow pipe and the orifice, and the heat extraction member is fixed on the partition plate.

9. The reaction device according to claim 3, wherein the material flow controller is composed of a partition plate, an orifice, a material downward flow pipe, a bottom baffle, and a heat extraction member; and the orifice is located below the partition plate and is connected to the bottom of the material downward flow pipe, the bottom baffle is located at the bottom of the material downward flow pipe and the orifice, and the heat extraction member is fixed on the partition plate.

10. The reaction device according to claim 4, wherein the material flow controller is composed of a partition plate, an orifice, a material downward flow pipe, a bottom baffle, and a heat extraction member; and the orifice is located below the partition plate and is connected to the bottom of the material downward flow pipe, the bottom baffle is located at the bottom of the material downward flow pipe and the orifice, and the heat extraction member is fixed on the partition plate.

11. The reaction device according to claim 5, wherein the material flow controller is composed of a partition plate, an orifice, a material downward flow pipe, a bottom baffle, and a heat extraction member; and the orifice is located below the partition plate and is connected to the bottom of the material downward flow pipe, the bottom baffle is located at the bottom of the material downward flow pipe and the orifice, and the heat extraction member is fixed on the partition plate.

12. The reaction device according to claim 7, wherein the bottom baffle is a porous plate or a nonporous plate.

13. The reaction device according to claim 8, wherein the bottom baffle is a porous plate or a nonporous plate.

14. The reaction device according to claim 9, wherein the bottom baffle is a porous plate or a nonporous plate.

15. The reaction device according to claim 10, wherein the bottom baffle is a porous plate or a nonporous plate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG. 1 shows a schematic flow chart of the method in this invention;

[0029] FIG. 2 shows a structural schematic diagram of the dense phase fluidized bed comprising 4 secondary reaction zones in this invention, wherein the arrows in A-A sectional view show the flow directions of the catalyst between the secondary reaction zones;

[0030] FIG. 3 shows a structural schematic diagram of the dense phase fluidized bed comprising 4 secondary regeneration zones in this invention, wherein the arrows in B-B sectional view show the flow directions of the catalyst between the secondary regeneration zones;

[0031] FIG. 4 shows a structural schematic diagram of the stripper in this invention; and

[0032] FIG. 5 shows a structural schematic diagram of the material flow controller in this invention.

[0033] Reference numerals in the accompanying drawings are described as follows: [0034] 1feeding line for reactor; 1-1 1.sup.st secondary reaction zone feed branch line; 1-2 2.sup.nd secondary reaction zone feed branch line; 1-3 3.sup.rd secondary reaction zone feed branch line; 1-4 4.sup.th secondary reaction zone feed branch line; 2dense phase fluidized bed reactor; 2-1 1.sup.st secondary reaction zone; 2-2 2.sup.nd secondary reaction zone; 2-3 3.sup.rd secondary reaction zone; 2-4 4.sup.th secondary reaction zone; 3cyclone separator; 4product material line; 5stripper; 6water vapor line; 7lift pipe; 8lift gas line; 9feeding line for regenerator; 9-1 1.sup.st secondary regeneration zone feed branch line; 9-2 2.sup.nd secondary regeneration zone feed branch line; 9-3 3.sup.rd secondary regeneration zone feed branch line; 9-4 4.sup.th secondary regeneration zone feed branch line; 10dense phase fluidized bed regenerator; 10-1 1.sup.st secondary regeneration zone; 10-2 2.sup.nd secondary regeneration zone; 10-3 3.sup.rd secondary regeneration zone; 10-4 4.sup.th secondary regeneration zone; 11cyclone separator; 12exhaust gas line; 13stripper; 14water vapor line; 15lift pipe; 16lift gas line; 17material flow controller; 18material overflow port; 19partition plate; 20orifice; 21material downward flow pipe; 22bottom baffle; 23heat extraction member.

DETAILED DESCRIPTION OF THE INVENTION

[0035] In order to increase the selectivity for light olefins in the process of preparing light olefins from oxygen-containing compounds, this invention provides a reaction device for preparing light olefins from methanol and/or dimethyl ether, which mainly comprises a dense phase fluidized bed reactor (2), a cyclone separator (3), a stripper (5), a lift pipe (7), a dense phase fluidized bed regenerator (10), a cyclone separator (11), a stripper (13), and a lift pipe (15). A feeding line for reactor (1) is connected to the bottom of the dense phase fluidized bed reactor (2). A part of the stripper (5) is in the dense phase fluidized bed reactor (2), and the remaining part thereof is located below the dense phase fluidized bed reactor (2). The water vapor line (6) is connected to the bottom of the stripper (5). The bottom of the lift pipe (7) is connected to the bottom of the stripper (5). The lift gas line (8) is connected to the bottom of the lift pipe (7). The top of the lift pipe 7 is connected to the dense phase fluidized bed regenerator (10). The feeding line for regenerator (9) is connected to the bottom of the dense phase fluidized bed regenerator (10). A part of the stripper (13) is in the dense phase fluidized bed regenerator (10), and the remaining part thereof is located below the dense phase fluidized bed regenerator (10). The water vapor line (14) is connected to the bottom of the stripper (13). The bottom of the lift pipe (15) is connected to the bottom of the stripper (13). The lift gas line (16) is connected to the bottom of the lift pipe (15). The top of the lift pipe (15) is connected to the dense phase fluidized bed reactor (2). Preferably, the feeding line for reactor (1) comprises n reaction zone feed branch lines (1-1, . . . , 1-n), the dense phase fluidized bed reactor (2) is separated into n secondary reaction zones (2-1, . . . , 2-n) by a material flow controller (17), wherein n2 and preferably 8n3; n reaction zone feed branch lines are connected to n secondary reaction zones, respectively; and the 1.sup.st to the n.sup.th secondary reaction zones are sequentially connected, the top of the lift pipe (15) is connected to the 1.sup.st secondary reaction zone, the n.sup.th secondary reaction zone is connected to a material overflow port (18) on the upper part of the stripper (5), a cyclone separator (3) is provided on the upper part of the dense phase fluidized bed reactor (2), a top outlet of the cyclone separator (3) is connected to a product material line (4), and the bottom of the cyclone separator (3) is connected to the n.sup.th secondary reaction zone.

[0036] Preferably, the feeding line for regenerator (9) comprises m regeneration zone feed branch lines (9-1, . . . , 9-n), the dense phase fluidized bed regenerator (10) is separated into m secondary regeneration zones (10-1, . . . , 10-n) by the material flow controller (17), wherein m2 and preferably 8m3; m regeneration zone feed branch lines are connected to m secondary regeneration zones, respectively; and the 1.sup.st to the m.sup.th secondary regeneration zones are sequentially connected, the top of the lift pipe (7) is connected to the 1.sup.st secondary regeneration zone, the n.sup.th secondary regeneration zone is connected to a material overflow port (18) on the upper part of the stripper (13), a cyclone separator (11) is provided on the upper part of the dense phase fluidized bed regenerator (10), a top outlet of the cyclone separator (11) is connected to an exhaust gas line (12), and the bottom of the cyclone separator (11) is connected to the in secondary regeneration zone.

[0037] Preferably, the material flow controller (17) is composed of a partition plate (19), an orifice (20), a material downward flow pipe (21), a bottom baffle (22), and a heat extraction member (23). The orifice (20) is located below the partition plate (19) and is connected to the bottom of the material downward flow pipe (21), a porous plate or a nonporous plate may be used as the bottom baffle (22), which is located at the bottom of the material downward flow pipe (21) and the orifice (20), and the heat extraction member (23) is fixed on the partition plate (19).

[0038] In one preferred embodiment, the schematic flow chart of the process for preparing light olefins from methanol in this invention is as shown in FIG. 1. Raw materials, which are mainly methanol and/or dimethyl ether, are passed into the dense phase fluidized bed reactor (2) and are brought into contact with a catalyst to generate a gas phase product stream and a spent catalyst; the gas phase product stream and the entrained spent catalyst are passed into the cyclone separator (3), wherein the gas phase product stream is passed to a subsequent working section of separation via the outlet of the cyclone separator and the entrained spent catalyst is passed into the n.sup.th secondary reaction zone via the dipleg of the cyclone separator; the regenerated catalyst is passed into the dense phase fluidized bed reactor 2 via the stripper (13) and the lift pipe (15), and is sequentially passed through the 1.sup.st to the n.sup.th secondary reaction zones to form a spent catalyst after carbon deposition; and the spent catalyst is then passed into the dense phase fluidized bed regenerator (10) via the stripper (5) and the lift pipe (7), and is sequentially passed through the 1.sup.st to the m.sup.th secondary regeneration zones to form a regenerated catalyst after charking. The catalyst is preferably a catalyst comprising SAPO molecular sieve, and is further preferably a catalyst comprising SAPO-34 molecular sieve.

[0039] In a specific embodiment, the structural schematic diagram of the dense phase fluidized bed comprising 4 secondary reaction zones in this invention is as shown in FIG. 2, wherein the arrows in A-A sectional view show the flow directions of the catalyst between the secondary reaction zones. 3 material flow controllers (17) and a baffle are vertically provided to separate the dense phase fluidized bed reaction zone into 4 secondary reaction zones. The catalyst is sequentially passed through the 1.sup.st to the 4.sup.th secondary reaction zones and is then passed into the stripper.

[0040] In a specific embodiment, the structural schematic diagram of the dense phase fluidized bed comprising 4 secondary regeneration zones in this invention is as shown in FIG. 3, wherein the arrows in B-B sectional view show the flow directions of the catalyst between the secondary regeneration zones. 3 material flow controllers (17) and a baffle are vertically provided to separate the dense phase fluidized bed regeneration zone into 4 secondary regeneration zones. The catalyst is sequentially passed through the 1.sup.st to the 4.sup.th secondary regeneration zones and is then passed into the stripper.

[0041] Preferably, the structural schematic diagram of the strippers (5 and 13) in this invention is as shown in FIG. 4. The opening on the pipe wall on the upper part of the stripper (5) is used as the material overflow port (18) between the n.sup.th secondary reaction zone and the stripper (5). The opening on the pipe wall on the upper part of the stripper (13) is used as the material overflow port (18) between the m.sup.th secondary regeneration zone and the stripper (13).

[0042] Preferably, the structural schematic diagram of the material flow controller in this invention is as shown in FIG. 5. The material flow controller (17) is composed of a partition plate (19), an orifice (20), a material downward flow pipe (21), a bottom baffle (22), and a heat extraction member (23). The catalyst is passed into the material downward flow pipe from the top of the downward flow pipe, wherein the apparent gas linear velocity is less than or equal to the minimal fluidization speed, the catalyst in the material downward flow pipe is in a dense phase packing state, and a material flow driving force is formed to drive the catalyst to flow into a next secondary reaction zones (or regeneration zone) via the orifice. A coil structure may be used as the heat extraction member, which is fixed onto the partition plate.

[0043] Preferably, the apparent gas linear velocity in the dense phase fluidized bed reaction zone is 0.1-1.5 m/s; the apparent gas linear velocity in the dense phase fluidized bed regeneration zone is 0.1-1.5 m/s; the apparent gas linear velocity in the material flow controller is less than or equal to the minimal fluidization speed of the catalyst; the catalyst is preferably a catalyst comprising SAPO molecular sieve, and is further preferably a catalyst comprising SAPO-34 molecular sieve; a feed port is provided at the bottom of the reaction zone, and the feed comprises methanol and/or dimethyl ether, etc.; the stripping medium of the stripper (13) comprises water vapor; a regenerating medium inlet is provided at the bottom of the regeneration zone (10), and the regenerating medium comprises air, oxygen-depleted air, water vapor, etc.; the reaction zone (2) has a reaction temperature of 400-550 C. and a bed layer density of 200-1.200 kg/m.sup.3, and the average amount of carbon deposition of the catalyst sequentially increases from the 1.sup.st secondary reaction zone to the n.sup.th secondary reaction zone, wherein the average amount of carbon deposition of the 1.sup.st secondary reaction zone is 0.5-3 wt % and the average amount of carbon deposition of the n.sup.th secondary reaction zone is 7-10 wt %; and the regeneration zone (10) has a reaction temperature of 500-700 C. and a bed layer density of 200-1200 kg/m.sup.3, and the average amount of carbon deposition of the catalyst sequentially decreases from the 1.sup.st secondary regeneration zone to the m.sup.th secondary regeneration zone, wherein the average amount of carbon deposition of the 1.sup.st secondary regeneration zone is 3-10 wt % and the average amount of carbon deposition of the m.sup.th secondary regeneration zone is 0-3 wt %. The object of controlling the amount of carbon deposition on catalyst, improving the uniformity of carbon content, and increasing the selectivity of light olefins can be achieved by using the method of this invention, which has relatively high technical advantages and can be used in the industrial production of light olefins.

[0044] In order to heifer illustrate this invention and facilitate the understanding of the technical solution of this invention, typical and non-limiting Examples of this invention are as follows.

Example 1

[0045] 4 secondary reaction zones were provided in the dense phase fluidized bed reactor, and 4 secondary regeneration zones were provided in the dense phase fluidized bed regenerator. Raw materials, which were mainly methanol and/or dimethyl ether, were passed into the dense phase fluidized bed reactor and were brought into contact with a catalyst comprising SAPO-34 molecular sieve to generate a gas phase product stream and a spent catalyst. The gas phase material and the entrained spent catalyst were passed into the cyclone separator, wherein the gas phase product stream was passed to a subsequent working section of separation via the outlet of the cyclone separator and the entrained spent catalyst was passed into the 4.sup.th secondary reaction zone via the di Dog of the cyclone separator. The regenerated catalyst was passed into the dense phase fluidized bed reactor via the stripper and the lift pipe, and was sequentially passed through the 1.sup.st to the 4.sup.th secondary reaction zones to form a spent catalyst after carbon deposition. The spent catalyst was then passed into the dense phase fluidized bed regenerator via the stripper and the lift pipe, and was sequentially passed through the 1.sup.st to the 4.sup.th secondary regeneration zones to forma regenerated catalyst after charking. The reaction conditions of the dense phase fluidized bed reactor were as follows: the reaction temperature was 400 C., the gas phase linear velocity was 0.3 m/s, the bed layer density was 1000 kg/m.sup.3, the average amount of carbon deposition of the 1.sup.st secondary reaction zone was 2 wt %, the average amount of carbon deposition of the 2.sup.nd secondary reaction zone was 6 wt %, the average amount of carbon deposition of the 3.sup.rd secondary reaction zone was 8 wt %, and the average amount of carbon deposition of the 4.sup.th secondary reaction zone was 10 wt %. The reaction conditions of the dense phase fluidized bed regenerator were as follows: the reaction temperature was 500 C., the gas phase linear velocity was 0.3 m/s, the bed layer density was 1000 kg/m.sup.3, the average amount of carbon deposition of the 1.sup.st secondary regeneration zone was 7 wt %, the average amount of carbon deposition of the 2.sup.nd secondary regeneration zone was 4 wt %, the average amount of carbon deposition of the 3.sup.rd secondary regeneration zone was 2 wt %, and the average amount of carbon deposition of the 4.sup.th secondary regeneration zone was 1 wt %. The reaction product was analyzed by online gas chromatography, and the carbon based yield of light olefins was 91.1 wt %.

Example 2

[0046] 3 secondary reaction zones were provided in the dense phase fluidized bed reactor, and 2 secondary regeneration zones were provided in the dense phase fluidized bed regenerator. Raw materials, which were mainly methanol and/or dimethyl ether, were passed into the dense phase fluidized bed reactor and were brought into contact with a catalyst comprising SAPO-34 molecular sieve to generate a gas phase product stream and a spent catalyst. The gas phase material and the entrained spent catalyst were passed into the cyclone separator, wherein the gas phase product stream was passed to a subsequent working section of separation via the outlet of the cyclone separator and the entrained spent catalyst was passed into the 3.sup.rd secondary reaction zone via the dipleg of the cyclone separator. The regenerated catalyst was passed into the dense phase fluidized bed reactor via the stripper and the lift pipe, and was sequentially passed through the 1.sup.st to the 3.sup.rd secondary reaction zones to form a spent catalyst after carbon deposition. The spent catalyst was then passed into the dense phase fluidized bed regenerator via the stripper and the lift pipe, and was sequentially passed through the 1.sup.st to the 2.sup.nd secondary regeneration zones to form a regenerated catalyst after charking. The reaction conditions of the dense phase fluidized bed reactor were as follows: the reaction temperature was 450 C., the gas phase linear velocity was 0.5 m/s, the bed layer density was 900 kg/m.sup.3, the average amount of carbon deposition of the 1.sup.st secondary reaction zone was 3 wt %, the average amount of carbon deposition of the 2.sup.nd secondary reaction zone was 7 wt %, and the average amount of carbon deposition of the 3.sup.rd secondary reaction zone was 9 wt %. The reaction conditions of the dense phase fluidized bed regenerator were as follows: the reaction temperature was 600 C., the gas phase linear velocity was 0.7 m/s, the bed layer density was 700 kg/m.sup.3, the average amount of carbon deposition of the 1.sup.st secondary regeneration zone was 4 wt %, and the average amount of carbon deposition of the 2.sup.nd secondary regeneration zone was 2 wt %. The reaction product was analyzed by online gas chromatography, and the carbon based yield of light olefins was 90.5 wt %.

Example 3

[0047] 6 secondary reaction zones were provided in the dense phase fluidized bed reactor, and 5 secondary regeneration zones were provided in the dense phase fluidized bed regenerator. Raw materials, which were mainly methanol and/or dimethyl ether, were passed into the dense phase fluidized bed reactor and were brought into contact with a catalyst comprising SAPO-34 molecular sieve to generate a gas phase product stream and a spent catalyst. The gas phase material and the entrained spent catalyst were passed into the cyclone separator, wherein the gas phase product stream was passed to a subsequent working section of separation via the outlet of the cyclone separator and the entrained spent catalyst was passed into the 6.sup.th secondary reaction zone via the dipleg of the cyclone separator. The regenerated catalyst was passed into the dense phase fluidized bed reactor via the stripper and the lift pipe, and was sequentially passed through the 1.sup.st to the 6.sup.th secondary reaction zones to form a spent catalyst after carbon deposition. The spent catalyst was then passed into the dense phase fluidized bed regenerator via the stripper and the lift pipe, and was sequentially passed through the 1.sup.st to the 5.sup.th secondary regeneration zones to form a regenerated catalyst after charking. The reaction conditions of the dense phase fluidized bed reactor were as follows: the reaction temperature was 480 C., the gas phase linear velocity was 0.7 m/s, the bed layer density was 700 kg/m.sup.3, the average amount of carbon deposition of the 1.sup.st secondary reaction zone was 1 wt %, the average amount of carbon deposition of the 2.sup.nd secondary reaction zone was 3 wt %, the average amount of carbon deposition of the 3.sup.rd secondary reaction zone was 4 wt %, the average amount of carbon deposition of the 4.sup.th secondary reaction zone was 5 wt %, the average amount of carbon deposition of the 5.sup.th secondary reaction zone was 6 wt %, and the average amount of carbon deposition of the 6.sup.th secondary reaction zone was 7 wt %. The reaction conditions of the dense phase fluidized bed regenerator were as follows: the reaction temperature was 650 C., the gas phase linear velocity was 1.0 m/s, the bed layer density was 500 kg/m.sup.3, the average amount of carbon deposition of the 1.sup.st secondary regeneration zone was 5 wt %, the average amount of carbon deposition of the 2.sup.nd secondary regeneration zone was 3 wt %, the average amount of carbon deposition of the 3.sup.rd secondary regeneration zone was 2 wt %, the average amount of carbon deposition of the 4.sup.th secondary regeneration zone was 1 wt %, and the average amount of carbon deposition of the 5.sup.th secondary regeneration zone was 0.01 wt %. The reaction product was analyzed by online gas chromatography, and the carbon based yield of light olefins was 91.4 wt %.

[0048] This invention has been described in detail above, but this invention is not limited to specific embodiments described herein. It is to be understood by the person skilled in the art that other modifications and variations can be made without departing from the scope of the invention. The scope of the invention is defined by the appended claims.