Reactor for producing light olefins

Abstract

The present invention relates to the field of chemical technology, and discloses a reactor for preparing light olefins, comprising a cyclone body and a flow guide cylinder, wherein a cyclone chamber is provided in the cyclone body, a cyclone channel for a cyclone of raw gas to enter the cyclone chamber is provided on the circumferential wall of the cyclone body, and the cyclone chamber has a reaction area close to the circumferential wall of the cyclone chamber; the flow guide cylinder comprises an annular wall, which is arranged around the circumferential wall of the cyclone body, and an annular flow guide chamber is formed between the annular wall and the circumferential wall, and a raw gas inlet for the raw gas to enter the annular flow guide chamber is provided on the annular wall, wherein: a first end of the annular wall is provided with a product gas discharge port and a catalyst inlet respectively connected to the cyclone chamber, and a second end of the annular wall is provided with a catalyst outlet connected to the cyclone chamber. The reactor for preparing light olefins can enable the raw gas and the catalyst to react rapidly under cyclone operation, thereby reducing side reactions and improving the selectivity of the target product.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical industry, in particular to a reactor for preparing light olefins. Background Art

[0002] Light olefins such as ethylene and propylene are important basic chemical raw materials. With the development of my country's national economy, especially the modern chemical industry, demand for light olefins is increasing, and the imbalance between supply and demand is becoming increasingly prominent. The MTO process (methanol to ethylene and propylene) and the MTP process (methanol to propylene) are important chemical technologies. These technologies use methanol synthesized from coal or natural gas as a feedstock to produce light olefins, and are core technologies for developing non-petroleum resource-based production of products such as ethylene and propylene.

[0003] In the existing equipment for preparing low-carbon olefins, gas-solid circulating fluidized bed reactors are mainly used. In the process of preparing low-carbon systems, the raw gas carries the catalyst and flows against gravity, and a catalytic reaction occurs under the promotion of the catalyst. As a result, the gas-solid contact time of the entire process is relatively long, resulting in lower selectivity of the target product. Summary of the Invention

[0004] The purpose of the present invention is to provide a reactor for preparing light olefins, which can enable the raw gas and the catalyst to contact and separate quickly under cyclonic operation, thereby reducing side reactions in the preparation process and improving the selectivity of the target product.

[0005] In order to achieve the above object, the present invention provides a reactor for preparing light olefins, wherein the reactor comprises:

[0006] A cyclone body, wherein a cyclone chamber is provided in the cyclone body, a cyclone channel is provided on a circumferential wall of the cyclone body for allowing the cyclonic flow of the raw gas to enter the cyclone chamber, and the cyclone chamber has a reaction area close to the circumferential wall of the cyclone chamber; and

[0007] The flow guide cylinder comprises:

[0008] An annular wall is provided around the circumferential wall of the cyclone body, and an annular guide chamber is formed between the annular wall and the circumferential wall, and a raw gas inlet is provided on the annular wall for supplying raw gas into the annular guide chamber, wherein: a first end of the annular wall is provided with a product gas outlet and a catalyst inlet respectively connected to the cyclone chamber, and a second end of the annular wall is provided with a catalyst outlet connected to the cyclone chamber.

[0009] The above technical solution, by arranging a swirl channel on the swirl body, can enable the raw gas swirl to enter the swirl chamber. At the same time, combined with the action of gravitational acceleration of the catalyst particles, it can drive the catalyst to flow around in the annular reaction area close to the inner wall of the swirl chamber. As a result, the catalyst can be gathered on the inner wall surface of the swirl chamber. While the raw gas drives the catalyst swirl, it can quickly pass through the reaction area along the radial direction of the swirl chamber, realizing rapid contact and reaction between the raw gas and the catalyst, and timely discharge of the product gas, thereby reducing side reactions and improving the selectivity of the target product.

[0010] Preferably, the cyclone and the flow guide cylinder are both arranged sideways when the reactor for preparing light olefins is in a reaction state; and / or

[0011] A plurality of swirl channels are provided on the circumferential wall of the swirl body. On a projection plane perpendicular to the axial direction of the swirl chamber, the plurality of swirl channels are vortex-shaped.

[0012] Preferably, the flow guide cylinder includes a first closed surface provided at a first port of the annular wall, and the product gas outlet and the catalyst inlet are both provided at the first closed surface.

[0013] Preferably, the product gas outlet is arranged at the center of the cyclone chamber, and the catalyst inlet is arranged close to the reaction area.

[0014] Preferably, the reactor for preparing light olefins comprises a product gas outlet pipe provided at the product gas outlet, and the product gas outlet pipe extends into the cyclone chamber.

[0015] Preferably, the axial length of the product gas outlet pipe is less than half of the axial length of the cyclone chamber.

[0016] Preferably, the reactor for preparing light olefins includes a catalyst inlet pipe, which includes a first pipe section arranged at the catalyst inlet, the first pipe section being arranged obliquely to the axis of the flow guide cylinder, and the catalyst inlet pipe also includes a second pipe section connected to the first pipe section and extending radially along the flow guide cylinder.

[0017] Preferably, the angle formed by the axis of the first pipe section and the first closed surface is greater than 0° and less than 90°.

[0018] Preferably, the reactor for preparing light olefins includes a catalyst outlet pipe, which includes an inclined pipe section arranged at the catalyst outlet and an outlet pipe section connected to the inclined pipe section, wherein: the inclined pipe section is arranged inclined to the axis of the flow guide cylinder, and the outlet pipe section extends radially along the flow guide cylinder.

[0019] Preferably, the flow guide cylinder includes a tapered portion provided at the second port of the annular wall, the tapered portion is tapered in the direction from the catalyst inlet to the catalyst outlet, and the catalyst outlet is provided at the end surface of the tapered portion.

[0020] Preferably, the catalyst outlet is arranged to be offset from the center of the end surface of the tapered portion.

[0021] Preferably, the reactor for preparing light olefins comprises a baffle disposed in the conical portion, wherein the baffle extends from the circumferential wall of the conical portion toward the center of the conical portion.

[0022] Preferably, the reactor for preparing light olefins comprises a plurality of the baffles, and the plurality of the baffles are distributed at intervals along the circumference of the tapered portion.

[0023] Preferably, the axial length of the tapered portion is less than or equal to the axial length of the cyclone chamber.

[0024] Preferably, the reactor for preparing light olefins comprises a heat transfer mechanism disposed in the cyclone chamber, and the heat transfer mechanism is configured to cool the product gas obtained by the reaction.

[0025] Preferably, the cyclone chamber has a separation area close to the center of the cyclone chamber, and the heat transfer mechanism is arranged in the separation area.

[0026] Preferably, the heat transfer mechanism comprises a heat transfer pipe provided at the periphery of the product gas outlet, wherein the heat transfer pipe allows a cooling medium for cooling the product gas to pass through, and the heat transfer pipe extends along the axial direction of the cyclone chamber.

[0027] Preferably, the heat transfer mechanism includes a plurality of heat transfer tubes, and the plurality of heat transfer tubes are arranged around the product gas outlet.

[0028] Preferably, the heat transfer tube extends beyond the first end of the annular wall.

[0029] Preferably, the reactor for preparing light olefins comprises a guide plate arranged on the periphery of the heat transfer tube away from the center of the cyclone chamber, and the guide plate is configured to guide the product gas obtained by the reaction to flow toward the product gas outlet.

[0030] Preferably, the guide plate is provided on the corresponding heat transfer tube, and the guide plate is inclined relative to a section passing through a connection point between the guide plate and the corresponding heat transfer tube and an outer wall surface of the heat transfer tube.

[0031] Preferably, the reactor for preparing light olefins comprises a plurality of guide plates arranged on the periphery of the heat transfer tube, and the plurality of guide plates are in a vortex shape. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a reactor for preparing light olefins according to a preferred embodiment of the present invention;

[0033] Figure 2 It is along Figure 1 Schematic diagram of the cross-section structure taken along line AA;

[0034] Figure 3 yes Figure 1 Another preferred cross-sectional structural schematic diagram of a reactor for preparing light olefins is shown;

[0035] Figure 4 yes Figure 3 The cross-sectional structure diagram of the heat transfer tube in the reactor for preparing light olefins is shown, wherein a guide plate is provided.

[0036] Description of Reference Numerals

[0037] 10-reactor for preparing light olefins; 11-cyclone body; 110-cyclone chamber; 112-cyclone channel; 12-flow guide cylinder; 12a-annular wall; 120-annular flow guide chamber; 122-feed gas inlet; 14a-product gas outlet pipe; 14b-catalyst inlet pipe; 140b-first pipe section; 142b-second pipe section; 14c-catalyst outlet pipe; 140c-inclined pipe section; 142c-export pipe section; 14d-feed gas inlet pipe; 16-tapered portion; 160-baffle; 18-heat transfer mechanism; 180-heat transfer pipe; 182-flow guide plate. DETAILED DESCRIPTION

[0038] In the present invention, unless otherwise specified, directional words such as "up, down, left, right" generally refer to the directions shown in the drawings and actual applications, and "inside and outside" refer to the inside and outside of the outline of the component.

[0039] It should be noted that the raw gas can be reacted under the catalytic promotion of a catalyst such as SAPO-34 molecular sieve to produce olefins with 2-3 carbon atoms such as ethylene and propylene. The raw gas can be selected from alcohols such as methanol.

[0040] The present invention provides a reactor for preparing light olefins, Figure 1 and Figure 2As shown in, the reactor 10 for preparing light olefins includes a cyclone 11, a cyclone chamber 110 is provided in the cyclone 11, and a cyclone channel 112 for the raw gas cyclone to enter the cyclone chamber 110 is provided on the circumferential wall of the cyclone 11, and the cyclone chamber 110 has a reaction area close to the circumferential wall of the cyclone chamber 110. It should be noted that the raw gas entering through the cyclone channel 112 flows in the reaction area after entering the cyclone chamber 110. In this way, the raw gas can also drive the catalyst entering the cyclone chamber 110, and can combine the gravitational acceleration of the catalyst itself to make a circumferential flow movement along the reaction area close to the inner wall of the cyclone chamber 110, and react in the reaction area to obtain light olefins, wherein the reaction area is annular; the reactor 10 for preparing light olefins also includes a flow guide cylinder 12, the flow guide cylinder 12 includes an annular wall 12a, and the annular wall 12a is arranged around the circumferential wall of the cyclone 11, and An annular guide chamber 120 is formed between the annular wall 12a and the circumferential wall. A raw gas inlet 122 is provided on the annular wall 12a for the raw gas to enter the annular guide chamber 120, wherein: the first end of the annular wall 12a is provided with a product gas outlet and a catalyst inlet which are respectively connected to the cyclone chamber 110, and the second end of the annular wall 12a is provided with a catalyst outlet which is connected to the cyclone chamber 110. The raw gas enters the annular guide chamber 120 from the raw gas inlet 122, and flows in an annular direction in the annular guide chamber 120. During the flow, the raw gas enters the cyclone chamber 110 from the cyclone channel 112. Afterwards, the raw gas drives the catalyst entering from the catalyst inlet to flow around in the reaction area, and reacts in the reaction area to obtain product gas, i.e., low-carbon olefins. Finally, the product gas can flow toward the center of the cyclone chamber 110 and be discharged from the product gas outlet, while the reacted catalyst is discharged from the catalyst outlet. By providing a swirl channel 112 on the swirl body 11, the raw gas swirl can enter the swirl chamber 110 and drive the catalyst to flow around the annular reaction area near the inner wall of the swirl chamber 110. This allows the reaction to occur quickly and the product gas obtained by the reaction to be discharged in a timely manner. In this way, side reactions are greatly reduced and the selectivity of the target product is improved. It should also be noted that the swirl chamber 110 may also have a separation area near the center of the swirl chamber 110. The product gas obtained by the reaction can flow toward the separation area and ultimately be discharged from the product gas outlet, wherein the separation area can be distributed around the center of the swirl chamber 110 and the separation area can be annular.

[0041] It should be noted that the gas velocity of the raw gas entering the cyclone channel 112 can be controlled to be 10 m / s-30 m / s, so that the raw gas cyclone can be ensured to flow around in the reaction area after entering the cyclone chamber 110; before the raw gas is introduced into the reactor 10 for preparing light olefins, the raw gas can be preheated, for example, the raw gas can be preheated to 100°C-200°C; the average carbon deposition of the catalyst can be 0.5wt%-6wt%, and more preferably, the average carbon deposition of the catalyst can be 4wt%-5wt%; the contact time between the raw gas and the catalyst can be controlled to be 0.1s-2s, and preferably, the contact time can be controlled to be 0.2s-0.5s; the reaction temperature of the reaction area in the cyclone chamber 110 can be controlled to be 350°C-510°C, the reaction pressure in the reaction area can be controlled to be 0.01MPa-1MPa, and the temperature of the separation area can be controlled to be 150°C-350°C.

[0042] The cyclone 11 and the flow guide cylinder 12 are both arranged sideways when the reactor 10 for preparing light olefins is in a reaction state. Figure 1 As shown in the orientation, the cyclone body 11 and the flow guide cylinder 12 are both arranged sideways. In this way, the cyclone chamber 110 is also in a sideways state.

[0043] Combine Figure 2 and Figure 3 As shown in , a plurality of swirl channels 112 may be provided on the circumferential wall of the swirl body 11. In a projection plane perpendicular to the axial direction of the swirl chamber 110, the plurality of swirl channels 112 may be vortex-shaped. The number of swirl channels 112 may be 4-10, preferably 6-8. The swirl channels 112 may be substantially inclined.

[0044] In order to further ensure the swirl effect and ensure that the raw gas passes through the reaction area quickly, the angle α between the axis of the swirl channel 112 and the corresponding tangent of the outer wall of the swirl chamber 110 can be less than 90°. Preferably, the angle α can be 20°-55°.

[0045] A first closed surface can be provided at the first port of annular wall 12a, and both the product gas outlet and the catalyst inlet can be located on this first closed surface. To ensure smooth discharge of product gas, the product gas outlet can be located at the center of cyclone chamber 110. Furthermore, the catalyst inlet can be positioned near the reaction zone, allowing the catalyst to be discharged directly into the reaction zone, thereby increasing the reaction rate and further reducing the occurrence of side reactions.

[0046] Combine Figure 1 and Figure 2As shown in FIG, a product gas outlet pipe 14a can be provided at the product gas outlet. The product gas outlet pipe 14a can extend axially along the cyclone chamber 110 and extend into the cyclone chamber 110. In this way, the product gas outlet pipe 14a can conveniently guide the product gas out of the guide cylinder 12. The axial length of the product gas outlet pipe 14a can be less than half the axial length of the cyclone chamber 110.

[0047] Combine Figure 2 and Figure 3 As shown in , a raw gas introduction pipe 14d can be set at the raw gas inlet 122 to facilitate the introduction of the raw gas into the annular guide chamber 120.

[0048] In addition, a catalyst introduction pipe 14b may be provided, such as Figure 1 As shown in , the catalyst introduction pipe 14b may include a first pipe section 140b provided at the catalyst inlet, the first pipe section 140b may be provided obliquely to the axis of the flow guide cylinder 12, and the catalyst introduction pipe 14b may further include a second pipe section 142b connected to the first pipe section 140b and extending radially along the flow guide cylinder 12, wherein the first pipe section 140b may be provided below the second pipe section 142b, so that the catalyst may enter the cyclone chamber 110 by gravity and stably enter the cyclone chamber 110 under the action of the first pipe section 140b. The angle β formed by the axis of the first pipe section 140b and the first closed surface may be greater than 0° and less than 90°, and further preferably, the angle β may be 20°-30°.

[0049] In order to facilitate the smooth discharge of the catalyst, a tapered portion 16 can be provided at the second port of the annular wall 12a. The tapered portion 16 is tapered in the direction from the catalyst inlet to the catalyst outlet. The catalyst outlet can be provided at the end face of the tapered portion 16. It is understood that the end face is away from the second port of the annular wall 12a. The catalyst outlet can be provided to deviate from the center of the end face of the tapered portion 16. Figure 1 From the perspective shown, the catalyst outlet can be positioned below the center of the end surface of the tapered portion 16. This prevents the product gas from being discharged from the catalyst outlet along with the catalyst, further reducing the probability of the product gas being discharged from the catalyst outlet. The axial length of the tapered portion 16 can be less than or equal to the axial length of the cyclone chamber 110. Preferably, the axial length of the tapered portion 16 can be 1 / 3 to 2 / 3 of the axial length of the cyclone chamber 110.

[0050] In addition, a catalyst outlet pipe 14c may be provided, such as Figure 1As shown in , the catalyst outlet pipe 14c may include an inclined pipe section 140c disposed at the catalyst outlet and an outlet pipe section 142c connected to the inclined pipe section 140c, wherein: the inclined pipe section 140c may be disposed obliquely with respect to the axis of the flow guide cylinder 12, and the outlet pipe section 142c may extend radially along the flow guide cylinder 12, so that the reacted catalyst swirls out of the catalyst outlet and is discharged from the catalyst outlet pipe 14c. The outlet pipe section 142c may be disposed below the inclined pipe section 140c, and the catalyst may be discharged out of the catalyst outlet pipe 14c by gravity. The angle formed between the axis of the inclined pipe section 140c and the end surface of the tapered portion 16 is 15°-45°.

[0051] like Figure 3 As shown in FIG, a baffle 160 may be provided within the conical portion 16. The baffle 160 may extend from the circumferential wall of the conical portion 16 toward the center of the conical portion 16. The provision of the baffle 160 may change the flow state of the catalyst, thereby intercepting the catalyst flow and enabling rapid discharge of the catalyst. It will be appreciated that the baffle 160 extends generally in the radial direction of the cyclone chamber 110.

[0052] In order to further enable the catalyst to be discharged quickly, a plurality of baffles 160 may be provided. The plurality of baffles 160 may be distributed at intervals along the circumference of the tapered portion 16 .

[0053] A heat transfer mechanism 18 may be provided in the cyclone chamber 110. The heat transfer mechanism 18 may be configured to cool the product gas obtained by the reaction. By rapidly cooling the product gas, a temperature gradient is formed after the gas phase passes through the catalyst aggregation layer, thereby further suppressing the occurrence of side reactions.

[0054] It is understood that the cyclone chamber 110 may have a separation area near the center of the cyclone chamber 110, and the heat transfer mechanism 18 may be disposed in the separation area, so that the product gas can be better cooled. In addition, the heat transfer mechanism 18 can also turbulently control the reaction process.

[0055] The heat transfer mechanism 18 may include a heat transfer pipe 180 disposed around the periphery of the product gas outlet. A cooling medium for cooling the product gas can pass through the heat transfer pipe 180, and the heat transfer pipe 180 may extend axially along the swirl chamber 110. The heat transfer pipe 180 may be U-shaped. Furthermore, the heat transfer pipe 180 may extend beyond the first end of the annular wall 12a. The length of the heat transfer pipe 180 extending beyond the first end may be less than the sum of the axial lengths of the swirl chamber 110 and the axial length of the tapered portion 16, and may be greater than the length of the product gas outlet pipe 14a extending into the swirl chamber 110.

[0056] In order to further improve the cooling effect, a plurality of heat transfer pipes 180 may be provided. The plurality of heat transfer pipes 180 may be provided around the product gas outlet and may be evenly distributed along the circumference of the product gas outlet.

[0057] Combine Figure 3 and Figure 4 As shown in the figure, a guide plate 182 can be set on the periphery of the heat transfer pipe 180 away from the center of the cyclone chamber 110. The guide plate 182 can be set to guide the product gas obtained by the reaction to flow toward the product gas outlet. The guide plate 182 can play a role in drainage, shortening the movement trajectory of the product gas, allowing the product gas to be quickly discharged from the product gas outlet, and greatly reducing the residence time of the gas phase in the reactor 10 for preparing light olefins.

[0058] The guide plate 182 can be installed on the corresponding heat transfer tube 180. It is understood that the guide plate 182 can be connected to the corresponding heat transfer tube 180 and can be inclined relative to a cross-section passing through the connection point between the guide plate 182 and the corresponding heat transfer tube 180 and the outer wall of the heat transfer tube 180. The angle φ formed between the guide plate 182 and the corresponding cross-section can be less than or equal to 30° and greater than or equal to 90°. Multiple guide plates 182 can be installed around the periphery of the heat transfer tube 180, and these multiple guide plates 182 can be arranged in a vortex shape to further enhance the drainage effect and ensure that the product gas is quickly discharged from the product gas outlet.

[0059] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, the technical solution of the present invention may be subjected to a variety of simple modifications, including combining the various specific technical features in any suitable manner. To avoid unnecessary repetition, the present invention will not further describe various possible combinations. However, these simple modifications and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A reactor for preparing light olefins, characterized in that: The reactor (10) for preparing light olefins comprises: A cyclone body (11), wherein a cyclone chamber (110) is provided in the cyclone body (11), a cyclone channel (112) for allowing a cyclone of raw gas to enter the cyclone chamber (110) is provided on a circumferential wall of the cyclone body (11), and the cyclone chamber (110) has a reaction area close to the circumferential wall of the cyclone chamber (110); A flow guide cylinder (12), wherein the flow guide cylinder (12) comprises: an annular wall (12a), the annular wall (12a) being arranged around the circumferential wall of the cyclone (11), and an annular guide chamber (120) being formed between the annular wall (12a) and the circumferential wall, the annular wall (12a) being provided with a raw gas inlet (122) for supplying raw gas to the annular guide chamber (120), wherein: a first end of the annular wall (12a) is provided with a product gas outlet and a catalyst inlet respectively connected to the cyclone chamber (110), and a second end of the annular wall (12a) is provided with a catalyst outlet connected to the cyclone chamber (110); and, A heat transfer mechanism (18), the heat transfer mechanism (18) is arranged in the cyclone chamber (110), the heat transfer mechanism (18) is arranged to cool the product gas obtained by the reaction, the cyclone chamber (110) has a separation area close to the center of the cyclone chamber (110), the heat transfer mechanism (18) is arranged in the separation area, the heat transfer mechanism (18) includes a heat transfer pipe (180) arranged on the periphery of the product gas outlet, the heat transfer pipe (180) allows a cooling medium for cooling the product gas to pass through, and the heat transfer pipe (180) is arranged along the axis of the cyclone chamber (110). The heat transfer tube (180) extends in a direction opposite to the first end of the annular wall (12a). A peripheral guide plate (182) is provided on the heat transfer tube (180) at a point away from the center of the cyclone chamber (110). The guide plate (182) is configured to guide the product gas obtained by the reaction to flow toward the product gas outlet. The guide plate (182) is provided on the corresponding heat transfer tube (180), and the guide plate (182) is inclined relative to a section of a connecting point between the guide plate (182) and the corresponding heat transfer tube (180) and an outer wall surface of the heat transfer tube (180).

2. The reactor for preparing light olefins according to claim 1, characterized in that: The cyclone (11) and the flow guide cylinder (12) are both arranged sideways when the reactor (10) for preparing light olefins is in a reaction state.

3. The reactor for preparing light olefins according to claim 1, characterized in that: A plurality of swirl channels (112) are provided on the circumferential wall of the swirl body (11), and on a projection plane perpendicular to the axial direction of the swirl chamber (110), the plurality of swirl channels (112) are vortex-shaped.

4. The reactor for preparing light olefins according to claim 1, characterized in that: The flow guide cylinder (12) comprises a first closed surface provided at a first port of the annular wall (12a), and the product gas outlet and the catalyst inlet are both provided at the first closed surface.

5. The reactor for preparing light olefins according to claim 4, characterized in that: The product gas outlet is arranged at the center of the cyclone chamber (110), and the catalyst inlet is arranged close to the reaction area.

6. The reactor for preparing light olefins according to claim 4, characterized in that: The reactor (10) for preparing light olefins comprises a product gas outlet pipe (14a) arranged at the product gas outlet, and the product gas outlet pipe (14a) extends into the cyclone chamber (110).

7. The reactor for preparing light olefins according to claim 6, characterized in that: The axial length of the product gas outlet pipe (14a) is less than half the axial length of the cyclone chamber (110).

8. The reactor for preparing light olefins according to claim 4, characterized in that: The reactor (10) for preparing light olefins includes a catalyst inlet pipe (14b), the catalyst inlet pipe (14b) includes a first pipe section (140b) arranged at the catalyst inlet, the first pipe section (140b) is arranged obliquely to the axis of the flow guide cylinder (12), and the catalyst inlet pipe (14b) also includes a second pipe section (142b) connected to the first pipe section (140b) and extending along the radial direction of the flow guide cylinder (12).

9. The reactor for preparing light olefins according to claim 8, characterized in that: The angle formed by the axis of the first pipe section (140b) and the first closed surface is greater than 0° and less than 90°.

10. The reactor for preparing light olefins according to claim 1, characterized in that: The reactor (10) for preparing light olefins includes a catalyst outlet pipe (14c), and the catalyst outlet pipe (14c) includes an inclined pipe section (140c) arranged at the catalyst outlet and an outlet pipe section (142c) connected to the inclined pipe section (140c), wherein: the inclined pipe section (140c) is arranged to be inclined with respect to the axis of the flow guide cylinder (12), and the outlet pipe section (142c) extends along the radial direction of the flow guide cylinder (12).

11. The reactor for preparing light olefins according to claim 1, characterized in that: The flow guide cylinder (12) comprises a tapered portion (16) arranged at a second port of the annular wall (12a), the tapered portion (16) being tapered in a direction from the catalyst inlet to the catalyst outlet, and the catalyst outlet being arranged at an end surface of the tapered portion (16).

12. The reactor for preparing light olefins according to claim 11, characterized in that: The catalyst outlet is arranged to be offset from the center of the end surface of the tapered portion (16).

13. The reactor for preparing light olefins according to claim 11, characterized in that: The reactor (10) for preparing light olefins comprises a baffle (160) arranged in the conical portion (16), wherein the baffle (160) extends from the circumferential wall of the conical portion (16) toward the center of the conical portion (16).

14. The reactor for preparing light olefins according to claim 13, characterized in that: The reactor (10) for preparing light olefins comprises a plurality of baffles (160), and the plurality of baffles (160) are distributed at intervals along the circumference of the tapered portion (16).

15. The reactor for preparing light olefins according to claim 11, characterized in that: The axial length of the tapered portion (16) is less than or equal to the axial length of the cyclone chamber (110).

16. The reactor for preparing light olefins according to claim 1, characterized in that: The heat transfer mechanism (18) comprises a plurality of heat transfer pipes (180), and the plurality of heat transfer pipes (180) are arranged around the product gas outlet.

17. The reactor for preparing light olefins according to claim 16, characterized in that: The reactor (10) for preparing light olefins comprises a plurality of guide plates (182) arranged on the periphery of the heat transfer pipe (180), and the plurality of guide plates (182) are vortex-shaped.

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